anno_start	anno_end	anno_text	entity_type	sentence	section
27	42	peptide hormone	protein_type	Mechanistic insight into a peptide hormone signaling complex mediating floral organ abscission	TITLE
0	6	Plants	taxonomy_domain	Plants constantly renew during their life cycle and thus require to shed senescent and damaged organs.	ABSTRACT
39	74	leucine-rich repeat receptor kinase	protein_type	Floral abscission is controlled by the leucine-rich repeat receptor kinase (LRR-RK) HAESA and the peptide hormone IDA.	ABSTRACT
76	82	LRR-RK	protein_type	Floral abscission is controlled by the leucine-rich repeat receptor kinase (LRR-RK) HAESA and the peptide hormone IDA.	ABSTRACT
84	89	HAESA	protein	Floral abscission is controlled by the leucine-rich repeat receptor kinase (LRR-RK) HAESA and the peptide hormone IDA.	ABSTRACT
98	113	peptide hormone	protein_type	Floral abscission is controlled by the leucine-rich repeat receptor kinase (LRR-RK) HAESA and the peptide hormone IDA.	ABSTRACT
114	117	IDA	protein	Floral abscission is controlled by the leucine-rich repeat receptor kinase (LRR-RK) HAESA and the peptide hormone IDA.	ABSTRACT
32	35	IDA	protein	It is unknown how expression of IDA in the abscission zone leads to HAESA activation.	ABSTRACT
68	73	HAESA	protein	It is unknown how expression of IDA in the abscission zone leads to HAESA activation.	ABSTRACT
18	21	IDA	protein	Here we show that IDA is sensed directly by the HAESA ectodomain.	ABSTRACT
48	53	HAESA	protein	Here we show that IDA is sensed directly by the HAESA ectodomain.	ABSTRACT
54	64	ectodomain	structure_element	Here we show that IDA is sensed directly by the HAESA ectodomain.	ABSTRACT
0	18	Crystal structures	evidence	Crystal structures of HAESA in complex with IDA reveal a hormone binding pocket that accommodates an active dodecamer peptide.	ABSTRACT
22	27	HAESA	protein	Crystal structures of HAESA in complex with IDA reveal a hormone binding pocket that accommodates an active dodecamer peptide.	ABSTRACT
28	43	in complex with	protein_state	Crystal structures of HAESA in complex with IDA reveal a hormone binding pocket that accommodates an active dodecamer peptide.	ABSTRACT
44	47	IDA	protein	Crystal structures of HAESA in complex with IDA reveal a hormone binding pocket that accommodates an active dodecamer peptide.	ABSTRACT
57	79	hormone binding pocket	site	Crystal structures of HAESA in complex with IDA reveal a hormone binding pocket that accommodates an active dodecamer peptide.	ABSTRACT
101	107	active	protein_state	Crystal structures of HAESA in complex with IDA reveal a hormone binding pocket that accommodates an active dodecamer peptide.	ABSTRACT
108	117	dodecamer	structure_element	Crystal structures of HAESA in complex with IDA reveal a hormone binding pocket that accommodates an active dodecamer peptide.	ABSTRACT
118	125	peptide	chemical	Crystal structures of HAESA in complex with IDA reveal a hormone binding pocket that accommodates an active dodecamer peptide.	ABSTRACT
10	24	hydroxyproline	residue_name	A central hydroxyproline residue anchors IDA to the receptor.	ABSTRACT
41	44	IDA	protein	A central hydroxyproline residue anchors IDA to the receptor.	ABSTRACT
4	9	HAESA	protein	The HAESA co-receptor SERK1, a positive regulator of the floral abscission pathway, allows for high-affinity sensing of the peptide hormone by binding to an Arg-His-Asn motif in IDA.	ABSTRACT
10	21	co-receptor	protein_type	The HAESA co-receptor SERK1, a positive regulator of the floral abscission pathway, allows for high-affinity sensing of the peptide hormone by binding to an Arg-His-Asn motif in IDA.	ABSTRACT
22	27	SERK1	protein	The HAESA co-receptor SERK1, a positive regulator of the floral abscission pathway, allows for high-affinity sensing of the peptide hormone by binding to an Arg-His-Asn motif in IDA.	ABSTRACT
124	139	peptide hormone	protein_type	The HAESA co-receptor SERK1, a positive regulator of the floral abscission pathway, allows for high-affinity sensing of the peptide hormone by binding to an Arg-His-Asn motif in IDA.	ABSTRACT
157	174	Arg-His-Asn motif	structure_element	The HAESA co-receptor SERK1, a positive regulator of the floral abscission pathway, allows for high-affinity sensing of the peptide hormone by binding to an Arg-His-Asn motif in IDA.	ABSTRACT
178	181	IDA	protein	The HAESA co-receptor SERK1, a positive regulator of the floral abscission pathway, allows for high-affinity sensing of the peptide hormone by binding to an Arg-His-Asn motif in IDA.	ABSTRACT
25	34	conserved	protein_state	This sequence pattern is conserved among diverse plant peptides, suggesting that plant peptide hormone receptors may share a common ligand binding mode and activation mechanism.	ABSTRACT
49	54	plant	taxonomy_domain	This sequence pattern is conserved among diverse plant peptides, suggesting that plant peptide hormone receptors may share a common ligand binding mode and activation mechanism.	ABSTRACT
55	63	peptides	chemical	This sequence pattern is conserved among diverse plant peptides, suggesting that plant peptide hormone receptors may share a common ligand binding mode and activation mechanism.	ABSTRACT
81	86	plant	taxonomy_domain	This sequence pattern is conserved among diverse plant peptides, suggesting that plant peptide hormone receptors may share a common ligand binding mode and activation mechanism.	ABSTRACT
87	112	peptide hormone receptors	protein_type	This sequence pattern is conserved among diverse plant peptides, suggesting that plant peptide hormone receptors may share a common ligand binding mode and activation mechanism.	ABSTRACT
0	6	Plants	taxonomy_domain	Plants can shed their leaves, flowers or other organs when they no longer need them. But how does a leaf or a flower know when to let go? A receptor protein called HAESA is found on the surface of the cells that surround a future break point on the plant. When its time to shed an organ, a hormone called IDA instructs HAESA to trigger the shedding process.	ABSTRACT
140	156	receptor protein	protein_type	Plants can shed their leaves, flowers or other organs when they no longer need them. But how does a leaf or a flower know when to let go? A receptor protein called HAESA is found on the surface of the cells that surround a future break point on the plant. When its time to shed an organ, a hormone called IDA instructs HAESA to trigger the shedding process.	ABSTRACT
164	169	HAESA	protein	Plants can shed their leaves, flowers or other organs when they no longer need them. But how does a leaf or a flower know when to let go? A receptor protein called HAESA is found on the surface of the cells that surround a future break point on the plant. When its time to shed an organ, a hormone called IDA instructs HAESA to trigger the shedding process.	ABSTRACT
290	297	hormone	chemical	Plants can shed their leaves, flowers or other organs when they no longer need them. But how does a leaf or a flower know when to let go? A receptor protein called HAESA is found on the surface of the cells that surround a future break point on the plant. When its time to shed an organ, a hormone called IDA instructs HAESA to trigger the shedding process.	ABSTRACT
305	308	IDA	protein	Plants can shed their leaves, flowers or other organs when they no longer need them. But how does a leaf or a flower know when to let go? A receptor protein called HAESA is found on the surface of the cells that surround a future break point on the plant. When its time to shed an organ, a hormone called IDA instructs HAESA to trigger the shedding process.	ABSTRACT
319	324	HAESA	protein	Plants can shed their leaves, flowers or other organs when they no longer need them. But how does a leaf or a flower know when to let go? A receptor protein called HAESA is found on the surface of the cells that surround a future break point on the plant. When its time to shed an organ, a hormone called IDA instructs HAESA to trigger the shedding process.	ABSTRACT
38	41	IDA	protein	However, the molecular details of how IDA triggers organ shedding are not clear.	ABSTRACT
75	80	plant	taxonomy_domain	The shedding of floral organs (or leaves) can be easily studied in a model plant called Arabidopsis.	ABSTRACT
88	99	Arabidopsis	taxonomy_domain	The shedding of floral organs (or leaves) can be easily studied in a model plant called Arabidopsis.	ABSTRACT
21	41	protein biochemistry	experimental_method	Santiago et al. used protein biochemistry, structural biology and genetics to uncover how the IDA hormone activates HAESA.	ABSTRACT
43	61	structural biology	experimental_method	Santiago et al. used protein biochemistry, structural biology and genetics to uncover how the IDA hormone activates HAESA.	ABSTRACT
66	74	genetics	experimental_method	Santiago et al. used protein biochemistry, structural biology and genetics to uncover how the IDA hormone activates HAESA.	ABSTRACT
94	97	IDA	protein	Santiago et al. used protein biochemistry, structural biology and genetics to uncover how the IDA hormone activates HAESA.	ABSTRACT
98	105	hormone	chemical	Santiago et al. used protein biochemistry, structural biology and genetics to uncover how the IDA hormone activates HAESA.	ABSTRACT
116	121	HAESA	protein	Santiago et al. used protein biochemistry, structural biology and genetics to uncover how the IDA hormone activates HAESA.	ABSTRACT
26	29	IDA	protein	The experiments show that IDA binds directly to a canyon shaped pocket in HAESA that extends out from the surface of the cell.	ABSTRACT
30	47	binds directly to	protein_state	The experiments show that IDA binds directly to a canyon shaped pocket in HAESA that extends out from the surface of the cell.	ABSTRACT
50	63	canyon shaped	protein_state	The experiments show that IDA binds directly to a canyon shaped pocket in HAESA that extends out from the surface of the cell.	ABSTRACT
64	70	pocket	site	The experiments show that IDA binds directly to a canyon shaped pocket in HAESA that extends out from the surface of the cell.	ABSTRACT
74	79	HAESA	protein	The experiments show that IDA binds directly to a canyon shaped pocket in HAESA that extends out from the surface of the cell.	ABSTRACT
0	3	IDA	protein	IDA binding to HAESA allows another receptor protein called SERK1 to bind to HAESA, which results in the release of signals inside the cell that trigger the shedding of organs.	ABSTRACT
15	20	HAESA	protein	IDA binding to HAESA allows another receptor protein called SERK1 to bind to HAESA, which results in the release of signals inside the cell that trigger the shedding of organs.	ABSTRACT
36	52	receptor protein	protein_type	IDA binding to HAESA allows another receptor protein called SERK1 to bind to HAESA, which results in the release of signals inside the cell that trigger the shedding of organs.	ABSTRACT
60	65	SERK1	protein	IDA binding to HAESA allows another receptor protein called SERK1 to bind to HAESA, which results in the release of signals inside the cell that trigger the shedding of organs.	ABSTRACT
66	76	to bind to	protein_state	IDA binding to HAESA allows another receptor protein called SERK1 to bind to HAESA, which results in the release of signals inside the cell that trigger the shedding of organs.	ABSTRACT
77	82	HAESA	protein	IDA binding to HAESA allows another receptor protein called SERK1 to bind to HAESA, which results in the release of signals inside the cell that trigger the shedding of organs.	ABSTRACT
90	93	IDA	protein	The next step following on from this work is to understand what signals are produced when IDA activates HAESA.	ABSTRACT
104	109	HAESA	protein	The next step following on from this work is to understand what signals are produced when IDA activates HAESA.	ABSTRACT
44	47	IDA	protein	Another challenge will be to find out where IDA is produced in the plant and what causes it to accumulate in specific places in preparation for organ shedding.	ABSTRACT
67	72	plant	taxonomy_domain	Another challenge will be to find out where IDA is produced in the plant and what causes it to accumulate in specific places in preparation for organ shedding.	ABSTRACT
4	9	HAESA	protein	The HAESA ectodomain folds into a superhelical assembly of 21 leucine-rich repeats.	FIG
10	20	ectodomain	structure_element	The HAESA ectodomain folds into a superhelical assembly of 21 leucine-rich repeats.	FIG
34	55	superhelical assembly	structure_element	The HAESA ectodomain folds into a superhelical assembly of 21 leucine-rich repeats.	FIG
62	82	leucine-rich repeats	structure_element	The HAESA ectodomain folds into a superhelical assembly of 21 leucine-rich repeats.	FIG
4	12	SDS PAGE	experimental_method	(A) SDS PAGE analysis of the purified Arabidopsis thaliana HAESA ectodomain (residues 20–620) obtained by secreted expression in insect cells.	FIG
38	58	Arabidopsis thaliana	species	(A) SDS PAGE analysis of the purified Arabidopsis thaliana HAESA ectodomain (residues 20–620) obtained by secreted expression in insect cells.	FIG
59	64	HAESA	protein	(A) SDS PAGE analysis of the purified Arabidopsis thaliana HAESA ectodomain (residues 20–620) obtained by secreted expression in insect cells.	FIG
65	75	ectodomain	structure_element	(A) SDS PAGE analysis of the purified Arabidopsis thaliana HAESA ectodomain (residues 20–620) obtained by secreted expression in insect cells.	FIG
86	92	20–620	residue_range	(A) SDS PAGE analysis of the purified Arabidopsis thaliana HAESA ectodomain (residues 20–620) obtained by secreted expression in insect cells.	FIG
106	141	secreted expression in insect cells	experimental_method	(A) SDS PAGE analysis of the purified Arabidopsis thaliana HAESA ectodomain (residues 20–620) obtained by secreted expression in insect cells.	FIG
81	98	mass spectrometry	experimental_method	The calculated molecular mass is 65.7 kDa, the actual molecular mass obtained by mass spectrometry is 74,896 Da, accounting for the N-glycans. (B) Ribbon diagrams showing front (left panel) and side views (right panel) of the isolated HAESA LRR domain.	FIG
132	141	N-glycans	chemical	The calculated molecular mass is 65.7 kDa, the actual molecular mass obtained by mass spectrometry is 74,896 Da, accounting for the N-glycans. (B) Ribbon diagrams showing front (left panel) and side views (right panel) of the isolated HAESA LRR domain.	FIG
235	240	HAESA	protein	The calculated molecular mass is 65.7 kDa, the actual molecular mass obtained by mass spectrometry is 74,896 Da, accounting for the N-glycans. (B) Ribbon diagrams showing front (left panel) and side views (right panel) of the isolated HAESA LRR domain.	FIG
241	251	LRR domain	structure_element	The calculated molecular mass is 65.7 kDa, the actual molecular mass obtained by mass spectrometry is 74,896 Da, accounting for the N-glycans. (B) Ribbon diagrams showing front (left panel) and side views (right panel) of the isolated HAESA LRR domain.	FIG
17	22	20–88	residue_range	The N- (residues 20–88) and C-terminal (residues 593–615) capping domains are shown in yellow, the central 21 LRR motifs are in blue and disulphide bonds are highlighted in green (in bonds representation). (C) Structure based sequence alignment of the 21 leucine-rich repeats in HAESA with the plant LRR consensus sequence shown for comparison.	FIG
49	56	593–615	residue_range	The N- (residues 20–88) and C-terminal (residues 593–615) capping domains are shown in yellow, the central 21 LRR motifs are in blue and disulphide bonds are highlighted in green (in bonds representation). (C) Structure based sequence alignment of the 21 leucine-rich repeats in HAESA with the plant LRR consensus sequence shown for comparison.	FIG
58	73	capping domains	structure_element	The N- (residues 20–88) and C-terminal (residues 593–615) capping domains are shown in yellow, the central 21 LRR motifs are in blue and disulphide bonds are highlighted in green (in bonds representation). (C) Structure based sequence alignment of the 21 leucine-rich repeats in HAESA with the plant LRR consensus sequence shown for comparison.	FIG
110	120	LRR motifs	structure_element	The N- (residues 20–88) and C-terminal (residues 593–615) capping domains are shown in yellow, the central 21 LRR motifs are in blue and disulphide bonds are highlighted in green (in bonds representation). (C) Structure based sequence alignment of the 21 leucine-rich repeats in HAESA with the plant LRR consensus sequence shown for comparison.	FIG
137	153	disulphide bonds	ptm	The N- (residues 20–88) and C-terminal (residues 593–615) capping domains are shown in yellow, the central 21 LRR motifs are in blue and disulphide bonds are highlighted in green (in bonds representation). (C) Structure based sequence alignment of the 21 leucine-rich repeats in HAESA with the plant LRR consensus sequence shown for comparison.	FIG
210	244	Structure based sequence alignment	experimental_method	The N- (residues 20–88) and C-terminal (residues 593–615) capping domains are shown in yellow, the central 21 LRR motifs are in blue and disulphide bonds are highlighted in green (in bonds representation). (C) Structure based sequence alignment of the 21 leucine-rich repeats in HAESA with the plant LRR consensus sequence shown for comparison.	FIG
255	275	leucine-rich repeats	structure_element	The N- (residues 20–88) and C-terminal (residues 593–615) capping domains are shown in yellow, the central 21 LRR motifs are in blue and disulphide bonds are highlighted in green (in bonds representation). (C) Structure based sequence alignment of the 21 leucine-rich repeats in HAESA with the plant LRR consensus sequence shown for comparison.	FIG
279	284	HAESA	protein	The N- (residues 20–88) and C-terminal (residues 593–615) capping domains are shown in yellow, the central 21 LRR motifs are in blue and disulphide bonds are highlighted in green (in bonds representation). (C) Structure based sequence alignment of the 21 leucine-rich repeats in HAESA with the plant LRR consensus sequence shown for comparison.	FIG
294	299	plant	taxonomy_domain	The N- (residues 20–88) and C-terminal (residues 593–615) capping domains are shown in yellow, the central 21 LRR motifs are in blue and disulphide bonds are highlighted in green (in bonds representation). (C) Structure based sequence alignment of the 21 leucine-rich repeats in HAESA with the plant LRR consensus sequence shown for comparison.	FIG
300	303	LRR	structure_element	The N- (residues 20–88) and C-terminal (residues 593–615) capping domains are shown in yellow, the central 21 LRR motifs are in blue and disulphide bonds are highlighted in green (in bonds representation). (C) Structure based sequence alignment of the 21 leucine-rich repeats in HAESA with the plant LRR consensus sequence shown for comparison.	FIG
0	9	Conserved	protein_state	Conserved hydrophobic residues are shaded in gray, N-glycosylation sites visible in our structures are highlighted in blue, cysteine residues involved in disulphide bridge formation in green. (D) Asn-linked glycans mask the N-terminal portion of the HAESA ectodomain.	FIG
10	21	hydrophobic	protein_state	Conserved hydrophobic residues are shaded in gray, N-glycosylation sites visible in our structures are highlighted in blue, cysteine residues involved in disulphide bridge formation in green. (D) Asn-linked glycans mask the N-terminal portion of the HAESA ectodomain.	FIG
22	30	residues	structure_element	Conserved hydrophobic residues are shaded in gray, N-glycosylation sites visible in our structures are highlighted in blue, cysteine residues involved in disulphide bridge formation in green. (D) Asn-linked glycans mask the N-terminal portion of the HAESA ectodomain.	FIG
51	72	N-glycosylation sites	site	Conserved hydrophobic residues are shaded in gray, N-glycosylation sites visible in our structures are highlighted in blue, cysteine residues involved in disulphide bridge formation in green. (D) Asn-linked glycans mask the N-terminal portion of the HAESA ectodomain.	FIG
88	98	structures	evidence	Conserved hydrophobic residues are shaded in gray, N-glycosylation sites visible in our structures are highlighted in blue, cysteine residues involved in disulphide bridge formation in green. (D) Asn-linked glycans mask the N-terminal portion of the HAESA ectodomain.	FIG
124	132	cysteine	residue_name	Conserved hydrophobic residues are shaded in gray, N-glycosylation sites visible in our structures are highlighted in blue, cysteine residues involved in disulphide bridge formation in green. (D) Asn-linked glycans mask the N-terminal portion of the HAESA ectodomain.	FIG
154	171	disulphide bridge	ptm	Conserved hydrophobic residues are shaded in gray, N-glycosylation sites visible in our structures are highlighted in blue, cysteine residues involved in disulphide bridge formation in green. (D) Asn-linked glycans mask the N-terminal portion of the HAESA ectodomain.	FIG
196	214	Asn-linked glycans	ptm	Conserved hydrophobic residues are shaded in gray, N-glycosylation sites visible in our structures are highlighted in blue, cysteine residues involved in disulphide bridge formation in green. (D) Asn-linked glycans mask the N-terminal portion of the HAESA ectodomain.	FIG
250	255	HAESA	protein	Conserved hydrophobic residues are shaded in gray, N-glycosylation sites visible in our structures are highlighted in blue, cysteine residues involved in disulphide bridge formation in green. (D) Asn-linked glycans mask the N-terminal portion of the HAESA ectodomain.	FIG
256	266	ectodomain	structure_element	Conserved hydrophobic residues are shaded in gray, N-glycosylation sites visible in our structures are highlighted in blue, cysteine residues involved in disulphide bridge formation in green. (D) Asn-linked glycans mask the N-terminal portion of the HAESA ectodomain.	FIG
0	12	Oligomannose	chemical	Oligomannose core structures (containing two N-actylglucosamines and three terminal mannose units) as found in Trichoplusia ni cells and in plants were modeled onto the seven glycosylation sites observed in our HAESA structures, to visualize the surface areas potentially not masked by carbohydrate.	FIG
45	64	N-actylglucosamines	chemical	Oligomannose core structures (containing two N-actylglucosamines and three terminal mannose units) as found in Trichoplusia ni cells and in plants were modeled onto the seven glycosylation sites observed in our HAESA structures, to visualize the surface areas potentially not masked by carbohydrate.	FIG
84	91	mannose	chemical	Oligomannose core structures (containing two N-actylglucosamines and three terminal mannose units) as found in Trichoplusia ni cells and in plants were modeled onto the seven glycosylation sites observed in our HAESA structures, to visualize the surface areas potentially not masked by carbohydrate.	FIG
111	126	Trichoplusia ni	species	Oligomannose core structures (containing two N-actylglucosamines and three terminal mannose units) as found in Trichoplusia ni cells and in plants were modeled onto the seven glycosylation sites observed in our HAESA structures, to visualize the surface areas potentially not masked by carbohydrate.	FIG
140	146	plants	taxonomy_domain	Oligomannose core structures (containing two N-actylglucosamines and three terminal mannose units) as found in Trichoplusia ni cells and in plants were modeled onto the seven glycosylation sites observed in our HAESA structures, to visualize the surface areas potentially not masked by carbohydrate.	FIG
175	194	glycosylation sites	site	Oligomannose core structures (containing two N-actylglucosamines and three terminal mannose units) as found in Trichoplusia ni cells and in plants were modeled onto the seven glycosylation sites observed in our HAESA structures, to visualize the surface areas potentially not masked by carbohydrate.	FIG
211	216	HAESA	protein	Oligomannose core structures (containing two N-actylglucosamines and three terminal mannose units) as found in Trichoplusia ni cells and in plants were modeled onto the seven glycosylation sites observed in our HAESA structures, to visualize the surface areas potentially not masked by carbohydrate.	FIG
217	227	structures	evidence	Oligomannose core structures (containing two N-actylglucosamines and three terminal mannose units) as found in Trichoplusia ni cells and in plants were modeled onto the seven glycosylation sites observed in our HAESA structures, to visualize the surface areas potentially not masked by carbohydrate.	FIG
286	298	carbohydrate	chemical	Oligomannose core structures (containing two N-actylglucosamines and three terminal mannose units) as found in Trichoplusia ni cells and in plants were modeled onto the seven glycosylation sites observed in our HAESA structures, to visualize the surface areas potentially not masked by carbohydrate.	FIG
4	9	HAESA	protein	The HAESA ectodomain is shown in blue (in surface representation), the glycan structures are shown in yellow.	FIG
10	20	ectodomain	structure_element	The HAESA ectodomain is shown in blue (in surface representation), the glycan structures are shown in yellow.	FIG
71	77	glycan	chemical	The HAESA ectodomain is shown in blue (in surface representation), the glycan structures are shown in yellow.	FIG
0	20	Hydrophobic contacts	bond_interaction	Hydrophobic contacts and a hydrogen-bond network mediate the interaction between HAESA and the peptide hormone IDA.	FIG
27	48	hydrogen-bond network	site	Hydrophobic contacts and a hydrogen-bond network mediate the interaction between HAESA and the peptide hormone IDA.	FIG
81	86	HAESA	protein	Hydrophobic contacts and a hydrogen-bond network mediate the interaction between HAESA and the peptide hormone IDA.	FIG
95	110	peptide hormone	protein_type	Hydrophobic contacts and a hydrogen-bond network mediate the interaction between HAESA and the peptide hormone IDA.	FIG
111	114	IDA	protein	Hydrophobic contacts and a hydrogen-bond network mediate the interaction between HAESA and the peptide hormone IDA.	FIG
19	37	IDA binding pocket	site	(A) Details of the IDA binding pocket.	FIG
0	5	HAESA	protein	HAESA is shown in blue (ribbon diagram), the C-terminal Arg-His-Asn motif (left panel), the central Hyp anchor (center) and the N-terminal Pro-rich motif in IDA (right panel) are shown in yellow (in bonds representation).	FIG
56	73	Arg-His-Asn motif	structure_element	HAESA is shown in blue (ribbon diagram), the C-terminal Arg-His-Asn motif (left panel), the central Hyp anchor (center) and the N-terminal Pro-rich motif in IDA (right panel) are shown in yellow (in bonds representation).	FIG
100	110	Hyp anchor	structure_element	HAESA is shown in blue (ribbon diagram), the C-terminal Arg-His-Asn motif (left panel), the central Hyp anchor (center) and the N-terminal Pro-rich motif in IDA (right panel) are shown in yellow (in bonds representation).	FIG
139	153	Pro-rich motif	structure_element	HAESA is shown in blue (ribbon diagram), the C-terminal Arg-His-Asn motif (left panel), the central Hyp anchor (center) and the N-terminal Pro-rich motif in IDA (right panel) are shown in yellow (in bonds representation).	FIG
157	160	IDA	protein	HAESA is shown in blue (ribbon diagram), the C-terminal Arg-His-Asn motif (left panel), the central Hyp anchor (center) and the N-terminal Pro-rich motif in IDA (right panel) are shown in yellow (in bonds representation).	FIG
0	24	HAESA interface residues	site	HAESA interface residues are shown as sticks, selected hydrogen bond interactions are denoted as dotted lines (in magenta). (B) View of the complete IDA (in bonds representation, in yellow) binding pocket in HAESA (surface view, in blue).	FIG
55	81	hydrogen bond interactions	bond_interaction	HAESA interface residues are shown as sticks, selected hydrogen bond interactions are denoted as dotted lines (in magenta). (B) View of the complete IDA (in bonds representation, in yellow) binding pocket in HAESA (surface view, in blue).	FIG
149	152	IDA	protein	HAESA interface residues are shown as sticks, selected hydrogen bond interactions are denoted as dotted lines (in magenta). (B) View of the complete IDA (in bonds representation, in yellow) binding pocket in HAESA (surface view, in blue).	FIG
190	204	binding pocket	site	HAESA interface residues are shown as sticks, selected hydrogen bond interactions are denoted as dotted lines (in magenta). (B) View of the complete IDA (in bonds representation, in yellow) binding pocket in HAESA (surface view, in blue).	FIG
208	213	HAESA	protein	HAESA interface residues are shown as sticks, selected hydrogen bond interactions are denoted as dotted lines (in magenta). (B) View of the complete IDA (in bonds representation, in yellow) binding pocket in HAESA (surface view, in blue).	FIG
27	61	Structure based sequence alignment	experimental_method	Orientation as in (A). (C) Structure based sequence alignment of leucine-rich repeats in HAESA with the plant LRR consensus sequence shown for comparison.	FIG
65	85	leucine-rich repeats	structure_element	Orientation as in (A). (C) Structure based sequence alignment of leucine-rich repeats in HAESA with the plant LRR consensus sequence shown for comparison.	FIG
89	94	HAESA	protein	Orientation as in (A). (C) Structure based sequence alignment of leucine-rich repeats in HAESA with the plant LRR consensus sequence shown for comparison.	FIG
104	109	plant	taxonomy_domain	Orientation as in (A). (C) Structure based sequence alignment of leucine-rich repeats in HAESA with the plant LRR consensus sequence shown for comparison.	FIG
110	113	LRR	structure_element	Orientation as in (A). (C) Structure based sequence alignment of leucine-rich repeats in HAESA with the plant LRR consensus sequence shown for comparison.	FIG
114	132	consensus sequence	evidence	Orientation as in (A). (C) Structure based sequence alignment of leucine-rich repeats in HAESA with the plant LRR consensus sequence shown for comparison.	FIG
19	43	hydrophobic interactions	bond_interaction	Residues mediating hydrophobic interactions with the IDA peptide are highlighted in blue, residues contributing to hydrogen bond interactions and/or salt bridges are shown in red.	FIG
53	64	IDA peptide	chemical	Residues mediating hydrophobic interactions with the IDA peptide are highlighted in blue, residues contributing to hydrogen bond interactions and/or salt bridges are shown in red.	FIG
115	141	hydrogen bond interactions	bond_interaction	Residues mediating hydrophobic interactions with the IDA peptide are highlighted in blue, residues contributing to hydrogen bond interactions and/or salt bridges are shown in red.	FIG
149	161	salt bridges	bond_interaction	Residues mediating hydrophobic interactions with the IDA peptide are highlighted in blue, residues contributing to hydrogen bond interactions and/or salt bridges are shown in red.	FIG
4	22	IDA binding pocket	site	The IDA binding pocket covers LRRs 2–14 and all residues originate from the inner surface of the HAESA superhelix.	FIG
30	39	LRRs 2–14	structure_element	The IDA binding pocket covers LRRs 2–14 and all residues originate from the inner surface of the HAESA superhelix.	FIG
97	102	HAESA	protein	The IDA binding pocket covers LRRs 2–14 and all residues originate from the inner surface of the HAESA superhelix.	FIG
103	113	superhelix	structure_element	The IDA binding pocket covers LRRs 2–14 and all residues originate from the inner surface of the HAESA superhelix.	FIG
4	13	IDA-HAESA	complex_assembly	The IDA-HAESA and SERK1-HAESA complex interfaces are conserved among HAESA and HAESA-like proteins from different plant species.	FIG
18	29	SERK1-HAESA	complex_assembly	The IDA-HAESA and SERK1-HAESA complex interfaces are conserved among HAESA and HAESA-like proteins from different plant species.	FIG
38	48	interfaces	site	The IDA-HAESA and SERK1-HAESA complex interfaces are conserved among HAESA and HAESA-like proteins from different plant species.	FIG
53	62	conserved	protein_state	The IDA-HAESA and SERK1-HAESA complex interfaces are conserved among HAESA and HAESA-like proteins from different plant species.	FIG
69	74	HAESA	protein	The IDA-HAESA and SERK1-HAESA complex interfaces are conserved among HAESA and HAESA-like proteins from different plant species.	FIG
79	98	HAESA-like proteins	protein_type	The IDA-HAESA and SERK1-HAESA complex interfaces are conserved among HAESA and HAESA-like proteins from different plant species.	FIG
114	119	plant	taxonomy_domain	The IDA-HAESA and SERK1-HAESA complex interfaces are conserved among HAESA and HAESA-like proteins from different plant species.	FIG
0	34	Structure-based sequence alignment	experimental_method	Structure-based sequence alignment of the HAESA family members: Arabidopsis thaliana HAESA (Uniprot (http://www.uniprot.org) ID P47735), Arabidopsis thaliana HSL2 (Uniprot ID C0LGX3), Capsella rubella HAESA (Uniprot ID R0F2U6), Citrus clementina HSL2 (Uniprot ID V4U227), Vitis vinifera HAESA (Uniprot ID F6HM39).	FIG
42	62	HAESA family members	protein_type	Structure-based sequence alignment of the HAESA family members: Arabidopsis thaliana HAESA (Uniprot (http://www.uniprot.org) ID P47735), Arabidopsis thaliana HSL2 (Uniprot ID C0LGX3), Capsella rubella HAESA (Uniprot ID R0F2U6), Citrus clementina HSL2 (Uniprot ID V4U227), Vitis vinifera HAESA (Uniprot ID F6HM39).	FIG
64	84	Arabidopsis thaliana	species	Structure-based sequence alignment of the HAESA family members: Arabidopsis thaliana HAESA (Uniprot (http://www.uniprot.org) ID P47735), Arabidopsis thaliana HSL2 (Uniprot ID C0LGX3), Capsella rubella HAESA (Uniprot ID R0F2U6), Citrus clementina HSL2 (Uniprot ID V4U227), Vitis vinifera HAESA (Uniprot ID F6HM39).	FIG
85	90	HAESA	protein	Structure-based sequence alignment of the HAESA family members: Arabidopsis thaliana HAESA (Uniprot (http://www.uniprot.org) ID P47735), Arabidopsis thaliana HSL2 (Uniprot ID C0LGX3), Capsella rubella HAESA (Uniprot ID R0F2U6), Citrus clementina HSL2 (Uniprot ID V4U227), Vitis vinifera HAESA (Uniprot ID F6HM39).	FIG
137	157	Arabidopsis thaliana	species	Structure-based sequence alignment of the HAESA family members: Arabidopsis thaliana HAESA (Uniprot (http://www.uniprot.org) ID P47735), Arabidopsis thaliana HSL2 (Uniprot ID C0LGX3), Capsella rubella HAESA (Uniprot ID R0F2U6), Citrus clementina HSL2 (Uniprot ID V4U227), Vitis vinifera HAESA (Uniprot ID F6HM39).	FIG
158	162	HSL2	protein	Structure-based sequence alignment of the HAESA family members: Arabidopsis thaliana HAESA (Uniprot (http://www.uniprot.org) ID P47735), Arabidopsis thaliana HSL2 (Uniprot ID C0LGX3), Capsella rubella HAESA (Uniprot ID R0F2U6), Citrus clementina HSL2 (Uniprot ID V4U227), Vitis vinifera HAESA (Uniprot ID F6HM39).	FIG
184	200	Capsella rubella	species	Structure-based sequence alignment of the HAESA family members: Arabidopsis thaliana HAESA (Uniprot (http://www.uniprot.org) ID P47735), Arabidopsis thaliana HSL2 (Uniprot ID C0LGX3), Capsella rubella HAESA (Uniprot ID R0F2U6), Citrus clementina HSL2 (Uniprot ID V4U227), Vitis vinifera HAESA (Uniprot ID F6HM39).	FIG
201	206	HAESA	protein	Structure-based sequence alignment of the HAESA family members: Arabidopsis thaliana HAESA (Uniprot (http://www.uniprot.org) ID P47735), Arabidopsis thaliana HSL2 (Uniprot ID C0LGX3), Capsella rubella HAESA (Uniprot ID R0F2U6), Citrus clementina HSL2 (Uniprot ID V4U227), Vitis vinifera HAESA (Uniprot ID F6HM39).	FIG
228	245	Citrus clementina	species	Structure-based sequence alignment of the HAESA family members: Arabidopsis thaliana HAESA (Uniprot (http://www.uniprot.org) ID P47735), Arabidopsis thaliana HSL2 (Uniprot ID C0LGX3), Capsella rubella HAESA (Uniprot ID R0F2U6), Citrus clementina HSL2 (Uniprot ID V4U227), Vitis vinifera HAESA (Uniprot ID F6HM39).	FIG
246	250	HSL2	protein	Structure-based sequence alignment of the HAESA family members: Arabidopsis thaliana HAESA (Uniprot (http://www.uniprot.org) ID P47735), Arabidopsis thaliana HSL2 (Uniprot ID C0LGX3), Capsella rubella HAESA (Uniprot ID R0F2U6), Citrus clementina HSL2 (Uniprot ID V4U227), Vitis vinifera HAESA (Uniprot ID F6HM39).	FIG
272	286	Vitis vinifera	species	Structure-based sequence alignment of the HAESA family members: Arabidopsis thaliana HAESA (Uniprot (http://www.uniprot.org) ID P47735), Arabidopsis thaliana HSL2 (Uniprot ID C0LGX3), Capsella rubella HAESA (Uniprot ID R0F2U6), Citrus clementina HSL2 (Uniprot ID V4U227), Vitis vinifera HAESA (Uniprot ID F6HM39).	FIG
287	292	HAESA	protein	Structure-based sequence alignment of the HAESA family members: Arabidopsis thaliana HAESA (Uniprot (http://www.uniprot.org) ID P47735), Arabidopsis thaliana HSL2 (Uniprot ID C0LGX3), Capsella rubella HAESA (Uniprot ID R0F2U6), Citrus clementina HSL2 (Uniprot ID V4U227), Vitis vinifera HAESA (Uniprot ID F6HM39).	FIG
151	155	caps	structure_element	The alignment includes a secondary structure assignment calculated with the program DSSP and colored according to Figure 1, with the N- and C-terminal caps and the 21 LRR motifs indicated in orange and blue, respectively.	FIG
167	177	LRR motifs	structure_element	The alignment includes a secondary structure assignment calculated with the program DSSP and colored according to Figure 1, with the N- and C-terminal caps and the 21 LRR motifs indicated in orange and blue, respectively.	FIG
0	8	Cysteine	residue_name	Cysteine residues engaged in disulphide bonds are depicted in green.	FIG
29	45	disulphide bonds	ptm	Cysteine residues engaged in disulphide bonds are depicted in green.	FIG
0	5	HAESA	protein	HAESA residues interacting with the IDA peptide and/or the SERK1 co-receptor kinase ectodomain are highlighted in blue and orange, respectively.	FIG
36	47	IDA peptide	chemical	HAESA residues interacting with the IDA peptide and/or the SERK1 co-receptor kinase ectodomain are highlighted in blue and orange, respectively.	FIG
59	64	SERK1	protein	HAESA residues interacting with the IDA peptide and/or the SERK1 co-receptor kinase ectodomain are highlighted in blue and orange, respectively.	FIG
65	83	co-receptor kinase	protein_type	HAESA residues interacting with the IDA peptide and/or the SERK1 co-receptor kinase ectodomain are highlighted in blue and orange, respectively.	FIG
84	94	ectodomain	structure_element	HAESA residues interacting with the IDA peptide and/or the SERK1 co-receptor kinase ectodomain are highlighted in blue and orange, respectively.	FIG
4	19	peptide hormone	protein_type	The peptide hormone IDA binds to the HAESA LRR ectodomain.	FIG
20	23	IDA	protein	The peptide hormone IDA binds to the HAESA LRR ectodomain.	FIG
37	42	HAESA	protein	The peptide hormone IDA binds to the HAESA LRR ectodomain.	FIG
43	57	LRR ectodomain	structure_element	The peptide hormone IDA binds to the HAESA LRR ectodomain.	FIG
4	31	Multiple sequence alignment	experimental_method	(A) Multiple sequence alignment of selected IDA family members.	FIG
44	62	IDA family members	protein_type	(A) Multiple sequence alignment of selected IDA family members.	FIG
4	13	conserved	protein_state	The conserved PIP motif is highlighted in yellow, the central Hyp in blue.	FIG
14	23	PIP motif	structure_element	The conserved PIP motif is highlighted in yellow, the central Hyp in blue.	FIG
62	65	Hyp	residue_name	The conserved PIP motif is highlighted in yellow, the central Hyp in blue.	FIG
4	14	PKGV motif	structure_element	The PKGV motif present in our N-terminally extended IDA peptide is highlighted in red. (B) Isothermal titration calorimetry of the HAESA ectodomain vs. IDA and including the synthetic peptide sequence.	FIG
30	51	N-terminally extended	protein_state	The PKGV motif present in our N-terminally extended IDA peptide is highlighted in red. (B) Isothermal titration calorimetry of the HAESA ectodomain vs. IDA and including the synthetic peptide sequence.	FIG
52	63	IDA peptide	chemical	The PKGV motif present in our N-terminally extended IDA peptide is highlighted in red. (B) Isothermal titration calorimetry of the HAESA ectodomain vs. IDA and including the synthetic peptide sequence.	FIG
91	123	Isothermal titration calorimetry	experimental_method	The PKGV motif present in our N-terminally extended IDA peptide is highlighted in red. (B) Isothermal titration calorimetry of the HAESA ectodomain vs. IDA and including the synthetic peptide sequence.	FIG
131	136	HAESA	protein	The PKGV motif present in our N-terminally extended IDA peptide is highlighted in red. (B) Isothermal titration calorimetry of the HAESA ectodomain vs. IDA and including the synthetic peptide sequence.	FIG
137	147	ectodomain	structure_element	The PKGV motif present in our N-terminally extended IDA peptide is highlighted in red. (B) Isothermal titration calorimetry of the HAESA ectodomain vs. IDA and including the synthetic peptide sequence.	FIG
152	155	IDA	protein	The PKGV motif present in our N-terminally extended IDA peptide is highlighted in red. (B) Isothermal titration calorimetry of the HAESA ectodomain vs. IDA and including the synthetic peptide sequence.	FIG
174	183	synthetic	protein_state	The PKGV motif present in our N-terminally extended IDA peptide is highlighted in red. (B) Isothermal titration calorimetry of the HAESA ectodomain vs. IDA and including the synthetic peptide sequence.	FIG
184	191	peptide	chemical	The PKGV motif present in our N-terminally extended IDA peptide is highlighted in red. (B) Isothermal titration calorimetry of the HAESA ectodomain vs. IDA and including the synthetic peptide sequence.	FIG
21	32	HAESA – IDA	complex_assembly	(C) Structure of the HAESA – IDA complex with HAESA shown in blue (ribbon diagram).	FIG
46	51	HAESA	protein	(C) Structure of the HAESA – IDA complex with HAESA shown in blue (ribbon diagram).	FIG
0	3	IDA	protein	IDA (in bonds representation, surface view included) is depicted in yellow.	FIG
4	26	peptide binding pocket	site	The peptide binding pocket covers HAESA LRRs 2–14. (D) Close-up view of the entire IDA (in yellow) peptide binding site in HAESA (in blue).	FIG
34	39	HAESA	protein	The peptide binding pocket covers HAESA LRRs 2–14. (D) Close-up view of the entire IDA (in yellow) peptide binding site in HAESA (in blue).	FIG
40	49	LRRs 2–14	structure_element	The peptide binding pocket covers HAESA LRRs 2–14. (D) Close-up view of the entire IDA (in yellow) peptide binding site in HAESA (in blue).	FIG
83	86	IDA	protein	The peptide binding pocket covers HAESA LRRs 2–14. (D) Close-up view of the entire IDA (in yellow) peptide binding site in HAESA (in blue).	FIG
99	119	peptide binding site	site	The peptide binding pocket covers HAESA LRRs 2–14. (D) Close-up view of the entire IDA (in yellow) peptide binding site in HAESA (in blue).	FIG
123	128	HAESA	protein	The peptide binding pocket covers HAESA LRRs 2–14. (D) Close-up view of the entire IDA (in yellow) peptide binding site in HAESA (in blue).	FIG
48	58	Hyp anchor	structure_element	Details of the interactions between the central Hyp anchor in IDA and the C-terminal Arg-His-Asn motif with HAESA are highlighted in (E) and (F), respectively.	FIG
62	65	IDA	protein	Details of the interactions between the central Hyp anchor in IDA and the C-terminal Arg-His-Asn motif with HAESA are highlighted in (E) and (F), respectively.	FIG
85	102	Arg-His-Asn motif	structure_element	Details of the interactions between the central Hyp anchor in IDA and the C-terminal Arg-His-Asn motif with HAESA are highlighted in (E) and (F), respectively.	FIG
108	113	HAESA	protein	Details of the interactions between the central Hyp anchor in IDA and the C-terminal Arg-His-Asn motif with HAESA are highlighted in (E) and (F), respectively.	FIG
61	66	water	chemical	Hydrogren bonds are depicted as dotted lines (in magenta), a water molecule is shown as a red sphere.	FIG
50	56	plants	taxonomy_domain	During their growth, development and reproduction plants use cell separation processes to detach no-longer required, damaged or senescent organs.	INTRO
31	42	Arabidopsis	taxonomy_domain	Abscission of floral organs in Arabidopsis is a model system to study these cell separation processes in molecular detail.	INTRO
4	11	LRR-RKs	structure_element	The LRR-RKs HAESA (greek: to adhere to) and HAESA-LIKE 2 (HSL2) redundantly control floral abscission.	INTRO
12	17	HAESA	protein	The LRR-RKs HAESA (greek: to adhere to) and HAESA-LIKE 2 (HSL2) redundantly control floral abscission.	INTRO
44	56	HAESA-LIKE 2	protein	The LRR-RKs HAESA (greek: to adhere to) and HAESA-LIKE 2 (HSL2) redundantly control floral abscission.	INTRO
58	62	HSL2	protein	The LRR-RKs HAESA (greek: to adhere to) and HAESA-LIKE 2 (HSL2) redundantly control floral abscission.	INTRO
47	84	INFLORESCENCE DEFICIENT IN ABSCISSION	protein	Loss-of-function of the secreted small protein INFLORESCENCE DEFICIENT IN ABSCISSION (IDA) causes floral organs to remain attached while its over-expression leads to premature shedding.	INTRO
86	89	IDA	protein	Loss-of-function of the secreted small protein INFLORESCENCE DEFICIENT IN ABSCISSION (IDA) causes floral organs to remain attached while its over-expression leads to premature shedding.	INTRO
0	11	Full-length	protein_state	Full-length IDA is proteolytically processed and a conserved stretch of 20 amino-acids (termed EPIP) can rescue the IDA loss-of-function phenotype (Figure 1A).	INTRO
12	15	IDA	protein	Full-length IDA is proteolytically processed and a conserved stretch of 20 amino-acids (termed EPIP) can rescue the IDA loss-of-function phenotype (Figure 1A).	INTRO
19	44	proteolytically processed	ptm	Full-length IDA is proteolytically processed and a conserved stretch of 20 amino-acids (termed EPIP) can rescue the IDA loss-of-function phenotype (Figure 1A).	INTRO
51	60	conserved	protein_state	Full-length IDA is proteolytically processed and a conserved stretch of 20 amino-acids (termed EPIP) can rescue the IDA loss-of-function phenotype (Figure 1A).	INTRO
61	86	stretch of 20 amino-acids	residue_range	Full-length IDA is proteolytically processed and a conserved stretch of 20 amino-acids (termed EPIP) can rescue the IDA loss-of-function phenotype (Figure 1A).	INTRO
95	99	EPIP	structure_element	Full-length IDA is proteolytically processed and a conserved stretch of 20 amino-acids (termed EPIP) can rescue the IDA loss-of-function phenotype (Figure 1A).	INTRO
116	119	IDA	protein	Full-length IDA is proteolytically processed and a conserved stretch of 20 amino-acids (termed EPIP) can rescue the IDA loss-of-function phenotype (Figure 1A).	INTRO
32	41	dodecamer	structure_element	It has been demonstrated that a dodecamer peptide within EPIP is able to activate HAESA and HSL2 in transient assays in tobacco cells.	INTRO
42	49	peptide	chemical	It has been demonstrated that a dodecamer peptide within EPIP is able to activate HAESA and HSL2 in transient assays in tobacco cells.	INTRO
57	61	EPIP	structure_element	It has been demonstrated that a dodecamer peptide within EPIP is able to activate HAESA and HSL2 in transient assays in tobacco cells.	INTRO
82	87	HAESA	protein	It has been demonstrated that a dodecamer peptide within EPIP is able to activate HAESA and HSL2 in transient assays in tobacco cells.	INTRO
92	96	HSL2	protein	It has been demonstrated that a dodecamer peptide within EPIP is able to activate HAESA and HSL2 in transient assays in tobacco cells.	INTRO
100	116	transient assays	experimental_method	It has been demonstrated that a dodecamer peptide within EPIP is able to activate HAESA and HSL2 in transient assays in tobacco cells.	INTRO
120	127	tobacco	taxonomy_domain	It has been demonstrated that a dodecamer peptide within EPIP is able to activate HAESA and HSL2 in transient assays in tobacco cells.	INTRO
0	19	This sequence motif	structure_element	This sequence motif is highly conserved among IDA family members (IDA-LIKE PROTEINS, IDLs) and contains a central Pro residue, presumed to be post-translationally modified to hydroxyproline (Hyp; Figure 1A).	INTRO
23	39	highly conserved	protein_state	This sequence motif is highly conserved among IDA family members (IDA-LIKE PROTEINS, IDLs) and contains a central Pro residue, presumed to be post-translationally modified to hydroxyproline (Hyp; Figure 1A).	INTRO
46	64	IDA family members	protein_type	This sequence motif is highly conserved among IDA family members (IDA-LIKE PROTEINS, IDLs) and contains a central Pro residue, presumed to be post-translationally modified to hydroxyproline (Hyp; Figure 1A).	INTRO
66	83	IDA-LIKE PROTEINS	protein_type	This sequence motif is highly conserved among IDA family members (IDA-LIKE PROTEINS, IDLs) and contains a central Pro residue, presumed to be post-translationally modified to hydroxyproline (Hyp; Figure 1A).	INTRO
85	89	IDLs	protein_type	This sequence motif is highly conserved among IDA family members (IDA-LIKE PROTEINS, IDLs) and contains a central Pro residue, presumed to be post-translationally modified to hydroxyproline (Hyp; Figure 1A).	INTRO
114	117	Pro	residue_name	This sequence motif is highly conserved among IDA family members (IDA-LIKE PROTEINS, IDLs) and contains a central Pro residue, presumed to be post-translationally modified to hydroxyproline (Hyp; Figure 1A).	INTRO
142	171	post-translationally modified	protein_state	This sequence motif is highly conserved among IDA family members (IDA-LIKE PROTEINS, IDLs) and contains a central Pro residue, presumed to be post-translationally modified to hydroxyproline (Hyp; Figure 1A).	INTRO
175	189	hydroxyproline	residue_name	This sequence motif is highly conserved among IDA family members (IDA-LIKE PROTEINS, IDLs) and contains a central Pro residue, presumed to be post-translationally modified to hydroxyproline (Hyp; Figure 1A).	INTRO
191	194	Hyp	residue_name	This sequence motif is highly conserved among IDA family members (IDA-LIKE PROTEINS, IDLs) and contains a central Pro residue, presumed to be post-translationally modified to hydroxyproline (Hyp; Figure 1A).	INTRO
61	64	IDA	protein	The available genetic and biochemical evidence suggests that IDA and HAESA together control floral abscission, but it is poorly understood if IDA is directly sensed by the receptor kinase HAESA and how IDA binding at the cell surface would activate the receptor.	INTRO
69	74	HAESA	protein	The available genetic and biochemical evidence suggests that IDA and HAESA together control floral abscission, but it is poorly understood if IDA is directly sensed by the receptor kinase HAESA and how IDA binding at the cell surface would activate the receptor.	INTRO
142	145	IDA	protein	The available genetic and biochemical evidence suggests that IDA and HAESA together control floral abscission, but it is poorly understood if IDA is directly sensed by the receptor kinase HAESA and how IDA binding at the cell surface would activate the receptor.	INTRO
172	187	receptor kinase	protein_type	The available genetic and biochemical evidence suggests that IDA and HAESA together control floral abscission, but it is poorly understood if IDA is directly sensed by the receptor kinase HAESA and how IDA binding at the cell surface would activate the receptor.	INTRO
188	193	HAESA	protein	The available genetic and biochemical evidence suggests that IDA and HAESA together control floral abscission, but it is poorly understood if IDA is directly sensed by the receptor kinase HAESA and how IDA binding at the cell surface would activate the receptor.	INTRO
202	205	IDA	protein	The available genetic and biochemical evidence suggests that IDA and HAESA together control floral abscission, but it is poorly understood if IDA is directly sensed by the receptor kinase HAESA and how IDA binding at the cell surface would activate the receptor.	INTRO
0	3	IDA	protein	IDA directly binds to the LRR domain of HAESA	RESULTS
26	36	LRR domain	structure_element	IDA directly binds to the LRR domain of HAESA	RESULTS
40	45	HAESA	protein	IDA directly binds to the LRR domain of HAESA	RESULTS
0	6	Active	protein_state	Active IDA-family peptide hormones are hydroxyprolinated dodecamers.	FIG
7	34	IDA-family peptide hormones	protein_type	Active IDA-family peptide hormones are hydroxyprolinated dodecamers.	FIG
39	56	hydroxyprolinated	protein_state	Active IDA-family peptide hormones are hydroxyprolinated dodecamers.	FIG
57	67	dodecamers	structure_element	Active IDA-family peptide hormones are hydroxyprolinated dodecamers.	FIG
22	25	IDA	protein	Close-up views of (A) IDA, (B) the N-terminally extended PKGV-IDA and (C) IDL1 bound to the HAESA hormone binding pocket (in bonds representation, in yellow) and including simulated annealing 2Fo–Fc omit electron density maps contoured at 1.0 σ.	FIG
35	56	N-terminally extended	protein_state	Close-up views of (A) IDA, (B) the N-terminally extended PKGV-IDA and (C) IDL1 bound to the HAESA hormone binding pocket (in bonds representation, in yellow) and including simulated annealing 2Fo–Fc omit electron density maps contoured at 1.0 σ.	FIG
57	65	PKGV-IDA	mutant	Close-up views of (A) IDA, (B) the N-terminally extended PKGV-IDA and (C) IDL1 bound to the HAESA hormone binding pocket (in bonds representation, in yellow) and including simulated annealing 2Fo–Fc omit electron density maps contoured at 1.0 σ.	FIG
74	78	IDL1	protein	Close-up views of (A) IDA, (B) the N-terminally extended PKGV-IDA and (C) IDL1 bound to the HAESA hormone binding pocket (in bonds representation, in yellow) and including simulated annealing 2Fo–Fc omit electron density maps contoured at 1.0 σ.	FIG
79	87	bound to	protein_state	Close-up views of (A) IDA, (B) the N-terminally extended PKGV-IDA and (C) IDL1 bound to the HAESA hormone binding pocket (in bonds representation, in yellow) and including simulated annealing 2Fo–Fc omit electron density maps contoured at 1.0 σ.	FIG
92	97	HAESA	protein	Close-up views of (A) IDA, (B) the N-terminally extended PKGV-IDA and (C) IDL1 bound to the HAESA hormone binding pocket (in bonds representation, in yellow) and including simulated annealing 2Fo–Fc omit electron density maps contoured at 1.0 σ.	FIG
98	120	hormone binding pocket	site	Close-up views of (A) IDA, (B) the N-terminally extended PKGV-IDA and (C) IDL1 bound to the HAESA hormone binding pocket (in bonds representation, in yellow) and including simulated annealing 2Fo–Fc omit electron density maps contoured at 1.0 σ.	FIG
172	191	simulated annealing	experimental_method	Close-up views of (A) IDA, (B) the N-terminally extended PKGV-IDA and (C) IDL1 bound to the HAESA hormone binding pocket (in bonds representation, in yellow) and including simulated annealing 2Fo–Fc omit electron density maps contoured at 1.0 σ.	FIG
192	225	2Fo–Fc omit electron density maps	evidence	Close-up views of (A) IDA, (B) the N-terminally extended PKGV-IDA and (C) IDL1 bound to the HAESA hormone binding pocket (in bonds representation, in yellow) and including simulated annealing 2Fo–Fc omit electron density maps contoured at 1.0 σ.	FIG
10	15	Pro58	residue_name_number	Note that Pro58IDA and Leu67IDA are the first residues defined by electron density when bound to the HAESA ectodomain. (D) Table summaries for equilibrium dissociation constants (Kd), binding enthalpies (ΔH), binding entropies (ΔS) and stoichoimetries (N) for different IDA peptides binding to the HAESA ectodomain ( ± fitting errors; n.d.	FIG
15	18	IDA	protein	Note that Pro58IDA and Leu67IDA are the first residues defined by electron density when bound to the HAESA ectodomain. (D) Table summaries for equilibrium dissociation constants (Kd), binding enthalpies (ΔH), binding entropies (ΔS) and stoichoimetries (N) for different IDA peptides binding to the HAESA ectodomain ( ± fitting errors; n.d.	FIG
23	28	Leu67	residue_name_number	Note that Pro58IDA and Leu67IDA are the first residues defined by electron density when bound to the HAESA ectodomain. (D) Table summaries for equilibrium dissociation constants (Kd), binding enthalpies (ΔH), binding entropies (ΔS) and stoichoimetries (N) for different IDA peptides binding to the HAESA ectodomain ( ± fitting errors; n.d.	FIG
28	31	IDA	protein	Note that Pro58IDA and Leu67IDA are the first residues defined by electron density when bound to the HAESA ectodomain. (D) Table summaries for equilibrium dissociation constants (Kd), binding enthalpies (ΔH), binding entropies (ΔS) and stoichoimetries (N) for different IDA peptides binding to the HAESA ectodomain ( ± fitting errors; n.d.	FIG
66	82	electron density	evidence	Note that Pro58IDA and Leu67IDA are the first residues defined by electron density when bound to the HAESA ectodomain. (D) Table summaries for equilibrium dissociation constants (Kd), binding enthalpies (ΔH), binding entropies (ΔS) and stoichoimetries (N) for different IDA peptides binding to the HAESA ectodomain ( ± fitting errors; n.d.	FIG
88	96	bound to	protein_state	Note that Pro58IDA and Leu67IDA are the first residues defined by electron density when bound to the HAESA ectodomain. (D) Table summaries for equilibrium dissociation constants (Kd), binding enthalpies (ΔH), binding entropies (ΔS) and stoichoimetries (N) for different IDA peptides binding to the HAESA ectodomain ( ± fitting errors; n.d.	FIG
101	106	HAESA	protein	Note that Pro58IDA and Leu67IDA are the first residues defined by electron density when bound to the HAESA ectodomain. (D) Table summaries for equilibrium dissociation constants (Kd), binding enthalpies (ΔH), binding entropies (ΔS) and stoichoimetries (N) for different IDA peptides binding to the HAESA ectodomain ( ± fitting errors; n.d.	FIG
107	117	ectodomain	structure_element	Note that Pro58IDA and Leu67IDA are the first residues defined by electron density when bound to the HAESA ectodomain. (D) Table summaries for equilibrium dissociation constants (Kd), binding enthalpies (ΔH), binding entropies (ΔS) and stoichoimetries (N) for different IDA peptides binding to the HAESA ectodomain ( ± fitting errors; n.d.	FIG
143	177	equilibrium dissociation constants	evidence	Note that Pro58IDA and Leu67IDA are the first residues defined by electron density when bound to the HAESA ectodomain. (D) Table summaries for equilibrium dissociation constants (Kd), binding enthalpies (ΔH), binding entropies (ΔS) and stoichoimetries (N) for different IDA peptides binding to the HAESA ectodomain ( ± fitting errors; n.d.	FIG
179	181	Kd	evidence	Note that Pro58IDA and Leu67IDA are the first residues defined by electron density when bound to the HAESA ectodomain. (D) Table summaries for equilibrium dissociation constants (Kd), binding enthalpies (ΔH), binding entropies (ΔS) and stoichoimetries (N) for different IDA peptides binding to the HAESA ectodomain ( ± fitting errors; n.d.	FIG
184	202	binding enthalpies	evidence	Note that Pro58IDA and Leu67IDA are the first residues defined by electron density when bound to the HAESA ectodomain. (D) Table summaries for equilibrium dissociation constants (Kd), binding enthalpies (ΔH), binding entropies (ΔS) and stoichoimetries (N) for different IDA peptides binding to the HAESA ectodomain ( ± fitting errors; n.d.	FIG
204	206	ΔH	evidence	Note that Pro58IDA and Leu67IDA are the first residues defined by electron density when bound to the HAESA ectodomain. (D) Table summaries for equilibrium dissociation constants (Kd), binding enthalpies (ΔH), binding entropies (ΔS) and stoichoimetries (N) for different IDA peptides binding to the HAESA ectodomain ( ± fitting errors; n.d.	FIG
209	226	binding entropies	evidence	Note that Pro58IDA and Leu67IDA are the first residues defined by electron density when bound to the HAESA ectodomain. (D) Table summaries for equilibrium dissociation constants (Kd), binding enthalpies (ΔH), binding entropies (ΔS) and stoichoimetries (N) for different IDA peptides binding to the HAESA ectodomain ( ± fitting errors; n.d.	FIG
228	230	ΔS	evidence	Note that Pro58IDA and Leu67IDA are the first residues defined by electron density when bound to the HAESA ectodomain. (D) Table summaries for equilibrium dissociation constants (Kd), binding enthalpies (ΔH), binding entropies (ΔS) and stoichoimetries (N) for different IDA peptides binding to the HAESA ectodomain ( ± fitting errors; n.d.	FIG
270	282	IDA peptides	chemical	Note that Pro58IDA and Leu67IDA are the first residues defined by electron density when bound to the HAESA ectodomain. (D) Table summaries for equilibrium dissociation constants (Kd), binding enthalpies (ΔH), binding entropies (ΔS) and stoichoimetries (N) for different IDA peptides binding to the HAESA ectodomain ( ± fitting errors; n.d.	FIG
298	303	HAESA	protein	Note that Pro58IDA and Leu67IDA are the first residues defined by electron density when bound to the HAESA ectodomain. (D) Table summaries for equilibrium dissociation constants (Kd), binding enthalpies (ΔH), binding entropies (ΔS) and stoichoimetries (N) for different IDA peptides binding to the HAESA ectodomain ( ± fitting errors; n.d.	FIG
304	314	ectodomain	structure_element	Note that Pro58IDA and Leu67IDA are the first residues defined by electron density when bound to the HAESA ectodomain. (D) Table summaries for equilibrium dissociation constants (Kd), binding enthalpies (ΔH), binding entropies (ΔS) and stoichoimetries (N) for different IDA peptides binding to the HAESA ectodomain ( ± fitting errors; n.d.	FIG
28	52	Structural superposition	experimental_method	no detectable binding). (E) Structural superposition of the active IDA (in bonds representation, in gray) and IDL1 peptide (in yellow) hormones bound to the HAESA ectodomain.	FIG
60	66	active	protein_state	no detectable binding). (E) Structural superposition of the active IDA (in bonds representation, in gray) and IDL1 peptide (in yellow) hormones bound to the HAESA ectodomain.	FIG
67	70	IDA	protein	no detectable binding). (E) Structural superposition of the active IDA (in bonds representation, in gray) and IDL1 peptide (in yellow) hormones bound to the HAESA ectodomain.	FIG
110	122	IDL1 peptide	chemical	no detectable binding). (E) Structural superposition of the active IDA (in bonds representation, in gray) and IDL1 peptide (in yellow) hormones bound to the HAESA ectodomain.	FIG
144	152	bound to	protein_state	no detectable binding). (E) Structural superposition of the active IDA (in bonds representation, in gray) and IDL1 peptide (in yellow) hormones bound to the HAESA ectodomain.	FIG
157	162	HAESA	protein	no detectable binding). (E) Structural superposition of the active IDA (in bonds representation, in gray) and IDL1 peptide (in yellow) hormones bound to the HAESA ectodomain.	FIG
163	173	ectodomain	structure_element	no detectable binding). (E) Structural superposition of the active IDA (in bonds representation, in gray) and IDL1 peptide (in yellow) hormones bound to the HAESA ectodomain.	FIG
0	26	Root mean square deviation	evidence	Root mean square deviation (r.m.s.d.) is 1.0 Å comparing 100 corresponding atoms.	FIG
28	36	r.m.s.d.	evidence	Root mean square deviation (r.m.s.d.) is 1.0 Å comparing 100 corresponding atoms.	FIG
4	19	receptor kinase	protein_type	The receptor kinase SERK1 acts as a HAESA co-receptor and promotes high-affinity IDA sensing.	FIG
20	25	SERK1	protein	The receptor kinase SERK1 acts as a HAESA co-receptor and promotes high-affinity IDA sensing.	FIG
36	53	HAESA co-receptor	protein_type	The receptor kinase SERK1 acts as a HAESA co-receptor and promotes high-affinity IDA sensing.	FIG
81	84	IDA	protein	The receptor kinase SERK1 acts as a HAESA co-receptor and promotes high-affinity IDA sensing.	FIG
4	31	Petal break-strength assays	experimental_method	(A) Petal break-strength assays measure the force (expressed in gram equivalents) required to remove the petals from the flower of serk mutant plants compared to haesa/hsl2 mutant and Col-0 wild-type flowers.	FIG
131	135	serk	gene	(A) Petal break-strength assays measure the force (expressed in gram equivalents) required to remove the petals from the flower of serk mutant plants compared to haesa/hsl2 mutant and Col-0 wild-type flowers.	FIG
136	142	mutant	protein_state	(A) Petal break-strength assays measure the force (expressed in gram equivalents) required to remove the petals from the flower of serk mutant plants compared to haesa/hsl2 mutant and Col-0 wild-type flowers.	FIG
143	149	plants	taxonomy_domain	(A) Petal break-strength assays measure the force (expressed in gram equivalents) required to remove the petals from the flower of serk mutant plants compared to haesa/hsl2 mutant and Col-0 wild-type flowers.	FIG
162	167	haesa	gene	(A) Petal break-strength assays measure the force (expressed in gram equivalents) required to remove the petals from the flower of serk mutant plants compared to haesa/hsl2 mutant and Col-0 wild-type flowers.	FIG
168	172	hsl2	gene	(A) Petal break-strength assays measure the force (expressed in gram equivalents) required to remove the petals from the flower of serk mutant plants compared to haesa/hsl2 mutant and Col-0 wild-type flowers.	FIG
173	179	mutant	protein_state	(A) Petal break-strength assays measure the force (expressed in gram equivalents) required to remove the petals from the flower of serk mutant plants compared to haesa/hsl2 mutant and Col-0 wild-type flowers.	FIG
190	199	wild-type	protein_state	(A) Petal break-strength assays measure the force (expressed in gram equivalents) required to remove the petals from the flower of serk mutant plants compared to haesa/hsl2 mutant and Col-0 wild-type flowers.	FIG
104	109	haesa	gene	Petal break-strength was found significantly increased in almost all positions (indicated with a *) for haesa/hsl2 and serk1-1 mutant plants with respect to the Col-0 control.	FIG
110	114	hsl2	gene	Petal break-strength was found significantly increased in almost all positions (indicated with a *) for haesa/hsl2 and serk1-1 mutant plants with respect to the Col-0 control.	FIG
119	126	serk1-1	gene	Petal break-strength was found significantly increased in almost all positions (indicated with a *) for haesa/hsl2 and serk1-1 mutant plants with respect to the Col-0 control.	FIG
127	133	mutant	protein_state	Petal break-strength was found significantly increased in almost all positions (indicated with a *) for haesa/hsl2 and serk1-1 mutant plants with respect to the Col-0 control.	FIG
134	140	plants	taxonomy_domain	Petal break-strength was found significantly increased in almost all positions (indicated with a *) for haesa/hsl2 and serk1-1 mutant plants with respect to the Col-0 control.	FIG
4	44	Analytical size-exclusion chromatography	experimental_method	(B) Analytical size-exclusion chromatography.	FIG
4	9	HAESA	protein	The HAESA LRR domain elutes as a monomer (black dotted line), as does the isolated SERK1 ectodomain (blue dotted line).	FIG
10	20	LRR domain	structure_element	The HAESA LRR domain elutes as a monomer (black dotted line), as does the isolated SERK1 ectodomain (blue dotted line).	FIG
33	40	monomer	oligomeric_state	The HAESA LRR domain elutes as a monomer (black dotted line), as does the isolated SERK1 ectodomain (blue dotted line).	FIG
83	88	SERK1	protein	The HAESA LRR domain elutes as a monomer (black dotted line), as does the isolated SERK1 ectodomain (blue dotted line).	FIG
89	99	ectodomain	structure_element	The HAESA LRR domain elutes as a monomer (black dotted line), as does the isolated SERK1 ectodomain (blue dotted line).	FIG
2	21	HAESA – IDA – SERK1	complex_assembly	A HAESA – IDA – SERK1 complex elutes as an apparent heterodimer (red line), while a mixture of HAESA and SERK1 yields two isolated peaks that correspond to monomeric HAESA and SERK1, respectively (black line).	FIG
52	63	heterodimer	oligomeric_state	A HAESA – IDA – SERK1 complex elutes as an apparent heterodimer (red line), while a mixture of HAESA and SERK1 yields two isolated peaks that correspond to monomeric HAESA and SERK1, respectively (black line).	FIG
95	100	HAESA	protein	A HAESA – IDA – SERK1 complex elutes as an apparent heterodimer (red line), while a mixture of HAESA and SERK1 yields two isolated peaks that correspond to monomeric HAESA and SERK1, respectively (black line).	FIG
105	110	SERK1	protein	A HAESA – IDA – SERK1 complex elutes as an apparent heterodimer (red line), while a mixture of HAESA and SERK1 yields two isolated peaks that correspond to monomeric HAESA and SERK1, respectively (black line).	FIG
156	165	monomeric	oligomeric_state	A HAESA – IDA – SERK1 complex elutes as an apparent heterodimer (red line), while a mixture of HAESA and SERK1 yields two isolated peaks that correspond to monomeric HAESA and SERK1, respectively (black line).	FIG
166	171	HAESA	protein	A HAESA – IDA – SERK1 complex elutes as an apparent heterodimer (red line), while a mixture of HAESA and SERK1 yields two isolated peaks that correspond to monomeric HAESA and SERK1, respectively (black line).	FIG
176	181	SERK1	protein	A HAESA – IDA – SERK1 complex elutes as an apparent heterodimer (red line), while a mixture of HAESA and SERK1 yields two isolated peaks that correspond to monomeric HAESA and SERK1, respectively (black line).	FIG
113	126	Thyroglobulin	protein	Void (V0) volume and total volume (Vt) are shown, together with elution volumes for molecular mass standards (A, Thyroglobulin, 669,000 Da; B, Ferritin, 440,00 Da, C, Aldolase, 158,000 Da; D, Conalbumin, 75,000 Da; E, Ovalbumin, 44,000 Da; F, Carbonic anhydrase, 29,000 Da).	FIG
143	151	Ferritin	protein	Void (V0) volume and total volume (Vt) are shown, together with elution volumes for molecular mass standards (A, Thyroglobulin, 669,000 Da; B, Ferritin, 440,00 Da, C, Aldolase, 158,000 Da; D, Conalbumin, 75,000 Da; E, Ovalbumin, 44,000 Da; F, Carbonic anhydrase, 29,000 Da).	FIG
167	175	Aldolase	protein	Void (V0) volume and total volume (Vt) are shown, together with elution volumes for molecular mass standards (A, Thyroglobulin, 669,000 Da; B, Ferritin, 440,00 Da, C, Aldolase, 158,000 Da; D, Conalbumin, 75,000 Da; E, Ovalbumin, 44,000 Da; F, Carbonic anhydrase, 29,000 Da).	FIG
192	202	Conalbumin	protein	Void (V0) volume and total volume (Vt) are shown, together with elution volumes for molecular mass standards (A, Thyroglobulin, 669,000 Da; B, Ferritin, 440,00 Da, C, Aldolase, 158,000 Da; D, Conalbumin, 75,000 Da; E, Ovalbumin, 44,000 Da; F, Carbonic anhydrase, 29,000 Da).	FIG
218	227	Ovalbumin	protein	Void (V0) volume and total volume (Vt) are shown, together with elution volumes for molecular mass standards (A, Thyroglobulin, 669,000 Da; B, Ferritin, 440,00 Da, C, Aldolase, 158,000 Da; D, Conalbumin, 75,000 Da; E, Ovalbumin, 44,000 Da; F, Carbonic anhydrase, 29,000 Da).	FIG
243	261	Carbonic anhydrase	protein	Void (V0) volume and total volume (Vt) are shown, together with elution volumes for molecular mass standards (A, Thyroglobulin, 669,000 Da; B, Ferritin, 440,00 Da, C, Aldolase, 158,000 Da; D, Conalbumin, 75,000 Da; E, Ovalbumin, 44,000 Da; F, Carbonic anhydrase, 29,000 Da).	FIG
113	126	Thyroglobulin	protein	Void (V0) volume and total volume (Vt) are shown, together with elution volumes for molecular mass standards (A, Thyroglobulin, 669,000 Da; B, Ferritin, 440,00 Da, C, Aldolase, 158,000 Da; D, Conalbumin, 75,000 Da; E, Ovalbumin, 44,000 Da; F, Carbonic anhydrase, 29,000 Da).	FIG
143	151	Ferritin	protein	Void (V0) volume and total volume (Vt) are shown, together with elution volumes for molecular mass standards (A, Thyroglobulin, 669,000 Da; B, Ferritin, 440,00 Da, C, Aldolase, 158,000 Da; D, Conalbumin, 75,000 Da; E, Ovalbumin, 44,000 Da; F, Carbonic anhydrase, 29,000 Da).	FIG
167	175	Aldolase	protein	Void (V0) volume and total volume (Vt) are shown, together with elution volumes for molecular mass standards (A, Thyroglobulin, 669,000 Da; B, Ferritin, 440,00 Da, C, Aldolase, 158,000 Da; D, Conalbumin, 75,000 Da; E, Ovalbumin, 44,000 Da; F, Carbonic anhydrase, 29,000 Da).	FIG
192	202	Conalbumin	protein	Void (V0) volume and total volume (Vt) are shown, together with elution volumes for molecular mass standards (A, Thyroglobulin, 669,000 Da; B, Ferritin, 440,00 Da, C, Aldolase, 158,000 Da; D, Conalbumin, 75,000 Da; E, Ovalbumin, 44,000 Da; F, Carbonic anhydrase, 29,000 Da).	FIG
218	227	Ovalbumin	protein	Void (V0) volume and total volume (Vt) are shown, together with elution volumes for molecular mass standards (A, Thyroglobulin, 669,000 Da; B, Ferritin, 440,00 Da, C, Aldolase, 158,000 Da; D, Conalbumin, 75,000 Da; E, Ovalbumin, 44,000 Da; F, Carbonic anhydrase, 29,000 Da).	FIG
243	261	Carbonic anhydrase	protein	Void (V0) volume and total volume (Vt) are shown, together with elution volumes for molecular mass standards (A, Thyroglobulin, 669,000 Da; B, Ferritin, 440,00 Da, C, Aldolase, 158,000 Da; D, Conalbumin, 75,000 Da; E, Ovalbumin, 44,000 Da; F, Carbonic anhydrase, 29,000 Da).	FIG
2	10	SDS PAGE	experimental_method	A SDS PAGE of the peak fractions is shown alongside.	FIG
2	10	SDS PAGE	experimental_method	A SDS PAGE of the peak fractions is shown alongside.	FIG
9	14	HAESA	protein	Purified HAESA and SERK1 are ~75 and ~28 kDa, respectively. (C) Isothermal titration calorimetry of wild-type and Hyp64→Pro IDA versus the HAESA and SERK1 ectodomains.	FIG
19	24	SERK1	protein	Purified HAESA and SERK1 are ~75 and ~28 kDa, respectively. (C) Isothermal titration calorimetry of wild-type and Hyp64→Pro IDA versus the HAESA and SERK1 ectodomains.	FIG
64	96	Isothermal titration calorimetry	experimental_method	Purified HAESA and SERK1 are ~75 and ~28 kDa, respectively. (C) Isothermal titration calorimetry of wild-type and Hyp64→Pro IDA versus the HAESA and SERK1 ectodomains.	FIG
100	109	wild-type	protein_state	Purified HAESA and SERK1 are ~75 and ~28 kDa, respectively. (C) Isothermal titration calorimetry of wild-type and Hyp64→Pro IDA versus the HAESA and SERK1 ectodomains.	FIG
114	123	Hyp64→Pro	ptm	Purified HAESA and SERK1 are ~75 and ~28 kDa, respectively. (C) Isothermal titration calorimetry of wild-type and Hyp64→Pro IDA versus the HAESA and SERK1 ectodomains.	FIG
114	119	Hyp64	ptm	Purified HAESA and SERK1 are ~75 and ~28 kDa, respectively. (C) Isothermal titration calorimetry of wild-type and Hyp64→Pro IDA versus the HAESA and SERK1 ectodomains.	FIG
124	127	IDA	protein	Purified HAESA and SERK1 are ~75 and ~28 kDa, respectively. (C) Isothermal titration calorimetry of wild-type and Hyp64→Pro IDA versus the HAESA and SERK1 ectodomains.	FIG
139	144	HAESA	protein	Purified HAESA and SERK1 are ~75 and ~28 kDa, respectively. (C) Isothermal titration calorimetry of wild-type and Hyp64→Pro IDA versus the HAESA and SERK1 ectodomains.	FIG
149	154	SERK1	protein	Purified HAESA and SERK1 are ~75 and ~28 kDa, respectively. (C) Isothermal titration calorimetry of wild-type and Hyp64→Pro IDA versus the HAESA and SERK1 ectodomains.	FIG
155	166	ectodomains	structure_element	Purified HAESA and SERK1 are ~75 and ~28 kDa, respectively. (C) Isothermal titration calorimetry of wild-type and Hyp64→Pro IDA versus the HAESA and SERK1 ectodomains.	FIG
4	13	titration	experimental_method	The titration of IDA wild-type versus the isolated HAESA ectodomain from Figure 1B is shown for comparison (red line; n.d.	FIG
17	20	IDA	protein	The titration of IDA wild-type versus the isolated HAESA ectodomain from Figure 1B is shown for comparison (red line; n.d.	FIG
21	30	wild-type	protein_state	The titration of IDA wild-type versus the isolated HAESA ectodomain from Figure 1B is shown for comparison (red line; n.d.	FIG
51	56	HAESA	protein	The titration of IDA wild-type versus the isolated HAESA ectodomain from Figure 1B is shown for comparison (red line; n.d.	FIG
57	67	ectodomain	structure_element	The titration of IDA wild-type versus the isolated HAESA ectodomain from Figure 1B is shown for comparison (red line; n.d.	FIG
27	67	Analytical size-exclusion chromatography	experimental_method	no detectable binding) (D) Analytical size-exclusion chromatography in the presence of the IDA Hyp64→Pro mutant peptide reveals no complex formation between HAESA and SERK1 ectodomains.	FIG
75	86	presence of	protein_state	no detectable binding) (D) Analytical size-exclusion chromatography in the presence of the IDA Hyp64→Pro mutant peptide reveals no complex formation between HAESA and SERK1 ectodomains.	FIG
91	94	IDA	protein	no detectable binding) (D) Analytical size-exclusion chromatography in the presence of the IDA Hyp64→Pro mutant peptide reveals no complex formation between HAESA and SERK1 ectodomains.	FIG
95	104	Hyp64→Pro	ptm	no detectable binding) (D) Analytical size-exclusion chromatography in the presence of the IDA Hyp64→Pro mutant peptide reveals no complex formation between HAESA and SERK1 ectodomains.	FIG
95	100	Hyp64	ptm	no detectable binding) (D) Analytical size-exclusion chromatography in the presence of the IDA Hyp64→Pro mutant peptide reveals no complex formation between HAESA and SERK1 ectodomains.	FIG
105	111	mutant	protein_state	no detectable binding) (D) Analytical size-exclusion chromatography in the presence of the IDA Hyp64→Pro mutant peptide reveals no complex formation between HAESA and SERK1 ectodomains.	FIG
112	119	peptide	chemical	no detectable binding) (D) Analytical size-exclusion chromatography in the presence of the IDA Hyp64→Pro mutant peptide reveals no complex formation between HAESA and SERK1 ectodomains.	FIG
157	162	HAESA	protein	no detectable binding) (D) Analytical size-exclusion chromatography in the presence of the IDA Hyp64→Pro mutant peptide reveals no complex formation between HAESA and SERK1 ectodomains.	FIG
167	172	SERK1	protein	no detectable binding) (D) Analytical size-exclusion chromatography in the presence of the IDA Hyp64→Pro mutant peptide reveals no complex formation between HAESA and SERK1 ectodomains.	FIG
173	184	ectodomains	structure_element	no detectable binding) (D) Analytical size-exclusion chromatography in the presence of the IDA Hyp64→Pro mutant peptide reveals no complex formation between HAESA and SERK1 ectodomains.	FIG
4	26	In vitro kinase assays	experimental_method	(E) In vitro kinase assays of the HAESA and SERK1 kinase domains.	FIG
34	39	HAESA	protein	(E) In vitro kinase assays of the HAESA and SERK1 kinase domains.	FIG
44	49	SERK1	protein	(E) In vitro kinase assays of the HAESA and SERK1 kinase domains.	FIG
50	64	kinase domains	structure_element	(E) In vitro kinase assays of the HAESA and SERK1 kinase domains.	FIG
0	9	Wild-type	protein_state	Wild-type HAESA and SERK1 kinase domains (KDs) exhibit auto-phosphorylation activities (lanes 1 + 3).	FIG
10	15	HAESA	protein	Wild-type HAESA and SERK1 kinase domains (KDs) exhibit auto-phosphorylation activities (lanes 1 + 3).	FIG
20	25	SERK1	protein	Wild-type HAESA and SERK1 kinase domains (KDs) exhibit auto-phosphorylation activities (lanes 1 + 3).	FIG
26	40	kinase domains	structure_element	Wild-type HAESA and SERK1 kinase domains (KDs) exhibit auto-phosphorylation activities (lanes 1 + 3).	FIG
42	45	KDs	structure_element	Wild-type HAESA and SERK1 kinase domains (KDs) exhibit auto-phosphorylation activities (lanes 1 + 3).	FIG
0	6	Mutant	protein_state	Mutant (m) versions, which carry point mutations in their active sites (Asp837HAESA→Asn, Asp447SERK1→Asn) possess no autophosphorylation activity (lanes 2+4).	FIG
33	48	point mutations	experimental_method	Mutant (m) versions, which carry point mutations in their active sites (Asp837HAESA→Asn, Asp447SERK1→Asn) possess no autophosphorylation activity (lanes 2+4).	FIG
58	70	active sites	site	Mutant (m) versions, which carry point mutations in their active sites (Asp837HAESA→Asn, Asp447SERK1→Asn) possess no autophosphorylation activity (lanes 2+4).	FIG
72	87	Asp837HAESA→Asn	mutant	Mutant (m) versions, which carry point mutations in their active sites (Asp837HAESA→Asn, Asp447SERK1→Asn) possess no autophosphorylation activity (lanes 2+4).	FIG
89	104	Asp447SERK1→Asn	mutant	Mutant (m) versions, which carry point mutations in their active sites (Asp837HAESA→Asn, Asp447SERK1→Asn) possess no autophosphorylation activity (lanes 2+4).	FIG
39	45	active	protein_state	Transphosphorylation activity from the active kinase to the mutated form can be observed in both directions (lanes 5+6).	FIG
60	67	mutated	protein_state	Transphosphorylation activity from the active kinase to the mutated form can be observed in both directions (lanes 5+6).	FIG
3	11	purified	experimental_method	We purified the HAESA ectodomain (residues 20–620) from baculovirus-infected insect cells (Figure 1—figure supplement 1A, see Materials and methods) and quantified the interaction of the ~75 kDa glycoprotein with synthetic IDA peptides using isothermal titration calorimetry (ITC).	RESULTS
16	21	HAESA	protein	We purified the HAESA ectodomain (residues 20–620) from baculovirus-infected insect cells (Figure 1—figure supplement 1A, see Materials and methods) and quantified the interaction of the ~75 kDa glycoprotein with synthetic IDA peptides using isothermal titration calorimetry (ITC).	RESULTS
22	32	ectodomain	structure_element	We purified the HAESA ectodomain (residues 20–620) from baculovirus-infected insect cells (Figure 1—figure supplement 1A, see Materials and methods) and quantified the interaction of the ~75 kDa glycoprotein with synthetic IDA peptides using isothermal titration calorimetry (ITC).	RESULTS
43	49	20–620	residue_range	We purified the HAESA ectodomain (residues 20–620) from baculovirus-infected insect cells (Figure 1—figure supplement 1A, see Materials and methods) and quantified the interaction of the ~75 kDa glycoprotein with synthetic IDA peptides using isothermal titration calorimetry (ITC).	RESULTS
56	89	baculovirus-infected insect cells	experimental_method	We purified the HAESA ectodomain (residues 20–620) from baculovirus-infected insect cells (Figure 1—figure supplement 1A, see Materials and methods) and quantified the interaction of the ~75 kDa glycoprotein with synthetic IDA peptides using isothermal titration calorimetry (ITC).	RESULTS
195	207	glycoprotein	protein_type	We purified the HAESA ectodomain (residues 20–620) from baculovirus-infected insect cells (Figure 1—figure supplement 1A, see Materials and methods) and quantified the interaction of the ~75 kDa glycoprotein with synthetic IDA peptides using isothermal titration calorimetry (ITC).	RESULTS
213	222	synthetic	protein_state	We purified the HAESA ectodomain (residues 20–620) from baculovirus-infected insect cells (Figure 1—figure supplement 1A, see Materials and methods) and quantified the interaction of the ~75 kDa glycoprotein with synthetic IDA peptides using isothermal titration calorimetry (ITC).	RESULTS
223	235	IDA peptides	chemical	We purified the HAESA ectodomain (residues 20–620) from baculovirus-infected insect cells (Figure 1—figure supplement 1A, see Materials and methods) and quantified the interaction of the ~75 kDa glycoprotein with synthetic IDA peptides using isothermal titration calorimetry (ITC).	RESULTS
242	274	isothermal titration calorimetry	experimental_method	We purified the HAESA ectodomain (residues 20–620) from baculovirus-infected insect cells (Figure 1—figure supplement 1A, see Materials and methods) and quantified the interaction of the ~75 kDa glycoprotein with synthetic IDA peptides using isothermal titration calorimetry (ITC).	RESULTS
276	279	ITC	experimental_method	We purified the HAESA ectodomain (residues 20–620) from baculovirus-infected insect cells (Figure 1—figure supplement 1A, see Materials and methods) and quantified the interaction of the ~75 kDa glycoprotein with synthetic IDA peptides using isothermal titration calorimetry (ITC).	RESULTS
2	14	Hyp-modified	protein_state	A Hyp-modified dodecamer comprising the highly conserved PIP motif in IDA (Figure 1A) interacts with HAESA with 1:1 stoichiometry (N) and with a dissociation constant (Kd) of ~20 μM (Figure 1B).	RESULTS
15	24	dodecamer	structure_element	A Hyp-modified dodecamer comprising the highly conserved PIP motif in IDA (Figure 1A) interacts with HAESA with 1:1 stoichiometry (N) and with a dissociation constant (Kd) of ~20 μM (Figure 1B).	RESULTS
40	56	highly conserved	protein_state	A Hyp-modified dodecamer comprising the highly conserved PIP motif in IDA (Figure 1A) interacts with HAESA with 1:1 stoichiometry (N) and with a dissociation constant (Kd) of ~20 μM (Figure 1B).	RESULTS
57	66	PIP motif	structure_element	A Hyp-modified dodecamer comprising the highly conserved PIP motif in IDA (Figure 1A) interacts with HAESA with 1:1 stoichiometry (N) and with a dissociation constant (Kd) of ~20 μM (Figure 1B).	RESULTS
70	73	IDA	protein	A Hyp-modified dodecamer comprising the highly conserved PIP motif in IDA (Figure 1A) interacts with HAESA with 1:1 stoichiometry (N) and with a dissociation constant (Kd) of ~20 μM (Figure 1B).	RESULTS
101	106	HAESA	protein	A Hyp-modified dodecamer comprising the highly conserved PIP motif in IDA (Figure 1A) interacts with HAESA with 1:1 stoichiometry (N) and with a dissociation constant (Kd) of ~20 μM (Figure 1B).	RESULTS
145	166	dissociation constant	evidence	A Hyp-modified dodecamer comprising the highly conserved PIP motif in IDA (Figure 1A) interacts with HAESA with 1:1 stoichiometry (N) and with a dissociation constant (Kd) of ~20 μM (Figure 1B).	RESULTS
168	170	Kd	evidence	A Hyp-modified dodecamer comprising the highly conserved PIP motif in IDA (Figure 1A) interacts with HAESA with 1:1 stoichiometry (N) and with a dissociation constant (Kd) of ~20 μM (Figure 1B).	RESULTS
19	37	crystal structures	evidence	We next determined crystal structures of the apo HAESA ectodomain and of a HAESA-IDA complex, at 1.74 and 1.86 Å resolution, respectively (Figure 1C; Figure 1—figure supplement 1B–D; Tables 1,2).	RESULTS
45	48	apo	protein_state	We next determined crystal structures of the apo HAESA ectodomain and of a HAESA-IDA complex, at 1.74 and 1.86 Å resolution, respectively (Figure 1C; Figure 1—figure supplement 1B–D; Tables 1,2).	RESULTS
49	54	HAESA	protein	We next determined crystal structures of the apo HAESA ectodomain and of a HAESA-IDA complex, at 1.74 and 1.86 Å resolution, respectively (Figure 1C; Figure 1—figure supplement 1B–D; Tables 1,2).	RESULTS
55	65	ectodomain	structure_element	We next determined crystal structures of the apo HAESA ectodomain and of a HAESA-IDA complex, at 1.74 and 1.86 Å resolution, respectively (Figure 1C; Figure 1—figure supplement 1B–D; Tables 1,2).	RESULTS
75	84	HAESA-IDA	complex_assembly	We next determined crystal structures of the apo HAESA ectodomain and of a HAESA-IDA complex, at 1.74 and 1.86 Å resolution, respectively (Figure 1C; Figure 1—figure supplement 1B–D; Tables 1,2).	RESULTS
0	3	IDA	protein	IDA binds in a completely extended conformation along the inner surface of the HAESA ectodomain, covering LRRs 2–14 (Figure 1C,D, Figure 1—figure supplement 2).	RESULTS
15	47	completely extended conformation	protein_state	IDA binds in a completely extended conformation along the inner surface of the HAESA ectodomain, covering LRRs 2–14 (Figure 1C,D, Figure 1—figure supplement 2).	RESULTS
79	84	HAESA	protein	IDA binds in a completely extended conformation along the inner surface of the HAESA ectodomain, covering LRRs 2–14 (Figure 1C,D, Figure 1—figure supplement 2).	RESULTS
85	95	ectodomain	structure_element	IDA binds in a completely extended conformation along the inner surface of the HAESA ectodomain, covering LRRs 2–14 (Figure 1C,D, Figure 1—figure supplement 2).	RESULTS
106	115	LRRs 2–14	structure_element	IDA binds in a completely extended conformation along the inner surface of the HAESA ectodomain, covering LRRs 2–14 (Figure 1C,D, Figure 1—figure supplement 2).	RESULTS
12	17	Hyp64	ptm	The central Hyp64IDA is buried in a specific pocket formed by HAESA LRRs 8–10, with its hydroxyl group establishing hydrogen bonds with the strictly conserved Glu266HAESA and with a water molecule, which in turn is coordinated by the main chain oxygens of Phe289HAESA and Ser311HAESA (Figure 1E; Figure 1—figure supplement 3).	RESULTS
17	20	IDA	protein	The central Hyp64IDA is buried in a specific pocket formed by HAESA LRRs 8–10, with its hydroxyl group establishing hydrogen bonds with the strictly conserved Glu266HAESA and with a water molecule, which in turn is coordinated by the main chain oxygens of Phe289HAESA and Ser311HAESA (Figure 1E; Figure 1—figure supplement 3).	RESULTS
45	51	pocket	site	The central Hyp64IDA is buried in a specific pocket formed by HAESA LRRs 8–10, with its hydroxyl group establishing hydrogen bonds with the strictly conserved Glu266HAESA and with a water molecule, which in turn is coordinated by the main chain oxygens of Phe289HAESA and Ser311HAESA (Figure 1E; Figure 1—figure supplement 3).	RESULTS
62	67	HAESA	protein	The central Hyp64IDA is buried in a specific pocket formed by HAESA LRRs 8–10, with its hydroxyl group establishing hydrogen bonds with the strictly conserved Glu266HAESA and with a water molecule, which in turn is coordinated by the main chain oxygens of Phe289HAESA and Ser311HAESA (Figure 1E; Figure 1—figure supplement 3).	RESULTS
68	77	LRRs 8–10	structure_element	The central Hyp64IDA is buried in a specific pocket formed by HAESA LRRs 8–10, with its hydroxyl group establishing hydrogen bonds with the strictly conserved Glu266HAESA and with a water molecule, which in turn is coordinated by the main chain oxygens of Phe289HAESA and Ser311HAESA (Figure 1E; Figure 1—figure supplement 3).	RESULTS
116	130	hydrogen bonds	bond_interaction	The central Hyp64IDA is buried in a specific pocket formed by HAESA LRRs 8–10, with its hydroxyl group establishing hydrogen bonds with the strictly conserved Glu266HAESA and with a water molecule, which in turn is coordinated by the main chain oxygens of Phe289HAESA and Ser311HAESA (Figure 1E; Figure 1—figure supplement 3).	RESULTS
140	158	strictly conserved	protein_state	The central Hyp64IDA is buried in a specific pocket formed by HAESA LRRs 8–10, with its hydroxyl group establishing hydrogen bonds with the strictly conserved Glu266HAESA and with a water molecule, which in turn is coordinated by the main chain oxygens of Phe289HAESA and Ser311HAESA (Figure 1E; Figure 1—figure supplement 3).	RESULTS
159	165	Glu266	residue_name_number	The central Hyp64IDA is buried in a specific pocket formed by HAESA LRRs 8–10, with its hydroxyl group establishing hydrogen bonds with the strictly conserved Glu266HAESA and with a water molecule, which in turn is coordinated by the main chain oxygens of Phe289HAESA and Ser311HAESA (Figure 1E; Figure 1—figure supplement 3).	RESULTS
165	170	HAESA	protein	The central Hyp64IDA is buried in a specific pocket formed by HAESA LRRs 8–10, with its hydroxyl group establishing hydrogen bonds with the strictly conserved Glu266HAESA and with a water molecule, which in turn is coordinated by the main chain oxygens of Phe289HAESA and Ser311HAESA (Figure 1E; Figure 1—figure supplement 3).	RESULTS
182	187	water	chemical	The central Hyp64IDA is buried in a specific pocket formed by HAESA LRRs 8–10, with its hydroxyl group establishing hydrogen bonds with the strictly conserved Glu266HAESA and with a water molecule, which in turn is coordinated by the main chain oxygens of Phe289HAESA and Ser311HAESA (Figure 1E; Figure 1—figure supplement 3).	RESULTS
256	262	Phe289	residue_name_number	The central Hyp64IDA is buried in a specific pocket formed by HAESA LRRs 8–10, with its hydroxyl group establishing hydrogen bonds with the strictly conserved Glu266HAESA and with a water molecule, which in turn is coordinated by the main chain oxygens of Phe289HAESA and Ser311HAESA (Figure 1E; Figure 1—figure supplement 3).	RESULTS
262	267	HAESA	protein	The central Hyp64IDA is buried in a specific pocket formed by HAESA LRRs 8–10, with its hydroxyl group establishing hydrogen bonds with the strictly conserved Glu266HAESA and with a water molecule, which in turn is coordinated by the main chain oxygens of Phe289HAESA and Ser311HAESA (Figure 1E; Figure 1—figure supplement 3).	RESULTS
272	278	Ser311	residue_name_number	The central Hyp64IDA is buried in a specific pocket formed by HAESA LRRs 8–10, with its hydroxyl group establishing hydrogen bonds with the strictly conserved Glu266HAESA and with a water molecule, which in turn is coordinated by the main chain oxygens of Phe289HAESA and Ser311HAESA (Figure 1E; Figure 1—figure supplement 3).	RESULTS
278	283	HAESA	protein	The central Hyp64IDA is buried in a specific pocket formed by HAESA LRRs 8–10, with its hydroxyl group establishing hydrogen bonds with the strictly conserved Glu266HAESA and with a water molecule, which in turn is coordinated by the main chain oxygens of Phe289HAESA and Ser311HAESA (Figure 1E; Figure 1—figure supplement 3).	RESULTS
27	37	Hyp pocket	site	The restricted size of the Hyp pocket suggests that IDA does not require arabinosylation of Hyp64IDA for activity in vivo, a modification that has been reported for Hyp residues in plant CLE peptide hormones.	RESULTS
52	55	IDA	protein	The restricted size of the Hyp pocket suggests that IDA does not require arabinosylation of Hyp64IDA for activity in vivo, a modification that has been reported for Hyp residues in plant CLE peptide hormones.	RESULTS
73	88	arabinosylation	ptm	The restricted size of the Hyp pocket suggests that IDA does not require arabinosylation of Hyp64IDA for activity in vivo, a modification that has been reported for Hyp residues in plant CLE peptide hormones.	RESULTS
92	97	Hyp64	ptm	The restricted size of the Hyp pocket suggests that IDA does not require arabinosylation of Hyp64IDA for activity in vivo, a modification that has been reported for Hyp residues in plant CLE peptide hormones.	RESULTS
97	100	IDA	protein	The restricted size of the Hyp pocket suggests that IDA does not require arabinosylation of Hyp64IDA for activity in vivo, a modification that has been reported for Hyp residues in plant CLE peptide hormones.	RESULTS
165	168	Hyp	residue_name	The restricted size of the Hyp pocket suggests that IDA does not require arabinosylation of Hyp64IDA for activity in vivo, a modification that has been reported for Hyp residues in plant CLE peptide hormones.	RESULTS
181	186	plant	taxonomy_domain	The restricted size of the Hyp pocket suggests that IDA does not require arabinosylation of Hyp64IDA for activity in vivo, a modification that has been reported for Hyp residues in plant CLE peptide hormones.	RESULTS
187	207	CLE peptide hormones	protein_type	The restricted size of the Hyp pocket suggests that IDA does not require arabinosylation of Hyp64IDA for activity in vivo, a modification that has been reported for Hyp residues in plant CLE peptide hormones.	RESULTS
15	32	Arg-His-Asn motif	structure_element	The C-terminal Arg-His-Asn motif in IDA maps to a cavity formed by HAESA LRRs 11–14 (Figure 1D,F).	RESULTS
36	39	IDA	protein	The C-terminal Arg-His-Asn motif in IDA maps to a cavity formed by HAESA LRRs 11–14 (Figure 1D,F).	RESULTS
50	56	cavity	site	The C-terminal Arg-His-Asn motif in IDA maps to a cavity formed by HAESA LRRs 11–14 (Figure 1D,F).	RESULTS
67	72	HAESA	protein	The C-terminal Arg-His-Asn motif in IDA maps to a cavity formed by HAESA LRRs 11–14 (Figure 1D,F).	RESULTS
73	83	LRRs 11–14	structure_element	The C-terminal Arg-His-Asn motif in IDA maps to a cavity formed by HAESA LRRs 11–14 (Figure 1D,F).	RESULTS
18	23	Asn69	residue_name_number	The COO- group of Asn69IDA is in direct contact with Arg407HAESA and Arg409HAESA and HAESA cannot bind a C-terminally extended IDA-SFVN peptide (Figures 1D,F, 2D).	RESULTS
23	26	IDA	protein	The COO- group of Asn69IDA is in direct contact with Arg407HAESA and Arg409HAESA and HAESA cannot bind a C-terminally extended IDA-SFVN peptide (Figures 1D,F, 2D).	RESULTS
53	59	Arg407	residue_name_number	The COO- group of Asn69IDA is in direct contact with Arg407HAESA and Arg409HAESA and HAESA cannot bind a C-terminally extended IDA-SFVN peptide (Figures 1D,F, 2D).	RESULTS
59	64	HAESA	protein	The COO- group of Asn69IDA is in direct contact with Arg407HAESA and Arg409HAESA and HAESA cannot bind a C-terminally extended IDA-SFVN peptide (Figures 1D,F, 2D).	RESULTS
69	75	Arg409	residue_name_number	The COO- group of Asn69IDA is in direct contact with Arg407HAESA and Arg409HAESA and HAESA cannot bind a C-terminally extended IDA-SFVN peptide (Figures 1D,F, 2D).	RESULTS
75	80	HAESA	protein	The COO- group of Asn69IDA is in direct contact with Arg407HAESA and Arg409HAESA and HAESA cannot bind a C-terminally extended IDA-SFVN peptide (Figures 1D,F, 2D).	RESULTS
85	90	HAESA	protein	The COO- group of Asn69IDA is in direct contact with Arg407HAESA and Arg409HAESA and HAESA cannot bind a C-terminally extended IDA-SFVN peptide (Figures 1D,F, 2D).	RESULTS
105	126	C-terminally extended	protein_state	The COO- group of Asn69IDA is in direct contact with Arg407HAESA and Arg409HAESA and HAESA cannot bind a C-terminally extended IDA-SFVN peptide (Figures 1D,F, 2D).	RESULTS
127	135	IDA-SFVN	mutant	The COO- group of Asn69IDA is in direct contact with Arg407HAESA and Arg409HAESA and HAESA cannot bind a C-terminally extended IDA-SFVN peptide (Figures 1D,F, 2D).	RESULTS
23	32	conserved	protein_state	This suggests that the conserved Asn69IDA may constitute the very C-terminus of the mature IDA peptide in planta and that active IDA is generated by proteolytic processing from a longer pre-protein.	RESULTS
33	38	Asn69	residue_name_number	This suggests that the conserved Asn69IDA may constitute the very C-terminus of the mature IDA peptide in planta and that active IDA is generated by proteolytic processing from a longer pre-protein.	RESULTS
38	41	IDA	protein	This suggests that the conserved Asn69IDA may constitute the very C-terminus of the mature IDA peptide in planta and that active IDA is generated by proteolytic processing from a longer pre-protein.	RESULTS
84	90	mature	protein_state	This suggests that the conserved Asn69IDA may constitute the very C-terminus of the mature IDA peptide in planta and that active IDA is generated by proteolytic processing from a longer pre-protein.	RESULTS
91	102	IDA peptide	chemical	This suggests that the conserved Asn69IDA may constitute the very C-terminus of the mature IDA peptide in planta and that active IDA is generated by proteolytic processing from a longer pre-protein.	RESULTS
106	112	planta	taxonomy_domain	This suggests that the conserved Asn69IDA may constitute the very C-terminus of the mature IDA peptide in planta and that active IDA is generated by proteolytic processing from a longer pre-protein.	RESULTS
122	128	active	protein_state	This suggests that the conserved Asn69IDA may constitute the very C-terminus of the mature IDA peptide in planta and that active IDA is generated by proteolytic processing from a longer pre-protein.	RESULTS
129	132	IDA	protein	This suggests that the conserved Asn69IDA may constitute the very C-terminus of the mature IDA peptide in planta and that active IDA is generated by proteolytic processing from a longer pre-protein.	RESULTS
0	8	Mutation	experimental_method	Mutation of Arg417HSL2 (which corresponds to Arg409HAESA) causes a loss-of-function phenotype in HSL2, which indicates that the peptide binding pockets in different HAESA receptors have common structural and sequence features.	RESULTS
12	18	Arg417	residue_name_number	Mutation of Arg417HSL2 (which corresponds to Arg409HAESA) causes a loss-of-function phenotype in HSL2, which indicates that the peptide binding pockets in different HAESA receptors have common structural and sequence features.	RESULTS
18	22	HSL2	protein	Mutation of Arg417HSL2 (which corresponds to Arg409HAESA) causes a loss-of-function phenotype in HSL2, which indicates that the peptide binding pockets in different HAESA receptors have common structural and sequence features.	RESULTS
45	51	Arg409	residue_name_number	Mutation of Arg417HSL2 (which corresponds to Arg409HAESA) causes a loss-of-function phenotype in HSL2, which indicates that the peptide binding pockets in different HAESA receptors have common structural and sequence features.	RESULTS
51	56	HAESA	protein	Mutation of Arg417HSL2 (which corresponds to Arg409HAESA) causes a loss-of-function phenotype in HSL2, which indicates that the peptide binding pockets in different HAESA receptors have common structural and sequence features.	RESULTS
97	101	HSL2	protein	Mutation of Arg417HSL2 (which corresponds to Arg409HAESA) causes a loss-of-function phenotype in HSL2, which indicates that the peptide binding pockets in different HAESA receptors have common structural and sequence features.	RESULTS
128	151	peptide binding pockets	site	Mutation of Arg417HSL2 (which corresponds to Arg409HAESA) causes a loss-of-function phenotype in HSL2, which indicates that the peptide binding pockets in different HAESA receptors have common structural and sequence features.	RESULTS
165	180	HAESA receptors	protein_type	Mutation of Arg417HSL2 (which corresponds to Arg409HAESA) causes a loss-of-function phenotype in HSL2, which indicates that the peptide binding pockets in different HAESA receptors have common structural and sequence features.	RESULTS
74	93	IDA binding surface	site	Indeed, we find many of the residues contributing to the formation of the IDA binding surface in HAESA to be conserved in HSL2 and in other HAESA-type receptors in different plant species (Figure 1—figure supplement 3).	RESULTS
97	102	HAESA	protein	Indeed, we find many of the residues contributing to the formation of the IDA binding surface in HAESA to be conserved in HSL2 and in other HAESA-type receptors in different plant species (Figure 1—figure supplement 3).	RESULTS
109	118	conserved	protein_state	Indeed, we find many of the residues contributing to the formation of the IDA binding surface in HAESA to be conserved in HSL2 and in other HAESA-type receptors in different plant species (Figure 1—figure supplement 3).	RESULTS
122	126	HSL2	protein	Indeed, we find many of the residues contributing to the formation of the IDA binding surface in HAESA to be conserved in HSL2 and in other HAESA-type receptors in different plant species (Figure 1—figure supplement 3).	RESULTS
140	160	HAESA-type receptors	protein_type	Indeed, we find many of the residues contributing to the formation of the IDA binding surface in HAESA to be conserved in HSL2 and in other HAESA-type receptors in different plant species (Figure 1—figure supplement 3).	RESULTS
174	179	plant	taxonomy_domain	Indeed, we find many of the residues contributing to the formation of the IDA binding surface in HAESA to be conserved in HSL2 and in other HAESA-type receptors in different plant species (Figure 1—figure supplement 3).	RESULTS
13	27	Pro-rich motif	structure_element	A N-terminal Pro-rich motif in IDA makes contacts with LRRs 2–6 of the receptor (Figure 1D, Figure 1—figure supplement 2A–C).	RESULTS
31	34	IDA	protein	A N-terminal Pro-rich motif in IDA makes contacts with LRRs 2–6 of the receptor (Figure 1D, Figure 1—figure supplement 2A–C).	RESULTS
55	63	LRRs 2–6	structure_element	A N-terminal Pro-rich motif in IDA makes contacts with LRRs 2–6 of the receptor (Figure 1D, Figure 1—figure supplement 2A–C).	RESULTS
6	40	hydrophobic and polar interactions	bond_interaction	Other hydrophobic and polar interactions are mediated by Ser62IDA, Ser65IDA and by backbone atoms along the IDA peptide (Figure 1D, Figure 1—figure supplement 2A–C).	RESULTS
57	62	Ser62	residue_name_number	Other hydrophobic and polar interactions are mediated by Ser62IDA, Ser65IDA and by backbone atoms along the IDA peptide (Figure 1D, Figure 1—figure supplement 2A–C).	RESULTS
62	65	IDA	protein	Other hydrophobic and polar interactions are mediated by Ser62IDA, Ser65IDA and by backbone atoms along the IDA peptide (Figure 1D, Figure 1—figure supplement 2A–C).	RESULTS
67	72	Ser65	residue_name_number	Other hydrophobic and polar interactions are mediated by Ser62IDA, Ser65IDA and by backbone atoms along the IDA peptide (Figure 1D, Figure 1—figure supplement 2A–C).	RESULTS
72	75	IDA	protein	Other hydrophobic and polar interactions are mediated by Ser62IDA, Ser65IDA and by backbone atoms along the IDA peptide (Figure 1D, Figure 1—figure supplement 2A–C).	RESULTS
108	119	IDA peptide	chemical	Other hydrophobic and polar interactions are mediated by Ser62IDA, Ser65IDA and by backbone atoms along the IDA peptide (Figure 1D, Figure 1—figure supplement 2A–C).	RESULTS
0	5	HAESA	protein	HAESA specifically senses IDA-family dodecamer peptides	RESULTS
26	36	IDA-family	protein_type	HAESA specifically senses IDA-family dodecamer peptides	RESULTS
37	46	dodecamer	structure_element	HAESA specifically senses IDA-family dodecamer peptides	RESULTS
47	55	peptides	chemical	HAESA specifically senses IDA-family dodecamer peptides	RESULTS
29	34	HAESA	protein	We next investigated whether HAESA binds N-terminally extended versions of IDA.	RESULTS
41	62	N-terminally extended	protein_state	We next investigated whether HAESA binds N-terminally extended versions of IDA.	RESULTS
75	78	IDA	protein	We next investigated whether HAESA binds N-terminally extended versions of IDA.	RESULTS
14	23	structure	evidence	We obtained a structure of HAESA in complex with a PKGV-IDA peptide at 1.94 Å resolution (Table 2).	RESULTS
27	32	HAESA	protein	We obtained a structure of HAESA in complex with a PKGV-IDA peptide at 1.94 Å resolution (Table 2).	RESULTS
33	48	in complex with	protein_state	We obtained a structure of HAESA in complex with a PKGV-IDA peptide at 1.94 Å resolution (Table 2).	RESULTS
51	59	PKGV-IDA	mutant	We obtained a structure of HAESA in complex with a PKGV-IDA peptide at 1.94 Å resolution (Table 2).	RESULTS
60	67	peptide	chemical	We obtained a structure of HAESA in complex with a PKGV-IDA peptide at 1.94 Å resolution (Table 2).	RESULTS
8	17	structure	evidence	In this structure, no additional electron density accounts for the PKGV motif at the IDA N-terminus (Figure 2A,B).	RESULTS
33	49	electron density	evidence	In this structure, no additional electron density accounts for the PKGV motif at the IDA N-terminus (Figure 2A,B).	RESULTS
67	77	PKGV motif	structure_element	In this structure, no additional electron density accounts for the PKGV motif at the IDA N-terminus (Figure 2A,B).	RESULTS
85	88	IDA	protein	In this structure, no additional electron density accounts for the PKGV motif at the IDA N-terminus (Figure 2A,B).	RESULTS
14	22	PKGV-IDA	mutant	Consistently, PKGV-IDA and IDA have similar binding affinities in our ITC assays, further indicating that HAESA senses a dodecamer peptide comprising residues 58-69IDA (Figure 2D).	RESULTS
27	30	IDA	protein	Consistently, PKGV-IDA and IDA have similar binding affinities in our ITC assays, further indicating that HAESA senses a dodecamer peptide comprising residues 58-69IDA (Figure 2D).	RESULTS
44	62	binding affinities	evidence	Consistently, PKGV-IDA and IDA have similar binding affinities in our ITC assays, further indicating that HAESA senses a dodecamer peptide comprising residues 58-69IDA (Figure 2D).	RESULTS
70	80	ITC assays	experimental_method	Consistently, PKGV-IDA and IDA have similar binding affinities in our ITC assays, further indicating that HAESA senses a dodecamer peptide comprising residues 58-69IDA (Figure 2D).	RESULTS
106	111	HAESA	protein	Consistently, PKGV-IDA and IDA have similar binding affinities in our ITC assays, further indicating that HAESA senses a dodecamer peptide comprising residues 58-69IDA (Figure 2D).	RESULTS
121	130	dodecamer	structure_element	Consistently, PKGV-IDA and IDA have similar binding affinities in our ITC assays, further indicating that HAESA senses a dodecamer peptide comprising residues 58-69IDA (Figure 2D).	RESULTS
131	138	peptide	chemical	Consistently, PKGV-IDA and IDA have similar binding affinities in our ITC assays, further indicating that HAESA senses a dodecamer peptide comprising residues 58-69IDA (Figure 2D).	RESULTS
159	164	58-69	residue_range	Consistently, PKGV-IDA and IDA have similar binding affinities in our ITC assays, further indicating that HAESA senses a dodecamer peptide comprising residues 58-69IDA (Figure 2D).	RESULTS
164	167	IDA	protein	Consistently, PKGV-IDA and IDA have similar binding affinities in our ITC assays, further indicating that HAESA senses a dodecamer peptide comprising residues 58-69IDA (Figure 2D).	RESULTS
18	23	HAESA	protein	We next tested if HAESA binds other IDA peptide family members.	RESULTS
36	62	IDA peptide family members	chemical	We next tested if HAESA binds other IDA peptide family members.	RESULTS
0	4	IDL1	protein	IDL1, which can rescue IDA loss-of-function mutants when introduced in abscission zone cells, can also be sensed by HAESA, albeit with lower affinity (Figure 2D).	RESULTS
23	26	IDA	protein	IDL1, which can rescue IDA loss-of-function mutants when introduced in abscission zone cells, can also be sensed by HAESA, albeit with lower affinity (Figure 2D).	RESULTS
116	121	HAESA	protein	IDL1, which can rescue IDA loss-of-function mutants when introduced in abscission zone cells, can also be sensed by HAESA, albeit with lower affinity (Figure 2D).	RESULTS
141	149	affinity	evidence	IDL1, which can rescue IDA loss-of-function mutants when introduced in abscission zone cells, can also be sensed by HAESA, albeit with lower affinity (Figure 2D).	RESULTS
9	29	co-crystal structure	evidence	A 2.56 Å co-crystal structure with IDL1 reveals that different IDA family members use a common binding mode to interact with HAESA-type receptors (Figure 2A–C,E, Table 2).	RESULTS
35	39	IDL1	protein	A 2.56 Å co-crystal structure with IDL1 reveals that different IDA family members use a common binding mode to interact with HAESA-type receptors (Figure 2A–C,E, Table 2).	RESULTS
63	81	IDA family members	protein_type	A 2.56 Å co-crystal structure with IDL1 reveals that different IDA family members use a common binding mode to interact with HAESA-type receptors (Figure 2A–C,E, Table 2).	RESULTS
125	145	HAESA-type receptors	protein_type	A 2.56 Å co-crystal structure with IDL1 reveals that different IDA family members use a common binding mode to interact with HAESA-type receptors (Figure 2A–C,E, Table 2).	RESULTS
37	42	HAESA	protein	We do not detect interaction between HAESA and a synthetic peptide missing the C-terminal Asn69IDA (ΔN69), highlighting the importance of the polar interactions between the IDA carboxy-terminus and Arg407HAESA/Arg409HAESA (Figures 1F, 2D).	RESULTS
49	58	synthetic	protein_state	We do not detect interaction between HAESA and a synthetic peptide missing the C-terminal Asn69IDA (ΔN69), highlighting the importance of the polar interactions between the IDA carboxy-terminus and Arg407HAESA/Arg409HAESA (Figures 1F, 2D).	RESULTS
59	66	peptide	chemical	We do not detect interaction between HAESA and a synthetic peptide missing the C-terminal Asn69IDA (ΔN69), highlighting the importance of the polar interactions between the IDA carboxy-terminus and Arg407HAESA/Arg409HAESA (Figures 1F, 2D).	RESULTS
67	89	missing the C-terminal	protein_state	We do not detect interaction between HAESA and a synthetic peptide missing the C-terminal Asn69IDA (ΔN69), highlighting the importance of the polar interactions between the IDA carboxy-terminus and Arg407HAESA/Arg409HAESA (Figures 1F, 2D).	RESULTS
90	95	Asn69	residue_name_number	We do not detect interaction between HAESA and a synthetic peptide missing the C-terminal Asn69IDA (ΔN69), highlighting the importance of the polar interactions between the IDA carboxy-terminus and Arg407HAESA/Arg409HAESA (Figures 1F, 2D).	RESULTS
95	98	IDA	protein	We do not detect interaction between HAESA and a synthetic peptide missing the C-terminal Asn69IDA (ΔN69), highlighting the importance of the polar interactions between the IDA carboxy-terminus and Arg407HAESA/Arg409HAESA (Figures 1F, 2D).	RESULTS
100	104	ΔN69	mutant	We do not detect interaction between HAESA and a synthetic peptide missing the C-terminal Asn69IDA (ΔN69), highlighting the importance of the polar interactions between the IDA carboxy-terminus and Arg407HAESA/Arg409HAESA (Figures 1F, 2D).	RESULTS
142	160	polar interactions	bond_interaction	We do not detect interaction between HAESA and a synthetic peptide missing the C-terminal Asn69IDA (ΔN69), highlighting the importance of the polar interactions between the IDA carboxy-terminus and Arg407HAESA/Arg409HAESA (Figures 1F, 2D).	RESULTS
173	176	IDA	protein	We do not detect interaction between HAESA and a synthetic peptide missing the C-terminal Asn69IDA (ΔN69), highlighting the importance of the polar interactions between the IDA carboxy-terminus and Arg407HAESA/Arg409HAESA (Figures 1F, 2D).	RESULTS
198	204	Arg407	residue_name_number	We do not detect interaction between HAESA and a synthetic peptide missing the C-terminal Asn69IDA (ΔN69), highlighting the importance of the polar interactions between the IDA carboxy-terminus and Arg407HAESA/Arg409HAESA (Figures 1F, 2D).	RESULTS
204	209	HAESA	protein	We do not detect interaction between HAESA and a synthetic peptide missing the C-terminal Asn69IDA (ΔN69), highlighting the importance of the polar interactions between the IDA carboxy-terminus and Arg407HAESA/Arg409HAESA (Figures 1F, 2D).	RESULTS
210	216	Arg409	residue_name_number	We do not detect interaction between HAESA and a synthetic peptide missing the C-terminal Asn69IDA (ΔN69), highlighting the importance of the polar interactions between the IDA carboxy-terminus and Arg407HAESA/Arg409HAESA (Figures 1F, 2D).	RESULTS
216	221	HAESA	protein	We do not detect interaction between HAESA and a synthetic peptide missing the C-terminal Asn69IDA (ΔN69), highlighting the importance of the polar interactions between the IDA carboxy-terminus and Arg407HAESA/Arg409HAESA (Figures 1F, 2D).	RESULTS
0	9	Replacing	experimental_method	Replacing Hyp64IDA, which is common to all IDLs, with proline impairs the interaction with the receptor, as does the Lys66IDA/Arg67IDA → Ala double-mutant discussed below (Figure 1A, 2D).	RESULTS
10	15	Hyp64	ptm	Replacing Hyp64IDA, which is common to all IDLs, with proline impairs the interaction with the receptor, as does the Lys66IDA/Arg67IDA → Ala double-mutant discussed below (Figure 1A, 2D).	RESULTS
15	18	IDA	protein	Replacing Hyp64IDA, which is common to all IDLs, with proline impairs the interaction with the receptor, as does the Lys66IDA/Arg67IDA → Ala double-mutant discussed below (Figure 1A, 2D).	RESULTS
43	47	IDLs	protein_type	Replacing Hyp64IDA, which is common to all IDLs, with proline impairs the interaction with the receptor, as does the Lys66IDA/Arg67IDA → Ala double-mutant discussed below (Figure 1A, 2D).	RESULTS
54	61	proline	residue_name	Replacing Hyp64IDA, which is common to all IDLs, with proline impairs the interaction with the receptor, as does the Lys66IDA/Arg67IDA → Ala double-mutant discussed below (Figure 1A, 2D).	RESULTS
117	140	Lys66IDA/Arg67IDA → Ala	mutant	Replacing Hyp64IDA, which is common to all IDLs, with proline impairs the interaction with the receptor, as does the Lys66IDA/Arg67IDA → Ala double-mutant discussed below (Figure 1A, 2D).	RESULTS
141	154	double-mutant	protein_state	Replacing Hyp64IDA, which is common to all IDLs, with proline impairs the interaction with the receptor, as does the Lys66IDA/Arg67IDA → Ala double-mutant discussed below (Figure 1A, 2D).	RESULTS
9	14	HAESA	protein	Notably, HAESA can discriminate between IDLs and functionally unrelated dodecamer peptides with Hyp modifications, such as CLV3 (Figures 2D, 7).	RESULTS
40	44	IDLs	protein_type	Notably, HAESA can discriminate between IDLs and functionally unrelated dodecamer peptides with Hyp modifications, such as CLV3 (Figures 2D, 7).	RESULTS
49	71	functionally unrelated	protein_state	Notably, HAESA can discriminate between IDLs and functionally unrelated dodecamer peptides with Hyp modifications, such as CLV3 (Figures 2D, 7).	RESULTS
72	81	dodecamer	structure_element	Notably, HAESA can discriminate between IDLs and functionally unrelated dodecamer peptides with Hyp modifications, such as CLV3 (Figures 2D, 7).	RESULTS
82	90	peptides	chemical	Notably, HAESA can discriminate between IDLs and functionally unrelated dodecamer peptides with Hyp modifications, such as CLV3 (Figures 2D, 7).	RESULTS
96	113	Hyp modifications	ptm	Notably, HAESA can discriminate between IDLs and functionally unrelated dodecamer peptides with Hyp modifications, such as CLV3 (Figures 2D, 7).	RESULTS
123	127	CLV3	protein	Notably, HAESA can discriminate between IDLs and functionally unrelated dodecamer peptides with Hyp modifications, such as CLV3 (Figures 2D, 7).	RESULTS
4	22	co-receptor kinase	protein_type	The co-receptor kinase SERK1 allows for high-affinity IDA sensing	RESULTS
23	28	SERK1	protein	The co-receptor kinase SERK1 allows for high-affinity IDA sensing	RESULTS
4	18	binding assays	experimental_method	Our binding assays reveal that IDA family peptides are sensed by the isolated HAESA ectodomain with relatively weak binding affinities (Figures 1B, 2A–D).	RESULTS
31	50	IDA family peptides	chemical	Our binding assays reveal that IDA family peptides are sensed by the isolated HAESA ectodomain with relatively weak binding affinities (Figures 1B, 2A–D).	RESULTS
69	77	isolated	protein_state	Our binding assays reveal that IDA family peptides are sensed by the isolated HAESA ectodomain with relatively weak binding affinities (Figures 1B, 2A–D).	RESULTS
78	83	HAESA	protein	Our binding assays reveal that IDA family peptides are sensed by the isolated HAESA ectodomain with relatively weak binding affinities (Figures 1B, 2A–D).	RESULTS
84	94	ectodomain	structure_element	Our binding assays reveal that IDA family peptides are sensed by the isolated HAESA ectodomain with relatively weak binding affinities (Figures 1B, 2A–D).	RESULTS
116	134	binding affinities	evidence	Our binding assays reveal that IDA family peptides are sensed by the isolated HAESA ectodomain with relatively weak binding affinities (Figures 1B, 2A–D).	RESULTS
35	73	SOMATIC EMBRYOGENESIS RECEPTOR KINASES	protein_type	It has been recently reported that SOMATIC EMBRYOGENESIS RECEPTOR KINASES (SERKs) are positive regulators of floral abscission and can interact with HAESA and HSL2 in an IDA-dependent manner.	RESULTS
75	80	SERKs	protein_type	It has been recently reported that SOMATIC EMBRYOGENESIS RECEPTOR KINASES (SERKs) are positive regulators of floral abscission and can interact with HAESA and HSL2 in an IDA-dependent manner.	RESULTS
149	154	HAESA	protein	It has been recently reported that SOMATIC EMBRYOGENESIS RECEPTOR KINASES (SERKs) are positive regulators of floral abscission and can interact with HAESA and HSL2 in an IDA-dependent manner.	RESULTS
159	163	HSL2	protein	It has been recently reported that SOMATIC EMBRYOGENESIS RECEPTOR KINASES (SERKs) are positive regulators of floral abscission and can interact with HAESA and HSL2 in an IDA-dependent manner.	RESULTS
12	31	SERK family members	protein_type	As all five SERK family members appear to be expressed in the Arabidopsis abscission zone, we quantified their relative contribution to floral abscission in Arabidopsis using a petal break-strength assay.	RESULTS
62	73	Arabidopsis	taxonomy_domain	As all five SERK family members appear to be expressed in the Arabidopsis abscission zone, we quantified their relative contribution to floral abscission in Arabidopsis using a petal break-strength assay.	RESULTS
157	168	Arabidopsis	taxonomy_domain	As all five SERK family members appear to be expressed in the Arabidopsis abscission zone, we quantified their relative contribution to floral abscission in Arabidopsis using a petal break-strength assay.	RESULTS
177	203	petal break-strength assay	experimental_method	As all five SERK family members appear to be expressed in the Arabidopsis abscission zone, we quantified their relative contribution to floral abscission in Arabidopsis using a petal break-strength assay.	RESULTS
39	58	SERK family members	protein_type	Our experiments suggest that among the SERK family members, SERK1 is a positive regulator of floral abscission.	RESULTS
60	65	SERK1	protein	Our experiments suggest that among the SERK family members, SERK1 is a positive regulator of floral abscission.	RESULTS
57	64	serk1-1	gene	We found that the force required to remove the petals of serk1-1 mutants is significantly higher than that needed for wild-type plants, as previously observed for haesa/hsl2 mutants, and that floral abscission is delayed in serk1-1 (Figure 3A).	RESULTS
65	72	mutants	protein_state	We found that the force required to remove the petals of serk1-1 mutants is significantly higher than that needed for wild-type plants, as previously observed for haesa/hsl2 mutants, and that floral abscission is delayed in serk1-1 (Figure 3A).	RESULTS
118	127	wild-type	protein_state	We found that the force required to remove the petals of serk1-1 mutants is significantly higher than that needed for wild-type plants, as previously observed for haesa/hsl2 mutants, and that floral abscission is delayed in serk1-1 (Figure 3A).	RESULTS
128	134	plants	taxonomy_domain	We found that the force required to remove the petals of serk1-1 mutants is significantly higher than that needed for wild-type plants, as previously observed for haesa/hsl2 mutants, and that floral abscission is delayed in serk1-1 (Figure 3A).	RESULTS
163	168	haesa	gene	We found that the force required to remove the petals of serk1-1 mutants is significantly higher than that needed for wild-type plants, as previously observed for haesa/hsl2 mutants, and that floral abscission is delayed in serk1-1 (Figure 3A).	RESULTS
169	173	hsl2	gene	We found that the force required to remove the petals of serk1-1 mutants is significantly higher than that needed for wild-type plants, as previously observed for haesa/hsl2 mutants, and that floral abscission is delayed in serk1-1 (Figure 3A).	RESULTS
174	181	mutants	protein_state	We found that the force required to remove the petals of serk1-1 mutants is significantly higher than that needed for wild-type plants, as previously observed for haesa/hsl2 mutants, and that floral abscission is delayed in serk1-1 (Figure 3A).	RESULTS
224	231	serk1-1	gene	We found that the force required to remove the petals of serk1-1 mutants is significantly higher than that needed for wild-type plants, as previously observed for haesa/hsl2 mutants, and that floral abscission is delayed in serk1-1 (Figure 3A).	RESULTS
4	11	serk2-2	gene	The serk2-2, serk3-1, serk4-1 and serk5-1 mutant lines showed a petal break-strength profile not significantly different from wild-type plants.	RESULTS
13	20	serk3-1	gene	The serk2-2, serk3-1, serk4-1 and serk5-1 mutant lines showed a petal break-strength profile not significantly different from wild-type plants.	RESULTS
22	29	serk4-1	gene	The serk2-2, serk3-1, serk4-1 and serk5-1 mutant lines showed a petal break-strength profile not significantly different from wild-type plants.	RESULTS
34	41	serk5-1	gene	The serk2-2, serk3-1, serk4-1 and serk5-1 mutant lines showed a petal break-strength profile not significantly different from wild-type plants.	RESULTS
42	48	mutant	protein_state	The serk2-2, serk3-1, serk4-1 and serk5-1 mutant lines showed a petal break-strength profile not significantly different from wild-type plants.	RESULTS
126	135	wild-type	protein_state	The serk2-2, serk3-1, serk4-1 and serk5-1 mutant lines showed a petal break-strength profile not significantly different from wild-type plants.	RESULTS
136	142	plants	taxonomy_domain	The serk2-2, serk3-1, serk4-1 and serk5-1 mutant lines showed a petal break-strength profile not significantly different from wild-type plants.	RESULTS
17	22	SERKs	protein_type	Possibly because SERKs have additional roles in plant development such as in pollen formation and brassinosteroid signaling, we found that higher-order SERK mutants exhibit pleiotropic phenotypes in the flower, rendering their analysis and comparison by quantitative petal break-strength assays difficult.	RESULTS
254	294	quantitative petal break-strength assays	experimental_method	Possibly because SERKs have additional roles in plant development such as in pollen formation and brassinosteroid signaling, we found that higher-order SERK mutants exhibit pleiotropic phenotypes in the flower, rendering their analysis and comparison by quantitative petal break-strength assays difficult.	RESULTS
49	54	SERK1	protein	We thus focused on analyzing the contribution of SERK1 to HAESA ligand sensing and receptor activation.	RESULTS
58	63	HAESA	protein	We thus focused on analyzing the contribution of SERK1 to HAESA ligand sensing and receptor activation.	RESULTS
14	28	LRR ectodomain	structure_element	In vitro, the LRR ectodomain of SERK1 (residues 24–213) forms stable, IDA-dependent heterodimeric complexes with HAESA in size exclusion chromatography experiments (Figure 3B).	RESULTS
32	37	SERK1	protein	In vitro, the LRR ectodomain of SERK1 (residues 24–213) forms stable, IDA-dependent heterodimeric complexes with HAESA in size exclusion chromatography experiments (Figure 3B).	RESULTS
48	54	24–213	residue_range	In vitro, the LRR ectodomain of SERK1 (residues 24–213) forms stable, IDA-dependent heterodimeric complexes with HAESA in size exclusion chromatography experiments (Figure 3B).	RESULTS
62	68	stable	protein_state	In vitro, the LRR ectodomain of SERK1 (residues 24–213) forms stable, IDA-dependent heterodimeric complexes with HAESA in size exclusion chromatography experiments (Figure 3B).	RESULTS
70	83	IDA-dependent	protein_state	In vitro, the LRR ectodomain of SERK1 (residues 24–213) forms stable, IDA-dependent heterodimeric complexes with HAESA in size exclusion chromatography experiments (Figure 3B).	RESULTS
84	97	heterodimeric	oligomeric_state	In vitro, the LRR ectodomain of SERK1 (residues 24–213) forms stable, IDA-dependent heterodimeric complexes with HAESA in size exclusion chromatography experiments (Figure 3B).	RESULTS
98	112	complexes with	protein_state	In vitro, the LRR ectodomain of SERK1 (residues 24–213) forms stable, IDA-dependent heterodimeric complexes with HAESA in size exclusion chromatography experiments (Figure 3B).	RESULTS
113	118	HAESA	protein	In vitro, the LRR ectodomain of SERK1 (residues 24–213) forms stable, IDA-dependent heterodimeric complexes with HAESA in size exclusion chromatography experiments (Figure 3B).	RESULTS
122	151	size exclusion chromatography	experimental_method	In vitro, the LRR ectodomain of SERK1 (residues 24–213) forms stable, IDA-dependent heterodimeric complexes with HAESA in size exclusion chromatography experiments (Figure 3B).	RESULTS
39	44	SERK1	protein	We next quantified the contribution of SERK1 to IDA recognition by HAESA.	RESULTS
48	51	IDA	protein	We next quantified the contribution of SERK1 to IDA recognition by HAESA.	RESULTS
67	72	HAESA	protein	We next quantified the contribution of SERK1 to IDA recognition by HAESA.	RESULTS
14	19	HAESA	protein	We found that HAESA senses IDA with a ~60 fold higher binding affinity in the presence of SERK1, suggesting that SERK1 is involved in the specific recognition of the peptide hormone (Figure 3C).	RESULTS
27	30	IDA	protein	We found that HAESA senses IDA with a ~60 fold higher binding affinity in the presence of SERK1, suggesting that SERK1 is involved in the specific recognition of the peptide hormone (Figure 3C).	RESULTS
54	70	binding affinity	evidence	We found that HAESA senses IDA with a ~60 fold higher binding affinity in the presence of SERK1, suggesting that SERK1 is involved in the specific recognition of the peptide hormone (Figure 3C).	RESULTS
78	89	presence of	protein_state	We found that HAESA senses IDA with a ~60 fold higher binding affinity in the presence of SERK1, suggesting that SERK1 is involved in the specific recognition of the peptide hormone (Figure 3C).	RESULTS
90	95	SERK1	protein	We found that HAESA senses IDA with a ~60 fold higher binding affinity in the presence of SERK1, suggesting that SERK1 is involved in the specific recognition of the peptide hormone (Figure 3C).	RESULTS
113	118	SERK1	protein	We found that HAESA senses IDA with a ~60 fold higher binding affinity in the presence of SERK1, suggesting that SERK1 is involved in the specific recognition of the peptide hormone (Figure 3C).	RESULTS
166	181	peptide hormone	protein_type	We found that HAESA senses IDA with a ~60 fold higher binding affinity in the presence of SERK1, suggesting that SERK1 is involved in the specific recognition of the peptide hormone (Figure 3C).	RESULTS
8	16	titrated	experimental_method	We next titrated SERK1 into a solution containing only the HAESA ectodomain.	RESULTS
17	22	SERK1	protein	We next titrated SERK1 into a solution containing only the HAESA ectodomain.	RESULTS
59	64	HAESA	protein	We next titrated SERK1 into a solution containing only the HAESA ectodomain.	RESULTS
65	75	ectodomain	structure_element	We next titrated SERK1 into a solution containing only the HAESA ectodomain.	RESULTS
97	108	presence of	protein_state	In this case, there was no detectable interaction between receptor and co-receptor, while in the presence of IDA, SERK1 strongly binds HAESA with a dissociation constant in the mid-nanomolar range (Figure 3C).	RESULTS
109	112	IDA	protein	In this case, there was no detectable interaction between receptor and co-receptor, while in the presence of IDA, SERK1 strongly binds HAESA with a dissociation constant in the mid-nanomolar range (Figure 3C).	RESULTS
114	119	SERK1	protein	In this case, there was no detectable interaction between receptor and co-receptor, while in the presence of IDA, SERK1 strongly binds HAESA with a dissociation constant in the mid-nanomolar range (Figure 3C).	RESULTS
135	140	HAESA	protein	In this case, there was no detectable interaction between receptor and co-receptor, while in the presence of IDA, SERK1 strongly binds HAESA with a dissociation constant in the mid-nanomolar range (Figure 3C).	RESULTS
148	169	dissociation constant	evidence	In this case, there was no detectable interaction between receptor and co-receptor, while in the presence of IDA, SERK1 strongly binds HAESA with a dissociation constant in the mid-nanomolar range (Figure 3C).	RESULTS
19	22	IDA	protein	This suggests that IDA itself promotes receptor – co-receptor association, as previously described for the steroid hormone brassinolide and for other LRR-RK complexes.	RESULTS
107	122	steroid hormone	chemical	This suggests that IDA itself promotes receptor – co-receptor association, as previously described for the steroid hormone brassinolide and for other LRR-RK complexes.	RESULTS
123	135	brassinolide	chemical	This suggests that IDA itself promotes receptor – co-receptor association, as previously described for the steroid hormone brassinolide and for other LRR-RK complexes.	RESULTS
150	156	LRR-RK	complex_assembly	This suggests that IDA itself promotes receptor – co-receptor association, as previously described for the steroid hormone brassinolide and for other LRR-RK complexes.	RESULTS
13	31	hydroxyprolination	ptm	Importantly, hydroxyprolination of IDA is critical for HAESA-IDA-SERK1 complex formation (Figure 3C,D).	RESULTS
35	38	IDA	protein	Importantly, hydroxyprolination of IDA is critical for HAESA-IDA-SERK1 complex formation (Figure 3C,D).	RESULTS
55	70	HAESA-IDA-SERK1	complex_assembly	Importantly, hydroxyprolination of IDA is critical for HAESA-IDA-SERK1 complex formation (Figure 3C,D).	RESULTS
4	15	calorimetry	experimental_method	Our calorimetry experiments now reveal that SERKs may render HAESA, and potentially other receptor kinases, competent for high-affinity sensing of their cognate ligands.	RESULTS
44	49	SERKs	protein_type	Our calorimetry experiments now reveal that SERKs may render HAESA, and potentially other receptor kinases, competent for high-affinity sensing of their cognate ligands.	RESULTS
61	66	HAESA	protein	Our calorimetry experiments now reveal that SERKs may render HAESA, and potentially other receptor kinases, competent for high-affinity sensing of their cognate ligands.	RESULTS
90	106	receptor kinases	protein_type	Our calorimetry experiments now reveal that SERKs may render HAESA, and potentially other receptor kinases, competent for high-affinity sensing of their cognate ligands.	RESULTS
5	8	IDA	protein	Upon IDA binding at the cell surface, the kinase domains of HAESA and SERK1, which have been shown to be active protein kinases, may interact in the cytoplasm to activate each other.	RESULTS
42	56	kinase domains	structure_element	Upon IDA binding at the cell surface, the kinase domains of HAESA and SERK1, which have been shown to be active protein kinases, may interact in the cytoplasm to activate each other.	RESULTS
60	65	HAESA	protein	Upon IDA binding at the cell surface, the kinase domains of HAESA and SERK1, which have been shown to be active protein kinases, may interact in the cytoplasm to activate each other.	RESULTS
70	75	SERK1	protein	Upon IDA binding at the cell surface, the kinase domains of HAESA and SERK1, which have been shown to be active protein kinases, may interact in the cytoplasm to activate each other.	RESULTS
105	111	active	protein_state	Upon IDA binding at the cell surface, the kinase domains of HAESA and SERK1, which have been shown to be active protein kinases, may interact in the cytoplasm to activate each other.	RESULTS
112	127	protein kinases	protein_type	Upon IDA binding at the cell surface, the kinase domains of HAESA and SERK1, which have been shown to be active protein kinases, may interact in the cytoplasm to activate each other.	RESULTS
18	23	HAESA	protein	Consistently, the HAESA kinase domain can transphosphorylate SERK1 and vice versa in in vitro transphosphorylation assays (Figure 3E).	RESULTS
24	37	kinase domain	structure_element	Consistently, the HAESA kinase domain can transphosphorylate SERK1 and vice versa in in vitro transphosphorylation assays (Figure 3E).	RESULTS
61	66	SERK1	protein	Consistently, the HAESA kinase domain can transphosphorylate SERK1 and vice versa in in vitro transphosphorylation assays (Figure 3E).	RESULTS
94	121	transphosphorylation assays	experimental_method	Consistently, the HAESA kinase domain can transphosphorylate SERK1 and vice versa in in vitro transphosphorylation assays (Figure 3E).	RESULTS
14	49	genetic and biochemical experiments	experimental_method	Together, our genetic and biochemical experiments implicate SERK1 as a HAESA co-receptor in the Arabidopsis abscission zone.	RESULTS
60	65	SERK1	protein	Together, our genetic and biochemical experiments implicate SERK1 as a HAESA co-receptor in the Arabidopsis abscission zone.	RESULTS
71	88	HAESA co-receptor	protein_type	Together, our genetic and biochemical experiments implicate SERK1 as a HAESA co-receptor in the Arabidopsis abscission zone.	RESULTS
96	107	Arabidopsis	taxonomy_domain	Together, our genetic and biochemical experiments implicate SERK1 as a HAESA co-receptor in the Arabidopsis abscission zone.	RESULTS
0	5	SERK1	protein	SERK1 senses a conserved motif in IDA family peptides	RESULTS
15	24	conserved	protein_state	SERK1 senses a conserved motif in IDA family peptides	RESULTS
25	30	motif	structure_element	SERK1 senses a conserved motif in IDA family peptides	RESULTS
34	53	IDA family peptides	chemical	SERK1 senses a conserved motif in IDA family peptides	RESULTS
0	17	Crystal structure	evidence	Crystal structure of a HAESA – IDA – SERK1 signaling complex.	FIG
23	42	HAESA – IDA – SERK1	complex_assembly	Crystal structure of a HAESA – IDA – SERK1 signaling complex.	FIG
41	46	HAESA	protein	(A) Overview of the ternary complex with HAESA in blue (surface representation), IDA in yellow (bonds representation) and SERK1 in orange (surface view). (B) The HAESA ectodomain undergoes a conformational change upon SERK1 co-receptor binding.	FIG
81	84	IDA	protein	(A) Overview of the ternary complex with HAESA in blue (surface representation), IDA in yellow (bonds representation) and SERK1 in orange (surface view). (B) The HAESA ectodomain undergoes a conformational change upon SERK1 co-receptor binding.	FIG
122	127	SERK1	protein	(A) Overview of the ternary complex with HAESA in blue (surface representation), IDA in yellow (bonds representation) and SERK1 in orange (surface view). (B) The HAESA ectodomain undergoes a conformational change upon SERK1 co-receptor binding.	FIG
162	167	HAESA	protein	(A) Overview of the ternary complex with HAESA in blue (surface representation), IDA in yellow (bonds representation) and SERK1 in orange (surface view). (B) The HAESA ectodomain undergoes a conformational change upon SERK1 co-receptor binding.	FIG
168	178	ectodomain	structure_element	(A) Overview of the ternary complex with HAESA in blue (surface representation), IDA in yellow (bonds representation) and SERK1 in orange (surface view). (B) The HAESA ectodomain undergoes a conformational change upon SERK1 co-receptor binding.	FIG
218	223	SERK1	protein	(A) Overview of the ternary complex with HAESA in blue (surface representation), IDA in yellow (bonds representation) and SERK1 in orange (surface view). (B) The HAESA ectodomain undergoes a conformational change upon SERK1 co-receptor binding.	FIG
25	49	structural superposition	experimental_method	Shown are Cα traces of a structural superposition of the unbound (yellow) and SERK1-bound (blue) HAESA ectodomains (r.m.s.d. is 1.5 Å between 572 corresponding Cα atoms).	FIG
57	64	unbound	protein_state	Shown are Cα traces of a structural superposition of the unbound (yellow) and SERK1-bound (blue) HAESA ectodomains (r.m.s.d. is 1.5 Å between 572 corresponding Cα atoms).	FIG
78	89	SERK1-bound	protein_state	Shown are Cα traces of a structural superposition of the unbound (yellow) and SERK1-bound (blue) HAESA ectodomains (r.m.s.d. is 1.5 Å between 572 corresponding Cα atoms).	FIG
97	102	HAESA	protein	Shown are Cα traces of a structural superposition of the unbound (yellow) and SERK1-bound (blue) HAESA ectodomains (r.m.s.d. is 1.5 Å between 572 corresponding Cα atoms).	FIG
103	114	ectodomains	structure_element	Shown are Cα traces of a structural superposition of the unbound (yellow) and SERK1-bound (blue) HAESA ectodomains (r.m.s.d. is 1.5 Å between 572 corresponding Cα atoms).	FIG
116	124	r.m.s.d.	evidence	Shown are Cα traces of a structural superposition of the unbound (yellow) and SERK1-bound (blue) HAESA ectodomains (r.m.s.d. is 1.5 Å between 572 corresponding Cα atoms).	FIG
0	5	SERK1	protein	SERK1 (in orange) and IDA (in red) are shown alongside.	FIG
22	25	IDA	protein	SERK1 (in orange) and IDA (in red) are shown alongside.	FIG
44	48	LRRs	structure_element	The conformational change in the C-terminal LRRs and capping domain is indicated by an arrow. (C) SERK1 forms an integral part of the receptor's peptide binding pocket.	FIG
53	67	capping domain	structure_element	The conformational change in the C-terminal LRRs and capping domain is indicated by an arrow. (C) SERK1 forms an integral part of the receptor's peptide binding pocket.	FIG
98	103	SERK1	protein	The conformational change in the C-terminal LRRs and capping domain is indicated by an arrow. (C) SERK1 forms an integral part of the receptor's peptide binding pocket.	FIG
145	167	peptide binding pocket	site	The conformational change in the C-terminal LRRs and capping domain is indicated by an arrow. (C) SERK1 forms an integral part of the receptor's peptide binding pocket.	FIG
15	29	capping domain	structure_element	The N-terminal capping domain of SERK1 (in orange) directly contacts the C-terminal part of IDA (in yellow, in bonds representation) and the receptor HAESA (in blue).	FIG
33	38	SERK1	protein	The N-terminal capping domain of SERK1 (in orange) directly contacts the C-terminal part of IDA (in yellow, in bonds representation) and the receptor HAESA (in blue).	FIG
92	95	IDA	protein	The N-terminal capping domain of SERK1 (in orange) directly contacts the C-terminal part of IDA (in yellow, in bonds representation) and the receptor HAESA (in blue).	FIG
141	149	receptor	protein_type	The N-terminal capping domain of SERK1 (in orange) directly contacts the C-terminal part of IDA (in yellow, in bonds representation) and the receptor HAESA (in blue).	FIG
150	155	HAESA	protein	The N-terminal capping domain of SERK1 (in orange) directly contacts the C-terminal part of IDA (in yellow, in bonds representation) and the receptor HAESA (in blue).	FIG
0	14	Polar contacts	bond_interaction	Polar contacts of SERK1 with IDA are shown in magenta, with the HAESA LRR domain in gray. (D) Details of the zipper-like SERK1-HAESA interface.	FIG
18	23	SERK1	protein	Polar contacts of SERK1 with IDA are shown in magenta, with the HAESA LRR domain in gray. (D) Details of the zipper-like SERK1-HAESA interface.	FIG
29	32	IDA	protein	Polar contacts of SERK1 with IDA are shown in magenta, with the HAESA LRR domain in gray. (D) Details of the zipper-like SERK1-HAESA interface.	FIG
64	69	HAESA	protein	Polar contacts of SERK1 with IDA are shown in magenta, with the HAESA LRR domain in gray. (D) Details of the zipper-like SERK1-HAESA interface.	FIG
70	80	LRR domain	structure_element	Polar contacts of SERK1 with IDA are shown in magenta, with the HAESA LRR domain in gray. (D) Details of the zipper-like SERK1-HAESA interface.	FIG
109	120	zipper-like	structure_element	Polar contacts of SERK1 with IDA are shown in magenta, with the HAESA LRR domain in gray. (D) Details of the zipper-like SERK1-HAESA interface.	FIG
121	142	SERK1-HAESA interface	site	Polar contacts of SERK1 with IDA are shown in magenta, with the HAESA LRR domain in gray. (D) Details of the zipper-like SERK1-HAESA interface.	FIG
19	24	HAESA	protein	Ribbon diagrams of HAESA (in blue) and SERK1 (in orange) are shown with selected interface residues (in bonds representation).	FIG
39	44	SERK1	protein	Ribbon diagrams of HAESA (in blue) and SERK1 (in orange) are shown with selected interface residues (in bonds representation).	FIG
81	99	interface residues	site	Ribbon diagrams of HAESA (in blue) and SERK1 (in orange) are shown with selected interface residues (in bonds representation).	FIG
0	18	Polar interactions	bond_interaction	Polar interactions are highlighted as dotted lines (in magenta).	FIG
37	42	SERK1	protein	To understand in molecular terms how SERK1 contributes to high-affinity IDA recognition, we solved a 2.43 Å crystal structure of the ternary HAESA – IDA – SERK1 complex (Figure 4A, Table 2).	RESULTS
72	75	IDA	protein	To understand in molecular terms how SERK1 contributes to high-affinity IDA recognition, we solved a 2.43 Å crystal structure of the ternary HAESA – IDA – SERK1 complex (Figure 4A, Table 2).	RESULTS
108	125	crystal structure	evidence	To understand in molecular terms how SERK1 contributes to high-affinity IDA recognition, we solved a 2.43 Å crystal structure of the ternary HAESA – IDA – SERK1 complex (Figure 4A, Table 2).	RESULTS
141	160	HAESA – IDA – SERK1	complex_assembly	To understand in molecular terms how SERK1 contributes to high-affinity IDA recognition, we solved a 2.43 Å crystal structure of the ternary HAESA – IDA – SERK1 complex (Figure 4A, Table 2).	RESULTS
0	5	HAESA	protein	HAESA LRRs 16–21 and its C-terminal capping domain undergo a conformational change upon SERK1 binding (Figure 4B).	RESULTS
6	16	LRRs 16–21	structure_element	HAESA LRRs 16–21 and its C-terminal capping domain undergo a conformational change upon SERK1 binding (Figure 4B).	RESULTS
36	50	capping domain	structure_element	HAESA LRRs 16–21 and its C-terminal capping domain undergo a conformational change upon SERK1 binding (Figure 4B).	RESULTS
88	93	SERK1	protein	HAESA LRRs 16–21 and its C-terminal capping domain undergo a conformational change upon SERK1 binding (Figure 4B).	RESULTS
4	9	SERK1	protein	The SERK1 ectodomain interacts with the IDA peptide binding site using a loop region (residues 51-59SERK1) from its N-terminal cap (Figure 4A,C).	RESULTS
10	20	ectodomain	structure_element	The SERK1 ectodomain interacts with the IDA peptide binding site using a loop region (residues 51-59SERK1) from its N-terminal cap (Figure 4A,C).	RESULTS
40	64	IDA peptide binding site	site	The SERK1 ectodomain interacts with the IDA peptide binding site using a loop region (residues 51-59SERK1) from its N-terminal cap (Figure 4A,C).	RESULTS
73	84	loop region	structure_element	The SERK1 ectodomain interacts with the IDA peptide binding site using a loop region (residues 51-59SERK1) from its N-terminal cap (Figure 4A,C).	RESULTS
95	100	51-59	residue_range	The SERK1 ectodomain interacts with the IDA peptide binding site using a loop region (residues 51-59SERK1) from its N-terminal cap (Figure 4A,C).	RESULTS
100	105	SERK1	protein	The SERK1 ectodomain interacts with the IDA peptide binding site using a loop region (residues 51-59SERK1) from its N-terminal cap (Figure 4A,C).	RESULTS
127	130	cap	structure_element	The SERK1 ectodomain interacts with the IDA peptide binding site using a loop region (residues 51-59SERK1) from its N-terminal cap (Figure 4A,C).	RESULTS
0	5	SERK1	protein	SERK1 loop residues establish multiple hydrophobic and polar contacts with Lys66IDA and the C-terminal Arg-His-Asn motif in IDA (Figure 4C).	RESULTS
6	10	loop	structure_element	SERK1 loop residues establish multiple hydrophobic and polar contacts with Lys66IDA and the C-terminal Arg-His-Asn motif in IDA (Figure 4C).	RESULTS
39	69	hydrophobic and polar contacts	bond_interaction	SERK1 loop residues establish multiple hydrophobic and polar contacts with Lys66IDA and the C-terminal Arg-His-Asn motif in IDA (Figure 4C).	RESULTS
75	80	Lys66	residue_name_number	SERK1 loop residues establish multiple hydrophobic and polar contacts with Lys66IDA and the C-terminal Arg-His-Asn motif in IDA (Figure 4C).	RESULTS
80	83	IDA	protein	SERK1 loop residues establish multiple hydrophobic and polar contacts with Lys66IDA and the C-terminal Arg-His-Asn motif in IDA (Figure 4C).	RESULTS
103	120	Arg-His-Asn motif	structure_element	SERK1 loop residues establish multiple hydrophobic and polar contacts with Lys66IDA and the C-terminal Arg-His-Asn motif in IDA (Figure 4C).	RESULTS
124	127	IDA	protein	SERK1 loop residues establish multiple hydrophobic and polar contacts with Lys66IDA and the C-terminal Arg-His-Asn motif in IDA (Figure 4C).	RESULTS
0	5	SERK1	protein	SERK1 LRRs 1–5 and its C-terminal capping domain form an additional zipper-like interface with residues originating from HAESA LRRs 15–21 and from the HAESA C-terminal cap (Figure 4D).	RESULTS
6	14	LRRs 1–5	structure_element	SERK1 LRRs 1–5 and its C-terminal capping domain form an additional zipper-like interface with residues originating from HAESA LRRs 15–21 and from the HAESA C-terminal cap (Figure 4D).	RESULTS
34	48	capping domain	structure_element	SERK1 LRRs 1–5 and its C-terminal capping domain form an additional zipper-like interface with residues originating from HAESA LRRs 15–21 and from the HAESA C-terminal cap (Figure 4D).	RESULTS
68	79	zipper-like	structure_element	SERK1 LRRs 1–5 and its C-terminal capping domain form an additional zipper-like interface with residues originating from HAESA LRRs 15–21 and from the HAESA C-terminal cap (Figure 4D).	RESULTS
80	89	interface	site	SERK1 LRRs 1–5 and its C-terminal capping domain form an additional zipper-like interface with residues originating from HAESA LRRs 15–21 and from the HAESA C-terminal cap (Figure 4D).	RESULTS
121	126	HAESA	protein	SERK1 LRRs 1–5 and its C-terminal capping domain form an additional zipper-like interface with residues originating from HAESA LRRs 15–21 and from the HAESA C-terminal cap (Figure 4D).	RESULTS
127	137	LRRs 15–21	structure_element	SERK1 LRRs 1–5 and its C-terminal capping domain form an additional zipper-like interface with residues originating from HAESA LRRs 15–21 and from the HAESA C-terminal cap (Figure 4D).	RESULTS
151	156	HAESA	protein	SERK1 LRRs 1–5 and its C-terminal capping domain form an additional zipper-like interface with residues originating from HAESA LRRs 15–21 and from the HAESA C-terminal cap (Figure 4D).	RESULTS
168	171	cap	structure_element	SERK1 LRRs 1–5 and its C-terminal capping domain form an additional zipper-like interface with residues originating from HAESA LRRs 15–21 and from the HAESA C-terminal cap (Figure 4D).	RESULTS
0	5	SERK1	protein	SERK1 binds HAESA using these two distinct interaction surfaces (Figure 1—figure supplement 3), with the N-cap of the SERK1 LRR domain partially covering the IDA peptide binding cleft.	RESULTS
12	17	HAESA	protein	SERK1 binds HAESA using these two distinct interaction surfaces (Figure 1—figure supplement 3), with the N-cap of the SERK1 LRR domain partially covering the IDA peptide binding cleft.	RESULTS
43	63	interaction surfaces	site	SERK1 binds HAESA using these two distinct interaction surfaces (Figure 1—figure supplement 3), with the N-cap of the SERK1 LRR domain partially covering the IDA peptide binding cleft.	RESULTS
105	110	N-cap	structure_element	SERK1 binds HAESA using these two distinct interaction surfaces (Figure 1—figure supplement 3), with the N-cap of the SERK1 LRR domain partially covering the IDA peptide binding cleft.	RESULTS
118	123	SERK1	protein	SERK1 binds HAESA using these two distinct interaction surfaces (Figure 1—figure supplement 3), with the N-cap of the SERK1 LRR domain partially covering the IDA peptide binding cleft.	RESULTS
124	134	LRR domain	structure_element	SERK1 binds HAESA using these two distinct interaction surfaces (Figure 1—figure supplement 3), with the N-cap of the SERK1 LRR domain partially covering the IDA peptide binding cleft.	RESULTS
158	183	IDA peptide binding cleft	site	SERK1 binds HAESA using these two distinct interaction surfaces (Figure 1—figure supplement 3), with the N-cap of the SERK1 LRR domain partially covering the IDA peptide binding cleft.	RESULTS
4	7	IDA	protein	The IDA C-terminal motif is required for HAESA-SERK1 complex formation and for IDA bioactivity.	FIG
8	24	C-terminal motif	structure_element	The IDA C-terminal motif is required for HAESA-SERK1 complex formation and for IDA bioactivity.	FIG
41	52	HAESA-SERK1	complex_assembly	The IDA C-terminal motif is required for HAESA-SERK1 complex formation and for IDA bioactivity.	FIG
4	33	Size exclusion chromatography	experimental_method	(A) Size exclusion chromatography experiments similar to Figure 3B,D reveal that IDA mutant peptides targeting the C-terminal motif do not form biochemically stable HAESA-IDA-SERK1 complexes.	FIG
81	84	IDA	protein	(A) Size exclusion chromatography experiments similar to Figure 3B,D reveal that IDA mutant peptides targeting the C-terminal motif do not form biochemically stable HAESA-IDA-SERK1 complexes.	FIG
85	91	mutant	protein_state	(A) Size exclusion chromatography experiments similar to Figure 3B,D reveal that IDA mutant peptides targeting the C-terminal motif do not form biochemically stable HAESA-IDA-SERK1 complexes.	FIG
92	100	peptides	chemical	(A) Size exclusion chromatography experiments similar to Figure 3B,D reveal that IDA mutant peptides targeting the C-terminal motif do not form biochemically stable HAESA-IDA-SERK1 complexes.	FIG
115	131	C-terminal motif	structure_element	(A) Size exclusion chromatography experiments similar to Figure 3B,D reveal that IDA mutant peptides targeting the C-terminal motif do not form biochemically stable HAESA-IDA-SERK1 complexes.	FIG
144	164	biochemically stable	protein_state	(A) Size exclusion chromatography experiments similar to Figure 3B,D reveal that IDA mutant peptides targeting the C-terminal motif do not form biochemically stable HAESA-IDA-SERK1 complexes.	FIG
165	180	HAESA-IDA-SERK1	complex_assembly	(A) Size exclusion chromatography experiments similar to Figure 3B,D reveal that IDA mutant peptides targeting the C-terminal motif do not form biochemically stable HAESA-IDA-SERK1 complexes.	FIG
0	8	Deletion	experimental_method	Deletion of the C-terminal Asn69IDA completely inhibits complex formation.	FIG
27	32	Asn69	residue_name_number	Deletion of the C-terminal Asn69IDA completely inhibits complex formation.	FIG
32	35	IDA	protein	Deletion of the C-terminal Asn69IDA completely inhibits complex formation.	FIG
47	55	inhibits	protein_state	Deletion of the C-terminal Asn69IDA completely inhibits complex formation.	FIG
0	8	Purified	experimental_method	Purified HAESA and SERK1 are ~75 and ~28 kDa, respectively.	FIG
9	14	HAESA	protein	Purified HAESA and SERK1 are ~75 and ~28 kDa, respectively.	FIG
19	24	SERK1	protein	Purified HAESA and SERK1 are ~75 and ~28 kDa, respectively.	FIG
12	25	IDA K66A/R67A	mutant	Left panel: IDA K66A/R67A; center: IDA ΔN69, right panel: SDS-PAGE of peak fractions.	FIG
35	43	IDA ΔN69	mutant	Left panel: IDA K66A/R67A; center: IDA ΔN69, right panel: SDS-PAGE of peak fractions.	FIG
58	66	SDS-PAGE	experimental_method	Left panel: IDA K66A/R67A; center: IDA ΔN69, right panel: SDS-PAGE of peak fractions.	FIG
14	19	HAESA	protein	Note that the HAESA and SERK1 input lanes have already been shown in Figure 3D. (B) Isothermal titration thermographs of wild-type and mutant IDA peptides titrated into a HAESA - SERK1 mixture in the cell.	FIG
24	29	SERK1	protein	Note that the HAESA and SERK1 input lanes have already been shown in Figure 3D. (B) Isothermal titration thermographs of wild-type and mutant IDA peptides titrated into a HAESA - SERK1 mixture in the cell.	FIG
84	117	Isothermal titration thermographs	evidence	Note that the HAESA and SERK1 input lanes have already been shown in Figure 3D. (B) Isothermal titration thermographs of wild-type and mutant IDA peptides titrated into a HAESA - SERK1 mixture in the cell.	FIG
121	130	wild-type	protein_state	Note that the HAESA and SERK1 input lanes have already been shown in Figure 3D. (B) Isothermal titration thermographs of wild-type and mutant IDA peptides titrated into a HAESA - SERK1 mixture in the cell.	FIG
135	141	mutant	protein_state	Note that the HAESA and SERK1 input lanes have already been shown in Figure 3D. (B) Isothermal titration thermographs of wild-type and mutant IDA peptides titrated into a HAESA - SERK1 mixture in the cell.	FIG
142	154	IDA peptides	chemical	Note that the HAESA and SERK1 input lanes have already been shown in Figure 3D. (B) Isothermal titration thermographs of wild-type and mutant IDA peptides titrated into a HAESA - SERK1 mixture in the cell.	FIG
155	163	titrated	experimental_method	Note that the HAESA and SERK1 input lanes have already been shown in Figure 3D. (B) Isothermal titration thermographs of wild-type and mutant IDA peptides titrated into a HAESA - SERK1 mixture in the cell.	FIG
171	176	HAESA	protein	Note that the HAESA and SERK1 input lanes have already been shown in Figure 3D. (B) Isothermal titration thermographs of wild-type and mutant IDA peptides titrated into a HAESA - SERK1 mixture in the cell.	FIG
179	184	SERK1	protein	Note that the HAESA and SERK1 input lanes have already been shown in Figure 3D. (B) Isothermal titration thermographs of wild-type and mutant IDA peptides titrated into a HAESA - SERK1 mixture in the cell.	FIG
20	50	calorimetric binding constants	evidence	Table summaries for calorimetric binding constants and stoichoimetries for different IDA peptides binding to the HAESA – SERK1 ectodomain mixture ( ± fitting errors; n.d.	FIG
85	97	IDA peptides	chemical	Table summaries for calorimetric binding constants and stoichoimetries for different IDA peptides binding to the HAESA – SERK1 ectodomain mixture ( ± fitting errors; n.d.	FIG
113	118	HAESA	protein	Table summaries for calorimetric binding constants and stoichoimetries for different IDA peptides binding to the HAESA – SERK1 ectodomain mixture ( ± fitting errors; n.d.	FIG
121	126	SERK1	protein	Table summaries for calorimetric binding constants and stoichoimetries for different IDA peptides binding to the HAESA – SERK1 ectodomain mixture ( ± fitting errors; n.d.	FIG
127	137	ectodomain	structure_element	Table summaries for calorimetric binding constants and stoichoimetries for different IDA peptides binding to the HAESA – SERK1 ectodomain mixture ( ± fitting errors; n.d.	FIG
17	43	petal break-strength assay	experimental_method	(C) Quantitative petal break-strength assay for Col-0 wild-type flowers and 35S::IDA wild-type and 35S::IDA K66A/R67A mutant flowers.	FIG
54	63	wild-type	protein_state	(C) Quantitative petal break-strength assay for Col-0 wild-type flowers and 35S::IDA wild-type and 35S::IDA K66A/R67A mutant flowers.	FIG
76	79	35S	gene	(C) Quantitative petal break-strength assay for Col-0 wild-type flowers and 35S::IDA wild-type and 35S::IDA K66A/R67A mutant flowers.	FIG
81	84	IDA	protein	(C) Quantitative petal break-strength assay for Col-0 wild-type flowers and 35S::IDA wild-type and 35S::IDA K66A/R67A mutant flowers.	FIG
85	94	wild-type	protein_state	(C) Quantitative petal break-strength assay for Col-0 wild-type flowers and 35S::IDA wild-type and 35S::IDA K66A/R67A mutant flowers.	FIG
99	102	35S	gene	(C) Quantitative petal break-strength assay for Col-0 wild-type flowers and 35S::IDA wild-type and 35S::IDA K66A/R67A mutant flowers.	FIG
104	117	IDA K66A/R67A	mutant	(C) Quantitative petal break-strength assay for Col-0 wild-type flowers and 35S::IDA wild-type and 35S::IDA K66A/R67A mutant flowers.	FIG
118	124	mutant	protein_state	(C) Quantitative petal break-strength assay for Col-0 wild-type flowers and 35S::IDA wild-type and 35S::IDA K66A/R67A mutant flowers.	FIG
0	3	35S	gene	35S::IDA plants showed significantly increased abscission compared to Col-0 controls in inflorescence positions 2 and 3 (a).	FIG
5	8	IDA	protein	35S::IDA plants showed significantly increased abscission compared to Col-0 controls in inflorescence positions 2 and 3 (a).	FIG
9	15	plants	taxonomy_domain	35S::IDA plants showed significantly increased abscission compared to Col-0 controls in inflorescence positions 2 and 3 (a).	FIG
47	50	35S	gene	Up to inflorescence position 4, petal break in 35S::IDA K66A/R67A mutant plants was significantly increased compared to both Col-0 control plants (b) and 35S::IDA plants (c) (D) Normalized expression levels (relative expression ± standard error; ida: -0.02 ± 0.001; Col-0: 1 ± 0.11; 35S::IDA 124 ± 0.75; 35S::IDA K66A/R67A: 159 ± 0.58) of IDA wild-type and mutant transcripts in the 35S promoter over-expression lines analyzed in (C). (E) Magnified view of representative abscission zones from 35S::IDA, Col-0 wild-type and 35S::IDA K66A/R67A double-mutant T3 transgenic lines.	FIG
52	65	IDA K66A/R67A	mutant	Up to inflorescence position 4, petal break in 35S::IDA K66A/R67A mutant plants was significantly increased compared to both Col-0 control plants (b) and 35S::IDA plants (c) (D) Normalized expression levels (relative expression ± standard error; ida: -0.02 ± 0.001; Col-0: 1 ± 0.11; 35S::IDA 124 ± 0.75; 35S::IDA K66A/R67A: 159 ± 0.58) of IDA wild-type and mutant transcripts in the 35S promoter over-expression lines analyzed in (C). (E) Magnified view of representative abscission zones from 35S::IDA, Col-0 wild-type and 35S::IDA K66A/R67A double-mutant T3 transgenic lines.	FIG
66	72	mutant	protein_state	Up to inflorescence position 4, petal break in 35S::IDA K66A/R67A mutant plants was significantly increased compared to both Col-0 control plants (b) and 35S::IDA plants (c) (D) Normalized expression levels (relative expression ± standard error; ida: -0.02 ± 0.001; Col-0: 1 ± 0.11; 35S::IDA 124 ± 0.75; 35S::IDA K66A/R67A: 159 ± 0.58) of IDA wild-type and mutant transcripts in the 35S promoter over-expression lines analyzed in (C). (E) Magnified view of representative abscission zones from 35S::IDA, Col-0 wild-type and 35S::IDA K66A/R67A double-mutant T3 transgenic lines.	FIG
73	79	plants	taxonomy_domain	Up to inflorescence position 4, petal break in 35S::IDA K66A/R67A mutant plants was significantly increased compared to both Col-0 control plants (b) and 35S::IDA plants (c) (D) Normalized expression levels (relative expression ± standard error; ida: -0.02 ± 0.001; Col-0: 1 ± 0.11; 35S::IDA 124 ± 0.75; 35S::IDA K66A/R67A: 159 ± 0.58) of IDA wild-type and mutant transcripts in the 35S promoter over-expression lines analyzed in (C). (E) Magnified view of representative abscission zones from 35S::IDA, Col-0 wild-type and 35S::IDA K66A/R67A double-mutant T3 transgenic lines.	FIG
139	145	plants	taxonomy_domain	Up to inflorescence position 4, petal break in 35S::IDA K66A/R67A mutant plants was significantly increased compared to both Col-0 control plants (b) and 35S::IDA plants (c) (D) Normalized expression levels (relative expression ± standard error; ida: -0.02 ± 0.001; Col-0: 1 ± 0.11; 35S::IDA 124 ± 0.75; 35S::IDA K66A/R67A: 159 ± 0.58) of IDA wild-type and mutant transcripts in the 35S promoter over-expression lines analyzed in (C). (E) Magnified view of representative abscission zones from 35S::IDA, Col-0 wild-type and 35S::IDA K66A/R67A double-mutant T3 transgenic lines.	FIG
154	157	35S	gene	Up to inflorescence position 4, petal break in 35S::IDA K66A/R67A mutant plants was significantly increased compared to both Col-0 control plants (b) and 35S::IDA plants (c) (D) Normalized expression levels (relative expression ± standard error; ida: -0.02 ± 0.001; Col-0: 1 ± 0.11; 35S::IDA 124 ± 0.75; 35S::IDA K66A/R67A: 159 ± 0.58) of IDA wild-type and mutant transcripts in the 35S promoter over-expression lines analyzed in (C). (E) Magnified view of representative abscission zones from 35S::IDA, Col-0 wild-type and 35S::IDA K66A/R67A double-mutant T3 transgenic lines.	FIG
159	162	IDA	protein	Up to inflorescence position 4, petal break in 35S::IDA K66A/R67A mutant plants was significantly increased compared to both Col-0 control plants (b) and 35S::IDA plants (c) (D) Normalized expression levels (relative expression ± standard error; ida: -0.02 ± 0.001; Col-0: 1 ± 0.11; 35S::IDA 124 ± 0.75; 35S::IDA K66A/R67A: 159 ± 0.58) of IDA wild-type and mutant transcripts in the 35S promoter over-expression lines analyzed in (C). (E) Magnified view of representative abscission zones from 35S::IDA, Col-0 wild-type and 35S::IDA K66A/R67A double-mutant T3 transgenic lines.	FIG
163	169	plants	taxonomy_domain	Up to inflorescence position 4, petal break in 35S::IDA K66A/R67A mutant plants was significantly increased compared to both Col-0 control plants (b) and 35S::IDA plants (c) (D) Normalized expression levels (relative expression ± standard error; ida: -0.02 ± 0.001; Col-0: 1 ± 0.11; 35S::IDA 124 ± 0.75; 35S::IDA K66A/R67A: 159 ± 0.58) of IDA wild-type and mutant transcripts in the 35S promoter over-expression lines analyzed in (C). (E) Magnified view of representative abscission zones from 35S::IDA, Col-0 wild-type and 35S::IDA K66A/R67A double-mutant T3 transgenic lines.	FIG
283	286	35S	gene	Up to inflorescence position 4, petal break in 35S::IDA K66A/R67A mutant plants was significantly increased compared to both Col-0 control plants (b) and 35S::IDA plants (c) (D) Normalized expression levels (relative expression ± standard error; ida: -0.02 ± 0.001; Col-0: 1 ± 0.11; 35S::IDA 124 ± 0.75; 35S::IDA K66A/R67A: 159 ± 0.58) of IDA wild-type and mutant transcripts in the 35S promoter over-expression lines analyzed in (C). (E) Magnified view of representative abscission zones from 35S::IDA, Col-0 wild-type and 35S::IDA K66A/R67A double-mutant T3 transgenic lines.	FIG
288	291	IDA	protein	Up to inflorescence position 4, petal break in 35S::IDA K66A/R67A mutant plants was significantly increased compared to both Col-0 control plants (b) and 35S::IDA plants (c) (D) Normalized expression levels (relative expression ± standard error; ida: -0.02 ± 0.001; Col-0: 1 ± 0.11; 35S::IDA 124 ± 0.75; 35S::IDA K66A/R67A: 159 ± 0.58) of IDA wild-type and mutant transcripts in the 35S promoter over-expression lines analyzed in (C). (E) Magnified view of representative abscission zones from 35S::IDA, Col-0 wild-type and 35S::IDA K66A/R67A double-mutant T3 transgenic lines.	FIG
304	307	35S	gene	Up to inflorescence position 4, petal break in 35S::IDA K66A/R67A mutant plants was significantly increased compared to both Col-0 control plants (b) and 35S::IDA plants (c) (D) Normalized expression levels (relative expression ± standard error; ida: -0.02 ± 0.001; Col-0: 1 ± 0.11; 35S::IDA 124 ± 0.75; 35S::IDA K66A/R67A: 159 ± 0.58) of IDA wild-type and mutant transcripts in the 35S promoter over-expression lines analyzed in (C). (E) Magnified view of representative abscission zones from 35S::IDA, Col-0 wild-type and 35S::IDA K66A/R67A double-mutant T3 transgenic lines.	FIG
309	322	IDA K66A/R67A	mutant	Up to inflorescence position 4, petal break in 35S::IDA K66A/R67A mutant plants was significantly increased compared to both Col-0 control plants (b) and 35S::IDA plants (c) (D) Normalized expression levels (relative expression ± standard error; ida: -0.02 ± 0.001; Col-0: 1 ± 0.11; 35S::IDA 124 ± 0.75; 35S::IDA K66A/R67A: 159 ± 0.58) of IDA wild-type and mutant transcripts in the 35S promoter over-expression lines analyzed in (C). (E) Magnified view of representative abscission zones from 35S::IDA, Col-0 wild-type and 35S::IDA K66A/R67A double-mutant T3 transgenic lines.	FIG
339	342	IDA	protein	Up to inflorescence position 4, petal break in 35S::IDA K66A/R67A mutant plants was significantly increased compared to both Col-0 control plants (b) and 35S::IDA plants (c) (D) Normalized expression levels (relative expression ± standard error; ida: -0.02 ± 0.001; Col-0: 1 ± 0.11; 35S::IDA 124 ± 0.75; 35S::IDA K66A/R67A: 159 ± 0.58) of IDA wild-type and mutant transcripts in the 35S promoter over-expression lines analyzed in (C). (E) Magnified view of representative abscission zones from 35S::IDA, Col-0 wild-type and 35S::IDA K66A/R67A double-mutant T3 transgenic lines.	FIG
343	352	wild-type	protein_state	Up to inflorescence position 4, petal break in 35S::IDA K66A/R67A mutant plants was significantly increased compared to both Col-0 control plants (b) and 35S::IDA plants (c) (D) Normalized expression levels (relative expression ± standard error; ida: -0.02 ± 0.001; Col-0: 1 ± 0.11; 35S::IDA 124 ± 0.75; 35S::IDA K66A/R67A: 159 ± 0.58) of IDA wild-type and mutant transcripts in the 35S promoter over-expression lines analyzed in (C). (E) Magnified view of representative abscission zones from 35S::IDA, Col-0 wild-type and 35S::IDA K66A/R67A double-mutant T3 transgenic lines.	FIG
357	363	mutant	protein_state	Up to inflorescence position 4, petal break in 35S::IDA K66A/R67A mutant plants was significantly increased compared to both Col-0 control plants (b) and 35S::IDA plants (c) (D) Normalized expression levels (relative expression ± standard error; ida: -0.02 ± 0.001; Col-0: 1 ± 0.11; 35S::IDA 124 ± 0.75; 35S::IDA K66A/R67A: 159 ± 0.58) of IDA wild-type and mutant transcripts in the 35S promoter over-expression lines analyzed in (C). (E) Magnified view of representative abscission zones from 35S::IDA, Col-0 wild-type and 35S::IDA K66A/R67A double-mutant T3 transgenic lines.	FIG
383	417	35S promoter over-expression lines	experimental_method	Up to inflorescence position 4, petal break in 35S::IDA K66A/R67A mutant plants was significantly increased compared to both Col-0 control plants (b) and 35S::IDA plants (c) (D) Normalized expression levels (relative expression ± standard error; ida: -0.02 ± 0.001; Col-0: 1 ± 0.11; 35S::IDA 124 ± 0.75; 35S::IDA K66A/R67A: 159 ± 0.58) of IDA wild-type and mutant transcripts in the 35S promoter over-expression lines analyzed in (C). (E) Magnified view of representative abscission zones from 35S::IDA, Col-0 wild-type and 35S::IDA K66A/R67A double-mutant T3 transgenic lines.	FIG
494	497	35S	gene	Up to inflorescence position 4, petal break in 35S::IDA K66A/R67A mutant plants was significantly increased compared to both Col-0 control plants (b) and 35S::IDA plants (c) (D) Normalized expression levels (relative expression ± standard error; ida: -0.02 ± 0.001; Col-0: 1 ± 0.11; 35S::IDA 124 ± 0.75; 35S::IDA K66A/R67A: 159 ± 0.58) of IDA wild-type and mutant transcripts in the 35S promoter over-expression lines analyzed in (C). (E) Magnified view of representative abscission zones from 35S::IDA, Col-0 wild-type and 35S::IDA K66A/R67A double-mutant T3 transgenic lines.	FIG
499	502	IDA	protein	Up to inflorescence position 4, petal break in 35S::IDA K66A/R67A mutant plants was significantly increased compared to both Col-0 control plants (b) and 35S::IDA plants (c) (D) Normalized expression levels (relative expression ± standard error; ida: -0.02 ± 0.001; Col-0: 1 ± 0.11; 35S::IDA 124 ± 0.75; 35S::IDA K66A/R67A: 159 ± 0.58) of IDA wild-type and mutant transcripts in the 35S promoter over-expression lines analyzed in (C). (E) Magnified view of representative abscission zones from 35S::IDA, Col-0 wild-type and 35S::IDA K66A/R67A double-mutant T3 transgenic lines.	FIG
510	519	wild-type	protein_state	Up to inflorescence position 4, petal break in 35S::IDA K66A/R67A mutant plants was significantly increased compared to both Col-0 control plants (b) and 35S::IDA plants (c) (D) Normalized expression levels (relative expression ± standard error; ida: -0.02 ± 0.001; Col-0: 1 ± 0.11; 35S::IDA 124 ± 0.75; 35S::IDA K66A/R67A: 159 ± 0.58) of IDA wild-type and mutant transcripts in the 35S promoter over-expression lines analyzed in (C). (E) Magnified view of representative abscission zones from 35S::IDA, Col-0 wild-type and 35S::IDA K66A/R67A double-mutant T3 transgenic lines.	FIG
524	527	35S	gene	Up to inflorescence position 4, petal break in 35S::IDA K66A/R67A mutant plants was significantly increased compared to both Col-0 control plants (b) and 35S::IDA plants (c) (D) Normalized expression levels (relative expression ± standard error; ida: -0.02 ± 0.001; Col-0: 1 ± 0.11; 35S::IDA 124 ± 0.75; 35S::IDA K66A/R67A: 159 ± 0.58) of IDA wild-type and mutant transcripts in the 35S promoter over-expression lines analyzed in (C). (E) Magnified view of representative abscission zones from 35S::IDA, Col-0 wild-type and 35S::IDA K66A/R67A double-mutant T3 transgenic lines.	FIG
529	542	IDA K66A/R67A	mutant	Up to inflorescence position 4, petal break in 35S::IDA K66A/R67A mutant plants was significantly increased compared to both Col-0 control plants (b) and 35S::IDA plants (c) (D) Normalized expression levels (relative expression ± standard error; ida: -0.02 ± 0.001; Col-0: 1 ± 0.11; 35S::IDA 124 ± 0.75; 35S::IDA K66A/R67A: 159 ± 0.58) of IDA wild-type and mutant transcripts in the 35S promoter over-expression lines analyzed in (C). (E) Magnified view of representative abscission zones from 35S::IDA, Col-0 wild-type and 35S::IDA K66A/R67A double-mutant T3 transgenic lines.	FIG
543	556	double-mutant	protein_state	Up to inflorescence position 4, petal break in 35S::IDA K66A/R67A mutant plants was significantly increased compared to both Col-0 control plants (b) and 35S::IDA plants (c) (D) Normalized expression levels (relative expression ± standard error; ida: -0.02 ± 0.001; Col-0: 1 ± 0.11; 35S::IDA 124 ± 0.75; 35S::IDA K66A/R67A: 159 ± 0.58) of IDA wild-type and mutant transcripts in the 35S promoter over-expression lines analyzed in (C). (E) Magnified view of representative abscission zones from 35S::IDA, Col-0 wild-type and 35S::IDA K66A/R67A double-mutant T3 transgenic lines.	FIG
557	576	T3 transgenic lines	experimental_method	Up to inflorescence position 4, petal break in 35S::IDA K66A/R67A mutant plants was significantly increased compared to both Col-0 control plants (b) and 35S::IDA plants (c) (D) Normalized expression levels (relative expression ± standard error; ida: -0.02 ± 0.001; Col-0: 1 ± 0.11; 35S::IDA 124 ± 0.75; 35S::IDA K66A/R67A: 159 ± 0.58) of IDA wild-type and mutant transcripts in the 35S promoter over-expression lines analyzed in (C). (E) Magnified view of representative abscission zones from 35S::IDA, Col-0 wild-type and 35S::IDA K66A/R67A double-mutant T3 transgenic lines.	FIG
13	16	35S	gene	15 out of 15 35S::IDA plants, 0 out of 15 Col-0 plants and 0 out of 15 35S::IDA K66A/R67A double-mutant plants, showed an enlarged abscission zone, respectively (3 independent lines were analyzed).	FIG
18	21	IDA	protein	15 out of 15 35S::IDA plants, 0 out of 15 Col-0 plants and 0 out of 15 35S::IDA K66A/R67A double-mutant plants, showed an enlarged abscission zone, respectively (3 independent lines were analyzed).	FIG
22	28	plants	taxonomy_domain	15 out of 15 35S::IDA plants, 0 out of 15 Col-0 plants and 0 out of 15 35S::IDA K66A/R67A double-mutant plants, showed an enlarged abscission zone, respectively (3 independent lines were analyzed).	FIG
48	54	plants	taxonomy_domain	15 out of 15 35S::IDA plants, 0 out of 15 Col-0 plants and 0 out of 15 35S::IDA K66A/R67A double-mutant plants, showed an enlarged abscission zone, respectively (3 independent lines were analyzed).	FIG
71	74	35S	gene	15 out of 15 35S::IDA plants, 0 out of 15 Col-0 plants and 0 out of 15 35S::IDA K66A/R67A double-mutant plants, showed an enlarged abscission zone, respectively (3 independent lines were analyzed).	FIG
76	89	IDA K66A/R67A	mutant	15 out of 15 35S::IDA plants, 0 out of 15 Col-0 plants and 0 out of 15 35S::IDA K66A/R67A double-mutant plants, showed an enlarged abscission zone, respectively (3 independent lines were analyzed).	FIG
90	103	double-mutant	protein_state	15 out of 15 35S::IDA plants, 0 out of 15 Col-0 plants and 0 out of 15 35S::IDA K66A/R67A double-mutant plants, showed an enlarged abscission zone, respectively (3 independent lines were analyzed).	FIG
104	110	plants	taxonomy_domain	15 out of 15 35S::IDA plants, 0 out of 15 Col-0 plants and 0 out of 15 35S::IDA K66A/R67A double-mutant plants, showed an enlarged abscission zone, respectively (3 independent lines were analyzed).	FIG
32	35	IDA	protein	The four C-terminal residues in IDA (Lys66IDA-Asn69IDA) are conserved among IDA family members and are in direct contact with SERK1 (Figures 1A, 4C).	RESULTS
37	54	Lys66IDA-Asn69IDA	residue_range	The four C-terminal residues in IDA (Lys66IDA-Asn69IDA) are conserved among IDA family members and are in direct contact with SERK1 (Figures 1A, 4C).	RESULTS
60	69	conserved	protein_state	The four C-terminal residues in IDA (Lys66IDA-Asn69IDA) are conserved among IDA family members and are in direct contact with SERK1 (Figures 1A, 4C).	RESULTS
76	94	IDA family members	protein_type	The four C-terminal residues in IDA (Lys66IDA-Asn69IDA) are conserved among IDA family members and are in direct contact with SERK1 (Figures 1A, 4C).	RESULTS
126	131	SERK1	protein	The four C-terminal residues in IDA (Lys66IDA-Asn69IDA) are conserved among IDA family members and are in direct contact with SERK1 (Figures 1A, 4C).	RESULTS
39	52	HAESA – SERK1	complex_assembly	We thus assessed their contribution to HAESA – SERK1 complex formation.	RESULTS
0	8	Deletion	experimental_method	Deletion of the buried Asn69IDA completely inhibits receptor – co-receptor complex formation and HSL2 activation (Figure 5A,B).	RESULTS
23	28	Asn69	residue_name_number	Deletion of the buried Asn69IDA completely inhibits receptor – co-receptor complex formation and HSL2 activation (Figure 5A,B).	RESULTS
28	31	IDA	protein	Deletion of the buried Asn69IDA completely inhibits receptor – co-receptor complex formation and HSL2 activation (Figure 5A,B).	RESULTS
32	51	completely inhibits	protein_state	Deletion of the buried Asn69IDA completely inhibits receptor – co-receptor complex formation and HSL2 activation (Figure 5A,B).	RESULTS
2	11	synthetic	protein_state	A synthetic Lys66IDA/Arg67IDA → Ala mutant peptide (IDA K66A/R66A) showed a 10 fold reduced binding affinity when titrated in a HAESA/SERK1 protein solution (Figures 5A,B, 2D).	RESULTS
12	35	Lys66IDA/Arg67IDA → Ala	mutant	A synthetic Lys66IDA/Arg67IDA → Ala mutant peptide (IDA K66A/R66A) showed a 10 fold reduced binding affinity when titrated in a HAESA/SERK1 protein solution (Figures 5A,B, 2D).	RESULTS
36	42	mutant	protein_state	A synthetic Lys66IDA/Arg67IDA → Ala mutant peptide (IDA K66A/R66A) showed a 10 fold reduced binding affinity when titrated in a HAESA/SERK1 protein solution (Figures 5A,B, 2D).	RESULTS
43	50	peptide	chemical	A synthetic Lys66IDA/Arg67IDA → Ala mutant peptide (IDA K66A/R66A) showed a 10 fold reduced binding affinity when titrated in a HAESA/SERK1 protein solution (Figures 5A,B, 2D).	RESULTS
52	65	IDA K66A/R66A	mutant	A synthetic Lys66IDA/Arg67IDA → Ala mutant peptide (IDA K66A/R66A) showed a 10 fold reduced binding affinity when titrated in a HAESA/SERK1 protein solution (Figures 5A,B, 2D).	RESULTS
92	108	binding affinity	evidence	A synthetic Lys66IDA/Arg67IDA → Ala mutant peptide (IDA K66A/R66A) showed a 10 fold reduced binding affinity when titrated in a HAESA/SERK1 protein solution (Figures 5A,B, 2D).	RESULTS
114	122	titrated	experimental_method	A synthetic Lys66IDA/Arg67IDA → Ala mutant peptide (IDA K66A/R66A) showed a 10 fold reduced binding affinity when titrated in a HAESA/SERK1 protein solution (Figures 5A,B, 2D).	RESULTS
128	133	HAESA	protein	A synthetic Lys66IDA/Arg67IDA → Ala mutant peptide (IDA K66A/R66A) showed a 10 fold reduced binding affinity when titrated in a HAESA/SERK1 protein solution (Figures 5A,B, 2D).	RESULTS
134	139	SERK1	protein	A synthetic Lys66IDA/Arg67IDA → Ala mutant peptide (IDA K66A/R66A) showed a 10 fold reduced binding affinity when titrated in a HAESA/SERK1 protein solution (Figures 5A,B, 2D).	RESULTS
3	17	over-expressed	experimental_method	We over-expressed full-length wild-type IDA or this Lys66IDA/Arg67IDA → Ala double-mutant to similar levels in Col-0 Arabidopsis plants (Figure 5D).	RESULTS
18	29	full-length	protein_state	We over-expressed full-length wild-type IDA or this Lys66IDA/Arg67IDA → Ala double-mutant to similar levels in Col-0 Arabidopsis plants (Figure 5D).	RESULTS
30	39	wild-type	protein_state	We over-expressed full-length wild-type IDA or this Lys66IDA/Arg67IDA → Ala double-mutant to similar levels in Col-0 Arabidopsis plants (Figure 5D).	RESULTS
40	43	IDA	protein	We over-expressed full-length wild-type IDA or this Lys66IDA/Arg67IDA → Ala double-mutant to similar levels in Col-0 Arabidopsis plants (Figure 5D).	RESULTS
52	75	Lys66IDA/Arg67IDA → Ala	mutant	We over-expressed full-length wild-type IDA or this Lys66IDA/Arg67IDA → Ala double-mutant to similar levels in Col-0 Arabidopsis plants (Figure 5D).	RESULTS
76	89	double-mutant	protein_state	We over-expressed full-length wild-type IDA or this Lys66IDA/Arg67IDA → Ala double-mutant to similar levels in Col-0 Arabidopsis plants (Figure 5D).	RESULTS
117	128	Arabidopsis	taxonomy_domain	We over-expressed full-length wild-type IDA or this Lys66IDA/Arg67IDA → Ala double-mutant to similar levels in Col-0 Arabidopsis plants (Figure 5D).	RESULTS
129	135	plants	taxonomy_domain	We over-expressed full-length wild-type IDA or this Lys66IDA/Arg67IDA → Ala double-mutant to similar levels in Col-0 Arabidopsis plants (Figure 5D).	RESULTS
14	29	over-expression	experimental_method	We found that over-expression of wild-type IDA leads to early floral abscission and an enlargement of the abscission zone (Figure 5C–E).	RESULTS
33	42	wild-type	protein_state	We found that over-expression of wild-type IDA leads to early floral abscission and an enlargement of the abscission zone (Figure 5C–E).	RESULTS
43	46	IDA	protein	We found that over-expression of wild-type IDA leads to early floral abscission and an enlargement of the abscission zone (Figure 5C–E).	RESULTS
13	28	over-expression	experimental_method	In contrast, over-expression of the IDA Lys66IDA/Arg67IDA → Ala double mutant significantly delays floral abscission when compared to wild-type control plants, suggesting that the mutant IDA peptide has reduced activity in planta (Figure 5C–E).	RESULTS
36	63	IDA Lys66IDA/Arg67IDA → Ala	mutant	In contrast, over-expression of the IDA Lys66IDA/Arg67IDA → Ala double mutant significantly delays floral abscission when compared to wild-type control plants, suggesting that the mutant IDA peptide has reduced activity in planta (Figure 5C–E).	RESULTS
64	77	double mutant	protein_state	In contrast, over-expression of the IDA Lys66IDA/Arg67IDA → Ala double mutant significantly delays floral abscission when compared to wild-type control plants, suggesting that the mutant IDA peptide has reduced activity in planta (Figure 5C–E).	RESULTS
134	143	wild-type	protein_state	In contrast, over-expression of the IDA Lys66IDA/Arg67IDA → Ala double mutant significantly delays floral abscission when compared to wild-type control plants, suggesting that the mutant IDA peptide has reduced activity in planta (Figure 5C–E).	RESULTS
152	158	plants	taxonomy_domain	In contrast, over-expression of the IDA Lys66IDA/Arg67IDA → Ala double mutant significantly delays floral abscission when compared to wild-type control plants, suggesting that the mutant IDA peptide has reduced activity in planta (Figure 5C–E).	RESULTS
180	186	mutant	protein_state	In contrast, over-expression of the IDA Lys66IDA/Arg67IDA → Ala double mutant significantly delays floral abscission when compared to wild-type control plants, suggesting that the mutant IDA peptide has reduced activity in planta (Figure 5C–E).	RESULTS
187	198	IDA peptide	chemical	In contrast, over-expression of the IDA Lys66IDA/Arg67IDA → Ala double mutant significantly delays floral abscission when compared to wild-type control plants, suggesting that the mutant IDA peptide has reduced activity in planta (Figure 5C–E).	RESULTS
223	229	planta	taxonomy_domain	In contrast, over-expression of the IDA Lys66IDA/Arg67IDA → Ala double mutant significantly delays floral abscission when compared to wild-type control plants, suggesting that the mutant IDA peptide has reduced activity in planta (Figure 5C–E).	RESULTS
14	17	35S	gene	Comparison of 35S::IDA wild-type and mutant plants further indicates that mutation of Lys66IDA/Arg67IDA → Ala may cause a weak dominant negative effect (Figure 5C–E).	RESULTS
19	22	IDA	protein	Comparison of 35S::IDA wild-type and mutant plants further indicates that mutation of Lys66IDA/Arg67IDA → Ala may cause a weak dominant negative effect (Figure 5C–E).	RESULTS
23	32	wild-type	protein_state	Comparison of 35S::IDA wild-type and mutant plants further indicates that mutation of Lys66IDA/Arg67IDA → Ala may cause a weak dominant negative effect (Figure 5C–E).	RESULTS
37	43	mutant	protein_state	Comparison of 35S::IDA wild-type and mutant plants further indicates that mutation of Lys66IDA/Arg67IDA → Ala may cause a weak dominant negative effect (Figure 5C–E).	RESULTS
44	50	plants	taxonomy_domain	Comparison of 35S::IDA wild-type and mutant plants further indicates that mutation of Lys66IDA/Arg67IDA → Ala may cause a weak dominant negative effect (Figure 5C–E).	RESULTS
74	82	mutation	experimental_method	Comparison of 35S::IDA wild-type and mutant plants further indicates that mutation of Lys66IDA/Arg67IDA → Ala may cause a weak dominant negative effect (Figure 5C–E).	RESULTS
86	109	Lys66IDA/Arg67IDA → Ala	mutant	Comparison of 35S::IDA wild-type and mutant plants further indicates that mutation of Lys66IDA/Arg67IDA → Ala may cause a weak dominant negative effect (Figure 5C–E).	RESULTS
22	32	structures	evidence	In agreement with our structures and biochemical assays, this experiment suggests a role of the conserved IDA C-terminus in the control of floral abscission.	RESULTS
37	55	biochemical assays	experimental_method	In agreement with our structures and biochemical assays, this experiment suggests a role of the conserved IDA C-terminus in the control of floral abscission.	RESULTS
96	105	conserved	protein_state	In agreement with our structures and biochemical assays, this experiment suggests a role of the conserved IDA C-terminus in the control of floral abscission.	RESULTS
106	109	IDA	protein	In agreement with our structures and biochemical assays, this experiment suggests a role of the conserved IDA C-terminus in the control of floral abscission.	RESULTS
15	21	animal	taxonomy_domain	In contrast to animal LRR receptors, plant LRR-RKs harbor spiral-shaped ectodomains and thus they require shape-complementary co-receptor proteins for receptor activation.	DISCUSS
22	35	LRR receptors	protein_type	In contrast to animal LRR receptors, plant LRR-RKs harbor spiral-shaped ectodomains and thus they require shape-complementary co-receptor proteins for receptor activation.	DISCUSS
37	42	plant	taxonomy_domain	In contrast to animal LRR receptors, plant LRR-RKs harbor spiral-shaped ectodomains and thus they require shape-complementary co-receptor proteins for receptor activation.	DISCUSS
43	50	LRR-RKs	structure_element	In contrast to animal LRR receptors, plant LRR-RKs harbor spiral-shaped ectodomains and thus they require shape-complementary co-receptor proteins for receptor activation.	DISCUSS
58	71	spiral-shaped	protein_state	In contrast to animal LRR receptors, plant LRR-RKs harbor spiral-shaped ectodomains and thus they require shape-complementary co-receptor proteins for receptor activation.	DISCUSS
72	83	ectodomains	structure_element	In contrast to animal LRR receptors, plant LRR-RKs harbor spiral-shaped ectodomains and thus they require shape-complementary co-receptor proteins for receptor activation.	DISCUSS
106	125	shape-complementary	protein_state	In contrast to animal LRR receptors, plant LRR-RKs harbor spiral-shaped ectodomains and thus they require shape-complementary co-receptor proteins for receptor activation.	DISCUSS
126	146	co-receptor proteins	protein_type	In contrast to animal LRR receptors, plant LRR-RKs harbor spiral-shaped ectodomains and thus they require shape-complementary co-receptor proteins for receptor activation.	DISCUSS
32	37	plant	taxonomy_domain	For a rapidly growing number of plant signaling pathways, SERK proteins act as these essential co-receptors (; ).	DISCUSS
58	71	SERK proteins	protein_type	For a rapidly growing number of plant signaling pathways, SERK proteins act as these essential co-receptors (; ).	DISCUSS
95	107	co-receptors	protein_type	For a rapidly growing number of plant signaling pathways, SERK proteins act as these essential co-receptors (; ).	DISCUSS
63	68	plant	taxonomy_domain	 SERK1 has been previously reported as a positive regulator in plant embryogenesis, male sporogenesis, brassinosteroid signaling and in phytosulfokine perception.	DISCUSS
84	89	SERK1	protein	Recent findings by and our mechanistic studies now also support a positive role for SERK1 in floral abscission.	DISCUSS
3	10	serk1-1	gene	As serk1-1 mutant plants show intermediate abscission phenotypes when compared to haesa/hsl2 mutants, SERK1 likely acts redundantly with other SERKs in the abscission zone (Figure 3A).	DISCUSS
11	17	mutant	protein_state	As serk1-1 mutant plants show intermediate abscission phenotypes when compared to haesa/hsl2 mutants, SERK1 likely acts redundantly with other SERKs in the abscission zone (Figure 3A).	DISCUSS
18	24	plants	taxonomy_domain	As serk1-1 mutant plants show intermediate abscission phenotypes when compared to haesa/hsl2 mutants, SERK1 likely acts redundantly with other SERKs in the abscission zone (Figure 3A).	DISCUSS
82	87	haesa	gene	As serk1-1 mutant plants show intermediate abscission phenotypes when compared to haesa/hsl2 mutants, SERK1 likely acts redundantly with other SERKs in the abscission zone (Figure 3A).	DISCUSS
93	100	mutants	protein_state	As serk1-1 mutant plants show intermediate abscission phenotypes when compared to haesa/hsl2 mutants, SERK1 likely acts redundantly with other SERKs in the abscission zone (Figure 3A).	DISCUSS
102	107	SERK1	protein	As serk1-1 mutant plants show intermediate abscission phenotypes when compared to haesa/hsl2 mutants, SERK1 likely acts redundantly with other SERKs in the abscission zone (Figure 3A).	DISCUSS
143	148	SERKs	protein_type	As serk1-1 mutant plants show intermediate abscission phenotypes when compared to haesa/hsl2 mutants, SERK1 likely acts redundantly with other SERKs in the abscission zone (Figure 3A).	DISCUSS
38	43	SERK1	protein	It has been previously suggested that SERK1 can inhibit cell separation.	DISCUSS
30	35	SERK1	protein	However our results show that SERK1 also can activate this process upon IDA sensing, indicating that SERKs may fulfill several different functions in the course of the abscission process.	DISCUSS
72	75	IDA	protein	However our results show that SERK1 also can activate this process upon IDA sensing, indicating that SERKs may fulfill several different functions in the course of the abscission process.	DISCUSS
101	106	SERKs	protein_type	However our results show that SERK1 also can activate this process upon IDA sensing, indicating that SERKs may fulfill several different functions in the course of the abscission process.	DISCUSS
26	32	mature	protein_state	While the sequence of the mature IDA peptide has not been experimentally determined in planta, our HAESA-IDA complex structures and calorimetry assays suggest that active IDLs are hydroxyprolinated dodecamers.	DISCUSS
33	44	IDA peptide	chemical	While the sequence of the mature IDA peptide has not been experimentally determined in planta, our HAESA-IDA complex structures and calorimetry assays suggest that active IDLs are hydroxyprolinated dodecamers.	DISCUSS
87	93	planta	taxonomy_domain	While the sequence of the mature IDA peptide has not been experimentally determined in planta, our HAESA-IDA complex structures and calorimetry assays suggest that active IDLs are hydroxyprolinated dodecamers.	DISCUSS
99	108	HAESA-IDA	complex_assembly	While the sequence of the mature IDA peptide has not been experimentally determined in planta, our HAESA-IDA complex structures and calorimetry assays suggest that active IDLs are hydroxyprolinated dodecamers.	DISCUSS
117	127	structures	evidence	While the sequence of the mature IDA peptide has not been experimentally determined in planta, our HAESA-IDA complex structures and calorimetry assays suggest that active IDLs are hydroxyprolinated dodecamers.	DISCUSS
132	150	calorimetry assays	evidence	While the sequence of the mature IDA peptide has not been experimentally determined in planta, our HAESA-IDA complex structures and calorimetry assays suggest that active IDLs are hydroxyprolinated dodecamers.	DISCUSS
164	170	active	protein_state	While the sequence of the mature IDA peptide has not been experimentally determined in planta, our HAESA-IDA complex structures and calorimetry assays suggest that active IDLs are hydroxyprolinated dodecamers.	DISCUSS
171	175	IDLs	protein_type	While the sequence of the mature IDA peptide has not been experimentally determined in planta, our HAESA-IDA complex structures and calorimetry assays suggest that active IDLs are hydroxyprolinated dodecamers.	DISCUSS
180	197	hydroxyprolinated	protein_state	While the sequence of the mature IDA peptide has not been experimentally determined in planta, our HAESA-IDA complex structures and calorimetry assays suggest that active IDLs are hydroxyprolinated dodecamers.	DISCUSS
198	208	dodecamers	structure_element	While the sequence of the mature IDA peptide has not been experimentally determined in planta, our HAESA-IDA complex structures and calorimetry assays suggest that active IDLs are hydroxyprolinated dodecamers.	DISCUSS
64	75	full-length	protein_state	It will be thus interesting to see if proteolytic processing of full-length IDA in vivo is regulated in a cell-type or tissue-specific manner.	DISCUSS
76	79	IDA	protein	It will be thus interesting to see if proteolytic processing of full-length IDA in vivo is regulated in a cell-type or tissue-specific manner.	DISCUSS
12	15	Hyp	residue_name	The central Hyp residue in IDA is found buried in the HAESA peptide binding surface and thus this post-translational modification may regulate IDA bioactivity.	DISCUSS
27	30	IDA	protein	The central Hyp residue in IDA is found buried in the HAESA peptide binding surface and thus this post-translational modification may regulate IDA bioactivity.	DISCUSS
54	59	HAESA	protein	The central Hyp residue in IDA is found buried in the HAESA peptide binding surface and thus this post-translational modification may regulate IDA bioactivity.	DISCUSS
60	83	peptide binding surface	site	The central Hyp residue in IDA is found buried in the HAESA peptide binding surface and thus this post-translational modification may regulate IDA bioactivity.	DISCUSS
143	146	IDA	protein	The central Hyp residue in IDA is found buried in the HAESA peptide binding surface and thus this post-translational modification may regulate IDA bioactivity.	DISCUSS
4	51	comparative structural and biochemical analysis	experimental_method	Our comparative structural and biochemical analysis further suggests that IDLs share a common receptor binding mode, but may preferably bind to HAESA, HSL1 or HSL2 in different plant tissues and organs.	DISCUSS
74	78	IDLs	protein_type	Our comparative structural and biochemical analysis further suggests that IDLs share a common receptor binding mode, but may preferably bind to HAESA, HSL1 or HSL2 in different plant tissues and organs.	DISCUSS
144	149	HAESA	protein	Our comparative structural and biochemical analysis further suggests that IDLs share a common receptor binding mode, but may preferably bind to HAESA, HSL1 or HSL2 in different plant tissues and organs.	DISCUSS
151	155	HSL1	protein	Our comparative structural and biochemical analysis further suggests that IDLs share a common receptor binding mode, but may preferably bind to HAESA, HSL1 or HSL2 in different plant tissues and organs.	DISCUSS
159	163	HSL2	protein	Our comparative structural and biochemical analysis further suggests that IDLs share a common receptor binding mode, but may preferably bind to HAESA, HSL1 or HSL2 in different plant tissues and organs.	DISCUSS
177	182	plant	taxonomy_domain	Our comparative structural and biochemical analysis further suggests that IDLs share a common receptor binding mode, but may preferably bind to HAESA, HSL1 or HSL2 in different plant tissues and organs.	DISCUSS
7	38	quantitative biochemical assays	experimental_method	In our quantitative biochemical assays, the presence of SERK1 dramatically increases the HAESA binding specificity and affinity for IDA.	DISCUSS
44	55	presence of	protein_state	In our quantitative biochemical assays, the presence of SERK1 dramatically increases the HAESA binding specificity and affinity for IDA.	DISCUSS
56	61	SERK1	protein	In our quantitative biochemical assays, the presence of SERK1 dramatically increases the HAESA binding specificity and affinity for IDA.	DISCUSS
89	94	HAESA	protein	In our quantitative biochemical assays, the presence of SERK1 dramatically increases the HAESA binding specificity and affinity for IDA.	DISCUSS
132	135	IDA	protein	In our quantitative biochemical assays, the presence of SERK1 dramatically increases the HAESA binding specificity and affinity for IDA.	DISCUSS
48	57	structure	evidence	This observation is consistent with our complex structure in which receptor and co-receptor together form the IDA binding pocket.	DISCUSS
110	128	IDA binding pocket	site	This observation is consistent with our complex structure in which receptor and co-receptor together form the IDA binding pocket.	DISCUSS
14	19	SERK1	protein	The fact that SERK1 specifically interacts with the very C-terminus of IDLs may allow for the rational design of peptide hormone antagonists, as previously demonstrated for the brassinosteroid pathway.	DISCUSS
71	75	IDLs	protein_type	The fact that SERK1 specifically interacts with the very C-terminus of IDLs may allow for the rational design of peptide hormone antagonists, as previously demonstrated for the brassinosteroid pathway.	DISCUSS
113	140	peptide hormone antagonists	chemical	The fact that SERK1 specifically interacts with the very C-terminus of IDLs may allow for the rational design of peptide hormone antagonists, as previously demonstrated for the brassinosteroid pathway.	DISCUSS
17	35	calorimetry assays	experimental_method	Importantly, our calorimetry assays reveal that the SERK1 ectodomain binds HAESA with nanomolar affinity, but only in the presence of IDA (Figure 3C).	DISCUSS
52	57	SERK1	protein	Importantly, our calorimetry assays reveal that the SERK1 ectodomain binds HAESA with nanomolar affinity, but only in the presence of IDA (Figure 3C).	DISCUSS
58	68	ectodomain	structure_element	Importantly, our calorimetry assays reveal that the SERK1 ectodomain binds HAESA with nanomolar affinity, but only in the presence of IDA (Figure 3C).	DISCUSS
69	74	binds	protein_state	Importantly, our calorimetry assays reveal that the SERK1 ectodomain binds HAESA with nanomolar affinity, but only in the presence of IDA (Figure 3C).	DISCUSS
75	80	HAESA	protein	Importantly, our calorimetry assays reveal that the SERK1 ectodomain binds HAESA with nanomolar affinity, but only in the presence of IDA (Figure 3C).	DISCUSS
122	133	presence of	protein_state	Importantly, our calorimetry assays reveal that the SERK1 ectodomain binds HAESA with nanomolar affinity, but only in the presence of IDA (Figure 3C).	DISCUSS
134	137	IDA	protein	Importantly, our calorimetry assays reveal that the SERK1 ectodomain binds HAESA with nanomolar affinity, but only in the presence of IDA (Figure 3C).	DISCUSS
80	85	HAESA	protein	This ligand-induced formation of a receptor – co-receptor complex may allow the HAESA and SERK1 kinase domains to efficiently trans-phosphorylate and activate each other in the cytoplasm.	DISCUSS
90	95	SERK1	protein	This ligand-induced formation of a receptor – co-receptor complex may allow the HAESA and SERK1 kinase domains to efficiently trans-phosphorylate and activate each other in the cytoplasm.	DISCUSS
96	110	kinase domains	structure_element	This ligand-induced formation of a receptor – co-receptor complex may allow the HAESA and SERK1 kinase domains to efficiently trans-phosphorylate and activate each other in the cytoplasm.	DISCUSS
32	50	binding affinities	evidence	It is of note that our reported binding affinities for IDA and SERK1 have been measured using synthetic peptides and the isolated HAESA and SERK1 ectodomains, and thus might differ in the context of the full-length, membrane-embedded signaling complex.	DISCUSS
55	58	IDA	protein	It is of note that our reported binding affinities for IDA and SERK1 have been measured using synthetic peptides and the isolated HAESA and SERK1 ectodomains, and thus might differ in the context of the full-length, membrane-embedded signaling complex.	DISCUSS
63	68	SERK1	protein	It is of note that our reported binding affinities for IDA and SERK1 have been measured using synthetic peptides and the isolated HAESA and SERK1 ectodomains, and thus might differ in the context of the full-length, membrane-embedded signaling complex.	DISCUSS
94	103	synthetic	protein_state	It is of note that our reported binding affinities for IDA and SERK1 have been measured using synthetic peptides and the isolated HAESA and SERK1 ectodomains, and thus might differ in the context of the full-length, membrane-embedded signaling complex.	DISCUSS
104	112	peptides	chemical	It is of note that our reported binding affinities for IDA and SERK1 have been measured using synthetic peptides and the isolated HAESA and SERK1 ectodomains, and thus might differ in the context of the full-length, membrane-embedded signaling complex.	DISCUSS
121	129	isolated	experimental_method	It is of note that our reported binding affinities for IDA and SERK1 have been measured using synthetic peptides and the isolated HAESA and SERK1 ectodomains, and thus might differ in the context of the full-length, membrane-embedded signaling complex.	DISCUSS
130	135	HAESA	protein	It is of note that our reported binding affinities for IDA and SERK1 have been measured using synthetic peptides and the isolated HAESA and SERK1 ectodomains, and thus might differ in the context of the full-length, membrane-embedded signaling complex.	DISCUSS
140	145	SERK1	protein	It is of note that our reported binding affinities for IDA and SERK1 have been measured using synthetic peptides and the isolated HAESA and SERK1 ectodomains, and thus might differ in the context of the full-length, membrane-embedded signaling complex.	DISCUSS
146	157	ectodomains	structure_element	It is of note that our reported binding affinities for IDA and SERK1 have been measured using synthetic peptides and the isolated HAESA and SERK1 ectodomains, and thus might differ in the context of the full-length, membrane-embedded signaling complex.	DISCUSS
203	214	full-length	protein_state	It is of note that our reported binding affinities for IDA and SERK1 have been measured using synthetic peptides and the isolated HAESA and SERK1 ectodomains, and thus might differ in the context of the full-length, membrane-embedded signaling complex.	DISCUSS
216	233	membrane-embedded	protein_state	It is of note that our reported binding affinities for IDA and SERK1 have been measured using synthetic peptides and the isolated HAESA and SERK1 ectodomains, and thus might differ in the context of the full-length, membrane-embedded signaling complex.	DISCUSS
0	5	SERK1	protein	SERK1 uses partially overlapping surface areas to activate different plant signaling receptors.	FIG
69	74	plant	taxonomy_domain	SERK1 uses partially overlapping surface areas to activate different plant signaling receptors.	FIG
75	94	signaling receptors	protein_type	SERK1 uses partially overlapping surface areas to activate different plant signaling receptors.	FIG
4	25	Structural comparison	experimental_method	(A) Structural comparison of plant steroid and peptide hormone membrane signaling complexes.	FIG
29	34	plant	taxonomy_domain	(A) Structural comparison of plant steroid and peptide hormone membrane signaling complexes.	FIG
35	42	steroid	chemical	(A) Structural comparison of plant steroid and peptide hormone membrane signaling complexes.	FIG
47	62	peptide hormone	protein_type	(A) Structural comparison of plant steroid and peptide hormone membrane signaling complexes.	FIG
63	91	membrane signaling complexes	protein_type	(A) Structural comparison of plant steroid and peptide hormone membrane signaling complexes.	FIG
30	35	HAESA	protein	Left panel: Ribbon diagram of HAESA (in blue), SERK1 (in orange) and IDA (in bonds and surface represention).	FIG
47	52	SERK1	protein	Left panel: Ribbon diagram of HAESA (in blue), SERK1 (in orange) and IDA (in bonds and surface represention).	FIG
69	72	IDA	protein	Left panel: Ribbon diagram of HAESA (in blue), SERK1 (in orange) and IDA (in bonds and surface represention).	FIG
35	40	plant	taxonomy_domain	Right panel: Ribbon diagram of the plant steroid receptor BRI1 (in blue) bound to brassinolide (in gray, in bonds representation) and to SERK1, shown in the same orientation (PDB-ID. 4lsx).	FIG
41	57	steroid receptor	protein_type	Right panel: Ribbon diagram of the plant steroid receptor BRI1 (in blue) bound to brassinolide (in gray, in bonds representation) and to SERK1, shown in the same orientation (PDB-ID. 4lsx).	FIG
58	62	BRI1	protein	Right panel: Ribbon diagram of the plant steroid receptor BRI1 (in blue) bound to brassinolide (in gray, in bonds representation) and to SERK1, shown in the same orientation (PDB-ID. 4lsx).	FIG
73	81	bound to	protein_state	Right panel: Ribbon diagram of the plant steroid receptor BRI1 (in blue) bound to brassinolide (in gray, in bonds representation) and to SERK1, shown in the same orientation (PDB-ID. 4lsx).	FIG
82	94	brassinolide	chemical	Right panel: Ribbon diagram of the plant steroid receptor BRI1 (in blue) bound to brassinolide (in gray, in bonds representation) and to SERK1, shown in the same orientation (PDB-ID. 4lsx).	FIG
137	142	SERK1	protein	Right panel: Ribbon diagram of the plant steroid receptor BRI1 (in blue) bound to brassinolide (in gray, in bonds representation) and to SERK1, shown in the same orientation (PDB-ID. 4lsx).	FIG
37	42	SERK1	protein	(B) View of the inner surface of the SERK1 LRR domain (PDB-ID 4lsc, surface representation, in gray).	FIG
43	53	LRR domain	structure_element	(B) View of the inner surface of the SERK1 LRR domain (PDB-ID 4lsc, surface representation, in gray).	FIG
20	25	SERK1	protein	A ribbon diagram of SERK1 in the same orientation is shown alongside.	FIG
30	35	HAESA	protein	Residues interacting with the HAESA or BRI1 LRR domains are shown in orange or magenta, respectively.	FIG
39	43	BRI1	protein	Residues interacting with the HAESA or BRI1 LRR domains are shown in orange or magenta, respectively.	FIG
44	55	LRR domains	structure_element	Residues interacting with the HAESA or BRI1 LRR domains are shown in orange or magenta, respectively.	FIG
0	10	Comparison	experimental_method	Comparison of our HAESA – IDA – SERK1 structure with the brassinosteroid receptor signaling complex, where SERK1 also acts as co-receptor, reveals an overall conserved mode of SERK1 binding, while the ligand binding pockets map to very different areas in the corresponding receptors (LRRs 2 – 14; HAESA; LRRs 21 – 25, BRI1) and may involve an island domain (BRI1) or not (HAESA) (Figure 6A).	DISCUSS
18	37	HAESA – IDA – SERK1	complex_assembly	Comparison of our HAESA – IDA – SERK1 structure with the brassinosteroid receptor signaling complex, where SERK1 also acts as co-receptor, reveals an overall conserved mode of SERK1 binding, while the ligand binding pockets map to very different areas in the corresponding receptors (LRRs 2 – 14; HAESA; LRRs 21 – 25, BRI1) and may involve an island domain (BRI1) or not (HAESA) (Figure 6A).	DISCUSS
38	47	structure	evidence	Comparison of our HAESA – IDA – SERK1 structure with the brassinosteroid receptor signaling complex, where SERK1 also acts as co-receptor, reveals an overall conserved mode of SERK1 binding, while the ligand binding pockets map to very different areas in the corresponding receptors (LRRs 2 – 14; HAESA; LRRs 21 – 25, BRI1) and may involve an island domain (BRI1) or not (HAESA) (Figure 6A).	DISCUSS
107	112	SERK1	protein	Comparison of our HAESA – IDA – SERK1 structure with the brassinosteroid receptor signaling complex, where SERK1 also acts as co-receptor, reveals an overall conserved mode of SERK1 binding, while the ligand binding pockets map to very different areas in the corresponding receptors (LRRs 2 – 14; HAESA; LRRs 21 – 25, BRI1) and may involve an island domain (BRI1) or not (HAESA) (Figure 6A).	DISCUSS
126	137	co-receptor	protein_type	Comparison of our HAESA – IDA – SERK1 structure with the brassinosteroid receptor signaling complex, where SERK1 also acts as co-receptor, reveals an overall conserved mode of SERK1 binding, while the ligand binding pockets map to very different areas in the corresponding receptors (LRRs 2 – 14; HAESA; LRRs 21 – 25, BRI1) and may involve an island domain (BRI1) or not (HAESA) (Figure 6A).	DISCUSS
158	167	conserved	protein_state	Comparison of our HAESA – IDA – SERK1 structure with the brassinosteroid receptor signaling complex, where SERK1 also acts as co-receptor, reveals an overall conserved mode of SERK1 binding, while the ligand binding pockets map to very different areas in the corresponding receptors (LRRs 2 – 14; HAESA; LRRs 21 – 25, BRI1) and may involve an island domain (BRI1) or not (HAESA) (Figure 6A).	DISCUSS
176	181	SERK1	protein	Comparison of our HAESA – IDA – SERK1 structure with the brassinosteroid receptor signaling complex, where SERK1 also acts as co-receptor, reveals an overall conserved mode of SERK1 binding, while the ligand binding pockets map to very different areas in the corresponding receptors (LRRs 2 – 14; HAESA; LRRs 21 – 25, BRI1) and may involve an island domain (BRI1) or not (HAESA) (Figure 6A).	DISCUSS
201	223	ligand binding pockets	site	Comparison of our HAESA – IDA – SERK1 structure with the brassinosteroid receptor signaling complex, where SERK1 also acts as co-receptor, reveals an overall conserved mode of SERK1 binding, while the ligand binding pockets map to very different areas in the corresponding receptors (LRRs 2 – 14; HAESA; LRRs 21 – 25, BRI1) and may involve an island domain (BRI1) or not (HAESA) (Figure 6A).	DISCUSS
284	295	LRRs 2 – 14	structure_element	Comparison of our HAESA – IDA – SERK1 structure with the brassinosteroid receptor signaling complex, where SERK1 also acts as co-receptor, reveals an overall conserved mode of SERK1 binding, while the ligand binding pockets map to very different areas in the corresponding receptors (LRRs 2 – 14; HAESA; LRRs 21 – 25, BRI1) and may involve an island domain (BRI1) or not (HAESA) (Figure 6A).	DISCUSS
297	302	HAESA	protein	Comparison of our HAESA – IDA – SERK1 structure with the brassinosteroid receptor signaling complex, where SERK1 also acts as co-receptor, reveals an overall conserved mode of SERK1 binding, while the ligand binding pockets map to very different areas in the corresponding receptors (LRRs 2 – 14; HAESA; LRRs 21 – 25, BRI1) and may involve an island domain (BRI1) or not (HAESA) (Figure 6A).	DISCUSS
304	316	LRRs 21 – 25	structure_element	Comparison of our HAESA – IDA – SERK1 structure with the brassinosteroid receptor signaling complex, where SERK1 also acts as co-receptor, reveals an overall conserved mode of SERK1 binding, while the ligand binding pockets map to very different areas in the corresponding receptors (LRRs 2 – 14; HAESA; LRRs 21 – 25, BRI1) and may involve an island domain (BRI1) or not (HAESA) (Figure 6A).	DISCUSS
318	322	BRI1	protein	Comparison of our HAESA – IDA – SERK1 structure with the brassinosteroid receptor signaling complex, where SERK1 also acts as co-receptor, reveals an overall conserved mode of SERK1 binding, while the ligand binding pockets map to very different areas in the corresponding receptors (LRRs 2 – 14; HAESA; LRRs 21 – 25, BRI1) and may involve an island domain (BRI1) or not (HAESA) (Figure 6A).	DISCUSS
358	362	BRI1	protein	Comparison of our HAESA – IDA – SERK1 structure with the brassinosteroid receptor signaling complex, where SERK1 also acts as co-receptor, reveals an overall conserved mode of SERK1 binding, while the ligand binding pockets map to very different areas in the corresponding receptors (LRRs 2 – 14; HAESA; LRRs 21 – 25, BRI1) and may involve an island domain (BRI1) or not (HAESA) (Figure 6A).	DISCUSS
372	377	HAESA	protein	Comparison of our HAESA – IDA – SERK1 structure with the brassinosteroid receptor signaling complex, where SERK1 also acts as co-receptor, reveals an overall conserved mode of SERK1 binding, while the ligand binding pockets map to very different areas in the corresponding receptors (LRRs 2 – 14; HAESA; LRRs 21 – 25, BRI1) and may involve an island domain (BRI1) or not (HAESA) (Figure 6A).	DISCUSS
24	29	SERK1	protein	Several residues in the SERK1 N-terminal capping domain (Thr59SERK1, Phe61SERK1) and the LRR inner surface (Asp75SERK1, Tyr101SERK1, SER121SERK1, Phe145SERK1) contribute to the formation of both complexes (Figures 4C,D, 6B).	DISCUSS
41	55	capping domain	structure_element	Several residues in the SERK1 N-terminal capping domain (Thr59SERK1, Phe61SERK1) and the LRR inner surface (Asp75SERK1, Tyr101SERK1, SER121SERK1, Phe145SERK1) contribute to the formation of both complexes (Figures 4C,D, 6B).	DISCUSS
57	62	Thr59	residue_name_number	Several residues in the SERK1 N-terminal capping domain (Thr59SERK1, Phe61SERK1) and the LRR inner surface (Asp75SERK1, Tyr101SERK1, SER121SERK1, Phe145SERK1) contribute to the formation of both complexes (Figures 4C,D, 6B).	DISCUSS
62	67	SERK1	protein	Several residues in the SERK1 N-terminal capping domain (Thr59SERK1, Phe61SERK1) and the LRR inner surface (Asp75SERK1, Tyr101SERK1, SER121SERK1, Phe145SERK1) contribute to the formation of both complexes (Figures 4C,D, 6B).	DISCUSS
69	74	Phe61	residue_name_number	Several residues in the SERK1 N-terminal capping domain (Thr59SERK1, Phe61SERK1) and the LRR inner surface (Asp75SERK1, Tyr101SERK1, SER121SERK1, Phe145SERK1) contribute to the formation of both complexes (Figures 4C,D, 6B).	DISCUSS
74	79	SERK1	protein	Several residues in the SERK1 N-terminal capping domain (Thr59SERK1, Phe61SERK1) and the LRR inner surface (Asp75SERK1, Tyr101SERK1, SER121SERK1, Phe145SERK1) contribute to the formation of both complexes (Figures 4C,D, 6B).	DISCUSS
89	106	LRR inner surface	site	Several residues in the SERK1 N-terminal capping domain (Thr59SERK1, Phe61SERK1) and the LRR inner surface (Asp75SERK1, Tyr101SERK1, SER121SERK1, Phe145SERK1) contribute to the formation of both complexes (Figures 4C,D, 6B).	DISCUSS
108	113	Asp75	residue_name_number	Several residues in the SERK1 N-terminal capping domain (Thr59SERK1, Phe61SERK1) and the LRR inner surface (Asp75SERK1, Tyr101SERK1, SER121SERK1, Phe145SERK1) contribute to the formation of both complexes (Figures 4C,D, 6B).	DISCUSS
113	118	SERK1	protein	Several residues in the SERK1 N-terminal capping domain (Thr59SERK1, Phe61SERK1) and the LRR inner surface (Asp75SERK1, Tyr101SERK1, SER121SERK1, Phe145SERK1) contribute to the formation of both complexes (Figures 4C,D, 6B).	DISCUSS
120	126	Tyr101	residue_name_number	Several residues in the SERK1 N-terminal capping domain (Thr59SERK1, Phe61SERK1) and the LRR inner surface (Asp75SERK1, Tyr101SERK1, SER121SERK1, Phe145SERK1) contribute to the formation of both complexes (Figures 4C,D, 6B).	DISCUSS
126	131	SERK1	protein	Several residues in the SERK1 N-terminal capping domain (Thr59SERK1, Phe61SERK1) and the LRR inner surface (Asp75SERK1, Tyr101SERK1, SER121SERK1, Phe145SERK1) contribute to the formation of both complexes (Figures 4C,D, 6B).	DISCUSS
133	139	SER121	residue_name_number	Several residues in the SERK1 N-terminal capping domain (Thr59SERK1, Phe61SERK1) and the LRR inner surface (Asp75SERK1, Tyr101SERK1, SER121SERK1, Phe145SERK1) contribute to the formation of both complexes (Figures 4C,D, 6B).	DISCUSS
139	144	SERK1	protein	Several residues in the SERK1 N-terminal capping domain (Thr59SERK1, Phe61SERK1) and the LRR inner surface (Asp75SERK1, Tyr101SERK1, SER121SERK1, Phe145SERK1) contribute to the formation of both complexes (Figures 4C,D, 6B).	DISCUSS
146	152	Phe145	residue_name_number	Several residues in the SERK1 N-terminal capping domain (Thr59SERK1, Phe61SERK1) and the LRR inner surface (Asp75SERK1, Tyr101SERK1, SER121SERK1, Phe145SERK1) contribute to the formation of both complexes (Figures 4C,D, 6B).	DISCUSS
152	157	SERK1	protein	Several residues in the SERK1 N-terminal capping domain (Thr59SERK1, Phe61SERK1) and the LRR inner surface (Asp75SERK1, Tyr101SERK1, SER121SERK1, Phe145SERK1) contribute to the formation of both complexes (Figures 4C,D, 6B).	DISCUSS
22	27	53-55	residue_range	In addition, residues 53-55SERK1 from the SERK1 N-terminal cap mediate specific interactions with the IDA peptide (Figures 4C, 6B).	DISCUSS
27	32	SERK1	protein	In addition, residues 53-55SERK1 from the SERK1 N-terminal cap mediate specific interactions with the IDA peptide (Figures 4C, 6B).	DISCUSS
42	47	SERK1	protein	In addition, residues 53-55SERK1 from the SERK1 N-terminal cap mediate specific interactions with the IDA peptide (Figures 4C, 6B).	DISCUSS
59	62	cap	structure_element	In addition, residues 53-55SERK1 from the SERK1 N-terminal cap mediate specific interactions with the IDA peptide (Figures 4C, 6B).	DISCUSS
102	113	IDA peptide	chemical	In addition, residues 53-55SERK1 from the SERK1 N-terminal cap mediate specific interactions with the IDA peptide (Figures 4C, 6B).	DISCUSS
54	69	steroid hormone	chemical	These residues are not involved in the sensing of the steroid hormone brassinolide.	DISCUSS
70	82	brassinolide	chemical	These residues are not involved in the sensing of the steroid hormone brassinolide.	DISCUSS
53	75	hormone binding pocket	site	In both cases however, the co-receptor completes the hormone binding pocket.	DISCUSS
48	70	SERK1 binding surfaces	site	This fact together with the largely overlapping SERK1 binding surfaces in HAESA and BRI1 allows us to speculate that SERK1 may promote high-affinity peptide hormone and brassinosteroid sensing by simply slowing down dissociation of the ligand from its cognate receptor.	DISCUSS
74	79	HAESA	protein	This fact together with the largely overlapping SERK1 binding surfaces in HAESA and BRI1 allows us to speculate that SERK1 may promote high-affinity peptide hormone and brassinosteroid sensing by simply slowing down dissociation of the ligand from its cognate receptor.	DISCUSS
84	88	BRI1	protein	This fact together with the largely overlapping SERK1 binding surfaces in HAESA and BRI1 allows us to speculate that SERK1 may promote high-affinity peptide hormone and brassinosteroid sensing by simply slowing down dissociation of the ligand from its cognate receptor.	DISCUSS
117	122	SERK1	protein	This fact together with the largely overlapping SERK1 binding surfaces in HAESA and BRI1 allows us to speculate that SERK1 may promote high-affinity peptide hormone and brassinosteroid sensing by simply slowing down dissociation of the ligand from its cognate receptor.	DISCUSS
149	164	peptide hormone	protein_type	This fact together with the largely overlapping SERK1 binding surfaces in HAESA and BRI1 allows us to speculate that SERK1 may promote high-affinity peptide hormone and brassinosteroid sensing by simply slowing down dissociation of the ligand from its cognate receptor.	DISCUSS
10	15	plant	taxonomy_domain	Different plant peptide hormone families contain a C-terminal (Arg)-His-Asn motif, which in IDA represents the co-receptor recognition site.	FIG
16	40	peptide hormone families	protein_type	Different plant peptide hormone families contain a C-terminal (Arg)-His-Asn motif, which in IDA represents the co-receptor recognition site.	FIG
62	81	(Arg)-His-Asn motif	structure_element	Different plant peptide hormone families contain a C-terminal (Arg)-His-Asn motif, which in IDA represents the co-receptor recognition site.	FIG
92	95	IDA	protein	Different plant peptide hormone families contain a C-terminal (Arg)-His-Asn motif, which in IDA represents the co-receptor recognition site.	FIG
111	139	co-receptor recognition site	site	Different plant peptide hormone families contain a C-terminal (Arg)-His-Asn motif, which in IDA represents the co-receptor recognition site.	FIG
0	44	Structure-guided multiple sequence alignment	experimental_method	Structure-guided multiple sequence alignment of IDA and IDA-like peptides with other plant peptide hormone families, including CLAVATA3 – EMBRYO SURROUNDING REGION-RELATED (CLV3/CLE), ROOT GROWTH FACTOR – GOLVEN (RGF/GLV), PRECURSOR GENE PROPEP1 (PEP1) from Arabidopsis thaliana.	FIG
48	51	IDA	protein	Structure-guided multiple sequence alignment of IDA and IDA-like peptides with other plant peptide hormone families, including CLAVATA3 – EMBRYO SURROUNDING REGION-RELATED (CLV3/CLE), ROOT GROWTH FACTOR – GOLVEN (RGF/GLV), PRECURSOR GENE PROPEP1 (PEP1) from Arabidopsis thaliana.	FIG
56	73	IDA-like peptides	chemical	Structure-guided multiple sequence alignment of IDA and IDA-like peptides with other plant peptide hormone families, including CLAVATA3 – EMBRYO SURROUNDING REGION-RELATED (CLV3/CLE), ROOT GROWTH FACTOR – GOLVEN (RGF/GLV), PRECURSOR GENE PROPEP1 (PEP1) from Arabidopsis thaliana.	FIG
85	90	plant	taxonomy_domain	Structure-guided multiple sequence alignment of IDA and IDA-like peptides with other plant peptide hormone families, including CLAVATA3 – EMBRYO SURROUNDING REGION-RELATED (CLV3/CLE), ROOT GROWTH FACTOR – GOLVEN (RGF/GLV), PRECURSOR GENE PROPEP1 (PEP1) from Arabidopsis thaliana.	FIG
91	115	peptide hormone families	protein_type	Structure-guided multiple sequence alignment of IDA and IDA-like peptides with other plant peptide hormone families, including CLAVATA3 – EMBRYO SURROUNDING REGION-RELATED (CLV3/CLE), ROOT GROWTH FACTOR – GOLVEN (RGF/GLV), PRECURSOR GENE PROPEP1 (PEP1) from Arabidopsis thaliana.	FIG
127	171	CLAVATA3 – EMBRYO SURROUNDING REGION-RELATED	protein_type	Structure-guided multiple sequence alignment of IDA and IDA-like peptides with other plant peptide hormone families, including CLAVATA3 – EMBRYO SURROUNDING REGION-RELATED (CLV3/CLE), ROOT GROWTH FACTOR – GOLVEN (RGF/GLV), PRECURSOR GENE PROPEP1 (PEP1) from Arabidopsis thaliana.	FIG
173	181	CLV3/CLE	protein_type	Structure-guided multiple sequence alignment of IDA and IDA-like peptides with other plant peptide hormone families, including CLAVATA3 – EMBRYO SURROUNDING REGION-RELATED (CLV3/CLE), ROOT GROWTH FACTOR – GOLVEN (RGF/GLV), PRECURSOR GENE PROPEP1 (PEP1) from Arabidopsis thaliana.	FIG
184	211	ROOT GROWTH FACTOR – GOLVEN	protein_type	Structure-guided multiple sequence alignment of IDA and IDA-like peptides with other plant peptide hormone families, including CLAVATA3 – EMBRYO SURROUNDING REGION-RELATED (CLV3/CLE), ROOT GROWTH FACTOR – GOLVEN (RGF/GLV), PRECURSOR GENE PROPEP1 (PEP1) from Arabidopsis thaliana.	FIG
213	220	RGF/GLV	protein_type	Structure-guided multiple sequence alignment of IDA and IDA-like peptides with other plant peptide hormone families, including CLAVATA3 – EMBRYO SURROUNDING REGION-RELATED (CLV3/CLE), ROOT GROWTH FACTOR – GOLVEN (RGF/GLV), PRECURSOR GENE PROPEP1 (PEP1) from Arabidopsis thaliana.	FIG
223	245	PRECURSOR GENE PROPEP1	protein_type	Structure-guided multiple sequence alignment of IDA and IDA-like peptides with other plant peptide hormone families, including CLAVATA3 – EMBRYO SURROUNDING REGION-RELATED (CLV3/CLE), ROOT GROWTH FACTOR – GOLVEN (RGF/GLV), PRECURSOR GENE PROPEP1 (PEP1) from Arabidopsis thaliana.	FIG
247	251	PEP1	protein_type	Structure-guided multiple sequence alignment of IDA and IDA-like peptides with other plant peptide hormone families, including CLAVATA3 – EMBRYO SURROUNDING REGION-RELATED (CLV3/CLE), ROOT GROWTH FACTOR – GOLVEN (RGF/GLV), PRECURSOR GENE PROPEP1 (PEP1) from Arabidopsis thaliana.	FIG
258	278	Arabidopsis thaliana	species	Structure-guided multiple sequence alignment of IDA and IDA-like peptides with other plant peptide hormone families, including CLAVATA3 – EMBRYO SURROUNDING REGION-RELATED (CLV3/CLE), ROOT GROWTH FACTOR – GOLVEN (RGF/GLV), PRECURSOR GENE PROPEP1 (PEP1) from Arabidopsis thaliana.	FIG
4	13	conserved	protein_state	The conserved (Arg)-His-Asn motif is highlighted in red, the central Hyp residue in IDLs and CLEs is marked in blue.	FIG
14	33	(Arg)-His-Asn motif	structure_element	The conserved (Arg)-His-Asn motif is highlighted in red, the central Hyp residue in IDLs and CLEs is marked in blue.	FIG
69	72	Hyp	residue_name	The conserved (Arg)-His-Asn motif is highlighted in red, the central Hyp residue in IDLs and CLEs is marked in blue.	FIG
84	88	IDLs	protein_type	The conserved (Arg)-His-Asn motif is highlighted in red, the central Hyp residue in IDLs and CLEs is marked in blue.	FIG
93	97	CLEs	protein_type	The conserved (Arg)-His-Asn motif is highlighted in red, the central Hyp residue in IDLs and CLEs is marked in blue.	FIG
28	33	SERK1	protein	Our experiments reveal that SERK1 recognizes a C-terminal Arg-His-Asn motif in IDA.	DISCUSS
58	75	Arg-His-Asn motif	structure_element	Our experiments reveal that SERK1 recognizes a C-terminal Arg-His-Asn motif in IDA.	DISCUSS
79	82	IDA	protein	Our experiments reveal that SERK1 recognizes a C-terminal Arg-His-Asn motif in IDA.	DISCUSS
13	23	this motif	structure_element	Importantly, this motif can also be found in other peptide hormone families (Figure 7).	DISCUSS
51	75	peptide hormone families	protein_type	Importantly, this motif can also be found in other peptide hormone families (Figure 7).	DISCUSS
20	32	CLE peptides	chemical	Among these are the CLE peptides regulating stem cell maintenance in the shoot and the root.	DISCUSS
32	36	CLEs	protein_type	It is interesting to note, that CLEs in their mature form are also hydroxyprolinated dodecamers, which bind to a surface area in the BARELY ANY MERISTEM 1 receptor that would correspond to part of the IDA binding cleft in HAESA.	DISCUSS
46	57	mature form	protein_state	It is interesting to note, that CLEs in their mature form are also hydroxyprolinated dodecamers, which bind to a surface area in the BARELY ANY MERISTEM 1 receptor that would correspond to part of the IDA binding cleft in HAESA.	DISCUSS
67	84	hydroxyprolinated	protein_state	It is interesting to note, that CLEs in their mature form are also hydroxyprolinated dodecamers, which bind to a surface area in the BARELY ANY MERISTEM 1 receptor that would correspond to part of the IDA binding cleft in HAESA.	DISCUSS
85	95	dodecamers	structure_element	It is interesting to note, that CLEs in their mature form are also hydroxyprolinated dodecamers, which bind to a surface area in the BARELY ANY MERISTEM 1 receptor that would correspond to part of the IDA binding cleft in HAESA.	DISCUSS
113	125	surface area	site	It is interesting to note, that CLEs in their mature form are also hydroxyprolinated dodecamers, which bind to a surface area in the BARELY ANY MERISTEM 1 receptor that would correspond to part of the IDA binding cleft in HAESA.	DISCUSS
133	163	BARELY ANY MERISTEM 1 receptor	protein_type	It is interesting to note, that CLEs in their mature form are also hydroxyprolinated dodecamers, which bind to a surface area in the BARELY ANY MERISTEM 1 receptor that would correspond to part of the IDA binding cleft in HAESA.	DISCUSS
201	218	IDA binding cleft	site	It is interesting to note, that CLEs in their mature form are also hydroxyprolinated dodecamers, which bind to a surface area in the BARELY ANY MERISTEM 1 receptor that would correspond to part of the IDA binding cleft in HAESA.	DISCUSS
222	227	HAESA	protein	It is interesting to note, that CLEs in their mature form are also hydroxyprolinated dodecamers, which bind to a surface area in the BARELY ANY MERISTEM 1 receptor that would correspond to part of the IDA binding cleft in HAESA.	DISCUSS
8	13	plant	taxonomy_domain	Diverse plant peptide hormones may thus also bind their LRR-RK receptors in an extended conformation along the inner surface of the LRR domain and may also use small, shape-complementary co-receptors for high-affinity ligand binding and receptor activation.	DISCUSS
14	30	peptide hormones	protein_type	Diverse plant peptide hormones may thus also bind their LRR-RK receptors in an extended conformation along the inner surface of the LRR domain and may also use small, shape-complementary co-receptors for high-affinity ligand binding and receptor activation.	DISCUSS
56	72	LRR-RK receptors	protein_type	Diverse plant peptide hormones may thus also bind their LRR-RK receptors in an extended conformation along the inner surface of the LRR domain and may also use small, shape-complementary co-receptors for high-affinity ligand binding and receptor activation.	DISCUSS
79	100	extended conformation	protein_state	Diverse plant peptide hormones may thus also bind their LRR-RK receptors in an extended conformation along the inner surface of the LRR domain and may also use small, shape-complementary co-receptors for high-affinity ligand binding and receptor activation.	DISCUSS
132	142	LRR domain	structure_element	Diverse plant peptide hormones may thus also bind their LRR-RK receptors in an extended conformation along the inner surface of the LRR domain and may also use small, shape-complementary co-receptors for high-affinity ligand binding and receptor activation.	DISCUSS
160	165	small	protein_state	Diverse plant peptide hormones may thus also bind their LRR-RK receptors in an extended conformation along the inner surface of the LRR domain and may also use small, shape-complementary co-receptors for high-affinity ligand binding and receptor activation.	DISCUSS
167	186	shape-complementary	protein_state	Diverse plant peptide hormones may thus also bind their LRR-RK receptors in an extended conformation along the inner surface of the LRR domain and may also use small, shape-complementary co-receptors for high-affinity ligand binding and receptor activation.	DISCUSS
187	199	co-receptors	protein_type	Diverse plant peptide hormones may thus also bind their LRR-RK receptors in an extended conformation along the inner surface of the LRR domain and may also use small, shape-complementary co-receptors for high-affinity ligand binding and receptor activation.	DISCUSS