EMBO/SourceData huggingface dataset:
Figure 3Representative Western blots of GFP, p-cJun and GAPDH (B) from HeLa cells non transfected (NT) or transfected with GFP alone (GFP), GFP-tagged DLK wild-type (DLK-WT-GFP), kinase dead mutant (DLK-KD-GFP), leucine zipper domain mutant (DLK-LZ-GFP) and a palmitoyl-site mutant (DLK-CS-GFP)quantification of relative c-Jun phosphorylation levels (C) from HeLa cells non transfected (NT) or transfected with GFP alone (GFP), GFP-tagged DLK wild-type (DLK-WT-GFP), kinase dead mutant (DLK-KD-GFP), leucine zipper domain mutant (DLK-LZ-GFP) and a palmitoyl-site mutant (DLK-CS-GFP) (n = 4-7 biological replicates; series of unpaired t tests /Mann-Whitney U tests with DLK-WT-GFP followed by a Holm-Sidak correction). Data information: All graphs represent mean ± SEM. *p < 0.05 and ***p < 0.001.D. Representative images and zooms of HeLa cells expressing GFP alone or the different GFP-tagged DLK mutants. Data information: Scale bar represents 100 μm in (D) zooms in (D).E-F. Representative Western blots of GFP, α-tubulin and Na+/K+-ATPase from cytosolic and membrane fractions (E) and quantification of the percentage of DLK localized in the membrane and cytosolic fraction (F) from HeLa cells expressing GFP alone or the different GFP-tagged DLK mutants (n = 4-5 biological replicates; series of unpaired t tests /Mann-Whitney U tests with DLK-WT-GFP followed by a Holm-Sidak correction). Data information: All graphs represent mean ± SEM. *p < 0.05 and ***p < 0.001.G-I. Representative stills (G), representative kymographs (H) and quantification of the number of GFP-positive particles (I) from time-lapse recordings of the different GFP-tagged DLK mutants in DIV6 cultured embryonic DRG neurons (n = 31-65 neurons/condition; series of Mann-Whitney U tests with DLK-WT-GFP followed by a Holm-Sidak correction). Data information: Arrowheads point to individual DLK-GFP positive structures in G All graphs represent mean ± SEM. *p < 0.05 and ***p < 0.001. Scale bar represents 10 μm in (G) , 5 μm in (H)J-L. Representative stills (J), kymographs (K) and quantification of the number of DLK-GFP positive particles (L) from time-lapse recordings of DIV6 DRG neurons overexpressing GFP-tagged DLK and treated with control (DMSO) or DLK inhibitor GNE-3511 (DLKi) for 3h (n = 22-46 neurons/condition; Unpaired t test). Data information: Arrowheads point to individual DLK-GFP positive structures in J. All graphs represent mean ± SEM. *p < 0.05 and ***p < 0.001. Scale bar represents 10 μm in (J), 5 μm in (K)
Figure 1A, Primary HBMEC were challenged with type I (RH) or type II (ME49) strains of T. gondii for the indicated time points. Cell lysates were used to probe for total Akt and phospho-Ser473 Akt by immunoblot.B, C, Mouse endothelial cells (mHEVc; B) and human retinal pigment epithelial cells (RPE, C) were challenged with RH T. gondii followed by assessment of Akt phosphorylation.B, C, Mouse endothelial cells (mHEVc; B) and human retinal pigment epithelial cells (RPE, C) were challenged with RH T. gondii followed by assessment of Akt phosphorylation.D, HBMEC were challenged with either live or killed T. gondii. Cell lysates were subject to immunoblotting as indicated.E, HBMEC were transiently transfected with a plasmid encoding PH-Akt-GFP. Cells treated with or without LY294002 (20 µM) for 1 h prior to challenge with T. gondii-RFP. Cells were examined by immunofluorescence at 5 min post-challenge to examine accumulation of PH-Akt-GFP around the parasites.F, HBMEC were incubated with LY294002 or vehicle for 1 h prior to challenge with T. gondii. Densitometry data represent means ± SEM of 4 experiments. A vertical line was inserted between densitometry data from control and LY294002-treated cells to indicate that band densities from infected cells treated with or without LY294002 are compared to bands from their respective uninfected cells, which were given an arbitrary number of 1.G, HBMEC were transiently transfected with control siRNA or PI3K p110α siRNA. Cells expressing either control siRNA or PI3K p110α siRNA were challenged with T. gondii 48 h after transfection. Cell lysates were subject to immunoblotting as indicated. Densitometry data are shown as above and represent means ± SEM of 3 experiments. Results shown are representative of 3-4 independent experiments.
Figure 2A, HBMEC, mHEVc and human RPE cells were incubated with or without Akt inhibitor IV (1.25 µM) for 1 h prior to challenge with T. gondii. Monolayers were examined by light microscopy 2 h and 24 h post-challenge.B, HBMEC were transfected with control siRNA or Akt siRNA. Cells were then challenged with T. gondii 48 h after transfection. Monolayers were examined microscopically 24 h post-challenge.C, RAW 264.7 were incubated with or without Akt inhibitor IV for 1 h prior to challenge with T. gondii. Monolayers were examined by light microscopy 2 h and 24 h post-challenge.D, mHEVc-LC3-EGFP cells were incubated with or without Akt inhibitor IVfollowed by challenge with T. gondii-RFP. Monolayers were examined by fluorescence microscopy 5 h post-challenge. Arrowheads indicate accumulation of LC3 around the parasite.E, HBMEC were treated with or without Akt inhibitor IV for 1 h prior to challenge with T. gondii (T) and then processed for electron microscopy at 5 h post-challenge. Images at the bottom represent magnification of the areas within the boxes. Arrow indicates the PVM; arrowhead indicates the double membrane structure around the vacuole.F, Control or Akt inhibitor IV-treated HBMEC were challenged with T. gondii-YFP. Expression of LAMP-1 was examined by fluorescent microscopy 8 h post-challenge. Arrowheads indicate accumulation of LAMP-1 around the parasiteG, H, mHEVc cells were transfected with Beclin 1 siRNA (G), Atg7 siRNA (H) or control siRNA. After 48 h, cells were treated with or without Akt inhibitor IV for 1 h prior to challenge with T. gondii. Monolayers were examined by light microscopy at 24 h.I, mHEVc were treated with or without Akt inhibitor IV and infected with T. gondii. 1 h post infection cells were treated with or without leupeptin plus pepstatin (Lys inhibitors). Monolayers were examined microscopically 24 h post-challenge.J, Mouse microglia were incubated with or without Akt inhibitor IV. 3-methyl adenine (3MA; 10 mM) or vehicle were added 2 h post-challenge with T. gondii. Monolayers were examined microscopically 24 h post-challenge. Results are shown as the mean ± SEM and are representative of 3 independent experiments.
Figure 3A, HBMEC were treated with or without pertussis toxin (PTx; 100 ng/mL) for 4 h prior to challenge with T. gondii. Cell lysates were obtained at 5, 15 or 30 min post-incubation with T. gondii and used to examine total Akt and phospho-Akt serine 473 by immunoblot. Densitometry data represent means ± SEM of 3 experiments. A vertical line was inserted between densitometry data from control and PTx-treated cells to indicate that band densities from infected cells treated with or without PTx were compared to bands from their respective uninfected cells, which were given an arbitrary number of 1. HBMEC were also treated with or without LPA (10 µM) in the presence or absence of PTx. Cell lysates were obtained at 5 min and subjected to immunoblottingB, HBMEC were transfected with MyD88 siRNA or control siRNA followed by challenge with T gondii after 48 h. Cell lysates were used to examine total Akt and phospho-serine 473 Akt by immunoblot. Results shown are representative of 3 independent experiments.
Figure 4A, HBMEC cells were challenged with RH T. gondii and cell lysates were obtained to probe for total EGFR, phospho-tyrosine 1068 EGFR and phospho- tyrosine 1148 EGFR by immunoblot.B, HBMEC were challenged with live vs killed tachyzoites. Total EGFR and phospho-tyrosine 1068 EGFR expression was examined by immunoblot.C, D, Human RPE cells (C) and mouse microglia (D) were challenged with RH T. gondii and total EGFR and phospho-tyrosine 1068 EGFR expression was examined by immunoblot. Results shown are representative of 3 independent experiments.
Figure 5A, mHEVc cells were transfected with control siRNA or EGFR siRNA. Expression of EGFR and actin were assessed by immunoblot 48 h post-transfection. mHEVc cells expressing either control siRNA or EGFR siRNA were challenged with T. gondii. Cell lysates were used to examine the expression total Akt or phospho-Ser473 Akt by immunoblot.B, Mouse microglia were treated with or without AG1478 (1 µM) 1 h prior to challenge with T. gondii. Cell lysates were used to examine the expression total Akt or phospho-Ser473 Akt by immunoblot. Densitometry data represent means ± SEM of 3 experiments. A vertical line was inserted between densitometry data from control siRNA and EGFR siRNA or control and AG1478-treated cells to indicate that band densities from infected control cells or infected cells subjected to EGFR blockade were compared to bands from their respective uninfected cells, which were given an arbitrary number of 1. Results shown are representative of 3 independent experiments.
Figure 6A, HBMEC were incubated with AG1478 (1 µM) 1 h prior to challenge with T. gondii. Monolayers were examined by light microscopy at 2 and 24 h.B, Human RPE cells transfected with either EGFR or control siRNA were challenged with T. gondii followed by examination of monolayers by light microscopy at 24 h.C, Mouse bone marrow-derived macrophages were incubated with AG1478 and challenged with T. gondii. Monolayers were examined by light microscopy at 2 and 24 h.D, Parental CHO and CHO-EGFR cells were challenged with RH T. gondii. Monolayers were examined microscopically 2 h or 24 h post-challenge.E, mHEVc-LC3-EGFP cells transfected with control siRNA or EGFR siRNA were challenged with T. gondii-RFP. Monolayers were examined by fluorescence microscopy 5 h post-challenge to determine the percentage of endothelial cells with LC3 accumulation around the parasite.F, HBMEC cells treated with or without AG1478 were challenged with either T. gondii-YFP. Expression of LAMP-1 was examined by fluorescent microscopy 8 h post-challenge. The percentages of endothelial cells with LAMP-1 accumulation of around the parasite were determined.G, H, mHEVc cells transfected with Beclin1 siRNA (G) or Atg7 siRNA (H) were transfected with EGFR siRNA or treated with or without AG1478 followed by challenge with T. gondii. Monolayers were examined by light microscopy 24 h post-challenge. Results are shown as the mean ± SEM and are representative of 3 independent experiments.
Figure 7HBMEC were treated with or without GM6001 (10 µM) for 1 h prior to challenge with T. gondii (A) or with Pertussis Toxin (PTx; 100 ng/ml) for 4 h prior to parasite challenge (B). Cell lysates were used to examine total EGFR and phospho-tyrosine 1068 EGFR by immunoblot. Densitometry data represent means ± SEM of 3 experiments. A vertical line was inserted between densitometry data from control and GM6001- or PTX-treated cells to indicate that band densities from infected cells treated with or without these inhibitors are compared to bands from their respective uninfected cells, which were given an arbitrary number of 1. Results shown are representative of 3 independent experiments.HBMEC were treated with or without GM6001 (10 µM) for 1 h prior to challenge with T. gondii (A) or with Pertussis Toxin (PTx; 100 ng/ml) for 4 h prior to parasite challenge (B). Cell lysates were used to examine total EGFR and phospho-tyrosine 1068 EGFR by immunoblot. Densitometry data represent means ± SEM of 3 experiments. A vertical line was inserted between densitometry data from control and GM6001- or PTX-treated cells to indicate that band densities from infected cells treated with or without these inhibitors are compared to bands from their respective uninfected cells, which were given an arbitrary number of 1. Results shown are representative of 3 independent experiments.
Figure 8A, B, C HBMEC were challenged with ΔHx (WT), MIC1 ko, MIC3 ko, MIC1-3 ko T. gondii at MOIs that yielded similar percentages of infected cells (A).Cell lysates were obtained and used to examine total EGFR and phospho-tyrosine 1068 EGFR (B) or total Akt and phospho-Ser 473 Akt (C) by immunoblot.HBMEC were incubated with 10 nM of recombinant MIC4, MIC3, M2AP or MIC6 for 15 minutes followed by examination of total EGFR and phospho-tyrosine 1068 EGFR (D) or total Akt and phospho-Ser473 (E) by immunoblot. Densitometry data represent means ± SEM of 4 experiments. Band densities from infected cells or cells treated with MICs were compared to bands from uninfected or untreated cells (Un), which were given an arbitrary number of 1. Results shown are representative of 4 independent experiments.
Figure 9A, hmCD40 mHEVc expressing LC3-EGFP were treated with or without CD154 followed by challenge with T. gondii-RFP in the presence or absence of EGF (50 ng/ml) or AG1478 (1 µM). LC3 accumulation around T. gondii was assessed by immunofluorescence. B, mHEVc-LC3-EGFP cells were infected with T. gondii-T. gondii. Cells were treated with vehicle or rapamycin (1 µM) 2 h after challenge with T. gondii in the presence or absent of EGF or AG1478. Recruitment of LC3 around the parasite was examined at 5 h after challenge with T. gondii.. C, hmCD40 mHEVc-LC3-EGFP cells were treated with or without CD154 followed by challenged with WT, MIC1 ko, MIC1 ko+MIC1, MIC3 ko, MIC3 ko+MIC3, MIC1-3 ko, MIC1-3 ko+MIC1-3 tachyzoites. LC3 accumulation around the parasite was examined by fluorescence microscopy 5 h post-challenge. D, hmCD40 mHEVc-LC3-EGFP treated with or without CD154 were challenged with WT, MIC1 ko, MIC1 ko+MIC1, MIC3 ko, MIC3 ko+MIC3, MIC1-3 ko or MIC1-3 ko+MIC1-3 tachyzoites. Parasite load was examined 24 h post-challenge.E, HBMEC cells were challenged with WT, MIC1 ko, MIC3 ko, MIC1-3 ko tachyzoites followed by treatment with vehicle or rapamycin. Parasite load was examined 24 h post-challenge. F, HBMEC treated with or without CD154 or IFN-γ/TNF-α were challenged with WT, MIC1 ko, MIC3 ko, MIC1-3 ko tachyzoites. Monolayers were examined microscopically at 24 h post-challenge.G, hmCD40 mHEVc cells treated with or without CD154 were infected with either WT or MIC1-3 ko tachyzoites in the presence of complete medium (CM) alone or medium plus MIC3, MIC4, M2AP or MIC6 (all 10 nM). Parasite load was determined microscopically 24 h post challenge. Results shown are representative of 3-4 independent experiments.
Figure 1Size exclusion chromatography profiles of recombinant proteins used in this study. AU: arbitrary units; WT: wild type; FL: full-length.
Figure 2Analysis of the interaction between CtUba4 and GST-CtUrm1 (ratio 2:1 or 0.5:1 when marked with an asterisk) in the presence of nucleotide derivates by GST pull-down resolved by SDS-PAGE and visualized with Coomassie stain.Functional analyses of ScUba4 mutant yeast using APM-gel retardation (top) and viability in response to rapamycin (bottom). PAGE was supplemented with APM to retard the migration of thiolated tRNAs and allow their visualization by northern blot using an anti-tRNA<sub>UU<em>C</em></sub><sup>Gl<em>u</em></sup>; probe. APM: ([N-Acryloyl-amino]phenyl)mercuric chloride; YPD: yeast extract peptone dextrose. All residue numbering follows the CtUba4 sequence, but the respective ScUba4 numbering is added in subscript.
Figure 3Interaction analysis of WT and mutated CtUba4 with GST-CtUrm1 by GST pull-down in the presence of 1mM ATP. CtUba4C202K covalently linked to GST-CtUrm1 is marked by an asterisk.
Figure 4Analysis of covalent adduct formation between CtUba4 WT or C202 mutants and carboxylated (-OH) or thiocarboxylated (-SH) CtUrm1 in the presence or absence of TBH, DTT, TCEP and HA, respectively. ATP: Adenosine triphosphate TBH: tert-Butyl hydroperoxide HA: Hydroxylamine; DTT: 1,4-Dithiothreitol; TCEP: Tris(2-carboxyethyl)phosphine.Analysis of covalent adduct formation between CtUba4 WT/cysteine mutants and CtUrm1-COSH in the presence of oxidizing agents. HP: Hydrogen peroxide; D: Diamide.Phenotypic analysis of ScUba4 mutant yeast strains in response to rapamycin.MS/MS spectrum of the K202-ε-GGH containing peptide from CtUba4C202K. A representative annotated fragmentation spectrum is shown with the b- and y-ions marked in red and blue, respectively. The precursor ion at m/z 591,98 is labelled in green. The peptide sequence is shown at the top with the collision-induced fragmentation pattern. The Urm1 conjugation site was identified by detection of the GGH remnant motif generated by chymotryptic digestion.Analysis of covalent adduct formation between CtUba4 WT or Cys202 mutants and thiocarboxylated (-SH) CtUrm1 in the presence or absence of TBH and HA, respectively.
Figure 1(A) Genome-wide ubiquitin binding profiles identify numerous regions of H2B-ubiquitylation in WT cells and distinct sites of non-H2B ubiquitylation ('ubiquitin-hotspot', ub-hotspot, ub-HS) which persist in h2b-K123R and rad6∆ strains, and increase in cdc48 mutants (cdc48-6). A 90 kb stretch of chromosome XIII (ChrXIII) is depicted. Chromatin immunoprecipitation was performed using the FK2 ubiquitin antibody (see also Appendix Fig. S1A) and enriched DNA was analyzed on NimbleGen arrays (Chip-chip). DNA from non-specific IgG-ChIP experiments served as background control. Significantly enriched regions are marked by bars above the respective ChIP-chip tracks and are summarized in Dataset EV1. Data represent means from two independent replicates, except for ubiquitin (FK2) in rad6∆ and IgG-ChIP in WT (n = 1). All experiments, including those using cdc48-6 and other temperature-sensitive (ts) alleles, were performed at 30°C (semipermissive temperature for ts-alleles) unless stated otherwise.(B) Seven ub-HSs show strong correlation between ubiquitin binding and Slx8 enrichment (Slx8-9myc ChIP). 16-kb-windows of the indicated regions centered around the ub-HSs are depicted for ubiquitin and Slx8 binding profiles. Ubiquitin (FK2) data for WT and cdc48-6 are from the same experiment as depicted in (A). Data represent means from two independent replicates.(D) Slx8 and Slx5 are recruited to ub-HSs. DNA from Slx8-9myc (top) or 3HA-Slx5 (bottom) ChIP experiments of the indicated strains was analyzed by quantitative real-time PCR (ChIP-qPCR) at selected ub-HSs. Data represent mean ± standard deviation (SD, n = 2). Consistent with a previous study, we did not observe any Slx8 enrichment at centromeres (van de Pasch et al, 2013), however, we note that we could not confirm the reported centromere binding of Slx5 (see also Appendix Fig. S2E).(E) K48-linked ubiquitin chains accumulate in a cdc48 mutant (cdc48-3). Ub-K48 ChIP followed by qPCR for same loci as in (D) are depicted. See also Fig. EV1C-D. Data represent means ± SD (n = 2).(F) Slx5 and Slx8 are required for ub-HS formation. Ub-K48 ChIP-qPCR in strains lacking one subunit of the Slx5/Slx8 complex (slx5∆, slx8∆). Data represent means ± SD (n = 3).(G) Ufd1 and Npl4 act in concert with Cdc48 to remove ubiquitylated proteins from ub-HS sites. Ub-K48 ChIP for the indicated strains grown at the semi-permissive temperature of 30°C. Data represent means ± SD (n = 2).
Figure 2B) A 39 bp fragment of ub-HS4 is sufficient to drive ectopic ub-HS formation. Fragments of ub-HS4 were integrated ectopically and ub-K48 ChIP-qPCR was performed for the endogenous ub-HS5 and the ectopic ub-HS4 fragments as depicted in (A). contr.: control, empty YI128-vector was integrated at LEU2. Experiments were performed in cdc48‑6 background. Data represent means ± SD (n = 2). Experimental mapping and bioinformatic prediction identify a similar ub-HS-motif. Comparison between the experimentally mapped ub-HS4 F7 (B) and the consensus motif of all ub-HSs identified by the MEME software.E) Euc1 binds to the ub-HS-motif in a Y1H assay. Gal4-AD- or Gal4-AD-Euc1-encoding plasmids were transformed into a Y1H reporter strain as described in (D). Serial dilutions were spotted on control plates and plates lacking histidine with 20mM 3-amino-triazole (3AT). Cells were grown at 30°C for 3 days.F) Euc1 is required for formation of ub-HSs. ChIP with ub-K48 specific antibodies was performed for the indicated strains and enriched DNA was analyzed by qPCR. Data represent means ± SD (n = 4).Euc1 binds to endogenous ub-HSs. Genome-wide binding profiles of K48-linked ubiquitin chains were obtained in ChIP-chip experiments as described in Fig. 1A. Euc1-ChIP experiments were performed with a polyclonal antibody raised against Euc1 aa 292-462. Data represent means from two independent replicates.Euc1 binds to endogenous ub-HSs. Genome-wide binding profiles of Euc1 were obtained in ChIP-chip experiments as described in Fig. 1A. Euc1-ChIP experiments were performed with a polyclonal antibody raised against Euc1 aa 292-462. Data represent means from two independent replicates.
Figure 3(C) Euc1 can induce transactivation via its N-terminal 30 amino acids. Euc1 constructs under the endogenous EUC1 promoter were transformed in a reporter strain as described for Fig. 2D and serial dilutions were spotted on control or selective media to test HIS3-activation. Cells were grown at 30°C for 3 days.(D) Quantification of HIS3 mRNA levels from strains used in (C). Cells were grown in liquid media with selection for the transformed plasmids (SC-Leu), harvested in logarithmic growth phase and total mRNA was prepared. After reverse transcription, HIS3 mRNA levels were quantified using qPCR (RT-qPCR), normalized first to ACT1 mRNA and then to the empty vector control strain. Data represent means ± SD (n = 4). p = 2.43*10-5 (Student's t-test).
Figure 4(A) Euc1 interacts with SUMO pathway proteins in a yeast two-hybrid (Y2H) assay. A Y2H reporter strain (PJ69-7a) was transformed with Gal4 DNA-binding domain (BD) and Gal4 activation domain (AD) fusion constructs in the indicated combinations. AD-SUMO-GG can be conjugated to SUMOylation substrates, while AD-SUMO-AA is conjugation-deficient. Cells were spotted on control media or selective media (- His) and grown for 3 and 6 days, respectively.(B) Euc1 is SUMOylated by Ubc9, Siz1 and Siz2 on K231. Euc1 was immunoprecipitated from the indicated strains and eluates were probed by WB against SUMO (top) and Euc1 (bottom). An up-shifted band corresponding to Euc1SUMO was detected with both antibodies. Asterisks denote non-specific bands.(C) Euc1 is predominantly monoSUMOylated on lysine 231. Denaturing NiNTA-pulldowns (NiNTA-PD) with strains expressing His-tagged SUMO (HisSUMO) as indicated and 3FLAGEuc1 constructs under the control of an ADH promoter. Covalently SUMO-modified proteins were enriched and eluates probed with a FLAG antibody to visualize SUMOylated Euc1. Eluates were probed for SUMO to control for equal pull-down, Pgk1 was probed as input control. Euc1-KR denotes the K231R mutation here and hereafter.(D) Euc1 SUMOylation is required for ub-HS formation. Ub-K48 ChIP quantified by qPCR for the indicated strains. The ubx5∆ background was used to enhance the ubiquitin signal, similar results were obtained in a WT background. Data represent means ± SD (n = 3).(E) Euc1 ubiquitylation depends on Slx8 and partly on Euc1 SUMOylation. Denaturing NiNTA-PDs as described for (C) but with strains expressing His-ubiquitin (HisUbi) and 3FLAGEuc1 under the control of the ADH promoter. WBs were developed with a FLAG antibody to probe for 3FLAGEuc1, a ubiquitin blot served as PD-control and Dpm1 as input control. The slx8-CD allele carries the C206S, C209S-mutations (Xie et al, 2007).SUMOylated Euc1 is required to recruit Slx5 and Slx8 to ub-HSs. ChIP against Slx5 in the indicated genetic backgrounds were quantified by qPCR. Note that Slx5 is still recruited in the absence of Slx8 (3HA-Slx5 slx8∆), but not vice versa (Slx8-9myc slx5∆). Data for WT and 3HA-Slx5 in (F) and WTSUMOylated Euc1 is required to recruit Slx8 to ub-HSs. ChIP against Slx8 in the indicated genetic backgrounds were quantified by qPCR. Note that Slx5 is still recruited in the absence of Slx8 (3HA-Slx5 slx8∆), but not vice versa (Slx8-9myc slx5∆). Data for WT and Slx8-9myc in (G)