EMBO/SourceData huggingface dataset:
Figure 6Size of individual cilia in stem cell and transit amplifying cell regions of WT and Prom1 KO mice (A) and their density in the respective regions (B). 3 animals were analyzed for each genotype. The number of quantified cilia is indicated (n).Clonogenicity analysis of CLESCs treated with either Hdac6 inhibitor (Tubacin) and appropriate controls (Nitubacin and DMSO, C) Colonies were stained with crystal violetClonogenicity analysis of CLESCs treated with siArl13b and its siControl. Colonies were stained with crystal violetsiRNA knockdown efficiency of Arl13b (E) in Ki67 FUCCI-CLESCs was evaluated real-time RT-PCR analysis. The results are in arbitrary values after normalization for GapDHsiRNA knockdown efficiency of Hdac6 (F) in Ki67 FUCCI-CLESCs was evaluated real-time RT-PCR analysis. The results are in arbitrary values after normalization for GapDHFlow cytometry analysis and quantification of samples indicated in (E and F).Representative IF double staining and 3D reconstruction of the Prom1 (green) and AcTub (red) at the apical domain of polarized MDCK cells expressing Prom1 and its K138Q mutant (top panels). Black-white inserts show Prom1 signals only. Same cells were analyzed by SEM (bottom panels). Note that Prom1 is asymmetrically distributed along the primary cilium (white arrows) as observed in vivo (see Fig 2C) and mutation K138Q significantly impacts on the primary cilium length. MV, microvilli.IF staining and 3D reconstruction of AcTub-labeled (red) primary cilium at the apical membrane of parental MDCK cells (MDCK) and those cells transfected with Prom1 or its K138Q mutant. The images were used to quantify the primary cilium length (Appendix Figs S6B and C). Arrows indicate primary cilia with more than 4 μm in length.Co-immunoisolation (IS) analyses were performed with paramagnetic beads using antibodies against either Arl13b (K) Recovered materials were analyzed by immunoblotting against the indicated proteins. Brackets and asterisks indicate the plasma membrane and endoplasmic reticulum-associated forms of Prom1, respectively, while arrows show Arl13b. Arrowhead, immunoglobulin.Co-immunoisolation (IS) analyses were performed with paramagnetic beads using antibodies against either Prom1 (AC133) or with anti-FITC antibody as control (L). Recovered materials were analyzed by immunoblotting against the indicated proteins. Brackets and asterisks indicate the plasma membrane and endoplasmic reticulum-associated forms of Prom1, respectively, while arrows show Arl13b. Arrowhead, immunoglobulin.The ratio Arl13b/Prom1 immunoreactivities was quantified (n = 3) (M).
Figure 7Parental MDCK cells or those transfected with Prom1 or K138Q mutant were grown for 7 dpc Cells were observed by phase-contrast microscopy (A) Box-whisker plots show the number of domes per 600 mm2 (A). Three images were analyzed per experiment (n = 4). 4X magnification (inset in panel A).Parental MDCK cells or those transfected with Prom1 or K138Q mutant were grown for 7 dpc Cells were observed by SEM (B, top panels) or confocal laser scanning microscopy after DAPI staining (B, bottom panels, Individual cells within a given dome are indicated (B, top panels) and were quantified using three different planes (bottom, centre and top) of DAPI-labeled nuclei (B, bottom panels).Parental MDCK cells or those transfected with Prom1 or K138Q mutant were grown for 7 dpc (A-C) or as indicated (D). confocal laser scanning microscopy after DAPI staining Domes of similar size were evaluated (C). Means and standard deviations are displayed. 15 domes per independent experiment were examined (n = 3). Cell density at a given time of culture (7, 10 and 14 days) was determined by counting DAPI-labeled nuclei per 0.1 mm2 (D, n = 4).Cilia with a length of >4 µm were rarely observed in K138Q mutant and displayed an irregular shape with constrictions along their distal part as observed by SEM (arrows).Mutation in the Hdac6-binding site of Prom1 increases the release of Prom1+ vesicles. 16 h-conditioned medium was subjected to differential centrifugation for 5 min at 300 x g (P1); 20 min at 1,200 x g (P2); 30 min at 10,000 x g (P3) and 1 h at 200,000 x g (P4). In parallel, detergent cell lysates were prepared. The entire pellets and 1/40 of cell lysates were analyzed by immunoblotting using antibodies against human Prom1, AcTub and β-actin (F). Molecular mass markers are indicated. All three proteins were detected in the vesicle fractions (P3 and P4) suggesting Prom1+ vesicles are released from primary cilia and microvilli.Mutation in the Hdac6-binding site of Prom1 increases the release of Prom1+ vesicles. 16 h-conditioned medium was subjected to differential centrifugation for 5 min at 300 x g (P1); 20 min at 1,200 x g (P2); 30 min at 10,000 x g (P3) and 1 h at 200,000 x g (P4). In parallel, detergent cell lysates were prepared. The release of Prom1+ vesicles was quantified using its immunoreactivities associated with cell and vesicle fractions (G)
Figure 8The mRNA expression of SHH effector genes (Gli1/2 and Glis1-3) on laser microdissection captured samples were evaluated by real-time RT-PCR analysis. The results are in arbitrary values after normalization for GapDH. Each sample was isolated from distinct mice (n = 3).Representative IF staining of Gli1 (left panel, red) and Glis2 (right panel, red) on the stem cell and transit amplifying cell regions of lower incisor CLE at P7. Samples were counterstained with DAPI (blue). Dotted lines, basement membrane.3D reconstruction of Glis2 staining (see B, red) and its association with DAPI-labeled nuclei (blue). Nuclear transparency was set at 0 or 70% as indicated.Representative IF double staining of Glis2 (red, bottom panel) and AcTub (green, top and bottom panels) along stem cell-transit amplifying cell axis in lower incisor CLE at P7. Samples were counterstained with DAPI (blue). Note the association of Glis2 with primary cilia particularly in the transition zone between stem cell and transit amplifying cell regions.Volume of Sox2-positive region on the lower incisor CLE at P7 was evaluated in WT vs. Glis2 KO mice upon IF staining. Number of animals analyzed is indicated (n).Representative IF staining of Prom1 using specific antibodies targeting either its extracellular loop (top panels, green) or cytoplasmic C-terminal end (bottom panels, red) on the stem cell and transit amplifying cell regions of lower incisor CLE at P7 WT and Glis2 KO mice. Samples are counterstained with DAPI (blue). Dotted lines, basement membrane. Arrowheads marks approximate boundary of stem cell regions.Representative IF double staining of Glis2 (red) and AcTub (green) as a marker of primary cilia in stem cell region of WT vs. Prom1 KO mice. Note the reduction of Glis2 expression in Prom1-deficient animals.
Figure 9Proximity ligation assay analysis of Prom1 and Glis2 association (red) in stem cell and transit amplifying cell regions of lower incisor CLE at P7. As negative control, one conjugated primary antibody (anti-Glis2) was omitted. SCs, stem cells; TACs, transit amplifying cells.Time dependent Prom1 and Glis2 co-expression (proximity ligation assay) in the cultured CLESCs starved for 4 days, and then treated with SHH (100 ng/ml) and importazole (40 µM), an inhibitor of importin β1function. DMSO was used as vehicle control. Data are represented triplicated samples as mean and standard deviation.PCR array analyses were performed on LCM captured P7 CLE of Prom1 and Glis2 KO vs. WT mice (n = 3). Arrows indicated genes with expression changed for more than 2 folder increase or decrease.PCR array analyses were performed on LCM captured P7 CLE of Prom1 and Glis2 KO vs. WT mice (n = 3). The mRNA expression of gene significantly changed in the PCR array (in (C)) (D) was evaluated in WT, Prom1 and Glis2 KO mice by real-time RT-PCR analysis. Each sample was isolated from distinct mice (n = 3). The results are in arbitrary values after normalization for GapDH.PCR array analyses were performed on LCM captured P7 CLE of Prom1 and Glis2 KO vs. WT mice (n = 3). The mRNA expression of gene significantly changed in the Stat pathway members (E) was evaluated in WT, Prom1 and Glis2 KO mice by real-time RT-PCR analysis. Each sample was isolated from distinct mice (n = 3). The results are in arbitrary values after normalization for GapDH.Chromatin IP analysis of binding of Glis2 to Stat3 promoter (see Appendix Fig S9D) in the absence or presence of SHH at different concentration as indicated on triplicated samples, using specific anti-Glis2 antibodies and rabbit IgG as control.
Figure 1(A) Three glycosylated forms of endogenous SMO protein are shown. NIH3T3 cells were harvested and treated with indicated glycosidases. Black bracket indicates mature glycosylated form and grey bracket indicates core glycosylated form. The representative results of three independent experiments are shown.(C) PTCH1 inhibited the Endo H-resistant glycosylation of SMO. HEK293T cells were co-transfected with the SMO and PTCH1 expression plasmids. After 48 h, the cells were harvested, lysed, and treated with indicated glycosidases. Results shown are representative of three independent experiments.(D) Quantification of Endo H-resistant form of SMO shown in (C). Three independent experiments were quantified by Image J and expressed as a percentage of the total SMO protein.(E) Shh increased the Endo H-resistant form of SMO. Cells were transfected as indicated for 24 h, and incubated with ShhN conditioned medium for an additional 24 h. Cells were harvested and analyzed as in (C). Results shown are representative of three independent experiments.(F) Quantification of Endo H-resistant form of SMO shown in (E). Three independent experiments were quantified by Image J and expressed as a percentage of the total SMO protein.(G) Shh increased the Endo H-resistant form of endogenous SMO in MEF cells. Results shown are representative of three independent experiments.(H) Densitometric analysis of Endo H-resistant form of SMO shown in (G). Three independent experiments were quantified by Image J and expressed as a percentage of the total SMO protein.
Figure 2(A) Biotinylation of SMO by SAR1B-BirA* (asterisk denotes the R118G mutation in BirA) in a proximity-dependent biotinylation assay. The cells were transfected with plasmids encoding SMO and SAR1B-BirA*-FLAG. After 48 h, cells were treated with different doses of biotin for 4 h. Cells were harvested and lysates were dialyzed to remove free biotin. Biotinylated proteins were pulled down by streptavidin beads and subjected to immunoblotting analysis. (B) The cells were treated with different doses of biotin for 24 h. Cells were harvested, lysed, and subjected to procedure as shown in Fig. 2A.(B) The cells were treated with different doses of biotin for 24 h. Cells were harvested, lysed, and subjected to procedure as shown in Fig. 2A.(C) The GDP-locked SAR1B(G37A)-BirA* failed to label SMO, while the GTP-locked SAR1B(H79G)-BirA* could efficiently biotinylate SMO. The cells were transfected with plasmids expressing SMO and indicated SAR1B-BirA*. After 48 h, cells were treated with 15 μM biotin for 4 h. Then experiments were carried out as described in Fig. 2A.(D) PTCH1 decreased SAR1B-BirA*-mediated biotinylation of SMO, but not LMAN1. The experiments were done similarly in Fig. 2A.(C) The GDP-locked SAR1B(G37A)-BirA* failed to label SMO, while the GTP-locked SAR1B(H79G)-BirA* could efficiently biotinylate SMO. The cells were transfected with plasmids expressing SMO and indicated SAR1B-BirA*. After 48 h, cells were treated with 15 μM biotin for 4 h. Then experiments were carried out as described in Fig. 2A. (D) PTCH1 decreased SAR1B-BirA*-mediated biotinylation of SMO, but not LMAN1. The experiments were done similarly in Fig. 2A. (E) The Shh increased the binding of SAR1B to SMO. After transfection for 24 h, cells were incubated with the ShhN conditioned medium for an additional 24 h. Then 15 μM biotin was added into the culture medium for 4 h. The cells were harvested and analyzed as described in Fig. 2A.
Figure 3(B) Treatment with glycosidase demonstrated that SMO (4A, in which RRTWCR was mutated to AATACA) was sensitive to Endo H. The experiments were done similarly in Fig. 2A. Black bracket indicates mature glycosylated form.(C) SAR1B-BirA*-mediated biotinylation of the SMO variants. The experiments were done similarly in Fig. 2A.(D) In vitro budding of SMO. Membranes were prepared and incubated in vitro in the presence of cytosol, ATP, GTP, and an ATP-regenerating system as described in experimental procedures. Then vesicle and membrane fractions were separated by centrifugation and subjected to immunoblotting analysis.(E) In vitro budding of the SMO variants. The experiments were done as same as in (D).(F) The ciliary localization of SMO variants. Smo-KO NIH3T3 cells were transfected with the EGFP fused SMO variants, incubated with serum starvation medium for 24 h to fully induce cilia formation, and treated with or without ShhN conditioned medium for 4 h. Cells were immunostained with the acetylated tubulin (red). Results shown are representative of three independent experiments. Scale bars: 5μm.(G) Quantitative assessment of the intensity of ciliary SMO in (F) by Image J. More than 45 cells were randomly selected and counted for each group.(H) Quantification of the percentage of cells with ciliary SMO. 80-90 cilia were analyzed in each group in each experiment.(I) Gli-luciferase reporter assay in Smo-KO NIH3T3 cells. The cells were transfected with plasmids encoding SMO or SMO variants, GLI-promoted firefly luciferase and renilla luciferase. After 24 h, cells were incubated with a medium containing different amounts of ShhN for another 24 h.
Figure 4(A) Shh increased cholesterylation of SMO. HEK293T cells were transfected, harvested, and analyzed(B) The SMO cholesterylation of Ptch1-KO NIH3T3 cells were increased comparing with WT cells.(C) The CP-modified SMO was mainly resistant to Endo H. The CP-modified SMO proteins were pulled down by streptavidin beads and digested with Endo H or PNGase F at 37 ℃. Then proteins were eluted with SDS-PAGE sample buffer and were subjected to immunoblotting analysis. Results shown are representative of two independent experiments.(D) Cholesterylation of SMO(4A) was inhibited by PTCH1 and increased by ShhN.(E) The CP-modified SMO(4A) was sensitive to Endo H treatment.(F) The levels of CP-modified WT SMO and SMO(4A) were compared. 1.39% of SMO(WT) pellet samples and 11.1% of SMO(4A) pellet samples were loaded. Results shown are representative of three independent experiments.(G) Quantification of CP-modified SMO shown in (F). Three independent experiments were quantified by Image J and expressed as a percentage of the total SMO.(H, I) The stimulative /inhibitory effect of Shh/PTCH1 on SMO and SAR1B interaction was compromised by D95E mutation. The experiments were done the same as Fig. 2E.
Figure 5ALOD4 inhibited the cholesterol modification of SMO Cells were treated with ALOD4 for 1 h, and then incubated with a medium containing ShhN and CP for 2 and 3 h. Cells were harvested and analyzedALOD4 inhibited the cholesterol modification of SMO(4A). Cells were treated with ALOD4 for 1 h In C, ShhN and CP added for 2 h. Cells were harvested and analyzed(D) Ciliary localization of endogenous SMO treated with or without ALOD4. Cells were treated with ALOD4 for 1 h, and then incubated with ShhN conditioned medium for 2 h. Results shown are representative of three independent experiments.(E) Quantitative assessment of the intensity of ciliary SMO in (D). More than 80 cells were randomly selected and counted for each group. Data are presented as median with interquartile.(F) Quantification of the percentage of cells with ciliary SMO in (D). Data are presented as mean ± SEM from three biological replicates (****p < 0.0001, one-way ANOVA with Dunnett's multiple comparison test). 90-100 cilia were analyzed in each group in each experiment.(G) Effect of ALOD4 on the expression of Gli1 was measured by qRT-PCR. The cells were treated with ALOD4 for 1 h, and then incubated with ShhN conditioned medium for 5 h.
Figure 6(A, B) GRAMD1B increased cholesterylation of SMO. HEK293T cells were co-transfected with the SMO or SMO (4A) and GRAMD1B protein expression plasmids for 24 h, and then incubated with a cholesterol depletion medium (DMEM supplemented with 5% lipoprotein-deficient serum, 1 μM lovastatin and 10 μM mevalonate) for 12 h, followed by 2 μg/mL of CP treatment. The cells were harvested and analyzed as Results shown are representative of two independent experiments.(C, D) GRAMD1B promoted SMO maturation. The expression plasmids of SMO or SMO(D95E) and GRAMD1B were transfected into SMO-KO HEK293T cells. After 12 h, cells were switched to a cholesterol depletion medium for 16 h and then added 50 μM MβCD-cholesterol for 8 h. Black bracket indicates mature glycosylated form.(E) Expression of Gli1 mRNAs measured by qRT-PCR in NIH3T3 cells stably expressing GRAMD1B. After incubating in serum starvation medium for 16 h, cells were depleted of cholesterol by treatment with 1.5% HPCD for 0.5 h and then incubated in serum starvation medium containing 1 μM lovastatin, 10 μM mevalonate and 10 μM MβCD-cholesterol, ShhN as indicated for 24 h.(F) Confocal images of NIH3T3 cells stably expressing mCherry-GRAMD1B. PM was labeled with wheat germ agglutinin (WGA)-CF®488A conjugate. Cells were incubated in a cholesterol depletion medium for 16 h and switched to the same medium containing 50 μM MβCD-cholesterol for 1 h. Cells were then treated with or without ShhN conditioned medium for another 2 h. Results shown are representative of three independent experiments.(G) The percentage of cells with GRAMD1B localization on PM. 60-70 cells were analyzed in each group in each experiment.
Figure 7(A) The cholesterol modification of endogenous SMO was decreased in NIH3T3 cells lacking Gramd1a, 1b, 1c, 2, and 3 (Gramd-5KO). The cells were incubated in a cholesterol depletion medium for 12 h, followed by 2 μg/mL of CP and ShhN for an additional 12h.(B) The glycosylation of endogenous SMO was decreased in Gramd-5KO NIH3T3 cells. The ShhN conditioned medium was applied for 24 h. Black bracket indicates mature glycosylated form.(C) The ciliary localization of endogenous SMO in WT or Gramd-5KO NIH3T3 cells. Cells were incubated in serum starvation medium for 24 h to fully induce cilia formation and then incubated with or without ShhN conditioned medium for 2 h. Results shown are representative of three independent experiments.(D) Quantitative assessment of the intensity of ciliary SMO in (C). More than 100 cells were randomly selected and counted for each group. Data are presented as median with interquartile.(E) Quantification of the percentage of cells with ciliary SMO. 86-100 cilia were analyzed in each group in each experiment.(F) The protein levels of Gli1 was significantly reduced in Gramd-5KO cells. The cells were incubated in a serum starvation medium with or without ShhN for 24 h. Results shown are representative of two independent experiments.(G) GLI-luciferase reporter assay in WT or Gramd-5KO NIH3T3 cells. Data are presented as mean ± SEM from three technical replicates (****p < 0.0001; ***p < 0.001; *p < 0.05, two-way ANOVA with Sidak's multiple comparison test).(H) The Gli1 mRNA levels were measured in WT, Gramd-5KO, Gramd-5KO overexpression GRAMD1A, 1B, 1C NIH3T3 cells by qRT-PCR after treatment with or without ShhN conditioned medium for 8 h. Data are expressed as mean ± SEM from three technical replicates (****p < 0.0001, two-way ANOVA with Tukey's multiple comparisons test).(I) The GRAMD inhibitor AI3d inhibited cholesterol modification of SMO in NIH3T3 cells. The cells were incubated in cholesterol depletion medium for 16 h and then treated with 3 μM AI3d for 6 h. Next, cells were incubated in the same medium containing ShhN and 2 μg/mL of CP for an additional 2 h.(J) The GRAMD inhibitor AI3d decreased the mRNA levels of Gli1 in NIH3T3 cells. Cells were incubated in serum starvation medium for 16 h, depleted of cholesterol by 1.5% HPCD for 0.5 h, and then treated with serum starvation medium containing 1 μM lovastatin, 10 μM mevalonate and 1 μM AI3d for 6 h. Next, cells were incubated in the same medium containing ShhN and 10 μM MβCD-cholesterol for an additional 16
Figure 1Nucleosomal array oligomers are globular.A Nucleosomal array oligomers were stained with DAPI and examined using FM (fluorescence microscopy) as described in the Materials and Methods section. Shown are representative images obtained in 4.5 mM and 10mM MgCl2.B Control FM images obtained in 0, 1 and 2.5 mM MgCl2.C Nucleosomal array oligomers were negatively stained and visualized by TEM as described under Materials and Methods. Shown in the left panels are representative images obtained in 4.5 mM, and 10 mM MgCl2. Shown in the right panels are images of the interior of the oligomers (white arrows, left panels) after cropping and re-scaling.
Figure 3A, B SAXS profiles of the nuclesomal arrays in 0 (TE), 1, 2.5 mM MgCl2 (A) and 5, 10 mM MgCl2 (B) are shown as plots of log(I × S2) vs. 1/S (I, intensity; S, scattering vector (1/nm)).
Figure 4A 601-nucleosomal arrays were incubated in 0.5, 5 mM MgCl2, 5 mM MgCl2 + MNase, and analyzed by the differential centrifugation assay to determine the fraction oligomeric. The amounts of DNA in the supernatant fraction were measured. Note that for the MNase-digested oligomers the supernatant fraction also includes the digested free linker DNA. Each value is the mean of three measurements and the error bars represent the standard deviation.B Verification of complete MNase digestion. DNA was purified from the nucleosomal arrays incubated in 5 mM MgCl2 or 5 mM MgCl2 + MNase, and then electrophoresed on agarose gel. The position of mono nucleosome is marked with a star symbol.C Nucleosomal array oligomers (left) or with MNase treatment (right) were stained with DAPI and examined using FM. Shown are representative images obtained. Note that the sizes of MNase-treated oligomers are much smaller than those of the control oligomers (left and Fig. 1A).
Figure 5A Oligomers assembled from H1-nucleosomal arrays were stained with DAPI and examined using FM. Shown are representative images obtained in 4 mM and 5 mM MgCl2.B Control FM images obtained in 0, 1 and 3 mM MgCl2.C H1-nucleosomal array oligomers were negatively stained and visualized by TEM. Shown in the left panel is a representative image obtained in 4 mM MgCl2. Shown in the right panel is an image of the interior of the oligomer (white arrow, left panel) after cropping and re-scaling.
Figure 7A, B SAXS profiles of the H1-nuclesomal arrays in 0 (TE), 1, 2.5 mM MgCl2 (A) and 5, 10 mM MgCl2 (B) are shown as plots of log(I × S2) vs. 1/S (I, intensity; S, scattering vector (1/nm)).C, D SAXS profiles of the native chicken chromatin in 0 (TE), 0.5, 1 mM MgCl2 (C) and 2.5, 5 mM MgCl2 (D) are shown as plots of log(I × S2) vs. 1/S (I, intensity; S, scattering vector (1/nm)).
Figure 8A FMimages of chromatin structure in the nuclei with 0 mM (left), 1 mM (center) and 5 mM MgCl2 (right). Insets show the intensity line profiles between the two marked arrow heads in the images.B SAXS profiles of the isolated HeLa nuclei. SAXS profiles of the nuclei in 0 mM (left), 1 mM (center) and 5 mM MgCl2 (right) are shown in blue. For comparison, the scattering curves of H1-arrays from Figs. 7A and B were overlaid as red lines (left, 0 mM; center and right, 10 mM MgCl2).