EMBO/SourceData huggingface dataset:
Figure 4A Protein O-glucosyltransferase activity of wild-type (WT) or D233E mutant POGLUT1 protein toward human factor IX EGF repeat (hFIX-EGF). Wild-type shows higher O-glucosyltransferase activity than D233E, and this activity is dependent on the concentration of the acceptor substrate hFIX-EGF repeat (left) and on the concentration of donor substrate UDP-glucose (UDP-Glc) (right). Values indicate mean ± SEM from three independent assays.B O-glucosyltransferase activity towards five different single EGF repeats from mouse Notch1. Wild-type POGLUT1 shows higher activity toward all EGF repeats tested than POGLUT1D233E. The Y-axis shows the normalized activity relative to wild-type POGLUT1. EGF repeats were at 10 μM. Values indicate mean ± SEM from three independent assays.C Elution profiles of the POGLUT1 reaction products on reverse phase HPLC. hFIX-EGF repeat was incubated with wild-type or D233E mutant POGLUT1 and donor substrate, UDP-Glc or UDP-xylose (UDP-Xyl), at 37ºC overnight. Values on top of the peaks indicate the measured masses. Addition of Glc (162 Da) or xylose (132 Da) to hFIX-EGF (5696.2 Da) by wild-type POGLUT1 caused a shift to an earlier retention time (left). Similarly, the products exhibited a similar shift after incubation with POGLUT1D233E (right). These results indicate that POGLUT1D233E can add a single glucose or xylose to hFIX-EGF repeats and thus has residual enzymatic activity.
Figure 5A Western blot of muscle homogenates shows reduced expression of Notch1 intracellular domain (NICD) in patients.B-C qRT-PCR on RNA extracted from skeletal-muscle shows that expression of HES1 (B) and PAX7 (C) was significantly lower in D233E patients compared to healthy controls. Mean ± SEM, Student´s t-test (B) and Mann-Whitney U test (C).D PAX7+ cells in skeletal muscle sections, demonstrating that satellite cells are less abundant in D233E patients than in controls (n = 3 muscles with 10-15 fields analyzed per muscle). Mean ± SEM; Mann-Whitney U test; Scale bar, 50 μm.
Figure 7A-F Proliferation assays examined proliferating (PAX7+MyoD+, arrows), self-renewing (PAX7+ MyoD−, open arrows), and differentiating (PAX7− MyoD+, arrowheads) cells from D233E patients (n = 2), healthy controls (n = 3) and disease controls (n = 3) at 1, 4, and 8 days growing in proliferation medium. (A) shows representative images from day 8. The number of patientmyoblasts is lower than that of controls at all three time points, indicating a slower proliferation rate in patientmyoblasts (B), and accordingly, the percentage of proliferating cells (C) is smaller in the patient. (D) The percentage of self-renewing cells is small in patient´s culture, reflecting a poor capacity for maintaining the pool of quiescent SCs. In addition, the percentage of PAX7+ cells (E) is smaller in patient´s culture, similarly to what was found in adult D233E muscle (shown in Fig 5D). (F) The percentage of differentiating cells is higher in the patient. We examine proliferation capturing 7-12 randomly fields per day and condition (mean ± SEM is shown; Kruskal-Wallis with Dunn´s multiple comparisons test; Scale bar, 50 µm).G-I When myoblasts started to be confluent, the proliferation medium was replaced with differentiation medium, and the myoblasts started to fuse yielding myotubes, which were analyzed after four days of differentiation. (H) The fusion index, which measures the percentage of nuclei in myotubes with respect to the total number of nuclei in myogenic cells, was higher in D233E cultures than in controls. (I) Besides, myogenin showed increased expression in D233E myoblast cultures compared to controls. The data support that differentiation process is facilitated in patient´s muscle. Data was collected from 3-10 randomly chosen areas per condition (mean ± SEM is shown; Kruskal-Wallis with Dunn´s multiple comparisons test (H) and One-way Anova with Bonferroni´s multiple comparisons test (I); Scale bar, 50 µm).
Figure 8A-C We overexpressed GFP-tagged NICD in immortalized primary myoblasts to rescue the features displayed by immortalized D233E myoblasts. (B) We analyzed the proliferation at 1, 3 and 5 days, and proliferation rate in patient-LV-NICD-GFP reached the level observed in control-LV-GFP, which were higher than in patient-LV-GFP. (C) However, the percentage of PAX7+cells in patient-LV-NICD-GFP showed the same reduced value as in patient-LV-GFP, which were significantly lower than in control-LV-GFP. The majority of control myoblasts were proliferating cells (PAX7+ MyoD+, arrows), with no quiescent cells and few differentiating cells detected. Data were collected from n = 2 independent assays (5-8 images per condition). Mean ± SEM is shown; One-way Anova with Tukey multiple comparisions test (B) and Kruskal-Wallis with Dunn´s multiple comparisons test (C); Scale bar, 50 µm).D-F As previously described in patient's primary myoblasts, patient-LV-GFPmyoblasts showed a striking facilitated differentiation compared to control-LV-GFP-myoblasts. This phenotype fully disappeared in patient-LV-GFP-NICD myoblasts, as quantification of the fusion index (E), and myogenin expression (F) demonstrated. The data support a pathogenic role for Notch inhibition on the altered differentiation in our patients. Data were collected from n = 3 independent assays (13-17 images per condition). Mean ± SEM is shown; Kruskal-Wallis with Dunn´s multiple comparisons test; Scale bar, 50 µm).
Figure 9A Immortalized primary myoblasts from a healthy control showed a progressive pattern of α-dystroglycan glycosylation during five days of differentiation (D0-D5), as has been previously described by Goddeeris et al. Immortalized primary myoblasts from patients displayed an irregular pattern of glycosylation, with a final level of glycosylated α-dystroglycan that was lower than control.B α-dystroglycan glycosylation of infected immortalized myoblasts from patient-LV-NICD-GFP at differentiation day 5 (D5) showed a striking reduction, in line with the strong inhibition of myotubes formation and differentiation induced by NICD overexpression. α-dystroglycan in myoblasts from patient-LV-GFP showed a reduction of glycosylation compared to control-LV-GFP at D5, similar to the results obtained in the adult muscle from patients (Fig. 2).C-D C2C12 myogenic cells showed a reduced level of glycosylated α-dystroglycan when the Notch signaling inhibitor DAPT or LY3039478 was added to the differentiation medium. This indicates that reducing Notch signaling can affect α-dystroglycan glycosylation in wild-type C2C12 myoblasts cells, which do not harbor any known mutations in α-dystroglycan glycosyltransferases or Poglut1.E-F qRT-PCR experiments show that upon DAPT or LY3039478 treatment, a remarkable decrease in Hes1 mRNA is induced in C2C12 cells during differentiation.
Figure 1Relative expression of Rab39a in siRNA-treated cells after 48 hours of knockdown. Rab39a expression in I-Ab or Rab39a siRNA-treated cells was normalized to expression in cells treated with control β2m siRNA. Error bars show SD between three independent experiments. * p < 0.05 using two-way Student's t-test.XPT of siRNA treated DC3.2R cells after 48 hours of knockdown. Treated cells were fed with the indicated amounts of Ova-Fe The cells were then exposed to RF33.70-Luc Reporter CD8 T cells overnight. RLU indicates relative luminescence units produced by reporter T cell stimulation. Error bars show SD of >3 replicate wells. * p < 0.05 vs control I-Ab using two-way ANOVA. Representative plot of 3 independent experiments.XPT of siRNA treated DC3.2R cells after 48 hours of knockdown. Treated cells were fed with the indicated amounts of Ova-latex The cells were then exposed to RF33.70-Luc Reporter CD8 T cells overnight. RLU indicates relative luminescence units produced by reporter T cell stimulation. Error bars show SD of >3 replicate wells. * p < 0.05 vs control I-Ab using two-way ANOVA. Representative plot of 3 independent experiments.XPT of siRNA treated DC3.2R cells after 48 hours of knockdown. Treated cells were fed with the indicated amounts of unconjugated soluble Ova The cells were then exposed to RF33.70-Luc Reporter CD8 T cells overnight. RLU indicates relative luminescence units produced by reporter T cell stimulation. Error bars show SD of >3 replicate wells. * p < 0.05 vs control I-Ab using two-way ANOVA. Representative plot of 3 independent experiments.DC3.2-Rab39a cells (Rab39a KO with dox-inducible Rab39a) were incubated overnight with or without 1 µg/ml dox to induce Rab39a expression. 1x105 Cells were then fed with Ova-Fe and exposed to reporter T cells as in (B). Error bars show SD of duplicate wells. * p < 0.05 using two-way ANOVA. Representative plot of 3 independent experiments.
Figure 2MHC-II presentation of siRNA treated DC3.2R cells after 48 hours of knockdown. Treated cells were fed with the indicated amounts of Ova-Fe. The cells were then exposed to MF2.2D9-Luc Reporter CD4 T cells overnight. Error bars show SD of >3 replicate wells. * p < 0.05 vs negative control β2m using two-way ANOVA. None of the bead concentrations are p < 0.05 for Rab39a siRNA vs β2m. Representative plot of 3 independent experimentsDC3.2-Rab39a cells (Rab39a KO with dox-inducible Rab39a) were incubated overnight with or without 1 µg/ml dox to induce Rab39a expression. 1x105 cells were then fed with Ova-Fe and exposed to reporter T cells as in (A). Error bars show SD of duplicate wells. None of the bead concentrations are p < 0.05 for Rab39a siRNA vs β2m using two-way ANOVA. Representative plot of 3 independent experimentsMHC-I Presentation of SIINFEKL-H2-Kb complexes on siRNA treated DC3.2 NS-Ova (C) or DC3.2 UbS8L (D) cells. 48 hours after siRNA transfection, the indicated amounts of dox was added to the cells to induce Ova expression. After 2 hours at 37oC, RF33.70-Luc CD8 T cells were added along with Brefeldin A (Golgiplug) to a final concentration of 1:1000. The cells were incubated overnight for reporter T cell luciferase expression. Error bars show SD of >3 replicate wells. * p < 0.05 vs negative control I-Ab using two-way ANOVA. None of the dox concentrations are p < 0.05 for Rab39a siRNA vs I-Ab. Representative plot of 3 independent experimentsFlow cytometric analysis of surface H2-Kb and I-Ab levels of siRNA treated DC3.2R cells. Shown are results after 48 hours of knockdown. Representative plot of 3 independent experiments
Figure 3Phagocytosis assay after 48 hours of siRNA knockdown. DC3.2R cells treated with the indicated siRNAs were incubated on ice for 30 minutes with 4 beads per cell of Alexa Fluor 647 conjugated beads. The mixture was then placed in media at 37oC for 1 hour. Cells were harvested and incubated on ice with 1 mg/ml of Trypan Blue to quench uneaten beads before analysis through flow cytometry. As a control, some cells were incubated with 10 µM Cytochalasin D during the feeding period. Shown are percentages of cells that have taken up beads. Representative plot of two independent experiments.Rab39a was induced in DC3.2-Rab39a cells (Rab39a KO with dox-inducible Rab39a) via overnight incubation with 1µg / ml dox. KO and rescued cells were then harvested and assayed as in (A) for phagocytosis. Representative plot of two independent experiments.DC3.2-Rab39a cells were induced to express Rab39a overnight. Cells on coverslips were washed, fixed and stained according to the listed protocol and antibodies. Green = Rab39a (HA tag), Magenta = Lamp2. Arrows highlight punctate structures with colocalization. Scale bar = 10 µm. Representative image of two independent experiments.DC3.2 Rab39a KO cells were transduced with dox inducible mcherry-tagged Rab39a. Cells were plated in 35 mm glass bottom dishes and induced with 1 µg/ml dox. The next day, 1 µm latex beads conjugated with Alexa 488-NHS (1 bead/cell) were added. After 2 hours at 37oC, cells were imaged under a Leica TCS SP5 confocal microscope. Green = Alexa 488 labeled beads. Magenta = mcherry-Rab39a. Arrows highlight internalized beads surrounded by Rab39a. Scale bar = 10 µm. Representative image of two independent experiments.5x105 of DC3.2-Rab39a cells were induced to express Rab39a overnight with 1 µg/ml dox in a 6 well plate. Cells were fed at 1 bead/cell of biotinylated-6µm magnetic beads for the indicated lengths of time. Magnetic-bead-phagosomes were isolated using the listed protocol. Phagosomes were washed and stained for Rab39a (HA-tag). Representative data for 3 independent experiments.1.25 x 105 of DC3.2-Rab39a cells were incubated in a 12 well plate overnight ± dox (1µg/ml) to induce Rab39a. Cells were fed at 4 beads/cell of biotinylated-ova-6µm-magnetic-beads for 3 hours with or without 1:1000 BFA (golgiplug, BD). Phagosomes were isolated using the listed protocol. Isolated phagosomes were washed, permeabilized and stained. Shown are histograms of indicated stains as well as % of Rab39a positive phagosomes. Representative plot of two independent experiments.
Figure 4XPT of siRNA treated DC3.2R cells after 48 hours of knockdown. Treated cells were fed with the indicated amounts of C8L peptid conjugated to iron oxide beads via a disulfide bond. The cells were then exposed to RF33.70-Luc Reporter CD8 T cells overnight. Error bars show SD of >3 replicate wells. * p < 0.05 for siRNA vs control I-Ab using two-way ANOVA. Representative plot of 3 independent experimentsXPT of siRNA treated DC3.2R cells after 48 hours of knockdown. Treated cells were fed with the indicated amounts o Ova (B) conjugated to iron oxide beads via a disulfide bond. The cells were then exposed to RF33.70-Luc Reporter CD8 T cells overnight. Error bars show SD of >3 replicate wells. * p < 0.05 for siRNA vs control I-Ab using two-way ANOVA. Representative plot of 3 independent experimentsDC3.2-Rab39a cells (Rab39a KO with dox-inducible Rab39a) were incubated overnight with or without 1 µg/ml dox to induce Rab39a expression. 1x105 cells were then fed with C8L peptide beads and exposed to reporter T cells as in (A). Error bars show SD of duplicate wells. * p < 0.05 between no dox and + dox using two-way ANOVA. Representative plot of 3 independent experimentsSame as in (A) but cells were fed with 8 µg of A9M peptide bead and exposed to 12.64-Luc Reporter T cells. Experiments were combined by normalizing RLU values to the average of the negative control I-Ab. Error bars show SD of 3 independent experiments. * p < 0.05 for Rab39a or β2m siRNA vs negative control I-Ab using ANOVA
Figure 5DC3.2-Rab39a-H2-Ld cells (Rab39a KO with dox-inducible Rab39a) were incubated with or without 1 µg/ml dox overnight to induce Rab39a expression. 1x106 cells were fed at 4 beads/cell of biotinylated-magnetic-beads for 4 hours. Magnetic bead phagosomes were isolated using the listed protocol. Phagosomes were washed, fixed, permeabilized and stained for Open (64-3-7) and Closed (30-5-7s) forms of H2-Ld. Representative histograms shown in (B). The background fluorescence of unstained beads was subtracted from the resulting phagosome gMFI and the fold change of open or closed H2-Ld (dox/no dox) was calculated. Three independent experiments were combined for analysis and error bars show the SD between experiments. Open H2-Ld, but not Closed H2-Ld was statistically significant (p<0.05) between KO and rescued cells using two-tailed ratio-paired Student's t-test.DC3.2-Rab39a-H2-Ld cells (Rab39a KO with dox-inducible Rab39a) were incubated with or without 1 µg/ml dox overnight to induce Rab39a expression. 1x106 cells were fed at 4 beads/cell of biotinylated-magnetic-beads for 4 hours. Magnetic bead phagosomes were isolated using the listed protocol. Phagosomes were washed, fixed, permeabilized and stained for Open (64-3-7) and Closed (30-5-7s) forms of H2-Ld. H2-Ld cell surface levels of KO and induced cells as in (A).Phagosomes from KO and induced cells were isolated as in (A). Permeabilized, unfixed phagosomes were incubated with 10 µM of the indicated peptides for 3 hours at 25oC in Perm buffer. Phagosomes were then washed and stained for H2-Ld. Shown are histograms of indicated stains.Phagosomes from KO and induced cells were isolated as in (A). Permeabilized, unfixed phagosomes were incubated with 10 µM of the indicated peptides for 3 hours at 25oC in Perm buffer. Phagosomes were then washed and stained for H2-Ld. Shown are histograms of indicated stains. Flow cytometry plots of (D).Analysis of phagosomes shown in (D) and (E). The background fluorescence of unstained beads was subtracted from the resulting phagosome gMFI and the fold change of pulsed / unpulsed phagosomes was calculated.DC3.2 Rab39a-H2-Ld cells were incubated with or without 1 µg/ml dox overnight to induce Rab39a expression. 1x106 cells were fed at 4 beads/cell of biotinylated-Ova-magnetic-beads for 4 hours in the presence or absence of BFA. Isolated phagosomes were stained for H2-Ld. Representative of two independent experiments.
Figure 7Rab39a expression in splenocyte subsets was measured using an FDG assay. Shown are relative FDG fluorescence of Rab39a KO cells/WT background. Summary of two independent experiments.Splenic DCs were expanded in Rab39a KO and WT mice by injection of B16-Flt3L tumor. 10 days post tumor implantation, DCIR2+ (Cd8α-) or XCR1+ (Cd8α+) dendritic cells were isolated from spleens via magnetic positive selection. 5 x 104 cells were plated in a 96 well plate and incubated with the indicated amounts of Ova-Fe and 1:1 of Reporter CD8 or CD4 T-cells overnight before measuring luciferase activity. Error bars indicate SD of 2 replicate wells. Shown are representative graphs of 3 independent experiments. * p < 0.05 using two-way ANOVA.CD11b+ CD11c+ dendritic cells were enriched from WT or Rab39a KO spleens via magnetic negative selection. Cells were fed with 3 µm biotin-ova-magnetic beads for 4 hours. Phagosomes were extracted, permeabilized and stained for the indicated proteins. For ROS measurements, phagocytosis was performed with 5 µM CellROX and the phagosomes were not permeabilized. For analysis, the background fluorescence of unstained beads was subtracted from the resulting phagosome gMFI and the fold change of target (dox/no dox) was calculated. Shown are three independent experiments combined. Error bars show SD between experiments. p values were calculated using two-tailed ratio-paired Student's t-test.CD11b+ CD11c+ dendritic cells were enriched from WT or Rab39a KO spleens via magnetic negative selection. Cells were fed with 3 µm magnetic beads conjugated to pHrodo. After 4 hours, cells were harvested for flow cytometry to measure fluorescence of eaten beads due to phagosomal pH. For analysis, the background fluorescence of unstained beads was subtracted from the resulting gMFI and the fold change (dox/no dox) was calculated. Shown are three independent experiments with error bars indicating the SD. p values were calculated using two-tailed ratio-paired Student's t-test.CD11b+ CD11c+ dendritic cells were enriched from WT or Rab39a KO spleens via magnetic negative selection. Cells were fed with 3 µm magnetic beads conjugated to Alexa fluor dye. After 4 hours, cells were harvested and resuspended in 1 mg/ml Trypan blue to quench fluorescence of uneaten beads. Cells were run for flow cytometry to measure phagocytosis. The ratio of KO cells with beads / WT cells with beads was then obtained. Graphs show three independent experiments and p values were calculated using two-tailed ratio-paired Student's t-test. Error bars show SD between experiments.Rab39a KO and WT mice were injected intravenously with 1 x 105 A20-Ova cells. The next day, CFSE labeled OTI-splenocytes were injected i.v.. 3 days post OT-I transfer, spleens were harvested and assayed for OT-I proliferation. Three independent experiments (WT vs KO) were performed. To combine the data, the OT-I proliferation in each individual mouse was normalized to the average proliferation of the WT controls in that experiment. Error bars show SD between individual mice and p value was derived from two-tailed student's t-test. n = 14 (WT) or 9 (KO).
Figure 1B HSATIII ASO-mediated depletion of nSBs. Thermal stress-exposed HeLa cells (42°C for 2 h and recovery for 1 h at 37°C) were visualized by HSATIII-FISH and immunofluorescence using an anti-SAFB antibody or anti-HNRNPM antibody. The nuclei were stained with DAPI. Scale bar: 10 μm.C qRT-PCR-validation of HSATIII knockdown. The graph shows the qRT-PCR level of HSATIII RNAs in control and HSATIII knockdown cells under three conditions: 37°C, 42°C for 2 h, and thermal stress followed by recovery at 37°C for 1 h (Recovery). Expression levels were calculated as ratios to GAPDH mRNA and were normalized to the levels in control cells under thermal stress conditions (42°C for 2 h). Data are shown as the mean±SD (n=3). HSATIII RNAs ratios (%) are indicated.D MA-plot (log2 fold-change over the average expression level) of all detected introns in HSATIII KD and control cells (n=3). The introns with significant changes in their expression levels (adjusted p-value < 0.01) are shown as green dots. Among these introns, up-regulated (log2 fold-change > 1) and down-regulated (log2 fold-change < -1) introns are shown with magenta and light blue dots, respectively. Genes and introns that were experimentally validated in subsequent experiments are indicated as gene symbol-i (intron) #. Total numbers of introns and genes utilized were 144769 and 32623, respectively.Examples of RNA-seq read maps of HSATIII target RNAs. Affected introns and exons are indicated by blue (down-regulated upon HSATIII knockdown)G Examples of RNA-seq read maps of HSATIII target RNAs. Affected introns and exons are indicated by blue (down-regulated upon HSATIII knockdown) and magenta (up-regulated) boxes.
Figure 2Validation of HSATIII target introns by qRT-PCR. The graphs show the relative amounts of the intron-retaining (IR) (upper) and spliced (lower) forms in control and HSATIII knockdown cells under three conditions: 37°C (normal), 42°C for 2 h (thermal stress), and thermal stress followed by recovery at 37°C for 1 h. Expression levels were calculated as the ratio of each RNA to GAPDH mRNA and were normalized to the levels in control cells under normal conditions (37°C). Data are shown as the mean±SD (n=3); *p<0.05 (Sidak's multiple comparison test).B Nuclear localization of the intron-retaining RNAs. The relative amounts of intron-retaining RNAs in the nuclear and cytoplasmic fractions were quantified by qRT-PCR and are represented as the ratio (% of the total). GAPDH mRNA and U1 snRNA were used as cytoplasmic and nuclear controls, respectively. Data are shown as the mean±SD (n=3).D, E The levels of HSATIII target introns in newly synthesized RNAs within 1 h after thermal stress removal, as determined by qRT-PCR. The graphs show the changes in the expression levels of the intron-retaining (IR) (D) and spliced (E) forms. Expression levels were calculated as the ratio of each RNA to GAPDH mRNA and were normalized to the level in the control cells. Data are shown as the mean±SD (n=3); *p<0.05 (multiple t-test modified by Holm-Sidak's method).