EMBO/SourceData huggingface dataset:
Figure 3Depicted are the fractions of SVs without filaments, ribbon-attached SVs (Ri.), interconnected SVs (In.) and SVs with Ri. + In. per ribbon, at (A) the distal (Ds.) and (B) the proximal (Pr.) part of the ribbon. Data are represented as mean ± SEM of wild-type and OtofPga/Pga IHCs under inhib, rest and stim. (A) Upon stimulation, in the Ds. part at wild-type, the fraction of SVs without filaments reduces, but of SVs with Ri. + In. increases significantly. At OtofPga/Pga IHCs the fraction of SVs without filaments is reduced when comparing stim vs. inhib. The fraction of interconnected SVs increases with stimulation compared to inhibition and rest. In the mutant (inhib), the fraction of interconnected SVs decreases compared to wild-type (inhib), and Ri. + In. SVs reduce vs. wild-type (stim). (B) The fraction of SVs without filaments increased at inhibited OtofPga/Pga synapses. The red dotted lines in (A) and (B) represent the mean fraction of RA-SVs/ribbon part of resting wild-type for each defined sub-pool.
Figure 4Representative wild-type virtual section under rest depicts SVs with r-attached fil (Ra.fil., red arrowheads) and one interconnector (Intercon., purple arrowhead), around the ribbon (R). Magnification 12,000x; scale bar, 40 nm. Example 3D reconstruction of the RA-SVs with filaments (green) in resting wild-type. Larger average length is found for ribbon-attached filaments (Ra.fil., red) vs. SV interconnectors (Intercon., purple). For clear visualization, the ribbon (R) is transparent and the same SV pair is shown in a front (A'), side (A'') and top view (A'''). Scale bar, 50 nm.Increased mean length of ribbon-attached filaments vs. SV interconnectors in all conditions for both genotypes. The red dotted lines represent the mean RA-filament length in resting wild-type for each sub-pool.The cumulative probability distribution of RA-SVs plotted against the individual filament length. The graph illustrates shorter filaments in wild-type and OtofPga/Pga ribbon synapses upon stimulation.Decreased mean filament length upon stimulation in wild-type and OtofPga/Pga ribbon synapses. Resting OtofPga/Pga exhibit the shortest mean filament length. The red dotted lines represent the mean RA-filament length in resting wild-type for each sub-pool.
Figure 5Representative tomographic virtual sections from resting wild-type. Five different types of MP-SVs are observed that we classify as sub-pools: non-tethered SVs (A',A''; yellow), single presynaptic density-attached SVs (B',B''; Pd.a, orange, pink arrowhead) or single m-attached SVs (C',C''; Ma., orange, orange arrowhead), or multiple-tethered SVs (D',D''; orange, brown arrowheads) and docked SVs (E',E''; light orange). Ribbon (R), presynaptic density (PD, pink) and AZ-membrane (blue). For clarity, a simplified illustration is provided for each sub-pool. Magnification: 12,000x; scale bar, 40 nm. The graph is showing the percentage of the MP sub-pools shown in A-E of all MP-SVs at inhibitory, resting and stimulatory wild-type synapses.
Figure 6Depicts the fraction of non-tethered and single-tethered MP-SVs per ribbon. Data are presented in mean ± SEM. The fraction of non-tethered SVs reduces in wild-type and OtofPga/Pga after stimulation and the fraction of single membrane-attached tethers increases in wild-type upon stimulation. In resting wild-type, most single-tethered SVs are attached to the presynaptic density.
Figure 7Example tomographic virtual sections from inhibitory: wild-type (A) and OtofPga/Pga (B); stimulatory: wild-type (C) and OtofPga/Pga (D). Tethered SVs are highlighted in orange with orange tether(s); single-tethers (with orange arrowhead) and multiple-tethers (with brown arrowhead). The number of tethers per SV is indicated. Magnification: 12,000x; scale bar, 40 nm. Virtual sections from inhibitory: wild-type (E) and OtofPga/Pga (F); stimulatory: wild-type (G) and OtofPga/Pga (H). Docked SVs at the AZ-membrane (blue line) are highlighted (orange asterisk). Some docked SVs are localized close to the presynaptic density (PD, pink outline), anchoring the ribbon (R). Magnification: 12,000x; scale bar, 100 nm.Percentage of multiple-tethered MP-SVs per ribbon of the total MP-SV pool show more multiple-tethered SVs in OtofPga/Pga IHCs. Percentage of docked MP-SVs per ribbon of the total MP-pool. The number of docked SVs is significantly increased at OtofPga/Pga inhibited and specifically at stimulated AZs. P-values for (I) and (J) are calculated by Fisher's exact Chi-square test, wild-type: inhib, n = 102 SVs; rest, n = 82 SVs; stim, n = 99 SVs; OtofPga/Pga: inhib, n = 123 SVs; rest, n = 96 SVs; stim, n = 111 SVs; ns p > 0.05, ** p < 0.01, *** p < 0.001, **** p < 0.0001Bar-plots show the distance of multiple-tethered (O) and docked (P) SVs from presynaptic density (PD), 0-100 nm: MP-SV pool (dark blue); 100-500 nm: peripheral SV pool (light blue). Upon stimulation, multiple-tethered and docked SVs are localized significantly closer to the PD in OtofPga/Pga. P-values for (O) and (P) are calculated by Wilcoxon Rank test, * p < 0.05, *** p < 0.001, ns p > 0.05 and Ø inconclusive statistics because occurrence of docked SVs in wild-type resting condition is extremely rare. Multiple-tethered SVs, wild-type: inhib, n = 3 SVs; rest, n = 13 SVs; stim, n = 3 SVs; OtofPga/Pga: inhib, n = 21 SVs; rest, n = 34 SVs; stim, n = 16 SVs; docked SVs, wild-type: inhib, n = 2 SVs; rest, n = 1 SVs; stim, n = 7 SVs; OtofPga/Pga: inhib, n = 20 SVs; rest, n = 4 SVs; stim, n = 18 SVs.
Figure 8Example virtual sections depict SVs with single membrane- (orange arrowhead) and presynaptic density (pink arrowhead) -attached tethers in resting wild-type. Magnification 12,000x; scale bar, 40 nm. 3D reconstructions of same tethered SVs (orange) as shown in (A) and (B); membrane-attached (A', yellow tether) and presynaptic density (PD) -attached (B', pink tether). Individual tether lengths are depicted. For clarity, ribbon (R) and AZ-membrane are shown in transparent. Scale bar, 20 nm.The graph depicts the mean length of single membrane-, presynaptic density-attached and multiple-tethers. Data are presented as mean ± SEM. Stimulated OtofPga/Pga synapses exhibit a shorter average tether length compared to stimulated wild-type.The cumulative probability distribution of MP-SVs plotted against the tether length. The red dotted lines represent the mean MP tether length in resting wild-type for each sub-pool.Total mean tether length in the MP-SV pool. Data are presented as mean ± SEM. Longer tethers are present upon stimulation in wild-type. Resting OtofPga/Pga ribbon synapses harbor the longest tethers, and tether where shorter at stimulated OtofPga/Pga synapses compared to wild-type. The red dotted lines represent the mean MP tether length in resting wild-type for each sub-pool.
Figure 1(a) Expression of H2B-mCherry under control of the CLV3 promoter in 14-d-old seedlings. Whole-mount immunostaining using α-mCherry antibodies and laser scanning microscopy (scale bar 10 μm).(c) A representative example for enrichment of CLV3 transcript in mCherry-positive nuclei determined by qRT-PCR and normalized to wt (N = 1).
Figure 2(a) Expression of CLV3, mCherry, TEL2, PAN, and the meristem marker genes STM and KNAT1. Asterisks indicate timepoints of significantly different expression (Wald test, Benjamini & Hochberg corrected, q<0.05) between stem and non-stem cells for each time point (N = 2). + = stem cell nuclei; - = non-stem cell nuclei, E = nuclei from embryos, D7/14/35 = nuclei from 7/14/35 day-old plants, S14 = nuclei from 14 d-old above-ground seedlings.(c) Number of DEGs between stem and non-stem cells at each timepoint. The banded portion of the bars indicates the number of transcription factor genes (also in parenthesis).
Figure 3(b) Expression of individual significantly up-regulated genes marked with # in (a). Asterisks indicate timepoints of significantly different expression (Wald test, Benjamini & Hochberg corrected, q<0.05) between stem and non-stem cells for each time point (N = 2).+ = stem cells; - = non-stem cells, E = nuclei from embryos, D7/14/35 = nuclei from 7/14/35 day-old plants, S14 = nuclei from 14 d-old above-ground seedlings.
Figure 4(a) Box plot summarizing differential expression of unambiguously mapped individual TEs, compared with all protein-coding genes, or housekeeping genes. Box plots outline the interquartile range (IQR) with the median and whiskers +/- 1.5 IQR . For all p-values, see also Appendix Table EV6. ** indicate a p-value smaller than 1.01e-11 (two sided non paired Wilcoxon rank sum test).
Figure 5(a) Increased expression of TEs in stem cells of D7 seedlings according to qRT-PCR. Box plots outline the interquartile range (IQR) with the median and whiskers +/- 1.5 IQR. N = 2 (ATLANTYS3, ATCOPIA39, ATCOPIA49, ATCOPIA29, ATGP1-1), N = 3 (VANDAL6, ATGP2, ATGP1-2, ATLINE1, ATGP1-3), N = 4 (ATHILA6A, ATCOPIA83), N = 5 (VANDAL12, ATHILA3, ATCOPIA22), and N = 6 for CLAVATA. *p<0.01, **p<0.001 (t-test).(b) Heatmap of TE expression in several silencing mutants determined by qRT-PCR relative to a housekeeping gene. To be able to display data in log-scale also for samples with zero expression, a value of 1.0e-6 (factor 10 smaller than the smallest value) was added to all values. Data for nuclei and CLV3::H2BmCherry are the same as in (a). For seedling samples, N = 2 (ATCOPIA49, ATHILA3), N = 3 (ATCOPIA39, VANDAL6, ATGP2, ATLINE1, ATCOPIA29, ATGP1-1), and N = 4 (ATLANTYS3, VANDAL12, ATGP1-2, ATHILA6A).
Figure 6(a) CG, CHG, and CHH methylation at chromosome 3 in stem and non-stem cells. The inset for CHG methylation shows a magnification of the pericentromeric region.
Figure 7(a) DNA methylation in % at CHG (left) and CHH (right) sites in TE with increased expression at D7, compared between developmental stages (D7/14/35 = 7/14/35 day-old plants) and nuclei of stem (+) and non-stem (-) cells.(b) Genomic location of the TEs (blue) from (a) on the five chromosomes. Dark grey bars indicate the location of centromeres and blue lines indicate global TE density.
Figure 8(a) DNA methylation differences between stem and non-stem cells and their enrichment within DMRs of different epigenetic mutants using permutation tests (data from Stroud, Greenberg, Feng, Bernatavichute and Jacobsen 2013). Mutants are in alphabetical order according to the gene acronym. Red indicates an enrichment of methylated DNA in the respective context and blue a depletion.
Figure 1(K TUNEL staining of testis sections from WT and KO mice at four months of age (K) White dotted line indicates the outline of testis tubules.L) TUNEL staining of testis sections from WT and KO mice at four months of age with apoptotic cell number per tubule (L). n=3 in (L).
Figure 3(A) Immunostaining of SYCP3 and γH2AX in sections from adult WT mice. Arrow and arrowhead indicate diffuse and dot-like γH2AX staining, respectively. White dotted line indicates the outline of testis tubules. (B) Proportion of tubules of γH2AX expression patterns. At least 100 tubules of each mouse were counted. n=4 for WT and n=5 for KO. (C) Average number of spermatocytes with γH2AX expression patterns per tubule. At least 50 tubules of each mouse were counted. n=3.(D-H) Representative nuclear spreads of WT and KO spermatocytes at leptonema (D), zygonema (E), early pachynema (F), late pachynema (G) and diplonema (H). Spermatocytes were immunostained for SYCP3, γH2AX, and H1t. Magnified views are indicated by dashed areas. Schematic representation shows homolog characteristic revealed by SYCP3 signals at different backgrounds and stages. Arrowheads indicate bivalent stretches lacking SYCP3 signals in KO. (I) Proportion statistics of spermatocytes with discontinuous SYCP3 signals. At least 200 cells of each mouse were counted. n=3 for WT and n=4 for KO. (J) Meiotic stage frequencies in (D-H). At least 200 cells of each mouse were counted. n=3.
Figure 4(C) Nuclear-spread spermatocytes from WT and KO mice were immunostained for SYCP3 and MLH1. Representative images of pachynema are shown. Magnified views are indicated by dashed areas. (D) Number of bivalents without an MLH1 focus per pachytene spermatocyte in (C). n=3 mice. Nor, normal pachynema; L 1, pachynema-like 1; L 2, pachynema-like 2.(E-H) Nuclear-spread spermatocytes from WT and KO mice were immunostained for SYCP3 together with RAD51 (E) or DMC1 (G) and quantification of RAD51 (F) or DMC1 (H) focus numbers at early zygonema, late zygonema, and pachynema. Representative images of early zygonema are shown. n=3 mice.
Figure 5(A-D) Representative nuclear spreads of WT and KO spermatocytes at leptonema (A), zygonema (B), pachynema (C) and diplonema (D). Spermatocytes were immunostained for REC8 and SYCP3. REC8 foci distribute along SYCP3-labeled structures. Magnified views are indicated by dashed areas.(E) Inter-REC8 distances along axial elements. Five stretches or homologs were measured and the average distance was calculated for each nucleus. Each point represents one nucleus. The upper panel is the schematic representation for distance measurement. n=3 mice.(F) Western blot analyses for REC8 and SEPARASE in spermatocytes isolated by FACS after Hoechst staining. n=3 mice. (G) Normalized density of REC8 in (F). n=3 mice.
Figure 6(E) Western blot analyses for SECURIN and CYCLIN B1 in spermatocytes isolated by FACS after Hoechst staining. n=3 mice. (F) Normalized density of SECURIN and CYCLIN B1 in (E). n=3 mice.
Figure 7(F) Western blot analyses for REC8 and SEPARASE for cells in (E). n=3 biological replicates. (G) Normalized density of REC8 in (F). n=3 biological replicates.(H) Western blot analyses for SECURIN and CYCLIN B1 for cells in (E). n=3 biological replicates. (I) Normalized density of SECURIN and CYCLIN B1 in (H). n=3 biological replicates.
Figure 3Representative photomicrograph of Golgi staining in hippocampus of a Tardbpfx/fx mouse.Sholl analysis of apical and basal dendritic arbors of CA1 pyramidal neurons from Tardbpfx/fx and CamKIIaCRE;Tardbpfx/fx mice. Results are presented as average ± SEM (N=3 mice per condition, 20 neurons per mouse). *, p<0.05; **, p<0.01. Data information: Results are presented as average ± standard error of the mean (SEM). All statistical tests were performed using 2-way ANOVA with Sidak post hoc analysis.High-magnification representative photomicrograph of Golgi staining of the dendritic arbour of a CA1 pyramidal neuron in a Tardbpfx/fx mouse. Black arrows denote selected dendritic spines.Spine density in apical and basal dendrites of CA1 pyramidal neurons of Tardbpfx/fx and CamKIIaCRE;Tardbpfx/fx mice. Results are presented as average ± SD (N=3 mice per condition, 15 sections per mouse; *, p<0.05; **, p<0.01). Data information: Results are presented as average ± standard error of the mean (SEM). All statistical tests were performed using 2-way ANOVA with Sidak post hoc analysis.Representative photomicrographs of a CamKIIaCRE;Tardbpfx/fx hippocampus after stereotaxic injection of EGFP-expressing lentivirus immunostained for EGFP (green) and NeuN (red), and counterstained with DAPI (blue). The injected area within CA1 is indicated in the merged panel.Expression of Tardbp (left), total Sort1 (center) and exon 17b Sort1 (right) mRNAs quantified by Q-PCR in micro-dissected CA1 of Tardbpfx/fx and CamKIIaCRE;Tardbpfx/fx mice after injection of EGFP-expressing lentivirus or Sortilin rescue virus. Results are presented as average ± SEM relative to levels in Tardbpfx/fx mice injected with EGFP virus, after normalization to Gapdh mRNA. (N=3 mice per condition). **, p<0.01. Data information: Results are presented as average ± standard error of the mean (SEM). All statistical tests were performed using 2-way ANOVA with Sidak post hoc analysis.Spine density in apical dendrites of CA1 pyramidal neurons of Tardbpfx/fx and CamKIIaCRE;Tardbpfx/fx mice after injection of EGFP-expressing lentivirus or Sortilin rescue virus. Results are presented as average ± SEM (N=3 mice per condition, 15 sections per mouse). **, p<0.01. Data information: Results are presented as average ± standard error of the mean (SEM). All statistical tests were performed using 2-way ANOVA with Sidak post hoc analysis.
Figure 4Percentage of change in field excitatory postsynaptic potential (fEPSP) recorded from hippocampal area CA1 after theta-burst stimulation (TBS) in Schaffer collaterals of hippocampal slices from Tardbpfx/fx and CamKIIaCRE;Tardbpfx/fx mice. Results are presented as average normalised to t=0 ± SEM (N=7 slices from 3 mice per condition). *, p<0.05; **, p<0.01; ***, p<0.001; ****, p<0.0001. Data information: Results are presented as average ± standard error of the mean (SEM). All statistical tests were performed using 2-way ANOVA with Sidak post hoc analysis.Percentage fEPSP change in CA1 after TBS in Schaffer collaterals of hippocampal slices from Tardbpfx/fx and CamKIIaCRE;Tardbpfx/fx mice stereotactically injected with EGFP-expressing lentivirus or Sortilin rescue virus (red) superimposed to the same data shown in panel (a) (black). Results are presented as average normalised to t=0 ± SEM (N=7 slices from 3 mice per condition). *, p<0.05; **, p<0.01; ***, p<0.001; ****, p<0.0001. Data information: Results are presented as average ± standard error of the mean (SEM). All statistical tests were performed using 2-way ANOVA with Sidak post hoc analysis.Percentage fEPSP change in CA1 after TBS in Schaffer collaterals of hippocampal slices from Tardbpfx/fx and CamKIIaCRE;Tardbpfx/fx mice under control conditions (black) or with BDNF (200ng/ml) perfused from t=0 (green). Results are presented as average normalised to t=0 ± SEM (N=7 slices from 3 mice per condition). *, p<0.05; **, p<0.01; ***, p<0.001; ****, p<0.0001. Data information: Results are presented as average ± standard error of the mean (SEM). All statistical tests were performed using 2-way ANOVA with Sidak post hoc analysis.Percentage of total time spent in the target quadrant or in the remaining three quadrants of the Barnes maze for Tardbpfx/fx and CamKIIaCRE;Tardbpfx/fx mice at 3 different probe times: 20-30 min after first training session (short-term memory) and 24h or 14 days after last training session (long-term or remote memory, respectively). Results are presented as average ± SEM (N=8 mice per condition; * p < 0.05, ** p < 0.01, *** p < 0.001). Data information: Results are presented as average ± standard error of the mean (SEM). All statistical tests were performed using 2-way ANOVA with Sidak post hoc analysis.
Figure 5Representative photomicrographs of cultured hippocampal neurons immunostained for TDP-43 (green), FLAG (red) and counterstained with DAPI (blue) in control conditions (untransduced) or infected with lentivirus expressing FLAG-tagged human TDP-43 12xQN construct.TDP-43 intensity in cell nuclei of untransduced or TDP-43 12xQN-infected hippocampal neurons normalized to mean nuclear intensity in untransduced neurons. Results are presented as average ± SEM (N=3 independent experiments; n=3 wells per condition in each experiment). Student's t-test; **, p<0.01. Data information: Results are presented as average ± standard error of the mean (SEM). All statistical tests were performed using Student's t-test (B)Expression of Tardbp (left), total Sort1 (center) and exon 17b Sort1 (right) mRNAs quantified by Q-PCR in hippocampal neurons untransduced (control) or infected with lentiviruses expressing Tardbp shRNA or human TDP-43 12xQN constructs. Values were first normalized to Gapdh mRNA levels, then plotted as average ± SEM relative to levels in untransduced neurons (N=3 independent experiments; n=3 wells per condition in each experiment). 1-way ANOVA with Tukey's post-hoc; **, p<0.01. Data information: Results are presented as average ± standard error of the mean (SEM). All statistical tests were performed using 2-way ANOVA with Sidak post hoc analysisBDNF secretion induced by KCl treatment as assessed by in-situ BDNF ELISA in cultured hippocampal neurons untransduced (control) or infected with lentiviruses expressing Tardbp shRNA or human TDP-43 12xQN constructs. Histogram bars show average ± SEM BDNF levels normalized to a standard curve (N=5 independent experiments; n=5 wells per condition in each experiment). **, p<0.01; ***, p<0.001. Data information: Results are presented as average ± standard error of the mean (SEM). All statistical tests were performed using 2-way ANOVA with Sidak post hoc analysisBDNF secretion in cultured hippocampal neurons untransduced (control) or infected with lentiviruses expressing Tardbp shRNA or human TDP-43 12xQN constructs together with either EGFP or Sortilin rescue viruses. Histogram bars show average ± SEM BDNF levels normalized to a standard curve (N=5 independent experiments; n=5 wells per condition in each experiment). **, p<0.01. Data information: Results are presented as average ± standard error of the mean (SEM). All statistical tests were performed using 2-way ANOVA with Sidak post hoc analysis
Figure 1A. Ig sequence diversification in wild type and h3.3. Each line represents an IGVLR gene from a population cells that have expanded for 36 divisions after cloning. Blue bars = gene conversions; green lollipops = point mutations; green bars = ambiguous mutations (Sale et al, 2001).B. Quantification of sequence diversification in wild type and two h3.3 clones expressed as unique events (gene conversions or point mutations) per kb per generation. (Sequences analysed: WT n = 142, for h3.3 c20 n = 140, for h3.3 c32 n = 190).C. Quantification of endogenous AID mRNA in wild type and h3.3 cells. The graph represents the mean and SD of four independent RNA extractions of wild type and h3.3c20. p value calculated with the unpaired T test.D. Fluctuation analysis for the formation of sIg-loss variants in wild type (black circles) and h3.3 clones (black diamonds) and in two wild type clones (blue circles), two h3.3 clones (blue diamonds) expressing hAIDup (Wang et al, 2009) at 15 - 20 times the level of wild type AID. The final column shows h3.3 cells with hAIDup complemented with H3.3 (blue triangles). Clones were expanded for 36 cell divisions at which point the percentage of sIgM negative cells in each population was determined by flow cytometry. Error bars represent mean and 1 S.D. P values calculated with the Mann-Whitney test.E. Ig sequence diversification in wild type, h3.3 and complemented h3.3 cells overexpressing hAIDup. Key as in (A) plus * = deletion or duplication.F. Mutation rate as a function of hAIDup expression in wild type and h3.3. Filled symbols represent clones overexpressing hAIDup, open symbols clones with natural AID expression. Linear regression lines are shown.
Figure 2B. Diversification in wild type and h3.3 cells expressing similar levels of hAIDup and UGI. Red lollipops = transitions at C/T; Black lollipops = other point mutations; blue bars = gene conversions.C. Mutation rate as a function of hAIDup expression in UGI-expressing wild type and h3.3 cells. Each clone was expanded for 36 cell divisions and hAIDup expression determined by qPCR during the last week of culture.
Figure 3A. Enrichment of H3.3 in the rearranged allele of the Ig light chain (IGVLR) compared with the unrearranged allele (IGVLUR). Each bar represents the mean of 3 independent ChIPs each assayed with 3 repeat qPCRs (**** = p<0.0001, unpaired T-test).B. Igλ mRNA levels in wild type and h3.3 cells determined by qPCR, normalised to EF-1α expression and to WT. n = 3 (ns = not significant, unpaired T-test).C. Surface Ig (sIg) in multiple clones of wild type (blue) and h3.3 (red) cells. Green = unstained control.D. ChIP for H3K4me3 and H3K36me3 in IGVLR and IGVLUR. Each bar represents the mean of 3 ChIPs for H3K4me3 and IgG and 2 for H3K36me3, each assayed with 3 qPCR repeats (statistical analysis as in Panel A).E. 4sUDRB mapping of transcription kinetics through IGVL. Representative locations of qPCR amplicons (blue) are shown relative to the TSS of IGVL (distance is shown in parenthesis). qPCR signals were normalised to the enrichment at time zero (before release). Error bars represent 1SD of qPCR triplicates.