Extended Data Fig. 5: PA28γ/PSME-3 regulates proteostasis of polyQ-expanded peptides in neurons and muscle.
a, Filter trap of neuronal polyQ67::YFP aggregation with anti-GFP in day 6 adults upon neuronal-specific psme-3 knockdown. Representative of three independent experiments. b-c, Western blot of polyQ67 protein levels upon psme-3 overexpression (OE) at 15 °C (b) or 25 °C (c). Graphs represent the relative percentage of polyQ67 protein levels upon PSME-3 overexpression (corrected for α-tubulin loading control) to control Q67 (mean ± s.e.m., n = 3 independent experiments). d, Filter trap of polyQ67 aggregation upon psme-3 overexpression at 15 °C and 25 °C. Representative of three independent experiments. e, Thrashing movements over a 30-s period (n = 100 worms from two independent experiments). The box plot represents the 25th–75th percentiles, the line depicts the median and the whiskers show the min–max values. f, Western blot of polyQ67 levels upon psme-3 overexpression at 20 °C. Graph represents the relative percentage of polyQ67 protein levels (corrected for α-tubulin) to control Q67 (mean ± s.e.m., n = 3 independent experiments). g, Filter trap of neuronal polyQ67 aggregation at 20 °C (representative of three independent experiments). h, Thrashing movements over a 30-s period (n = 50 worms per condition). The box plots and lines represent the 25th–75th percentiles and median, respectively. The whiskers show the min–max values. In b-h, we analyzed day 3-adult worms. i, Western blot of day 6 adult worms expressing polyQ40::YFP in muscle cells (detected by anti-GFP antibody). Graph represents the relative percentage of polyQ40 protein levels (corrected for α-tubulin) to 25 °C (mean ± s.e.m., n = 3 independent experiments). j, Western blot of polyQ40 protein levels in day 6 adult worms upon psme-3 RNAi at 15 °C. Graph represents the relative percentage of polyQ40 levels (corrected for α-tubulin) to 15 °C Vector RNAi (mean ± s.e.m., n = 3 independent experiments). RNAi was initiated at day 1 of adulthood. Statistical comparisons were made by two-tailed Student’s t-test for paired (b, c, f, i, j) or unpaired samples (e, h). P value: *P < 0.05, **P < 0.01, ****P < 0.0001, NS = not significant (P > 0.05). All the significant changes were also significant after correction for multiple testing by FDR (q value< 0.05). Source Data contains exact P and q values.
