Fig. 4
Deubiquitinating activity of Usp12 is not required for suppression of mHTT toxicity. a Schematic representation of Usp12 domain structure. The conserved active-site cysteine (C48) is highlighted in red. b, c Cumulative risk of death plots for primary neurons co-transfected with mHTT-N568Q138 and Usp12, Usp12 mutants that lack deubiquitinating activity in vitro (Usp12-C48S), or retain activity (Usp12-C50S), Usp12 containing both mutations (Usp12-DBLCS), or empty vector control; statistical data are summarized in Table 2. d Expression of Usp12 and Usp12 mutants in HEK cells transfected with these plasmids. Usp12-C48S samples are from a separate gel. Tubulin was assayed as a loading control, s.e. are shown. One-way ANOVA with multiple comparisons, ****p < 0.0001, ***p < 0.001, *p < 0.05. e Relative Wdr20 and Wdr48 mRNA levels of a rat C6 cell line transfected with Wdr20 and Wdr48 siRNAs, respectively. *p < 0.01, s.e.m. are shown. f, g Cumulative risk of death plots for primary neurons co-transfected with mHTT-N568Q138, Usp12-C48S, and siRNAs against either Wdr20 or Wdr48 (f) or both (g). HR was used to estimate the relative risk of death and results are summarized in Supplementary Table 6. h Survival analysis of human neurons differentiated from patient-derived iPSCs (unaffected individual, control; HD patient, HDQ53). Cox proportional hazards analysis was used to estimate the relative risk of death, or hazard ratio (HR), and the p value was determined with the log rank test (*p < 0.05, **p < 0.01, ***p < 0.001) (Table 3)
