Figure 5. ATXN1 requires CIC binding to maintain oligomer conformation.
(A) Western blot of Hela cells co-transfected with ATXN1(82Q) and increasing concentrations (from 0.5 to 3 μg) of wild type CIC (left panel) or increasing concentrations of mutant CIC/W37A (right panel). Membranes were probed with F11G3 to determine the levels of oligomers. * indicated change in exposure of the membrane. (B) Quantification of oligomers from Western blot analysis (A), demonstrated that increased oligomer levels correlated with increases of transfected wild-type CIC. Mutant CIC/W37A produced no effect on the amount of oligomers detected by Western blot. n = 4. *p < 0.05, **p < 0.01 and ***p < 0.001. (C) Western blot of Hela cells co-transfected with ATXN1(30Q) and increasing concentrations (from 0.5 to 3 μg) of wild-type CIC (left panel) or increasing concentrations of mutant CIC/W37A (right panel). Membranes were probed with F11G3 to determine the levels of oligomers. Almost no oligomers were detected in any of the measured conditions. * indicated change in exposure of the membrane. (D) ELISA using F11G3 shows that cells transfected with ATXN1(82Q) have high levels of oligomers, but cells transfected with ATXN1(30Q) had almost no detectable oligomers. Increasing amounts of oligomers were observed when cells transfected with ATXN1(82Q) were co-transfected with increasing amounts of wild type CIC but not mutant CIC/W37A. n = 4. *p < 0.05, **p < 0.01 and ***p < 0.001.
Figure 5—figure supplement 1. CIC facilitates ATXN1 oligomerization.
