Fig. 1

Loss of ATXN1L results in CIC instability. a Representative Western blot of ATXN1L^WT (HEK) and ATXN1L^KO cell lines (A10, A30, B21) treated with MG132. DMSO was used as a negative control. Below: barplots showing quantification of CIC protein expression. b Representative Western blot of ATXN1L^WT (HEK) and ATXN1L^KO cell lines (A10, A30, B21), ectopically overexpressing FLAG-tagged ATXN1L. Below: barplots showing quantification of CIC protein expression. c Representative Western blot of siRNA knockdown of ATXN1 and ATXN1L in NHA. Scrambled siRNA was used as a negative control. Below: barplots showing quantification of CIC protein expression. d Representative Western blot of ATXN1L^WT (HEK) and ATXN1L^KO cell lines (A30) ectopically overexpressing FLAG-tagged wild-type ATXN1L or mutant ATXN1L-V485A. e Barplots showing quantification of ubiquitin Western blots normalized to total CIC Western blots. f Representative Western blot of CIC immunoprecipitation in ATXN1L^WT (NHA) and ATXN1L^KO (B82) cell lines treated with MG132. DMSO was used as a negative control. g Immunofluorescence images of proximity ligation assay showing CIC-ubiquitin interaction in ATXN1L^WT (NHA) cell lines following siRNA knockdown of ATXN1L. Scrambled siRNA was used as a negative control. White bars denote 10 μm. h Tukey boxplots showing quantification of the number of CIC-ubiquitin foci/cell. Western blot quantifications were collected from 3 independent experiments and were normalized to vinculin unless specified otherwise. Error bars represent one standard deviation. PLA quantifications were collected from 65 individual cells. p values were calculated using the two-tailed independent Student’s t test. Statistically significant values are denoted (*p < 0.05, **p < 0.01, ***p < 0.001). Individual data values can be found in Additional file 17: Table S10