FIGURE 8.

Inactivation of UBQLN2 in cells induces serpin aggregation. (A) Immunoblots comparing Serpin A1 and B1 levels in parental HeLa and NSC34 lines to two independent UBQLN2 knockout lines (KO8/KO12 and KO20/KO69, respectively) for each line. (B) Both HeLa and NSC34 UBQLN2 knockout cell lines show increased accumulation of high molecular weight (High MWt) serpin bands, suggesting protein aggregation. *p < 0.05, **p < 0.01. (C) Filter trap assays using cell lysate and media aliquots from the parental HeLa and UBQLN2 KO8 cells as well as the parental NSC34 and UBQLN2 KO20 cells. UBQLN2 knockout in either cell type results in increased serpin aggregation in cell lysates and the media. (D and E) Quantification of the signals for the filter trap assays shown in B. *p < 0.05, **p < 0.01, ***p < 0.001, ****p < 0.0001. n = 3–6 replicates/cell line and results were reproduced in at least two independent experiments