Figure 6.

Effect of CC-885 and CC-90009 on TPP1 PTC readthrough. (A, B) GM16485 primary fibroblasts derived from a late infantile neuronal ceroid lipofuscinosis (CLN2) patient with TPP1 nonsense mutations (R127X/R208X) were exposed to the indicated concentrations of CC-885 (A) or CC-90009 (B) for 72 h and eRF3a, eRF3b and eRF1 levels were determined. (C–F) GM16485 fibroblasts were exposed to the indicated concentrations of CC-885 (C, E) or CC-90009 (D, F), alone (C, D) or in combination with 20 μg/ml G418 (E, F) for 72 h and TPP1 levels (proenzyme, P; mature, M) were measured. Total TPP1 levels (P + M) are expressed relative to the amount of total TPP1 in cells treated with 20 μg/ml G418. In panels A–F, GAPDH was used as loading control. In panel E, X indicates where lower amounts of protein were loaded because insufficient numbers of cells were recovered. (G, H) TPP1 activity from the same cell extracts as in C–F was determined in triplicate samples (±SD) and expressed as % activity relative to that of WT fibroblasts. * indicates statistically significant difference to untreated samples (P < 0.01).