Fig. 7.

Co-administration of C4 and C18 enhance the protein stability of CFTR mutants. HEK-293 cell lines stably expressing the G85E, E92K, L1077P, or M1101K constructs were treated with C4 and C18 (each 5 µM, 16 h). Subsequently, protein synthesis was blocked by applying cycloheximide (CHX, 25 µM/mL), and cells were harvested at different time points (0–8 h). Immunoblots and quantification of CFTR bearing (A) G85E, (B) E92K, (C) L1077P, and (D) M1101K (ANOVA, n = 4). Data are normalized to control (untreated sample) values; vs. 0 h without C4+C18: *P < 0.05, **P<0.01; vs. 0 h with C4+C18: ^#P < 0.05, ^##P < 0.01; ND: not detected. Bars represent densitometric quantification of immature band B (white) and mature band C (gray). Ezrin (Ez) was used as a loading control. C: control = untreated without CHX. The chase time are from 1–8hrs. Membranes were cut into two strips and incubated with primary antibodies against CFTR or ezrin.