Fig. 5.
Increased readthrough of TGA-G1,2 with nonaminoglycosides. XP-C cells with TGA-G1,2 were incubated with nonaminoglycosides and aminoglycosides for 3 d. (A) MTT survival assay. The effective doses of PTC124, BZ16, and RTC14 used were less toxic in TGA-A1,2 compared with Geneticin and gentamicin. (B) Measurement of XPC mRNA. Treatment with PTC124, BZ16, and RTC14 and Geneticin resulted in significantly increased XPC mRNA. **P < 0.005. (C) Immunofluorescence assay in normal and XP-C TGA-G1,2 cells 1 h after local UV irradiation. Geneticin, gentamicin, PTC124, BZ16, and RTC14 induce post-UV XPC protein localization. (D) Quantification of XPC protein at sites of UV damage 1 h post UV (from C). Bars indicate mean ± SD of the percent positive cells for XPC. One hundred nuclei were scored for each bar. *P < 0.05, **P < 0.005, ***P < 0.0005. (E and F) Immunofluorescence assay for detection of 6–4PPs (E) and CPDs (F) 6 and 24 or 48 h after local UV irradiation. Bars indicate mean ± SD of the percent positive cells for 6-4PP and CPDs; 100 nuclei were scored.