Fig. 5.

Clonogenic survival assay for primary skin fibroblasts from p53-KO and TRI-KO mice. (Upper) Into 6-well plates, 10⁵, 5 × 10⁴, and 2 × 10⁴ cells were seeded in duplicates, irradiated with UV, and then incubated for 9–10 days until colonies were readily visible. Colonies were then stained with 5% methylene blue. (Lower) UV survival curves obtained from 3 experiments including the 1 shown in Upper. Error bars indicate standard errors of the mean and the asterisks indicate statistically significant (P < 0.01) difference in clonogenic survival.