Impaired regulation of tumor suppressor p53 caused by mutations in the xeroderma pigmentosum DDB2 gene: mutual regulatory interactions between p48(DDB2) and p53.

ABSTRACT: Tumor suppressor p53 controls cell cycle progression and apoptosis following DNA damage, thus minimizing carcinogenesis. Mutations in the human DDB2 gene generate the E subgroup of xeroderma pigmentosum (XP-E). We report here that XP-E strains are defective in UV irradiation-induced apoptosis due to severely reduced basal and UV-induced p53 levels. These defects are restored by infection with a p53 cDNA expression construct or with a DDB2 expression construct if and only if it contains intron 4, which includes a nonmutated p53 consensus-binding site. We propose that both before and after UV irradiation, DDB2 directly regulates p53 levels, while DDB2 expression is itself regulated by p53.

SUBMITTER: Itoh T 

PROVIDER: S-EPMC207631 | biostudies-literature | 2003 Nov

REPOSITORIES: biostudies-literature