P53 promotes repair of heterochromatin DNA by regulating JMJD2b and SUV39H1 expression.

ABSTRACT: Constitutive heterochromatin (HC) is important for maintaining chromosome stability, but also delays the repair of DNA double-strand breaks (DSBs). DSB repair in complex mammalian genomes involves a fast phase (2-6 h) in which most of the breaks are rapidly repaired, and a slow phase (up to 24 h) in which the remaining damages in HC are repaired. We found that p53 deficiency delays the slow-phase DNA repair after ionizing irradiation. p53 deficiency prevents downregulation of histone H3K9 trimethylation at the pericentric HC after DNA damage. Moreover, p53 directly induces expression of the H3K9 demethylase Jumonji domain 2 family demethylase (JMJD2b) through promoter binding. The p53 activation also indirectly downregulates expression of the H3K9 methyltransferase SUV39H1. Depletion of JM

SUBMITTER: Zheng H 

PROVIDER: S-EPMC3912226 | biostudies-literature | 2014 Feb

REPOSITORIES: biostudies-literature