Interplay with the Mre11-Rad50-Nbs1 complex and phosphorylation by GSK3? implicate human B-Myb in DNA-damage signaling.

ABSTRACT: B-Myb, a highly conserved member of the Myb transcription factor family, is expressed ubiquitously in proliferating cells and controls the cell cycle dependent transcription of G2/M-phase genes. Deregulation of B-Myb has been implicated in oncogenesis and loss of genomic stability. We have identified B-Myb as a novel interaction partner of the Mre11-Rad50-Nbs1 (MRN) complex, a key player in the repair of DNA double strand breaks. We show that B-Myb directly interacts with the Nbs1 subunit of the MRN complex and is recruited transiently to DNA-damage sites. In response to DNA-damage B-Myb is phosphorylated by protein kinase GSK3? and released from the MRN complex. A B-Myb mutant that cannot be phosphorylated by GSK3? disturbs the regulation of pro-mitotic B-Myb target genes and leads to inappropriate mitotic entry in response to DNA-damage. Overall, our work suggests a novel function of B-Myb in the cellular DNA-damage signalling.

SUBMITTER: Henrich SM 

PROVIDER: S-EPMC5269693 | biostudies-literature | 2017 Jan

REPOSITORIES: biostudies-literature