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B-Myb switches from Cyclin/Cdk-dependent to Jnk- and p38 kinase-dependent phosphorylation and associates with SC35 bodies after UV stress.

ABSTRACT: B-Myb is a highly conserved member of the Myb transcription factor family that has essential roles in cell-cycle progression. Recent work has suggested that B-Myb is also involved in the cellular DNA-damage response. Here, we have investigated the fate of B-Myb in UV-irradiated cells. UV stress leads to the appearance of phosphorylated B-Myb in nuclear SC35 speckles during transcriptional shutdown. Furthermore, we show that UV irradiation leads to a change of the phosphorylation pattern of B-Myb, which is caused by a switch from Cyclin/Cdk-dependent to Jnk and p38 kinase-dependent phosphorylation. Taken together, we have identified Jnk and p38 kinase as novel regulators of B-Myb and established the localization of phosphorylated B-Myb in SC35 speckles as a potential novel regulatory mechanism for B-Myb in UV irradiated cells.

SUBMITTER: Werwein E

PROVIDER: S-EPMC3734824 | biostudies-literature | 2013 Feb

REPOSITORIES: biostudies-literature

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B-Myb switches from Cyclin/Cdk-dependent to Jnk- and p38 kinase-dependent phosphorylation and associates with SC35 bodies after UV stress.

Werwein E E Dzuganova M M Usadel C C Klempnauer K-H KH

Cell death & disease 20130228

B-Myb is a highly conserved member of the Myb transcription factor family that has essential roles in cell-cycle progression. Recent work has suggested that B-Myb is also involved in the cellular DNA-damage response. Here, we have investigated the fate of B-Myb in UV-irradiated cells. UV stress leads to the appearance of phosphorylated B-Myb in nuclear SC35 speckles during transcriptional shutdown. Furthermore, we show that UV irradiation leads to a change of the phosphorylation pattern of B-Myb ...[more]

PMID: 23449447

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