Dax1 binds to Oct3/4 and inhibits its transcriptional activity in embryonic stem cells.

ABSTRACT: Embryonic stem (ES) cells are pluripotent cells derived from the inner cell mass of blastocysts. Transcription factor Oct3/4 is an indispensable factor in the self-renewal of ES cells. In this study, we searched for a protein that would interact with Oct3/4 in ES cells and identified an orphan nuclear hormone receptor, Dax1. The association of Dax1 with Oct3/4 was mediated through the POU-specific domain of Oct3/4. Ectopic expression of Dax1 inhibited Oct3/4-mediated activation of an artificial Oct3/4-responsive promoter. Expression of Dax1 in ES cells also reduced the activities of Nanog and Rex1 promoters, while knockdown of Dax1 increased these activities. Pulldown and gel shift assays revealed that the interaction of Dax1 with Oct3/4 abolished the DNA binding activity of Oct3/4. Chroma

SUBMITTER: Sun C 

PROVIDER: S-EPMC2725734 | biostudies-literature | 2009 Aug

REPOSITORIES: biostudies-literature