Stimulated By Retinoic Acid Gene 13 (STRA13)

Stra13 is a transcriptional repressor related within its basic helix–loop–helix domain with the Drosophila Hairy. Stra13 expression is transcriptionally repressed and maintained at a low level in cells through a negative autoregulatory mechanism that is brought about by its interaction with the corepressor histone deacetylase (HDAC1). This interaction requires the Stra13 C-terminal domain containing three α-helices, which are also functionally critical to its repressive activity. Thus, inhibition of HDAC activity by TSA abrogates Stra13-mediated repression of its promoter, resulting in induction of Stra13 expression that is coincident with TSA-induced growth arrest. Further, once induced, Stra13 strongly represses the expression of the cell proliferation-associated gene c-Myc through an HDAC1-independent pathway that involves its interaction with the basal transcription factor TFIIB.