SIN3 Homolog A (SIN3A)

SIN3A is a transcriptional regulatory protein. It contains paired amphipathic helix (PAH) domains, which are important for protein-protein interactions and may mediate repression by the Mad-Max complex.The deduced 1,219-amino acid protein contains 4 paired amphipathic helix (PAH) domains.

Sin3a shares significant homology with yeast Sin3 and mouse Sin3b. The highest homology lies within the 4 PAH domains and between PAH3 and PAH4. Sin3a and Sin3b share less homology at their N termini.A multiprotein complex including HDAC1, HDAC2, and SIN3A was recruited to SP1 and SP3 sites of the LHR promoter and silenced SP1/SP3-driven LHR gene transcription. SIN3A interacted directly with both HDACs in the complex.