The nuclear receptor coactivator 1 (NCOA1), also called steroid receptor coactivator-1 (SRC-1), is a transcriptional coregulatory protein that contains several nuclear receptorâÂÂinteracting domains and possesses intrinsic histone acetyltransferase activity. It is encoded by the gene NCOA1.
NCOA1 is recruited to DNA promoter sites by ligand-activated nuclear receptors. NCOA1, in turn, acylates histones, which makes downstream DNA more accessible to transcription. Hence, NCOA1 assists nuclear receptors in the upregulation of DNA expression as a coactivator.
Nuclear receptor coactivator 1 possesses a basic helix-loop-helix (bHLH) domain and has been shown to interact with: