NCOA5 (Nuclear Receptor Coactivator 5), also known as CIA (Coactivator Independent of AF-2 function), has been shown interact exclusively with estrogen receptor alpha (ERalpha) and beta (ERbeta) to function as a coactivator and enhance transcriptional activation by ER. NCOA5 has also been demonstrated to function as a corepressor of MYC/c-myc in response to 17-beta estradiol.
