Cited-2 is a 270aa protein that functions by binding to the CH1 region of CREB binding protein (CBP)/p300. This binding interferes with certain transcription factors like HIF1a and STAT2 blocking their ability to bind and interact with CBP/p300. Cited-2 knockout mice die due to defects in heart and neural tube development. Mutations in Cited-2 have been reported in patients with congenital heart defects. It appears Cited-2 modulates apoptosis by a p53 independent pathway whereby the details still need to be elucidated.