| In this study , we demonstrate that CBP is markedly induced upon differentiation of the Caco 2 intestinal cell line and augments Cdx 2 dependent transcriptional activity . ^^^ Cdx 2 interacts with the amino terminal domain of CBP , and the two proteins coexist in vivo within the same nuclear protein complex . ^^^ Moreover , expression of the CBP domain that interacts with Cdx 2 acts as a dominant negative inhibitor of transcriptional activation by Cdx 2 . ^^^ |