Deoxynucleotidyltransferase Terminal Interacting Protein 2 (DNTTIP2)

ERBP C-terminal and N-terminal fragments interacted with the DNA binding domain and hinge region of ER-alpha. Binding of the C-terminal ERBP fragment was enhanced in the presence of estrogen. ERBP also bound ER-beta (ESR2), but this interaction was not affected by estrogen. Overexpression of ERBP enhanced ER-alpha-mediated transactivation in an estrogen-dependent manner. Transcriptional activity assay showed that ERBP itself lacked intrinsic transcription activity.

The deduced 756-amino acid protein has a calculated molecular mass of approximately 82 kD. ERBP localized to the nucleus in HeLa cells and in transfected COS-7 cells. Northern blot analysis detected expression of a 2.4-kb transcript in all tissues examined, with high levels in testis.