Competitive inhibitor of E2F-mediated transactivation activity. Impairs E2F-mediated cell-cycle progression from G(1) to S phase. Heterodimer: with E2F family members. TFDP3/E2F heterodimers do not bind DNA and repress E2F-dependent transcriptional activity. Translocates to the nucleus on heterodimerization with E2F family members. Predominantly expressed in testis. Low level of expression in pancreas. Highly expressed in ovarian and colon cancer cell lines. In response to DNA damage. The potential DNA-binding domain differs in sequence from that of other DP family members and cannot bind DNA. Belongs to the E2F/DP family. Truncated N-terminus.