Involved in the regulation of the G1/S transition. Increases the DNA binding and the transactivation activities of E2F proteins after heterodimerization. The complex DPA/E2FA promotes cell division and acts as a regulator of the endocycle. Positively regulates the activity of S phase-specific genes. Heterodimer with E2F. Interacts preferentially with E2FA and E2FB, but also with E2FC. Interaction with E2F stimulates the nuclear translocation. Strongly expressed in the actively dividing tissues of the shoot apical meristem, young leaf primordia, the vascular tissues of the maturing leaf primordia and axillary buds. Expressed in a cell cycle-dependent manner. Low expression at the G1/S transition and increases during the S phase. S/G2 transitions. Up-regulated by the transcription factor ERF114. The DIM domain (143-214) is necessary but not sufficient for heterodimerization. Belongs to the E2F/DP family. Truncated N-terminus.