function:Transcription activator that binds DNA cooperatively with DP proteins through the E2 recognition site, 5'-TTTC[CG]CGC-3' found in the promoter region of a number of genes whose products are involved in cell cycle regulation or in DNA replication. The DRTF1/E2F complex functions in the control of cell-cycle progression from g1 to s phase. E2F-2 binds specifically to RB1 protein, in a cell-cycle dependent manner.,PTM:Phosphorylated by CDK2 and cyclin A-CDK2 in the S-phase.,similarity:Belongs to the E2F/DP family.,subunit:Component of the DRTF1/E2F transcription factor complex. Forms heterodimers with DP family members. The E2F-2 complex binds specifically hypophosphorylated retinoblastoma protein RB1. During the cell cycle, RB1 becomes phosphorylated in mid-to-late G1 phase, detaches from the DRTF1/E2F complex, rendering E2F transcriptionally active. Viral oncoproteins, notably E1A, T-antigen and HPV E7, are capable of sequestering RB protein, thus releasing the active complex. Binds EAPP.,tissue specificity:Highest level of expression is found in placenta, low levels are found in lung. Found as well in many immortalized cell lines derived from tumor samples.,