Atypical E2F transcription factor that participates in various processes such as angiogenesis and polyploidization of specialized cells. Mainly acts as a transcription repressor that binds DNA independently of DP proteins and specifically recognizes the E2 recognition site 5'-TTTC[CG]CGC-3'. Directly represses transcription of classical E2F transcription factors such as e2f1. Acts as a regulator of S-phase by recognizing and binding the E2-related site 5'-TTCCCGCC-3' and mediating repression of G1/S-regulated genes (By similarity). Acts as a promoter of sprouting angiogenesis, possibly by acting as a transcription activator and promoting expression of vegfa. Homodimer and heterodimer: mainly forms homodimers and, to a lesser extent, heterodimers with e2f7. In contrast to classical members of the E2F transcription factor, atypical members contain 2 DNA-binding domains and regulate transcription in a DP-independent manner. Both DNA-binding domains are required for DNA-binding and are proposed to form an intramolecular structure that is similar to the winged helix structure of the E2F-DP heterodimer (By similarity). Embryos lacking both e2f7 and e2f8 contain multiple intersegmental arteries that completely fail to migrate from the dorsal aorta. Gross morphology of these embryos and initial formation of main axial vessels are unaltered. Belongs to the E2F/DP family.