“…Conserved region 3 is unique to the larger 13S form of E1A and encodes a domain that exhibits strong transactivation potential (Green et al, 1988) and interacts with the mammalian Srb/Mediator complex (Boyer et al, 1999). The transforming activity of E1A, residing mainly in the conserved regions 1 and 2 (Whyte et al, 1998b), is brought about by interaction with a large number of cellular proteins, many of which are cell cycle regulatory proteins involved in transcription and/or chromatin modi®cation such as Rb (Whyte et al, 1998a), p107 and p130 (Whyte et al, 1989;Hannon et al, 1993), cyclins A and E (Pines and Hunter, 1990;Giordano et al, 1991), the cdk inhibitor p27 kip1 (Mal et al, 1996) and the transcriptional adaptors p300 and CBP (Arany et al, 1994;Eckner et al, 1994).…”