THE TRANSCRIPTIONAL COACTIVATOR PROTEINS P300 AND CBP STIMULATE ADENOVIRUS E1A CONSERVED REGION-1 TRANSACTIVATION INDEPENDENT OF A DIRECT INTERACTION

p300 and CBP are two related transcriptional coactivator proteins requ ired by many cellular transcription factors for activity. The adenovir us E1A protein binds p300 and CBP through its amino-terminus and conse rved region (CR) 1, Fusing CR1 to a heterologous DNA-binding domain cr eates a potent transcriptional activator, suggesting that CR1 might ac tivate transcription by recruiting p300/CBP to the promoter, We show t hat both p300 and CBP enhances CR1-dependent transactivation, However, this enhancement occurs independently of a direct interaction with E1 A and does not correlate with the CR1 activator function. (C) 1997 Fed eration of European Biochemical Societies.