The adenovirus-2 E1B-55K protein interacts with a mSin3A/histone deacetylase 1 complex

The adenovirus E1B-55K protein is a multifunctional phosphoprotein that regulates nuclear to cytoplasmic export of host cell and viral mRNAs during lytic viral growth. E1B-55K also blocks apoptosis by binding and functionally inactivating the human tumor suppressor protein p53. Here, rye show that E1B-55K interacts with histone deacetylase 1 (HDAC1) and the transcriptional corepressor protein;mSin3A, both in the adenovirus-transformed 293 cell line and during a lytic adenovirus infection, Furthermore, we show that the central amino acids 156-261 in E1B-55K are necessary for efficient HDAC1 interaction. Importantly, the E1B-55K/mSin3A/DAC1 complex is also enzymatically active, catalyzing deacetylation of a histone substrate peptide, Collectively, our results suggest that E1B-55K interaction with mSin3A/HDAC1 containing complexes may be significant for one or several of the multiple activities ascribed to this protein. (C) 2000 Federation of European Biochemical Societies, Published by Elsevier Science B.V. All rights reserved.