title: HBV X protein alters the DNA binding specificity of CREB and ATF-2 by protein-protein interactions.
abstract: The hepatitis B virus (HBV) X gene product trans-activates viral and cellular genes. The X protein (pX) does not bind independently to nucleic acids. The data presented here demonstrate that pX entered into a protein-protein complex with the cellular transcriptional factors CREB and ATF-2 and altered their DNA binding specificities. Although CREB and ATF-2 alone did not bind to the HBV enhancer element, a pX-CREB or pX-ATF-2 complex did bind to the HBV enhancer. Thus, the ability of pX to interact with cellular factors broadened the DNA binding specificity of these regulatory proteins and provides a mechanism for pX to participate in transcriptional regulation. This strategy of altered binding specificity may modify the repertoire of genes that can be regulated by transcriptional factors during viral infection.
authors.affiliation: Department of Microbiology and Immunology, University of Colorado School of Medicine, Denver 80262.
authors.forename: H F
authors.initials: HF
authors.lastname: Maguire
authors.forename: J P
authors.initials: JP
authors.lastname: Hoeffler
authors.forename: A
authors.initials: A
authors.lastname: Siddiqui
mesh_terms: D017362:Cyclic AMP Response Element-Binding Protein; D004247:DNA / Q000378:metabolism*; D004268:DNA-Binding Proteins / Q000494:pharmacology*; D004357:Drug Synergism; D004591:Electrophoresis, Polyacrylamide Gel; D015967:Gene Expression Regulation, Viral; D005814:Genes, Viral; D006801:Humans; D011485:Protein Binding; D015534:Trans-Activators / Q000502:physiology*; D014157:Transcription Factors / Q000494:pharmacology; D015533:Transcriptional Activation; D054334:Viral Regulatory and Accessory Proteins
chemical_list: D017362:Cyclic AMP Response Element-Binding Protein; D004268:DNA-Binding Proteins; D015534:Trans-Activators; D014157:Transcription Factors; D054334:Viral Regulatory and Accessory Proteins; C057628:hepatitis B virus X protein; D004247:DNA