A human cytomegalovirus early promoter with upstream negative and positive cis-acting elements: IE2 negates the effect of the negative element, and NF-Y binds to the positive element.

摘要: The human cytomegalovirus early promoter for the UL4 gene, which codes an viral envelope glycoprotein designated gpUL4, requires immediate-early protein two (IE2) synthesis to be activated (C.-P. Chang, C. L. Malone, and M. F. Stinski, J. Virol. 63:281, 1989). We investigated cis-acting trans-acting factors that regulate transcription from this promoter. In transient transfection assays, IE2 negated effect of upstream negative element enhanced downstream gene expression. A positive contributed activity when was deleted or present. cellular protein(s) binds further investigation. characterized. Two DNA sequence-specific complexes were detected with probes spanning region containing cytomegalovirus-infected fibroblast cell nuclear extracts. more slowly migrating complex labeled A, faster B. Only B mock-infected Competition experiments confirmed specificity complexes. bound in both contacts a CCAAT box imperfect dyad symmetry (5'CCAATCACTGG3'). Either within could compete binding factor. Mutation resulted decrease transcriptional factor, antigenically related factor-Y (NF-Y), found Events associated infection caused phosphorylation A. Dephosphorylation DNA-binding converts NF-Y is not known.