title: Differentiation-dependent changes in levels of C/EBPβ repressors and activators regulate human papillomavirus type 31 late gene expression.
abstract: The liver-enriched transcriptional activator protein (LAP) isoform of CCAAT/enhancer binding protein β (C/EBPβ) is shown to be a major activator of differentiation-dependent human papillomavirus (HPV) late gene expression, while the liver-enriched inhibitory protein (LIP) isoform negatively regulates late expression. In undifferentiated cells, LIPs act as dominant-negative repressors of late expression, and upon differentiation, LIP levels are significantly reduced, allowing LAP-mediated activation of the late promoter. Importantly, knockdown of C/EBPβ isoforms blocks activation of late gene expression from complete viral genomes upon differentiation.
authors.affiliation: Department of Microbiology-Immunology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois, USA.
authors.forename: Vignesh
authors.initials: V
authors.lastname: Gunasekharan
authors.forename: Guylaine
authors.initials: G
authors.lastname: Haché
authors.forename: Laimonis
authors.initials: L
authors.lastname: Laimins
mesh_terms: D001483:Base Sequence; D001665:Binding Sites; D022782:CCAAT-Enhancer-Binding Protein-beta / Q000378:metabolism*; D002454:Cell Differentiation / Q000235:genetics*; D002460:Cell Line; D015967:Gene Expression Regulation, Viral; D020868:Gene Silencing; D058952:Human papillomavirus 31 / Q000235:genetics* / Q000378:metabolism*; D006801:Humans; D015603:Keratinocytes / Q000166:cytology / Q000378:metabolism; D016297:Mutagenesis, Site-Directed; D011401:Promoter Regions, Genetic; D020033:Protein Isoforms / Q000378:metabolism; D020218:Response Elements; D014158:Transcription, Genetic
chemical_list: D022782:CCAAT-Enhancer-Binding Protein-beta; D020033:Protein Isoforms