title: A suppressive effect of Sp1 recruitment to the first leader 5' splice site region on L4-22K-mediated activation of the adenovirus major late promoter.
abstract: Transcription from the adenovirus major late promoter (MLP) requires binding of late phase-specific factors to the so-called DE element located approximately 100 base pairs downstream of the MLP transcriptional start site. The adenovirus L4-22K protein binds to the DE element and stimulates transcription from the MLP via a DE sequence-dependent mechanism. Here we use a transient expression approach to show that L4-22K binds to an additional site downstream of the MLP start site, the so-called R1 region, which includes the major late first leader 5' splice site. Binding of L4-22K to R1 has a suppressive effect on MLP transcription. L4-22K binds to the distal part of R1 and stimulates the recruitment of Sp1 and other cellular factors to a site overlapping the first leader 5' splice site. Binding of Sp1 to the 5' splice site region had an inhibitory effect on L4-22K-activated MLP transcription.
authors.affiliation: Department of Medical Biochemistry and Microbiology, Uppsala Biomedical Center, Uppsala University, S-751 23 Uppsala, Sweden. Electronic address: xin.lan@imbim.uu.se.
authors.forename: Susan
authors.initials: S
authors.lastname: Lan
authors.affiliation: Department of Medical Biochemistry and Microbiology, Uppsala Biomedical Center, Uppsala University, S-751 23 Uppsala, Sweden. Electronic address: sara.ostberg@imbim.uu.se.
authors.forename: Sara
authors.initials: S
authors.lastname: Östberg
authors.affiliation: Department of Medical Biochemistry and Microbiology, Uppsala Biomedical Center, Uppsala University, S-751 23 Uppsala, Sweden. Electronic address: tanel.punga@imbim.uu.se.
authors.forename: Tanel
authors.initials: T
authors.lastname: Punga
authors.affiliation: Department of Medical Biochemistry and Microbiology, Uppsala Biomedical Center, Uppsala University, S-751 23 Uppsala, Sweden. Electronic address: goran.akusjarvi@imbim.uu.se.
authors.forename: Göran
authors.initials: G
authors.lastname: Akusjärvi
mesh_terms: D000256:Adenoviridae / Q000235:genetics / Q000502:physiology*; D002460:Cell Line; D015967:Gene Expression Regulation, Viral; D054884:Host-Pathogen Interactions; D006801:Humans; D011401:Promoter Regions, Genetic; D011485:Protein Binding; D022821:RNA Splice Sites; D016329:Sp1 Transcription Factor / Q000378:metabolism*; D017361:Viral Nonstructural Proteins / Q000378:metabolism*
chemical_list: C571219:L4-22K protein, adenovirus; D022821:RNA Splice Sites; D016329:Sp1 Transcription Factor; C108209:SP1 protein, human; D017361:Viral Nonstructural Proteins
keywords: Adenovirus; L4-22K; Major late promoter; Sp1; Transcription