title: Nature of a paramyxovirus replication promoter influences a nearby transcription signal.
abstract: The genomic and antigenomic 3' ends of the Sendai virus replication promoters are bi-partite in nature. They are symmetrically composed of leader or trailer sequences, a gene start (gs) or gene end (ge) site, respectively, and a simple hexameric repeat. Studies of how mRNA synthesis initiates from the first gene start site (gs1) have been hampered by the fact that gs1 is located between two essential elements of the replication promoter. Transcription initiation, then, is separated from the replication initiation site by only 56 nt on the genome, so that transcription and replication may sterically interfere with each other. In order to study the initiation of Sendai virus mRNAs without this possible interference, Sendai virus mini-genomes were prepared having tandem promoters in which replication takes place from the external one, whereas mRNA synthesis occurs from the internal one. Transcription now initiates at position 146 rather than position 56 relative to the genome 3' end. Under these conditions, it was found that the frequency with which mRNA synthesis initiates depends, in an inverse fashion, on the strength of the external replication promoter. It was also found that the sequences essential for replication are not required for basic mRNA synthesis as long as there is an external replication promoter at which viral RNA polymerase can enter the nucleocapsid template. The manner in which transcription and replication initiations influence each other is discussed.
authors.affiliation: Department of Microbiology and Molecular Medicine, University of Geneva Medical School, CMU, 1 rue Michel-Servet, CH-1211 Geneva 4, Switzerland.
authors.forename: Diane
authors.initials: D
authors.lastname: Vulliémoz
authors.affiliation: Department of Microbiology and Molecular Medicine, University of Geneva Medical School, CMU, 1 rue Michel-Servet, CH-1211 Geneva 4, Switzerland.
authors.forename: Samuel
authors.initials: S
authors.lastname: Cordey
authors.affiliation: Department of Microbiology and Molecular Medicine, University of Geneva Medical School, CMU, 1 rue Michel-Servet, CH-1211 Geneva 4, Switzerland.
authors.forename: Geneviève
authors.initials: G
authors.lastname: Mottet-Osman
authors.affiliation: Department of Microbiology and Molecular Medicine, University of Geneva Medical School, CMU, 1 rue Michel-Servet, CH-1211 Geneva 4, Switzerland.
authors.forename: Laurent
authors.initials: L
authors.lastname: Roux
mesh_terms: D020413:3' Untranslated Regions; D001483:Base Sequence; D049452:Green Fluorescent Proteins / Q000096:biosynthesis; D008969:Molecular Sequence Data; D011401:Promoter Regions, Genetic / Q000502:physiology*; D012333:RNA, Messenger / Q000096:biosynthesis; D012367:RNA, Viral / Q000096:biosynthesis; D029082:Sendai virus / Q000235:genetics*; D024363:Transcription Initiation Site; D014779:Virus Replication / Q000235:genetics*
chemical_list: D020413:3' Untranslated Regions; D012333:RNA, Messenger; D012367:RNA, Viral; D049452:Green Fluorescent Proteins