title: Rift Valley fever virus L segment: correction of the sequence and possible functional role of newly identified regions conserved in RNA-dependent polymerases.
abstract: The sequence of Rift Valley fever virus L segment that we published in a previous paper was erroneous in the 3'-terminal region of the antigenomic RNA molecule. Here, we have shown that the L segment is in fact 6404 nucleotides long and encodes a polypeptide of 237.7K in the viral complementary sense. Sequence comparisons performed between the RNA-dependent RNA polymerases of 22 negative-stranded RNA viruses revealed the existence of two novel regions located at the amino termini of the proteins and conserved only in the polymerases of bunya- and arenaviruses. In the region conserved in all RNA-dependent polymerases, corresponding to the so-called 'polymerase module', we identified a new motif, designated premotif A, common to all RNA-dependent polymerases, as well as amino acids located in the region between motifs preA and A which are strictly conserved for segmented negative-stranded RNA viruses. Using the recently released coordinates of human immunodeficiency virus reverse transcriptase and the alignment between all RNA-dependent polymerases in the 'polymerase module', we have determined the position of the conserved residues in these polymerases and discuss their possible functions in light of the available structural information.
authors.affiliation: Laboratoire des Bunyaviridés, CNRS URA 545, Institut Pasteur, Paris, France.
authors.forename: R
authors.initials: R
authors.lastname: Müller
authors.forename: O
authors.initials: O
authors.lastname: Poch
authors.forename: M
authors.initials: M
authors.lastname: Delarue
authors.forename: D H
authors.initials: DH
authors.lastname: Bishop
authors.forename: M
authors.initials: M
authors.lastname: Bouloy
mesh_terms: D000595:Amino Acid Sequence; D018050:Arenavirus / Q000235:genetics; D003001:Cloning, Molecular; D005814:Genes, Viral; D054303:HIV Reverse Transcriptase; D008969:Molecular Sequence Data; D016851:Orthobunyavirus / Q000235:genetics; D017434:Protein Structure, Tertiary; D012367:RNA, Viral / Q000235:genetics; D012324:RNA-Dependent RNA Polymerase / Q000235:genetics*; D012194:RNA-Directed DNA Polymerase / Q000737:chemistry; D012296:Rift Valley fever virus / Q000235:genetics*; D016415:Sequence Alignment; D017386:Sequence Homology, Amino Acid; D013329:Structure-Activity Relationship; D015678:Viral Structural Proteins / Q000235:genetics
chemical_list: D012367:RNA, Viral; D015678:Viral Structural Proteins; D012324:RNA-Dependent RNA Polymerase; D054303:HIV Reverse Transcriptase; D012194:RNA-Directed DNA Polymerase