title: X-ray structure and activities of an essential Mononegavirales L-protein domain.
abstract: The L protein of mononegaviruses harbours all catalytic activities for genome replication and transcription. It contains six conserved domains (CR-I to -VI; Fig. 1a). CR-III has been linked to polymerase and polyadenylation activity, CR-V to mRNA capping and CR-VI to cap methylation. However, how these activities are choreographed is poorly understood. Here we present the 2.2-Å X-ray structure and activities of CR-VI+, a portion of human Metapneumovirus L consisting of CR-VI and the poorly conserved region at its C terminus, the +domain. The CR-VI domain has a methyltransferase fold, which besides the typical S-adenosylmethionine-binding site ((SAM)P) also contains a novel pocket ((NS)P) that can accommodate a nucleoside. CR-VI lacks an obvious cap-binding site, and the (SAM)P-adjoining site holding the nucleotides undergoing methylation ((SUB)P) is unusually narrow because of the overhanging +domain. CR-VI+ sequentially methylates caps at their 2'O and N7 positions, and also displays nucleotide triphosphatase activity.
authors.affiliation: Division of Structural Biology, Wellcome Trust Centre for Human Genetics, Oxford OX3 7BN, UK.
authors.forename: Guido C
authors.initials: GC
authors.lastname: Paesen
authors.affiliation: AFMB, CNRS, Aix-Marseille University, UMR 7257, Case 925, 163 Avenue de Luminy, 13288 Marseille, France.
authors.forename: Axelle
authors.initials: A
authors.lastname: Collet
authors.affiliation: Department of Nucleic Acids, IBMM, UMR 5247, CNRS, Université Montpellier, ENSCM, Campus Triolet, Place E. Bataillon, 34095 Montpellier, France.
authors.forename: Corinne
authors.initials: C
authors.lastname: Sallamand
authors.affiliation: Department of Nucleic Acids, IBMM, UMR 5247, CNRS, Université Montpellier, ENSCM, Campus Triolet, Place E. Bataillon, 34095 Montpellier, France.
authors.forename: Françoise
authors.initials: F
authors.lastname: Debart
authors.affiliation: Department of Nucleic Acids, IBMM, UMR 5247, CNRS, Université Montpellier, ENSCM, Campus Triolet, Place E. Bataillon, 34095 Montpellier, France.
authors.forename: Jean-Jacques
authors.initials: JJ
authors.lastname: Vasseur
authors.affiliation: AFMB, CNRS, Aix-Marseille University, UMR 7257, Case 925, 163 Avenue de Luminy, 13288 Marseille, France.
authors.forename: Bruno
authors.initials: B
authors.lastname: Canard
authors.affiliation: AFMB, CNRS, Aix-Marseille University, UMR 7257, Case 925, 163 Avenue de Luminy, 13288 Marseille, France.
authors.forename: Etienne
authors.initials: E
authors.lastname: Decroly
authors.affiliation: Division of Structural Biology, Wellcome Trust Centre for Human Genetics, Oxford OX3 7BN, UK.|Diamond Light Source Limited, Harwell Science and Innovation Campus, Didcot OX11 0DE, UK.
authors.forename: Jonathan M
authors.initials: JM
authors.lastname: Grimes
mesh_terms: D000818:Animals; D001665:Binding Sites; D002855:Chromatography, Thin Layer; D003460:Crystallization; D018360:Crystallography, X-Ray; D029121:Metapneumovirus / Q000378:metabolism*; D008745:Methylation; D018096:Mononegavirales / Q000378:metabolism; D017434:Protein Structure, Tertiary; D012313:RNA / Q000378:metabolism*; D012315:RNA Caps / Q000378:metabolism*; D012324:RNA-Dependent RNA Polymerase / Q000737:chemistry / Q000378:metabolism; D012436:S-Adenosylmethionine / Q000378:metabolism*; D061987:Sf9 Cells; D018411:Spodoptera; D014764:Viral Proteins / Q000737:chemistry / Q000378:metabolism
chemical_list: D012315:RNA Caps; D014764:Viral Proteins; D012313:RNA; D012436:S-Adenosylmethionine; D012324:RNA-Dependent RNA Polymerase