LIVIVO - The Search Portal for Life Sciences

zur deutschen Oberfläche wechseln
Advanced search

Search results

Result 1 - 2 of total 2

Search options

  1. Article ; Online: GDP polyribonucleotidyltransferase domain of vesicular stomatitis virus polymerase regulates leader-promoter escape and polyadenylation-coupled termination during stop-start transcription.

    Minako Ogino / Todd J Green / Tomoaki Ogino

    PLoS Pathogens, Vol 18, Iss 2, p e

    2022  Volume 1010287

    Abstract: The unconventional mRNA capping enzyme (GDP polyribonucleotidyltransferase, PRNTase) domain of the vesicular stomatitis virus (VSV) L protein possesses a dual-functional "priming-capping loop" that governs terminal de novo initiation for leader RNA ... ...

    Abstract The unconventional mRNA capping enzyme (GDP polyribonucleotidyltransferase, PRNTase) domain of the vesicular stomatitis virus (VSV) L protein possesses a dual-functional "priming-capping loop" that governs terminal de novo initiation for leader RNA synthesis and capping of monocistronic mRNAs during the unique stop-start transcription cycle. Here, we investigated the roles of basic amino acid residues on a helix structure directly connected to the priming-capping loop in viral RNA synthesis and identified single point mutations that cause previously unreported defective phenotypes at different steps of stop-start transcription. Mutations of residue R1183 (R1183A and R1183K) dramatically reduced the leader RNA synthesis activity by hampering early elongation, but not terminal de novo initiation or productive elongation, suggesting that the mutations negatively affect escape from the leader promoter. On the other hand, mutations of residue R1178 (R1178A and R1178K) decreased the efficiency of polyadenylation-coupled termination of mRNA synthesis at the gene junctions, but not termination of leader RNA synthesis at the leader-to-N-gene junction, resulting in the generation of larger amounts of aberrant polycistronic mRNAs. In contrast, both the R1183 and R1178 residues are not essential for cap-forming activities. The R1183K mutation was lethal to VSV, whereas the R1178K mutation attenuated VSV and triggered the production of the polycistronic mRNAs in infected cells. These observations suggest that the PRNTase domain plays multiple roles in conducting accurate stop-start transcription beyond its known role in pre-mRNA capping.
    Keywords Immunologic diseases. Allergy ; RC581-607 ; Biology (General) ; QH301-705.5
    Subject code 572
    Language English
    Publishing date 2022-02-01T00:00:00Z
    Publisher Public Library of Science (PLoS)
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

    More links

    Kategorien

  2. Article ; Online: The Rabies Virus L Protein Catalyzes mRNA Capping with GDP Polyribonucleotidyltransferase Activity

    Minako Ogino / Naoto Ito / Makoto Sugiyama / Tomoaki Ogino

    Viruses, Vol 8, Iss 5, p

    2016  Volume 144

    Abstract: The large (L) protein of rabies virus (RABV) plays multiple enzymatic roles in viral RNA synthesis and processing. However, none of its putative enzymatic activities have been directly demonstrated in vitro. In this study, we expressed and purified a ... ...

    Abstract The large (L) protein of rabies virus (RABV) plays multiple enzymatic roles in viral RNA synthesis and processing. However, none of its putative enzymatic activities have been directly demonstrated in vitro. In this study, we expressed and purified a recombinant form of the RABV L protein and verified its guanosine 5′-triphosphatase and GDP polyribonucleotidyltransferase (PRNTase) activities, which are essential for viral mRNA cap formation by the unconventional mechanism. The RABV L protein capped 5′-triphosphorylated but not 5′-diphosphorylated RABV mRNA-start sequences, 5′-AACA(C/U), with GDP to generate the 5′-terminal cap structure G(5′)ppp(5′)A. The 5′-AAC sequence in the substrate RNAs was found to be strictly essential for RNA capping with the RABV L protein. Furthermore, site-directed mutagenesis showed that some conserved amino acid residues (G1112, T1170, W1201, H1241, R1242, F1285, and Q1286) in the PRNTase motifs A to E of the RABV L protein are required for cap formation. These findings suggest that the putative PRNTase domain in the RABV L protein catalyzes the rhabdovirus-specific capping reaction involving covalent catalysis of the pRNA transfer to GDP, thus offering this domain as a target for developing anti-viral agents.
    Keywords rabies virus ; L protein ; mRNA capping ; GDP polyribonucleotidyltransferase ; Microbiology ; QR1-502 ; Science ; Q
    Subject code 570
    Language English
    Publishing date 2016-05-01T00:00:00Z
    Publisher MDPI AG
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

    More links

    Kategorien

To top