+1 Recommend
1 collections
      • Record: found
      • Abstract: found
      • Article: found
      Is Open Access

      ICTV Virus Taxonomy Profile: Chrysoviridae


      Read this article at

          There is no author summary for this article yet. Authors can add summaries to their articles on ScienceOpen to make them more accessible to a non-specialist audience.


          The Chrysoviridae is a family of small, isometric, non-enveloped viruses (40 nm in diameter) with segmented dsRNA genomes (typically four segments). The genome segments are individually encapsidated and together comprise 11.5–12.8 kbp. The single genus Chrysovirus includes nine species. Chrysoviruses lack an extracellular phase to their life cycle; they are transmitted via intracellular routes within an individual during hyphal growth, in asexual or sexual spores, or between individuals via hyphal anastomosis. There are no known natural vectors for chrysoviruses. This is a summary of the International Committee on Taxonomy of Viruses (ICTV) Report on the taxonomy of the Chrysoviridae, which is available at www.ictv.global/report/chrysoviridae.

          Related collections

          Most cited references9

          • Record: found
          • Abstract: found
          • Article: not found

          Identification of the motifs within the tobacco mosaic virus 5'-leader responsible for enhancing translation.

          The leader (called omega) of tobacco mosaic virus RNA enhances translation in both eukaryotes and prokaryotes. Although little secondary structure is predicted to exist within omega, the primary sequence of the 68 base leader is highly organized. Three copies of an eight base direct repeat and a (CAA)n region represent the two motifs found in the leaders of many TMV strains, and together these comprise 72% of omega. In previous deletion studies, no mutants exhibited loss-of-function, suggesting that functional redundancy exists within omega. We report here that a more comprehensive deletion analysis identified the motifs involved in translational enhancement. In a separate approach, oligonucleotides containing the sequence of each motif were used to construct leaders that varied in the number and configuration of the motifs. beta-Glucuronidase mRNA constructs containing these mutant leaders were synthesized in vitro and their translational efficiency measured in vivo following mRNA delivery to carrot protoplasts via electroporation. A combination of one copy of the 8 base direct repeat and a 25 base (CAA)n region was identified as the core regulatory element, although the (CAA)n motif is more critical. Two copies of the (CAA)n region are sufficient to confer a high level of enhancement and a leader composed of multiple copies of the direct repeat is moderately enhancing. Thus, these two motifs are functionally redundant.
            • Record: found
            • Abstract: found
            • Article: not found

            A dsRNA mycovirus, Magnaporthe oryzae chrysovirus 1-B, suppresses vegetative growth and development of the rice blast fungus.

            A double-stranded RNA (dsRNA) mycovirus was found in isolate S-0412-II 2a of the rice blast fungus Magnaporthe oryzae. Sequence analysis of the five dsRNA segments (dsRNA1 through dsRNA5) revealed that this mycovirus is closely related to Magnaporthe oryzae chrysovirus 1-A (MoCV1-A), tentatively classified as a member of the Chrysoviridae; therefore, it was named Magnaporthe oryzae chrysovirus 1-B (MoCV1-B). Virus particles were spherical and composed of the ORF1, ORF3 and ORF4 proteins. MoCV1-B-infected isolate S-0412-II 2a showed a more severe impaired phenotype than the MoCV1-A-infected isolate. In a virus-cured isolate, normal growth was restored, implied that MoCV1-B could be involved in this observed phenotype. An unanticipated result was the occurrence of a fungal isolate lacking dsRNA5. The nonessential dsRNA5 had higher sequence identity (96%) with dsRNA5 of MoCV1-A than with the other dsRNA segments (71-79%), indicating that dsRNA5 could be a portable genomic element between MoCV1-A and MoCV1-B.
              • Record: found
              • Abstract: found
              • Article: not found

              Molecular characterization of Penicillium chrysogenum virus: reconsideration of the taxonomy of the genus Chrysovirus.

              Molecular cloning and complete nucleotide sequencing of Penicillium chrysogenum virus (PcV) dsRNAs indicated that PcV virions contained four dsRNA segments with sizes of 3562, 3200, 2976 and 2902 bp. Each dsRNA segment had unique sequences and contained a single large open reading frame (ORF). In vitro translation of transcripts derived from full-length cDNA clones of PcV dsRNAs yielded single products of sizes similar to those predicted from the deduced amino acid sequences of the individual ORFs. Sequence similarity searches revealed that dsRNA1 encodes a putative RNA-dependent RNA polymerase. In this study, it was determined that dsRNA2 encodes the major capsid protein and that p4, encoded by dsRNA4, is virion-associated as a minor component. All four dsRNAs of PcV, like the genomic segments of viruses with multipartite genomes, were found to have extended regions of highly conserved terminal sequences at both ends. In addition to the strictly conserved 5'-terminal 10 nt, a second region consisting of reiteration of the sequence CAA was found immediately upstream of the AUG initiator codon. These (CAA)(n) repeats are reminiscent of the translational enhancer elements of tobamoviruses. The 3'-terminal 14 nt were also strictly conserved. As PcV and related viruses with four dsRNA segments (genus Chrysovirus) have not been previously characterized at the molecular level, they were provisionally classified in the family Partitiviridae, comprising viruses with bipartite genomes. This study represents the first report on molecular characterization of a chrysovirus and the results suggest the creation of a new family of mycoviruses with multipartite dsRNA genomes to accommodate PcV and related viruses.

                Author and article information

                J Gen Virol
                J. Gen. Virol
                The Journal of General Virology
                Microbiology Society
                January 2018
                18 December 2017
                18 December 2017
                : 99
                : 1
                : 19-20
                [ 1]Department of Plant Pathology, University of Kentucky , Lexington, KY 40546, USA
                [ 2]Department of Structure of Macromolecules Centro Nacional Biotecnología/CSIC, Campus de Cantoblanco , 28049 Madrid, Spain
                [ 3]Department of Biological and Environmental Sciences, School of Life and Medical Sciences, University of Hertfordshire , Hatfield, AL10 9AB, UK
                [ 4]Department of Plant Biology and Pathology, School of Environmental and Biological Sciences Rutgers, The State University of New Jersey , New Brunswick, NJ, USA
                [ 5]College of Plant Science and Technology, Huazhong Agricultural University , Wuhan 430070, Hubei Province, PR China
                [ 6]Division of Biological Sciences, Chonbuk National University , Dukjindong 664-14, Jeonju, Chonbuk 561-756, Republic of Korea
                [ 7]Laboratories of Molecular and Cellular Biology, Tokyo University of Agriculture and Technology , 3-5-8 Saiwaicho, Fuchu, Tokyo 183-8509, Japan
                Author notes
                *Correspondence: Said A. Ghabrial, saghab00@ 123456uky.edu

                This is an open access article under the terms of the Creative Commons Attribution 4.0 International License, which permits unrestricted use, distribution and reproduction in any medium, provided the original author and source are credited.

                : 29 November 2017
                : 04 December 2017
                Funded by: Wellcome Trust (GB)
                Award ID: WT108418AIA
                ICTV Virus Taxonomy Profiles
                Fungal Viruses
                Custom metadata

                Microbiology & Virology
                chrysoviridae,taxonomy,ictv report,penicillium chrysogenum virus,aspergillus fumigatus chrysovirus,helminthosporium victoriae virus 145s


                Comment on this article