title: A dsRNA mycovirus, Magnaporthe oryzae chrysovirus 1-B, suppresses vegetative growth and development of the rice blast fungus.
abstract: 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.
authors: Laboratories of Molecular and Cellular Biology, Graduate School of Agriculture, Tokyo University of Agriculture and Technology, 3-5-8 Saiwaicho, Fuchu, Tokyo 183-8509, Japan.
authors: Syun-ichi
authors: S
authors: Urayama
authors: Hirofumi
authors: H
authors: Sakoda
authors: Ryoko
authors: R
authors: Takai
authors: Yu
authors: Y
authors: Katoh
authors: Tuong
authors: T
authors: Minh Le
authors: Toshiyuki
authors: T
authors: Fukuhara
authors: Tsutomu
authors: T
authors: Arie
authors: Tohru
authors: T
authors: Teraoka
authors: Hiromitsu
authors: H
authors: Moriyama
mesh_terms: D001483:Base Sequence; D020082:Magnaporthe / Q000254:growth & development* / Q000821:virology*; D008969:Molecular Sequence Data; D012275:Oryza / Q000382:microbiology*; D010802:Phylogeny; D010935:Plant Diseases / Q000382:microbiology*; D012328:RNA Viruses / Q000235:genetics / Q000302:isolation & purification* / Q000502:physiology*; D012330:RNA, Double-Stranded / Q000235:genetics / Q000378:metabolism; D012367:RNA, Viral / Q000235:genetics / Q000378:metabolism
chemical_list: D012330:RNA, Double-Stranded; D012367:RNA, Viral
keywords: Attenuation; Magnaporthe oryzae; Multi-segmented mycovirus; Mycovirus; Tentative chrysovirus; Virus-induced growth inhibition; dsRNA virus