Analysis of double-strand RNA virus replication(Fostering Joint International Research)

2019 Fiscal Year Final Research Report

• Project/Area Number: 15KK0281
• Research Category: Fund for the Promotion of Joint International Research (Fostering Joint International Research)
• Allocation Type: Multi-year Fund
• Research Field: Veterinary medical science
• Research Institution: Kobe University
• Principal Investigator: Matsuo Eiko 神戸大学, 農学研究科, 助教 (40620878)
• Project Period (FY): 2016 – 2019
• Keywords: 二本鎖RNAウイルス / 遺伝子改良法 / VP6 / ウイルス封入体

Outline of Final Research Achievements

Ibaraki virus (IBAV) is a member of the epizootic hemorrhagic disease virus serogroup, which belongs to the Orbivirus genus of the Reoviridae family. Previously, we developed reverse genetics system (RG) for IBAV, to clarify the molecular mechanism of orbivirus replication. We also found several cell lines, in which, the replication of IBAV was suppressed. Here, using newly developed plasmid-based RG for two other orbiviruses, bluetongue virus (BTV) and Muko virus (MUV), fluorescent-labeled (FL-) BTV and MUV were generated. Co-infection assay using FL-BTV and FL-MUV together with FL-IBAV revealed the fuzzy self-recognition mechanisms in virus inclusion body. In addition, we demonstrated that some mechanisms of a unique protein, VP6, were shared among orbiviruses. Further, the replication of midge-borne orbiviruses, not tick-bone virus, was likely to be suppressed in several cell lines. We also tried to reveal VP6 structure using Cryo-EM technique, which was unfortunately failed.

Free Research Field

分子ウイルス学

Academic Significance and Societal Importance of the Research Achievements

これまで、同属他種のウイルスを、全く同じ条件で同時に比較した論文は少ない。また、同種の異なる株のウイルスの共感染時に細胞内で起こる現象については報告があるが、同属異種のウイルスが共感染した時に何が起こっているかについて、その分子機構を調べた報告はない。二本鎖RNAウイルスは医学的・獣医学的領域で重要なものも多いにも関わらず、その分子生物学的発見はやや後進的とみられることがあるが、本研究で得られた知見には完全に新規の発見が含まれている。また、本研究成果は、治療法やワクチン開発にも大いに貢献できると期待され、学術的だけでなく社会的にも非常に意義があると考えられる。