Basic study for identification of common FMDV, CSFV IRES factors and its application

2023 Fiscal Year Final Research Report

• Project/Area Number: 20H03164
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Single-year Grants
• Section: 一般
• Review Section: Basic Section 42030:Animal life science-related
• Research Institution: Kagoshima University
• Principal Investigator: Kohara Kyoko 鹿児島大学, 農水産獣医学域獣医学系, 教授 (20225478)
• Co-Investigator(Kenkyū-buntansha): 岡林 環樹 宮崎大学, 農学部, 教授 (10359995) ; 迫田 義博 北海道大学, 獣医学研究院, 教授 (40333637)
• Project Period (FY): 2020-04-01 – 2023-03-31
• Keywords: FMDV / CSFV / IRES / shRNA / PYC / PKD1L3 / USP31 / KOマウス

Outline of Final Research Achievements

The viruses that cause foot-and-mouth disease and swine fever (FMDV, CSFV) have positive-strand RNA in their genomes, and have a sequence (IRES) in the 5' untranslated region (5'UTR) that is internally recognized by ribosomes and initiates translation. We established cell lines with dicistronic vectors that can measure these IRES activities, and constructed lentiviral vectors loaded with siRNA and shRNA that can act on sequences conserved in the seven FMDV serotypes, and were able to suppress the activity for over two weeks. . We also established a CSFV-IRES target shRNA expression vector, which made it possible to suppress IRES activity and CSFV replication. Furthermore, we found that French pine sap pycnojunol (PYC) inhibits these IRES activities, and comprehensive expression analysis of target host factors revealed that they were PKD1L3 and USP31. Furthermore, we established KO mice for PKD1L3 and USP31 to obtain the knowledge necessary to establish FMDV and CSFV-resistant animals.

Free Research Field

ウイルス学

Academic Significance and Societal Importance of the Research Achievements

口蹄疫は、日本での流行はコントロールされ、現在清浄国となっているが、未だ近隣諸国での発生が報告され、疾病の侵入防止には、予断を許さない。ワクチンは、口蹄疫の血清型間の交差有効性が低いという問題があり、ワクチンの使用に伴い清浄国ではなくなる。一方で、豚熱は国内では26年ぶりに岐阜県で発生後流行が拡大し、現在に至るまで制圧されていない。有効なワクチンは存在するがワクチン使用に伴って清浄国と認められなくなり、抗ウイルス薬は開発されておらず、野生動物のイノシシも感染感受性がある事等が、豚熱の制御を困難にしている。以上の様に、侵襲が予測できない動物感染症に対し、抵抗性家畜の開発は有効と期待できる。