Reverse genetics approach for mechanism of diarrhea induced by rotavirus infection

• Project/Area Number: 18K07145
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 49060:Virology-related
• Research Institution: Osaka University
• Principal Investigator: Kanai Yuta 大阪大学, 微生物病研究所, 講師 (80506501)
• Project Period (FY): 2018-04-01 – 2021-03-31
• Project Status: Completed (Fiscal Year 2020)
• Budget Amount: ¥4,550,000 (Direct Cost: ¥3,500,000、Indirect Cost: ¥1,050,000); Fiscal Year 2020: ¥1,560,000 (Direct Cost: ¥1,200,000、Indirect Cost: ¥360,000); Fiscal Year 2019: ¥1,560,000 (Direct Cost: ¥1,200,000、Indirect Cost: ¥360,000); Fiscal Year 2018: ¥1,430,000 (Direct Cost: ¥1,100,000、Indirect Cost: ¥330,000)
• Keywords: ウイルス / 下痢症 / 治療 / ロタウイルス / リバースジェネティクス / ワクチン

Outline of Final Research Achievements

We investigated the diarrhea inducing ability of recombinant rotavirus SA11 strain (rSA11) with mutant NSP4 protein. rSA11 mutant which had amino acid mutations in C-terminal region of NSP4 induced less diarrhea in 4-day-old mouse pups. By serial passages of wild-type SA11 strain in mouse for total 10 times, mouse-adapted rotavirus, SA11m strain which showed higher replication in mouse intestine in comparison to wild-type SA11 was obtained. Immortalized cell lines derived from mouse intestinal cells were established. The infections of SA11m in mouse inoculated with antibiotics were inhibited suggesting the involvement of intestinal microbiota to rotavirus infections.

Academic Significance and Societal Importance of the Research Achievements

ロタウイルス下痢の理解に寄与するロタウイルスは5歳以下の乳幼児に重篤な下痢症を引き起こし、全世界で毎年20万人前後がロタウイルス感染により亡くなっている。本研究ではロタウイルスNSP4タンパク質の特定のアミノ酸が下痢発症に関与していることを明らかにしたことから、これまでに記録されているロタウイルス臨床株の遺伝子配列を比較することで下痢発症の予測の可能性を示した。さらにサルロタウイルスのマウス感染モデルの構築したことから、ワクチンや抗ウイルス薬の試験が可能になる。

Research Products

• [Journal Article] Generation of recombinant rotaviruses encoding a split NanoLuc peptide tag (2021)
  • Author(s): Pimfhun P, Kanai Y, Kawagishi T, Nouda R, Nurdin J, Yamasaki M, Nomura K, Tina L, Kobayashi T
  • Journal Title: Biochemical and Biophysical Research Communications Volume: 534 Pages: 740-746
  • DOI: 10.1016/j.bbrc.2020.11.007
  • Peer Reviewed
• [Journal Article] Reverse Genetics Approach for Developing Rotavirus Vaccine Candidates Carrying VP4 and VP7 Genes Cloned from Clinical Isolates of Human Rotavirus (2021)
  • Author(s): Kanai Y, Onishi M, Kawagishi T, Pimfhun P, Nurdin J, Nouda R, Yamasaki M, Tina L, Pattara K, Okitsu S, Hayakawa S, Ebina H, Ushijima H, Kobayashi T
  • Journal Title: Journal of Virology Volume: 95 Issue: 2
  • DOI: 10.1128/jvi.01374-20
  • Peer Reviewed / Int'l Joint Research
• [Journal Article] Development of Stable Rotavirus Reporter Expression Systems (2019)
  • Author(s): Kanai Y, Kawagishi T, Nouda R, Onishi M, Pannacha P, Nurdin JA, Nomura K, Matsuura Y, Kobayashi T.
  • Journal Title: Journal of Virology Volume: 93 Issue: 4
  • DOI: 10.1128/jvi.01774-18
  • Peer Reviewed
• [Presentation] Reverse genetics approach for the development of rotavirus vaccine and viral vector (2020)
  • Author(s): Kanai Y
  • Organizer: 広東省胸部疾病学会医学検試専業委員会2020 年会及胸部疾病検試診断技術新進展学習班
  • Invited