Genetic basis of speciation process driven by adaptation to new oviposition substrate

2021 Fiscal Year Final Research Report

• Project/Area Number: 19H03276
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Single-year Grants
• Section: 一般
• Review Section: Basic Section 45020:Evolutionary biology-related
• Research Institution: Tokyo Metropolitan University
• Principal Investigator: Takahashi Aya 東京都立大学, 理学研究科, 准教授 (90370121)
• Co-Investigator(Kenkyū-buntansha): 上村 佳孝 慶應義塾大学, 商学部(日吉), 准教授 (50366952) ; 野澤 昌文 東京都立大学, 理学研究科, 准教授 (50623534)
• Project Period (FY): 2019-04-01 – 2022-03-31
• Keywords: 種分化 / 交尾器 / 外部生殖器 / ショウジョウバエ / 遺伝子マッピング / ゲノムシークエンス / 生殖的隔離 / 産卵

Outline of Final Research Achievements

Not like most other Drosophila species, Drosophila suzukii lays its eggs into firm ripening fruits. Its ovipositor is elongated and have many bristles lined up on the edge to pierce the skin of those fruits. This morphological evolution affects not only egg-laying, but also the spatial configurations of male and female genitalia during copulation resulting in the reproductive isolation caused by the mechanical mismatch during interspecific mating. The morphology involved in such form of reproductive isolation between D. suzukii and its closely related species D. subpulchrella was investigated in detail. The genetic analyses of those morphological trait revealed that the DNA sequence regions with frequent structural changes were involved in such morphological evolution. Furthermore, strong candidate genes that may have been responsible for the genetic changes occurred between the two species were also identified.

Free Research Field

進化遺伝学

Academic Significance and Societal Importance of the Research Achievements

本研究では、オウトウショウジョウバエ(Drosophila suzukii)とその近縁種D. subpulchrellaを使って、生物の種が分化していく際に種間での交配を妨げるような生殖器形態の進化が、ゲノム中の構造的な変化が激しい領域に起きる突然変異によって進んできたことが明らかとなった。この成果は、生物の進化を理解する上で、種が分化していく仕組みや昆虫などの動物で生殖器の形が速く進化していることの原因を探究していくために重要な情報となる。