Genetic mechanism and evolution of achiasmy in Drosophila

2019 Fiscal Year Final Research Report

• Project/Area Number: 17K19430
• Research Category: Grant-in-Aid for Challenging Research (Exploratory)
• Allocation Type: Multi-year Fund
• Research Field: Ecology and Evolution (including anthropology), and related fields
• Research Institution: Tokyo Metropolitan University
• Principal Investigator: Tamura Koichiro 首都大学東京, 理学研究科, 教授 (00254144)
• Project Period (FY): 2017-06-30 – 2020-03-31
• Keywords: 減数分裂組換え / アキアズミー / 染色体不分離 / ショウジョウバエ / ネオ性染色体

Outline of Final Research Achievements

In Drosophila, meiotic recombination does not generally occur in males. However, it has been known that meiotic recombination occurs in D. nasuta males, whereas it does not occur in its sibling species, D. albomicans. In this research project, examining male meiotic recombination in their F1 hybrids, we found that meiotic recombination does not occur in the F1 hybrids, suggesting a genetically dominant mechanism of suppressing meiotic recombination in males. We also found that sex chromosome disjunction occurs at a high frequency in the hybrid males.

Free Research Field

分子進化遺伝学

Academic Significance and Societal Importance of the Research Achievements

減数分裂組換えには、ゲノムの修復や遺伝的多様性の創出・維持などの生物学的意義があるが、性分化のための性染色体の進化を阻害する副作用もある。多くの生物群では、X染色体とY染色体のような異形性染色体を持つ性でのみ減数分裂組換えを抑制するアキアズミーによって減数分裂組換えと性染色体進化のジレンマを解決している。本研究の学術的意義はアキアズミーの分子機構の解明によって性染色体の進化の仕組みの理解を深めることにある。