Elucidating the molecular basis of evolution of gamete fusion mechanism associated with the establishment of male-female gamete dimorphism

2015 Fiscal Year Final Research Report

• Project/Area Number: 25891009
• Research Category: Grant-in-Aid for Research Activity Start-up
• Allocation Type: Single-year Grants
• Research Field: Evolutionary biology
• Research Institution: The University of Tokyo
• Principal Investigator: Kawai-Toyooka Hiroko 東京大学, 理学系研究科, 特任研究員 (00442997)
• Project Period (FY): 2013-08-30 – 2016-03-31
• Keywords: 配偶子融合 / 群体性ボルボックス目 / ボルボックス系列 / 異型配偶化 / GCS1 / ゴニウム / 有性生殖

Outline of Final Research Achievements

Oogamy, which involves the fusion of a large non-motile female gamete (egg) and a small motile male gamete (sperm), appears to have successively evolved from isogamy (equal sized gametes) and anisogamy (large and small gametes). To elucidate the evolutionary transition of the gamete fusion mechanism , this project focused on the volvocine green algae, because they comprise a series of genera with all the three modes of gamete fusion. Using isogamous volvocine Gonium, this project first focus on the gamete fusion mechanism itself and clarified the cellular basis for male-specific action of the gamete fusion protein GCS1, and then established a method to isolate mating structures from both sex gametes. Moreover, this project identified an orthologous gene of isogamous gamete adhesion protein FUS1 in anisogamous Eudorina, providing insight into the molecular basis of evolution of gamete fusion mechanism associated with the establishment of male-female gamete dimorphism.

Free Research Field

細胞生物学