Study on the molecular mechanisms of sperm motility in chordates

2022 Fiscal Year Final Research Report

• Project/Area Number: 20K06715
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 44040:Morphology and anatomical structure-related
• Research Institution: The University of Tokyo
• Principal Investigator: Yoshida Manabu 東京大学, 大学院理学系研究科(理学部), 准教授 (60301785)
• Project Period (FY): 2020-04-01 – 2023-03-31
• Keywords: 受精 / 精子 / 鞭毛運動

Outline of Final Research Achievements

In this study, we analyzed the Ca2+-signaling system that regulates chordate sperm motility.
First, we found a testis-specific splice variant in the ascidian plasma membrane Ca2-ATPase (PMCA). Sperm attractants recognize species-specific extracellular sequences of PMCA, and intracellular testis-specific sequences may be involved in sperm activation and chemotaxis .
We also analyzed the gene expression profile of the pufferfish by RNAseq analysis. The results showed that 62 Ca2+-signaling genes were upregulated in the late stage of spermatogenesis. These included many glutamate receptors, voltage-gated Ca2+ channels, PMCA, and Na+-K+/Ca2+ exchangers.

Free Research Field

生殖生物学・細胞生理化学

Academic Significance and Societal Importance of the Research Achievements

精子運動調節の分子機構は哺乳類を中心に解析がすすめられ、精子特異的Ca2+チャネルCatsperが唯一のCa2+チャネルとして働くことが知られている。しかしCatSperは脊椎動物でも無顎類、真骨魚類、両生類、鳥類で欠失している。本研究は真骨魚類をもちいた初めての精子運動調節におけるCa2+シグナル系の解析であり、精子運動調節の普遍性と進化の理解に大きく寄与すると自負する。また、将来的な男性不妊治療や繁殖技術の改良にむけたシーズとなることが期待される。