Analysis of vitellogenesis in fish using genome genome editing technology

2023 Fiscal Year Final Research Report

• Project/Area Number: 21K05764
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 40040:Aquatic life science-related
• Research Institution: Hokkaido University
• Principal Investigator: Todo Takashi 北海道大学, 水産科学研究院, 教授 (60303111)
• Co-Investigator(Kenkyū-buntansha): 平松 尚志 北海道大学, 水産科学研究院, 准教授 (10443920)
• Project Period (FY): 2021-04-01 – 2024-03-31
• Keywords: 卵形成 / 卵成長 / 卵黄形成 / メダカ / 中性脂質 / タンパク質 / リポタンパク質 / ゲノム編集

Outline of Final Research Achievements

In this study, we aimed to clarify the molecular mechanisms underlying accumulation of neutral lipids (lipid droplets) and yolk proteins (yolk granules) into teleost oocytes as yolk materials. Japanese medaka was selected as the research model, and the functions of several factors which are expected to involved in the accumulation of yolk materials, was examined through the analyses of their expression patterns in ovarian follicles and the gene-editing technology. As the results, it was shown that lipoprotein lipase expressed in the ovarian follicle cells, a key enzyme of very low density lipoprotein which is the major carrier of neutral lipids to oocyte lipid droplets, plays an important role on the formation of lipid droplets in oocytes. In addition, for the accumulation of yolk proteins, it was suggested that multiple types of lipoprotein receptors have each different and specific role on the uptake of the multiple types of yolk protein precursors.

Free Research Field

魚類繁殖生理学

Academic Significance and Societal Importance of the Research Achievements

本研究は、魚類の卵成長や胚発生、仔稚魚の成長に必要不可欠な魚類の卵黄形成機構について、中性脂質と卵黄タンパク質の双方の蓄積機構を解析し、種々の重要な知見を得た。それらの中でも、ゲノム編集技術を用いて、種々の卵黄形成関連因子の機能を直接的に解析する基盤を確立し、特にリポタンパク質受容体の1種について、卵黄タンパク質の取り込みにおける機能を脊椎動物で初めて明らかにできた点は、学術的意義が極めて高い。本研究で得られた成果は、脂質やタンパク質の卵内への蓄積を人為的に制御できる技術の開発に繋がるものであり、これまでにない画期的な卵質改善法の開発を可能とする点で、その社会的意義も大きい。