Large-scale screening for factors that disrupt non-membranous organelles in plants

2023 Fiscal Year Final Research Report

• Project/Area Number: 21K19145
• Research Category: Grant-in-Aid for Challenging Research (Exploratory)
• Allocation Type: Multi-year Fund
• Review Section: Medium-sized Section 40:Forestry and forest products science, applied aquatic science, and related fields
• Research Institution: Kyoto University
• Principal Investigator: Yamano Takashi 京都大学, 生命科学研究科, 准教授 (70570167)
• Project Period (FY): 2021-07-09 – 2024-03-31
• Keywords: 非膜オルガネラ / 相分離 / クラミドモナス / ピレノイド

Outline of Final Research Achievements

This study aimed to elucidate the mechanism of disappearance of pyrenoids, non-membranous organelles essential for efficient aquatic photosynthesis. By introducing random mutations into a model green alga Chlamydomonas strain expressing pyrenoid markers and screening approximately 15,000 mutants, we successfully isolated several mutants with abnormalities in pyrenoid number and position. We proceeded to identify the causative genes using next-generation sequencing and established a high-resolution time-lapse observation system for pyrenoid division, which allowed us to quantify the differences in pyrenoid division patterns between wild-type and mutant strains. For some of the mutants, we conducted phenotypic analyses related to photosynthesis, shedding light on the physiological significance of restricting pyrenoid number to one.

Free Research Field

植物分子細胞生物学

Academic Significance and Societal Importance of the Research Achievements

本研究は、水中で効率的な光合成に重要なピレノイドという細胞内器官の消失機構の解明を目指したものである。クラミドモナスでピレノイドに目印を付け、ピレノイドが異常となった変異株を選抜し、その数や位置に異常のある株を複数単離した。原因遺伝子の特定や、高解像度顕微鏡によるピレノイド分裂様式の定量化にも成功した。本研究は、藻類がピレノイドを失った仕組みの理解を深めるとともに、将来的には陸上植物へのピレノイド導入による光合成効率の向上や、食料問題の解決につながる可能性を秘めている。