Molecular understanding of symbiosis in coelomic fluids of marine invertebrates: experimental approach for clarifying the symbiotic function.

2023 Fiscal Year Final Research Report

• Project/Area Number: 22K19209
• 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: Nakagawa Satoshi 京都大学, 農学研究科, 准教授 (70435832)
• Project Period (FY): 2022-06-30 – 2024-03-31
• Keywords: 共生

Outline of Final Research Achievements

We have found that unique bacteria, closely related to H. pylori, are consistently present in the coelomic fluids of starfish, Asterias amurensis. In addition, Patiria pectinifera was also found to harbor specific bacteria in their coelomic fluids. This study aimed to uncover the molecular mechanisms and physiological functions of these microbial symbionts using time-series analyses of the microflora and host and microbial gene expression. During FY2022-2023, we primarily conducted transcriptome analyses under various rearing conditions to explore the physiological functions of these bacteria. The low mortality rates in these experiments allowed for extended sample collection, providing valuable data to assess the stability of the symbiosis system. These findings have been presented at scientific conferences and published in international journals.

Free Research Field

微生物生態学

Academic Significance and Societal Importance of the Research Achievements

本研究の意義は、以下の3つの点に集約される。まず、動物の体液に特異微生物が棲息し、動物が新たな生理機能を発揮することを明らかにすることで、生物学の常識に挑戦する。また、人類に蔓延する病原菌の誕生と進化過程を理解することで、医学や農学など幅広い分野に影響を有する。さらに、沿岸生態系の中枢種への新たな対策を創出し、水産業の持続可能性を支援する。本研究は、海洋性無脊椎動物の免疫機能の起源と進化を探りつつ、人類に蔓延する病原微生物の進化の理解や、海洋資源の持続的利用に大きく貢献する微生物学的研究と位置づけられる。