Diversity and evolution of eukaryotic pinocytosis

2019 Fiscal Year Final Research Report

• Project/Area Number: 17K19434
• Research Category: Grant-in-Aid for Challenging Research (Exploratory)
• Allocation Type: Multi-year Fund
• Research Field: Ecology and Evolution (including anthropology), and related fields
• Research Institution: Japan Agency for Marine-Earth Science and Technology
• Principal Investigator: YABUKI Akinori 国立研究開発法人海洋研究開発機構, 地球環境部門(海洋生物環境影響研究センター), 研究員 (20711104)
• Co-Investigator(Kenkyū-buntansha): 石田 健一郎 筑波大学, 生命環境系, 教授 (30282198)
• Project Period (FY): 2017-06-30 – 2020-03-31
• Keywords: 真核微生物 / 飲作用 / 吸収栄養 / 微細構造 / 多様性

Outline of Final Research Achievements

The diversity and evolution of pinocytosis that is a biological function to absorb the nutrients via small vesicle formation from outside have been studied focusing microbial eukaryotes. Although little was known about the diversity of microbial eukaryotes that can survive relying on pinocytosis only, we showed that it is common in various eukaryotic lineages, especially in Cercozoa and Diplonemea. On the other hand, the process and places of the vesicle formation in the cells and the dependence on pinocytosis for the growth are different even between closely related species. Our achievements totally contributed to estimate the ancestral state of nutrient acquisition of the eukaryotes and its diversification process: the pinocytosis itself has been equipped at the very early stage of eukaryotic evolution (at the emergence of eukaryotic cell, probably) and the places of the small vesicle formation has been diversified lineages by lineages.

Free Research Field

微生物学

Academic Significance and Societal Importance of the Research Achievements

本課題によってもたらされた知見は、未だ謎が多い真核細胞の成立とその初期進化過程を理解する上で極めて重要な意味を持つ。また多くの系統で浸透栄養に依存した原生生物が認識された事実は、水圏生態系の構造やエネルギーの流れをより正確に理解する上でも重要かつ新たな意味を持つ。飲作用における小胞形成過程に共通性及び系統ごとの特殊性が確認されたことは、真核細胞機能の多様性とその進化の複雑性を示している。そこからは真核生物初期進化をより詳細に理解するための発展的基礎研究の道が拓けただけでなく、細胞機能に着目した生理医学的研究の基盤情報としての価値も期待される。