Turn on the diatom frustule formation switch and search for proteins associated with frustule formation

2023 Fiscal Year Final Research Report

• Project/Area Number: 21K15131
• Research Category: Grant-in-Aid for Early-Career Scientists
• Allocation Type: Multi-year Fund
• Review Section: Basic Section 44040:Morphology and anatomical structure-related
• Research Institution: Yamagata University
• Principal Investigator: Nomura Mami 山形大学, 理学部, 助教 (40770342)
• Project Period (FY): 2021-04-01 – 2024-03-31
• Keywords: 珪藻 / 有孔虫 / バイオミネラリゼーション / シリカバイオミネラリゼーション / 共生

Outline of Final Research Achievements

Diatoms form elaborate siliceous frustules that are beyond human processing technology, but it is unclear in which proteins are actually involved in the formation of siliceous frustules. In this study, using an innovative system in which symbiotic diatoms living in foraminifera can switch siliceous frustule formation from OFF to ON, the goal was to analyze changes in gene expression over time using single-cell RNA-seq. First, to establish culture strains of foraminifera-symbiotic diatoms, two species of diatom-symbiotic foraminifera were collected in Okinawa and Shizuoka prefectures, and symbiotic diatoms were extracted from the foraminifera cells. Currently, the culture has been successfully grown, although in a crude culture. In the future, species identification and single-cell RNA-seq reference sequences will be obtained.

Free Research Field

細胞生物学

Academic Significance and Societal Importance of the Research Achievements

珪藻は海洋の一次生産の約20％を占める程のバイオマスをもち、珪藻による珪素循環は生態学的に非常に大きな影響を及ぼす。つまり、珪藻におけるシリカバイオミネラリゼーションのメカニズムを明らかにすることは、地球規模の物質循環を理解するうえでも重要であると言える。本研究において、2種の底生性有孔虫から共生珪藻を取り出し、クローンではないものの、培養に成功したことは海の生態系理解において非常に大きな成果である。今後、今回確立された有孔虫共生珪藻培養株のRNA-seqを行い、本珪藻株が新規系統であるのかを含め解析を行うことで、多様性の理解につなげたい。