Elucidation of the mechanism of silica cell wall formation by monitoring the expression dynamics of the cell wall formation-related proteins

2020 Fiscal Year Final Research Report

• Project/Area Number: 18K05818
• 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: Okayama University
• Principal Investigator: Nemoto Michiko 岡山大学, 環境生命科学研究科, 助教 (30625926)
• Project Period (FY): 2018-04-01 – 2021-03-31
• Keywords: 珪藻 / バイオミネラリゼーション / RNA-seq解析

Outline of Final Research Achievements

The purpose of this study is to get insight into the function of silica cell wall formation-related proteins by analyzing the expression pattern of these transcripts during the silica cell wall formation in diatoms. The comprehensive comparative analysis of eight diatom species identified a number of diatom-specific genes that have likely associations with silica cell wall formation, including a previously unrecognized SET domain protein methyltransferase family. Subsequent proteomic analyses revealed the presence of specific silica cell wall-associated proteins in Nitzschia palea. Expression analysis showed that the expression of the diatom-specific SET domain proteins and silica cell wall-associated proteins were upregulated in response to silicon, suggesting that these genes play roles in silica cell wall formation.

Free Research Field

遺伝子工学

Academic Significance and Societal Importance of the Research Achievements

これまで、珪藻の被殻形成関連タンパク質として同定・報告されたタンパク質はジメチル化およびトリメチル化されたリジン残基を持つことが知られており、シリカ形成におけるメチル化修飾の重要性が示唆されていたが、珪藻の被殻形成関連タンパク質をメチル化する酵素は見つかっていなかった。本研究により同定された珪藻特異的新規メチルトランスフェラーゼは、被殻形成関連タンパク質をメチル化することで、珪藻のシリカ形成を制御するタンパク質であることが示唆された。