2019 Fiscal Year Final Research Report
Foraminiferal elemental composition and calcification process
Project/Area Number |
19K21197
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Project/Area Number (Other) |
18H06074 (2018)
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Research Category |
Grant-in-Aid for Research Activity Start-up
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Allocation Type | Multi-year Fund (2019) Single-year Grants (2018) |
Review Section |
0702:Biology at cellular to organismal levels, and related fields
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Research Institution | Japan Agency for Marine-Earth Science and Technology (2019) National Museum of Nature and Science, Tokyo (2018) |
Principal Investigator |
NAGAI Yukiko 国立研究開発法人海洋研究開発機構, 超先鋭研究開発部門(超先鋭技術開発プログラム), 技術スタッフ (20822612)
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Project Period (FY) |
2018-08-24 – 2020-03-31
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Keywords | 電子顕微鏡 / バイオミネラリゼーション / 有孔虫 / FIB(集束イオンビーム) / カルサイト / 微細構造観察 |
Outline of Final Research Achievements |
Trace element and isotopic compositions of calcareous foraminifers shells have been used as various paleo-environmental proxies, and their chemical/isotopic compositions are known to differ not only from environmental factors but also from species to species. This species-specific compositional variation has been called "vital effect". The cause of vital effect remains unclear, as do the formation process of foraminiferal shells and the uptake of elements with the cellular level. In the present project, we used three species of foraminifera with different Mg content in the shells. Furthermore, shell formation steps and the completeness of the organic membrane covering the site of calcification have been observed with these three species. Besides, the cytoplasmic ultra-structures of the site of calcification show different morphology in each species.
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Free Research Field |
細胞生物学
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Academic Significance and Societal Importance of the Research Achievements |
Mg含有率の異なる有孔虫3種の殻形成過程の観察や殻形成部位の微細構造観察を行ったところ、殻形成に要する時間や殻形成部位への細胞質のアプローチに違いが見えてきた。このことから各々の有孔虫に異なる殻形成戦略があることが示された。地球科学的問題に対し生物学的なアプローチを加えたことで今日まで棚上げにされてきた種特異的な殻組成の変異の要因を知る緒を得た。今後は海水から殻への分配係数を把握することで、これまでの研究の信頼性をより高め、欠落していた環境因子に対する指標の開発にも繋がるだろう。他種での観察を続け、また細胞レベルでの元素の取り込み把握の為に細胞内外の元素の可視化を行う必要があると考えられる。
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