Revealing the molecular mechanism of E3 ubiquitin ligase underlying plant morphological diversity

2022 Fiscal Year Final Research Report

• Project/Area Number: 20K22644
• Research Category: Grant-in-Aid for Research Activity Start-up
• Allocation Type: Multi-year Fund
• Review Section: 0702:Biology at cellular to organismal levels, and related fields
• Research Institution: Tohoku University
• Principal Investigator: Bessho-Uehara Kanako (別所・上原奏子) 東北大学, 生命科学研究科, 助教 (90876624)
• Project Period (FY): 2020-09-11 – 2023-03-31
• Keywords: E3ユビキチンリガーゼ / 相互作用 / 形態形成

Outline of Final Research Achievements

To reveal the regulatory network for plant morphology mediated by the E3 ubiquitin ligase, orthologous genes of rice and Arabidopsis was examined.
I identified RAE3, a gene that regulates the elongation of awn which is spine-like structure at the tip of rice seed, and clarified its subcellular localization and gene expression patterns. In addition to that, by collaborative work, we showed that the different genes were selected during rice domestication in Asia and Africa independently. I also analyzed the Arabidopsis RAE3 ortholog, ATL43. I found that ATL43 overexpression caused loss of serrations and dwarf phenotype. Furthermore, ATL43-TurboID which is the proximity labeling technique made us identify ATL43-interacting proteins, among which CIPK9 was found to interact with ATL43.

Free Research Field

植物生理学

Academic Significance and Societal Importance of the Research Achievements

形態多様性の分子基盤の理解には形態形成の分子機構を解明し、幅広い種で比較を行うことが重要である。種間の遺伝子機能を比較する進化発生生物学的研究はこれまでにも行われてきたが、その多くはホメオティック遺伝子等の転写因子に焦点を当てたもので、遺伝子の発現制御に着目したものであった。しかし一方で、翻訳されたタンパク質の量が形態に与える影響については十分に議論されているとは言えない。申請者は、基質タンパク質にユビキチンを付加し分解させる働きを持つE3ユビキチンリガーゼが異種の植物において異なる器官形態を制御することを見出し、E3ユビキチンリガーゼを基点とした新たな形態形成の分子機構の一端を明らかにした。