Structure-based Development of New GA Inhibitor

2018 Fiscal Year Final Research Report

• Project/Area Number: 16H04907
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Single-year Grants
• Section: 一般
• Research Field: Applied biochemistry
• Research Institution: Nagoya University
• Principal Investigator: Ueguchi-Tanaka Miyako (田中美弥子) 名古屋大学, 生物機能開発利用研究センター, 准教授 (70377795)
• Research Collaborator: MIKAMI bunzo
• Project Period (FY): 2016-04-01 – 2019-03-31
• Keywords: ジベレリン / プロヘキサジオン / 阻害剤

Outline of Final Research Achievements

The plant growth regulator, prohexadione (PHX) is widely used in agronomic and horticultural crops to reduce unwanted longitudinal shoot growth without lowering plant productivity by inhibiting gibberellin (GA) biosynthesis enzyme.
We elucidated the co-crystal structure with the substrates GA and PHX using the GA biosynthetic enzyme, GA3-oxidase and the metabolic enzyme, GA2-oxidase, and estimated the amino acids that determine the difference in reactivity of both enzymes towards them. This will provide clues for elucidation of a series of mechanisms from GA biosynthesis to metabolic pathways, and it can be expected that it will lead to the development of novel plant growth regulator specific to both enzymes in the future.

Free Research Field

ゲノム農学

Academic Significance and Societal Importance of the Research Achievements

植物分野ではほとんど行われてこなかったタンパク質のX線結晶構造解析に基づいた構造活性相関（タンパク質化合物間相互作用）研究を行い、初めてGAの生合成及び代謝酵素と基質・植調剤との共結晶構造を明らかにした。これにより、阻害の作用機作ならびに構造と活性相関関係が明らかになりつつあるとともに、新たな植調剤の創生や植物分子育種の方法の開発につながることが予想され、今後の農業の新しい展開において、必ずや有意義な知見を与えるものと考える。