The main oxidative inactivation pathway of the plant hormone auxin

被引：157

作者：

Hayashi, Ken-ichiro ^{[1
]}

Arai, Kazushi ^{[1
]}

Aoi, Yuki ^{[2
]}

Tanaka, Yuka ^{[1
]}

Hira, Hayao ^{[3
]}

Guo, Ruipan ^{[4
]}

Hu, Yun ^{[4
]}

Ge, Chennan ^{[4
]}

Zhao, Yunde ^{[4
]}

Kasahara, Hiroyuki ^{[3
,5
]}

Fukui, Kosuke ^{[1
]}

机构：

[1] Okayama Univ Sci, Dept Biochem, Okayama 7000005, Japan

[2] Tokyo Univ Agr & Technol, United Grad Sch Agr Sci, Dept Biol Prod Sci, Fuchu, Tokyo 1838509, Japan

[3] Tokyo Univ Agr & Technol, Grad Sch Agr, Fuchu, Tokyo 1838509, Japan

[4] Univ Calif San Diego, Sect Cell & Dev Biol, Gilman Dr Jolla, San Diego, CA 92093 USA

[5] RIKEN, Ctr Sustainable Resource Sci, Yokohama, Kanagawa 2300045, Japan

来源：

NATURE COMMUNICATIONS | 2021年 / 12卷 / 01期

基金：

日本学术振兴会; 美国国家卫生研究院;

关键词：

CONJUGATE HYDROLASES; PHENYLACETIC ACID; ARABIDOPSIS; FAMILY; BIOSYNTHESIS; HOMEOSTASIS; GENE; GLUCOSYLTRANSFERASE; DIOXYGENASE; EXPRESSION;

D O I：

10.1038/s41467-021-27020-1

中图分类号：

O [数理科学和化学]; P [天文学、地球科学]; Q [生物科学]; N [自然科学总论];

学科分类号：

07 ; 0710 ; 09 ;

摘要：

Inactivation of the phytohormone auxin plays important roles in plant development, and several enzymes have been implicated in auxin inactivation. In this study, we show that the predominant natural auxin, indole-3-acetic acid (IAA), is mainly inactivated via the GH3-ILR1-DAO pathway. IAA is first converted to IAA-amino acid conjugates by GH3 IAA-amidosynthetases. The IAA-amino acid conjugates IAA-aspartate (IAA-Asp) and IAA-glutamate (IAA-Glu) are storage forms of IAA and can be converted back to IAA by ILR1/ILL amidohydrolases. We further show that DAO1 dioxygenase irreversibly oxidizes IAA-Asp and IAA-Glu into 2-oxindole-3-acetic acid-aspartate (oxIAA-Asp) and oxIAA-Glu, which are subsequently hydrolyzed by ILR1 to release inactive oxIAA. This work established a complete pathway for the oxidative inactivation of auxin and defines the roles played by auxin homeostasis in plant development. Auxin inactivation plays important roles in plant development. Here the authors show that the main route of IAA inactivation in Arabidopsis is via conjugation by GH3 IAA-amidosynthetases followed by DAO1 dioxygenase-mediated oxidation of the conjugated forms and hydrolysis by ILR1 to release inactive oxIAA.

引用

页数：11

共 42 条

[1] Auxin methylation is required for differential growth in Arabidopsis [J].