6AVH

GH3.15 acyl acid amido synthetase

6AVH の概要

• エントリーDOI: 10.2210/pdb6avh/pdb
• 分子名称: GH3.15 acyl acid amido synthetase, ADENOSINE MONOPHOSPHATE (2 entities in total)
• 機能のキーワード: auxin, plant hormone, amino acid, ligase, plant protein
• 由来する生物種: Arabidopsis thaliana (Mouse-ear cress)
• タンパク質・核酸の鎖数: 4
• 化学式量合計: 269598.73

構造登録者

Sherp, A.M.,Jez, J.M. (登録日: 2017-09-02, 公開日: 2018-02-14, 最終更新日: 2024-10-23)

主引用文献

Sherp, A.M.,Westfall, C.S.,Alvarez, S.,Jez, J.M.
Arabidopsis thalianaGH3.15 acyl acid amido synthetase has a highly specific substrate preference for the auxin precursor indole-3-butyric acid.
J. Biol. Chem., 293:4277-4288, 2018

PubMed Abstract: Various phytohormones control plant growth and development and mediate biotic and abiotic stress responses. Gretchen Hagen 3 (GH3) acyl acid amido synthetases are plant enzymes that typically conjugate amino acids to indole-3-acetic acid (IAA) or jasmonic acid (JA) to inactivate or activate these phytohormones, respectively; however, the physiological and biological roles of many of these enzymes remain unclear. Using a biochemical approach, we found that the GH3.15 (AtGH3.15) preferentially uses indole-3-butyric acid (IBA) and glutamine as substrates. The X-ray crystal structure of the AtGH3.15·AMP complex, modeling of IBA in the active site, and biochemical analysis of site-directed mutants provide insight on active site features that lead to AtGH3.15's preference for IBA. Assay-based analysis of AtGH3.15-overexpressing lines indicated that their root elongation and lateral root density were resistant to IBA treatment but not to treatment with either IAA or JA. These findings suggest that AtGH3.15 may play a role in auxin homeostasis by modulating the levels of IBA for peroxisomal conversion to IAA. Analysis of promoter-driven yellow fluorescent protein reporter lines revealed that is expressed at significant levels in seedlings, roots, and parts of the siliques. We conclude that AtGH3.15 is unique in the GH3 protein family for its role in modifying IBA in auxin homeostasis and that it is the first GH3 protein shown to primarily modify a plant growth regulator other than IAA and JA.

PubMed: 29462792
DOI: 10.1074/jbc.RA118.002006

実験手法

X-RAY DIFFRACTION (3.011 Å)