Year: 2020
Type: article
Abstract: Allosteric regulation is protein activation by effector binding at a site other than the active site. Here, we show via X-ray structural analysis of gibberellin 2-oxidase 3 (GA2ox3), and auxin dioxygenase (DAO), that such a mechanism maintains hormonal homeostasis in plants. Both enzymes form multimers by interacting via GA 4 and indole-3-acetic acid (IAA) at their binding interface. Via further functional analyses we reveal that multimerization of these enzymes gradually proceeds with increasing GA 4 and IAA concentrations; multimerized enzymes have higher specific activities than monomer forms, a system that should favour the maintenance of homeostasis for these phytohormones. Molecular dynamic analysis suggests a possible mechanism underlying increased GA2ox3 activity by multimerization—GA 4 in the interface of oligomerized GA2ox3s may be able to enter the active site with a low energy barrier. In summary, homeostatic systems for maintaining GA and IAA levels, based on a common allosteric mechanism, appear to have developed independently.
Source: Nature Communications
Institutions: Bioscience and Biotechnology Center, Nagoya University, Nagoya University, National Institutes for Quantum Science and Technology, Kyoto University, National Agriculture and Food Research Organization, Institute of Agrobiological Sciences, Nagoya University Synchrotron Radiation Research Center
Language: English
Subfield: Plant Science
Domain: Life Sciences
Open Access status: gold
Estimated APC paid: $5,380
OpenAlex ID: W3021637963