2022 Fiscal Year Final Research Report

An all-round peroxidase, CWPO-C, regulates plant growth through the auxin catabolism

Research Project

PDF

Project/Area Number	20H03046
Research Category	Grant-in-Aid for Scientific Research (B)
Allocation Type	Single-year Grants
Section	一般
Review Section	Basic Section 40020:Wood science-related
Research Institution	Kyushu University
Principal Investigator	Tsutsumi Yuji 九州大学, 農学研究院, 教授 (30236921)
Co-Investigator(Kenkyū-buntansha)	雉子谷佳男宮崎大学, 農学部, 教授 (10295199) 藤田弘毅九州大学, 農学研究院, 助教 (90264100)
Project Period (FY)	2020-04-01 – 2023-03-31
Keywords	ペルオキシダーゼ / CWPO-C / 成長制御 / 木化制御 / 木部細胞分化 / 重力応答屈性 / オーキシン / 異化反応
Outline of Final Research Achievements	An all-round peroxidase, CWPO-C, has an unique oxidation ability. Compared with wild-type, transgenic Arabidopsis overexpressing CWPO-C (OE) showed shorter stems. Also, The time needed for OE plants standing up from horizontally to vertical was almost double of wild-type during the gravitropic response. Moreover, IAA content was significantly lower in the OE plants than in the wild-type. These results strongly suggest that CWPO-C has pleiotropic effects on plant growth and IAA accumulation. Unlike Arabidopsis OE, the transgenic poplars with over-expression of CWPO-C (OE) did not show remarkable differences of plant growth, gravitropism bending time, and lignin content. On the other hand, transgenic poplars with CWPO-C suppression, showed the reduced lignin content approximately 45% and the increased β-O-4 linkages. These results strongly suggest that CWPO-C plays a role in differentiation and early growth, as well as in lignin polymerization.
Free Research Field	木質化学
Academic Significance and Societal Importance of the Research Achievements	本研究で対象とするCWPO-Cは様々な基質を酸化可能という、ユニークな万能ペルオキシダーゼである。CWPO-Cは成長旺盛な部位に多く発現し、成長ホルモンであるIAAを代謝不活化することにより、植物の成長に対して負の制御を行うこと、ならびに木部細胞分化とリグニン形成に重要な役割を果たしていることが示された。植物に多数のペルオキシダーゼ遺伝子が存在しそれらの個々の機能は不明であったが、今回特定のペルオキシダーゼが成長および木化の制御を行う事は、ペルオキシダーゼの生理機能同定に関する新規な発見である。また、植物の成長をコントロールするツールとしてのペルオキシダーゼ遺伝子制御も期待される。