Overexpression of INCREASED CAMBIAL ACTIVITY, a putative methyltransferase, increases cambial activity and plant growth

作     者：Hyunsook Kim Mikiko Kojima Daeseok Choi Soyoung Park Minami Matsui Hitoshi Sakakibara Ildoo Hwang 

作者机构：Department of Life Sciences Pohang University of Science and Technology Pohang 790-784 Korea Synthetic Genomics Research Team Biomass Research Cooperation Division (BMEP) RIKEN Center for Sustainable Resource Science (CSRS) Tsurumi Yokohama 230-0045 Japan Riken Center for Sustainable Resource Science (CSRS) Tsurumi Yokohama 230-0045 Japan 

出 版 物：《Journal of Integrative Plant Biology》 (植物学报（英文版）)

年 卷 期：2016年第58卷第11期

页      面：874-889页

核心收录：

学科分类：0710[理学-生物学] 09[农学] 0903[农学-农业资源与环境] 0901[农学-作物学] 0703[理学-化学] 0902[农学-园艺学] 

基　　金：the support of “Cooperative Research Program for Agriculture Science & Technology Development (Project No. PJ010953022016)” Rural Development Administration  Korea 

主　　题：Cambial activity cytokinin gibberellin methanol methyltransferase pectin shoot growth 

摘      要：Cambial activity is a prerequisite for secondary growth in plants; however, regulatory factors controlling the activity of the secondary meristem in radial growth remain elusive. Here, we identified INCREASED CAMBIAL ACTIVITY （ICA）, a gene encoding a putative pectin methyltransferase, which could function as a modulator for the meristematic activity of fascicular and interfascicular cambium in Arabidopsis. An overexpressing transgenic line, 35S：＇1CA, showed accelerated stern elongation and radial thickening, resulting in increased accumulation of biomass, and increased levels of cytokinins （CKs） and gibberellins （GAs）. Expression of genes encoding pectin methylesterases involved in pectin modification together with pectin methyltransferases was highly induced in 355：：ICA, which might contribute to an increase of methanol emission as a byproduct in 35S：ICA. Methanol treatment induced the expression of GA- or CK-responsive genes and stimulated plant growth. Overall, we propose that ectopic expression of ICA increases cambial activity by regulating CK and GA homeostasis, and methanol emission, eventually leading to stem elongation and radial growth in the inflorescence stem.