RGF1 INSENSITIVE 1 to 5, a group of LRR receptor-like kinases, are essential for the perception of root meristem growth factor I in Arabidopsis thaliana  

作　　者：Yang Ou Xiaoting Lu Quaner Zi Qingqing Xun Jingjie Zhang Yujun Wu Hongyong Shi Zhuoyun Wei Baolin Zhao Xiaoyue Zhang Kai He Xiaoping Gou Chuanyou Li Jia Li 

机构地区：[1]Ministry of Education Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou 730000, China [2]State Key Laboratory of Plant Genomics, National Centre for Plant Gene Research, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China

出　　处：《Cell Research》2016年第6期686-698,共13页细胞研究（英文版）

基　　金：Acknowledgments We are grateful to the Arabidopsis Biological Resource Center for the T-DNA insertion lines used in these studies. We also thank Wendy Chen for reading and commenting on the manuscript and Zeping Cai for providing transgenic plant seeds carrying pSHR：：N- LS-YFP, pSCR： ：NLS-YFP, or pWOXS： ：NLS- YFP. This study was supported by the National Natural Science Foundation of China （31470380, 31530005, and 91317311 to JL）.

摘　　要：RGF1, a secreted peptide hormone, plays key roles in root meristem development in Arabidopsis. Previous studies indicated that a functional RGF1 needs to be sulfated at a tyrosine residue by a tyrosylprotein sulfotransferase and that RGF1 regulates the root meristem activity mainly via two downstream transcription factors, PLETHORA 1 （PLT1） and PLT2. How extracellular RGF1 is perceived by a plant cell, however, is unclear. Using genetic approach- es, we discovered a clade of leueine-rich repeat receptor-like kinases, designated as RGF1 INSENSITIVE 1 （RGI1） to RGI5, serving as receptors of RGF1. Two independent rgil rgi2 rgi3 rgi4 rgi5 quintuple mutants display a consistent short primary root phenotype with a small size of meristem. An rgil rgi2 rgi3 rgi4 quadruple mutant shows a sig- nificantly reduced sensitivity to RGF1, and the quintuple mutant is completely insensitive to RGF1. The expression of PLT1 and PLT2 is almost undetectable in the quintuple mutant. Ectopic expression of PLT2 driven by an RGI2 promoter in the quintuple mutant greatly rescued its root meristem defects. One of the RGIs, RGI1, was subsequent- ly analy^ed biochemically in detail. In vitro dot blotting and pull-down analyses indicated that RGI1 can physically interact with RGF1. Exogenous application of RGF1 can quickly and simultaneously induce the phosphorylation and ubiquitination of RGI1, indicating that RGI1 can perceive and transduce the RGF1 peptide signal. Yet, the activated RGI1 is likely turned over rapidly. These results demonstrate that RGIs, acting as the receptors of RGF1, play essential roles in RGF1-PLT-mediated root meristem development in Arabidopsis thaliana.

关 键 词：receptor-like kinase RGF 1 RGF 1 INSENSITIVE PLETHORA ARABIDOPSIS 

分 类 号：Q943[生物学—植物学] S633.4[农业科学—蔬菜学]