SERK Family Receptor-like Kinases Function as Co-receptors with PXY for Plant Vascular Development  

作　　者：Heqiao Zhang Xiaoya Lin Zhifu Han Jizong Wang Li-Jia Qu Jijie Chai 

机构地区：[1]Ministry of Education Key Laboratory of Protein Science, Center for Structural Biology, School of Life Sciences, Tsinghua-Peking Joint Center for Life Sciences,Tsinghua University, Beijing 100084, China [2]State Key Laboratory of Protein and Plant Gene Research, School of Life Sciences, Peking-Tsinghua Joint Center for Life Sciences, Peking University,Beijing 100871, China

出　　处：《Molecular Plant》2016年第10期1406-1414,共9页分子植物（英文版）

基　　金：This research was funded by Projects of International Cooperation and Exchanges NSFC （31420103906）, the National Science Foundation of China （31130063 and 31421001） and the Chinese Ministry of Science and Technology （2015CB910200） to J.C and the National Science Foun- dation of China （31370173） to L.Q.ACKNOWLEDGEMENTS We thank Jianhua He at Shanghai Synchrotron Radiation Facility （SSRF） for assistance with X-ray data collection, Dr. Hiroo Fukuda （Tokyo University, Japan） for the pxy-5 single mutant seeds, Dr. Libo Shah （Texas A＆M University） for serk1-1 serk2-1^＋/- bakl-5 mutant seeds, and Dr. Jia Li for other serk mutant seeds, SERK1, SERK2 entry vectors, and pSERKI： SERK1-GFP vector. No conflict of interest declared.

摘　　要：In Arabidopsis, the CLAVATA3/EMBRYO SURROUNDING REGION-RELATED （CLE） peptides play important roles in regulating proliferation and differentiation of plant-specific stem cells. Although receptors of CLEs are reported to be leucine-rich repeat receptor kinases, the mechanisms underlying CLE-induced receptor activation remain largely unknown. Here we show that SOMATIC EMBRYOGENESIS RECEPTOR KINASEs （SERKs） serve as co-receptors in CLE41/TDIF-PXY signaling to regulate plant vascular development. TDIF induces interaction of its receptor PXY with SERKs in vitro and in vivo. Furthermore, the serk1-1 serk2-1 bakl-5 mutant plants are less sensitive to TDIF, phenocopying the pxy mutant with a compromised promotion of procambial cell proliferation. Crystal structure of the PXY-TDIF-SERK2 complex reveals that the last amino acid of TDIF conserved among CLEs and other evolutionary-related peptides is important for the interaction between SERK2 and PXY. Taken together, our current study identifies SERKs as signaling components of the TDIF-PXY pathway and suggests a conserved activation mechanism of CLE receptors.In Arabidopsis, the CLAVATA3/EMBRYO SURROUNDING REGION-RELATED （CLE） peptides play important roles in regulating proliferation and differentiation of plant-specific stem cells. Although receptors of CLEs are reported to be leucine-rich repeat receptor kinases, the mechanisms underlying CLE-induced receptor activation remain largely unknown. Here we show that SOMATIC EMBRYOGENESIS RECEPTOR KINASEs （SERKs） serve as co-receptors in CLE41/TDIF-PXY signaling to regulate plant vascular development. TDIF induces interaction of its receptor PXY with SERKs in vitro and in vivo. Furthermore, the serk1-1 serk2-1 bakl-5 mutant plants are less sensitive to TDIF, phenocopying the pxy mutant with a compromised promotion of procambial cell proliferation. Crystal structure of the PXY-TDIF-SERK2 complex reveals that the last amino acid of TDIF conserved among CLEs and other evolutionary-related peptides is important for the interaction between SERK2 and PXY. Taken together, our current study identifies SERKs as signaling components of the TDIF-PXY pathway and suggests a conserved activation mechanism of CLE receptors.

关 键 词：receptor-like kinase SERK PXY-TDIF vascular development CO-RECEPTOR 

分 类 号：Q94[生物学—植物学]