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 reporte...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.展开更多
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.
文摘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.
