GSK3-mediated stress signaling inhibits legume-rhizobium symbiosis by phosphorylating GmNSP1 in soybean  

作　　者：Chunmei He Hui Gao Haijiao Wang Yun Guo Miao He Yaqi Peng Xuelu Wang 

机构地区：[1]National Key Laboratory of Crop Genetic Improvement,Center of Integrative Biology,College of Life Science and Technology,Huazhong Agricultural University,Wuhan 430070,China [2]State Key Laboratory of Crop Stress Adaptation and Improvement,School of Life Sciences,Henan University,Kaifeng 475001,China

出　　处：《Molecular Plant》2021年第3期488-502,共15页分子植物（英文版）

基　　金：This work was supported by grant 2016YFD0100700 from the National Key Research and Development Program of China(H.W.and B.Z.);grant 0120150092 from the Agricultural Research Outstanding Talents and Innovation Team of Ministry of Agriculture(to X.W.);grant 31870257 from the National Natural Science Foundation of China(to X.W.);grants 2014RC002(to X.W.)and 2662018QD014(to H.W.)from the Fundamental Research Funds for the Central Universities of Huazhong Agricultural University.

摘　　要：Legumes establish symbiotic associations with rhizobia for biological nitrogen fixation.This process is highly regulated by various abiotic stresses,but the underlying genetic and molecular mechanisms remain largely unknown.In this study,we discovered that the glycogen synthase kinase 3(GSK3)-like kinase,GmSK2-8,plays an important role in inhibiting symbiotic signaling and nodule formation in soybean(Glycine max)under salt stress.We found that GmSK2-8 is strongly induced in soybean under high-salt conditions,while GmSK2-8 could interact with two G.max Nodulation Signaling Pathway 1(GmNSP1)proteins,GmNSP1a and GmNSP1b;these key transcription factors are essential for rhizobial infection,nodule initiation,and symbiotic gene expression in soybean.Furthermore,we demonstrated that GmSK2-8 phosphorylates the LHRI domain of GmNSP1a,inhibits its binding to the promoters of symbiotic genes,and thus suppresses nodule formation under salt stress.Knockdown of GmSK2-8 and its close homologs also resulted in reduced plant sensitivity to salt stress during nodule formation.Taken together,our findings indicate that GSK3-like kinases directly regulate the activities of GmNSP1s to mediate salt-inhibited legume–rhizobium symbiosis,providing novel targets for improving symbiotic nitrogen fixation under environmental stress conditions in soybean and possibly other legumes.

关 键 词：nodule formation rhizobial infection salt stress SOYBEAN SYMBIOSIS 

分 类 号：S565.1[农业科学—作物学]