Low phosphorus promotes NSP1–NSP2 heterodimerization to enhance strigolactone biosynthesis and regulate shoot and root architecture in rice  

作　　者：Kun Yuan Hao Zhang Chaoji Yu Nan Luo Jijun Yan Shuang Zheng Qingliang Hu Dahan Zhang Liquan Kou Xiangbing Meng Yanhui Jing Mingjiang Chen Xinwei Ban Zongyun Yan Zefu Lu Jian Wu Yu Zhao Yan Liang Yonghong Wang Guosheng Xiong Jinfang Chu Ertao Wang Jiayang Li Bing Wang 

机构地区：[1]State Key Laboratory of Plant Genomics and National Center for Plant Gene Research(Beijing),Institute of Genetics and Developmental Biology,Innovation Academy for Seed Design,Chinese Academy of Sciences,Beijing 100101,China [2]University of Chinese Academy of Sciences,Beijing 100049,China [3]National Key Laboratory of Plant Molecular Genetics,CAS Center for Excellence in Molecular Plant Sciences,Institute of Plant Physiology and Ecology,SIBS,Chinese Academy of Sciences,Shanghai 200032,China [4]State Key Laboratory of Crop Gene Resources and Breeding,Institute of Crop Sciences,Chinese Academy of Agricultural Sciences,Beijing 100081,China [5]Guangdong Laboratory for Lingnan Modern Agriculture,State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources,College of Agriculture,South China Agricultural University,Guangzhou 510642,China [6]National Key Laboratory of Crop Genetic Improvement,Hubei Hongshan Laboratory,Huazhong Agricultural University,Wuhan 430070,China [7]College of Life Sciences,Shandong Agriculture University,Tai’an,Shandong 271018,China [8]Academy for Advanced Interdisciplinary Studies,Nanjing Agricultural University,Nanjing 210095,China [9]Yazhouwan National Laboratory,Sanya,Hainan 572024,China

出　　处：《Molecular Plant》2023年第11期1811-1831,共21页分子植物（英文版）

基　　金：was supported by grants from the Strategic Priority Research Program of the Chinese Academy of Sciences(XDA28030202);the National Key Research and Development of China(2022YFF1002901);the National Natural Science Foundation of China(32122012,32270327);the Youth Innovation Promotion Association of the Chinese Academy of Sciences(2019099).

摘　　要：Phosphorus is an essential macronutrient for plant development and metabolism,and plants have evolved ingenious mechanisms to overcome phosphate(Pi)starvation.However,the molecular mechanisms underlying the regulation of shoot and root architecture by low phosphorus conditions and the coordinated utilization of Pi and nitrogen remain largely unclear.Here,we show that Nodulation Signaling Pathway 1(NSP1)and NSP2 regulate rice tiller number by promoting the biosynthesis of strigolactones(SLs),a class of phytohormones with fundamental effects on plant architecture and environmental responses.We found that NSP1 and NSP2 are induced by Oryza sativa PHOSPHATE STARVATION RESPONSE2(OsPHR2)in response to low-Pi stress and form a complex to directly bind the promoters of SL biosynthesis genes,thus markedly increasing SL biosynthesis in rice.Interestingly,the NSP1/2–SL signaling module represses the expression of CROWN ROOTLESS 1(CRL1),a newly identified early SL-responsive gene in roots,to restrain lateral root density under Pi deficiency.We also demonstrated that GR24^(4DO) treatment under normal conditions inhibits the expression of OsNRTs and OsAMTs to suppress nitrogen absorption but enhances the expression of OsPTs to promote Pi absorption,thus facilitating the balance between nitrogen and phosphorus uptake in rice.Importantly,we found that NSP1p:NSP1 and NSP2p:NSP2 transgenic plants show improved agronomic traits and grain yield under low-and medium-phosphorus conditions.Taken together,these results revealed a novel regulatory mechanism of SL biosynthesis and signaling in response to Pi starvation,providing genetic resources for improving plant architecture and nutrient-use efficiency in low-Pi environments.

关 键 词：RICE Pi deficiency STRIGOLACTONE NSP1 and NSP2 CRL1 nitrogen and Pi absorption 

分 类 号：S511[农业科学—作物学]