Two soybean bHLH factors regulate response to iron deficiency  

作　　者：Lin Li Wenwen Gao Qi Peng Bin Zhou Qihui Kong Yinghui Ying Huixia Shou 

机构地区：[1]State Key Laboratory of Plant Physiology and Biochemistry, College of Life Sciences, Zhejiang University [2]Institute of Crop Science, Anhui Academy of Agricultural Sciences

出　　处：《Journal of Integrative Plant Biology》2018年第7期608-622,共15页植物学报（英文版）

基　　金：supported by the Ministry of Science and Technology of China (2016YFD0100703);the National Natural Science Foundation of China (31572189, 31771689);the Natural Science Foundation of Zhejiang Province (LZ16C 150001 and LY17C130002);the Ministry of Education (B14027)

摘　　要：Iron is an indispensable micronutrient for plant growth and development. Limited bioavailability of Fe in the soil leads to iron deficiency chlorosis in plants and yield loss. In this study, two soybean basic helix-loop- helix transcription factors, GmbHLH57 and GmbHLH300, were identified in response to Fe-deficiency. Both transcription factors are expressed in roots and nodules, and are induced by Fe deficiency; these patterns were confirmed in transgenic hairy roots expressing constructs of the endogenous promoters fused to a GUS reporter gene. Bimolecular fluorescence complementation, yeast two-hybrid and coimmunoprecipitation （co-IP） assays indicated a physical interaction between GmbHLH57 and GmbHLH300. Studies on transgenic soybeansoverexpressing GmbHLH57 that overexpression of each results in no change of the and GmbHLH300revealed transcription factor, alone, responses to Fe deficiency, whereas overexpression of both transcription factors upregulated the downstream Fe uptake genes and increased the Fe content in these transgenic plants. Compared to wild type, these double overexpression transgenic plants were more tolerant to Fe deficiency. Taken together, our findings establish that GmbHLH57 and GmbHLH300 are important transcription factors involved in Fe homeostasis in soybean.Iron is an indispensable micronutrient for plant growth and development. Limited bioavailability of Fe in the soil leads to iron deficiency chlorosis in plants and yield loss. In this study, two soybean basic helix-loop- helix transcription factors, GmbHLH57 and GmbHLH300, were identified in response to Fe-deficiency. Both transcription factors are expressed in roots and nodules, and are induced by Fe deficiency; these patterns were confirmed in transgenic hairy roots expressing constructs of the endogenous promoters fused to a GUS reporter gene. Bimolecular fluorescence complementation, yeast two-hybrid and coimmunoprecipitation （co-IP） assays indicated a physical interaction between GmbHLH57 and GmbHLH300. Studies on transgenic soybeansoverexpressing GmbHLH57 that overexpression of each results in no change of the and GmbHLH300revealed transcription factor, alone, responses to Fe deficiency, whereas overexpression of both transcription factors upregulated the downstream Fe uptake genes and increased the Fe content in these transgenic plants. Compared to wild type, these double overexpression transgenic plants were more tolerant to Fe deficiency. Taken together, our findings establish that GmbHLH57 and GmbHLH300 are important transcription factors involved in Fe homeostasis in soybean.

关 键 词：Leon V. Kochian University of Saskatchewan CANADA 

分 类 号：S565.1[农业科学—作物学]