Two VQ Proteins are Substrates of the OsMPKK6-OsMPK4 Cascade in Rice Defense Against Bacterial Blight

Rice

Na Li¹  Xianghua Li¹  Shiping Wang¹  Wenya Xie¹  Juan Li¹  Xiaofeng Qin¹  Yuanrong Kang¹  Zeyu Yang¹  Haigang Ma¹  Qinglu Zhang¹  Jinghua Xiao¹ 

[1] National Key Laboratory of Crop Genetic Improvement, National Center of Plant Gene Research (Wuhan), Huazhong Agricultural University, 430070, Wuhan, China;

关键词: VQ protein;    MAPK;    Bacterial blight;    Phosphorylation;    Oryza sativa;   

DOI  :  10.1186/s12284-021-00483-y

来源: Springer

【 摘 要 】

BackgroundThe plant-specific valine-glutamine (VQ) protein family with the conserved motif FxxxVQxLTG reportedly functions with the mitogen-activated protein kinase (MAPK) in plant immunity. However, the roles of VQ proteins in MAPK-mediated resistance to disease in rice remain largely unknown.ResultsIn this study, two rice VQ proteins OsVQ14 and OsVQ32 were newly identified to function as the signaling components of a MAPK cascade, OsMPKK6-OsMPK4, to regulate rice resistance to Xanthomonas oryzae pv. oryzae (Xoo). Both OsVQ14 and OsVQ32 positively regulated rice resistance to Xoo. In vitro and in vivo studies revealed that OsVQ14 and OsVQ32 physically interacted with and were phosphorylated by OsMPK4. OsMPK4 was highly phosphorylated in transgenic plants overexpressing OsMPKK6, which showed enhanced resistance to Xoo. Meanwhile, phosphorylated OsVQ14 and OsVQ32 were also markedly accumulated in OsMPKK6-overexpressing transgenic plants.ConclusionsWe discovered that OsVQ14 and OsVQ32 functioned as substrates of the OsMPKK6-OsMPK4 cascade to enhance rice resistance to Xoo, thereby defining a more complete signal transduction pathway for induced defenses.

【 授权许可】

CC BY