西南农业学报2025，Vol.38Issue(9)：1944-1952,9.DOI:10.16213/j.cnki.scjas.2025.9.013
寄生疫霉菌效应因子RxLR750的基因克隆和功能研究
Gene cloning and function analysis of effector RxLR750 from Phytophthora parasitic
摘要
Abstract
[Objective]After infecting plants,Phytophthora pathogens secrete a large number of effectors that target the plant immune system to interfere with normal physiological activities,ultimately leading to disease development.The identification and functional characterization of novel effectors will provide further support for elucidating the pathogenic mechanisms of Phytophthora pathogens.[Method]The study de-signed degenerate primers based on the conserved domain of RxLR effectors and cloned a RxLR effector gene with unknown functions by RT-PCR amplification from the total RNA of tobacco leaves infected by P.parasitic,and this effector gene was named as RxLR750.The sequence homology of RxLR750 with other Phytophthora effectors was analyzed through Blast searching against NCBI database,and the expression level of RxLR750 in tobacco leaves after P.parasitic infection was determined using quantitative RT-PCR.The biological function of RxLR750 in tobacco leaves was studied using Agrobacterium mediated transient expression method.[Result]The amino acid sequence of RxLR750 had a low homology to other Phytophthora effector,and its homology with the effectors of P.sojae,the model strain of Phytophthora,was less than 27.36％.The gene expression level of RxLR750 in tobacco leaves increased in the early stage of P.parasitic infection,but significantly de-creased in the later stage of infection.And,its expression was regulated by jasmonic acid.Transient expression of RxLR750 in tobacco leaves induced leaf necrosis and withered spots,showing a hypersensitivity response.Transcriptional analysis showed that the expression of RxLR750 in tobacco significantly altered the expression of pathogenesis related genes PR1,PR1-1,PR2,PR2-1,PR5,and several key genes functioning in the jasmonic acid pathway such as COI1,JAZ1,MYC2.[Conclusion]RxLR750 is a unique RxLR effector of P.parasitic and exhibits sig-nificant expression changes in tobacco leaves during the infection process.It can cause hypersensitivity reactions of tobacco and is an aviru-lence gene of P.parasitic.The function of RxLR750 in tobacco is related to the jasmonic acid signaling pathway.关键词
寄生疫霉菌/RxLR效应因子/茉莉酸信号途径/致病机理Key words
Tobacco black shank disease/RxLR effector/Jasmonic acid pathway/Pathogenic mechanism分类
农业科技引用本文复制引用
王文静,曹海辉,王嘉豪,阳显斌,黄嘉杰,王寒,曹毅..寄生疫霉菌效应因子RxLR750的基因克隆和功能研究[J].西南农业学报,2025,38(9):1944-1952,9.基金项目
烟草行业病虫害监测与综合治理重点实验室揭榜挂帅项目(KLTPMJMT2022-06) （KLTPMJMT2022-06）
广东中烟工业有限责任公司项目(2024440000340010) （2024440000340010）
中国烟草总公司重大科技项目[110202101055(LS-15)] （LS-15）
山东青岛烟草有限公司科技项目(2023370200240151) （2023370200240151）
