Defect in an immune regulator gene BrSRFR1 leads to premature leaf senescence in Chinese cabbage

作     者：Xin Y. Song G. Tan C. Feng H. 

作者机构：College of Horticulture Shenyang Agricultural University Liaoning Shenyang 110866 China 

出 版 物：《Horticultural Plant Journal》 (园艺学报（英文版）)

年 卷 期：2024年第10卷第6期

页      面：1414-1423页

核心收录：

学科分类：0710[理学-生物学] 071001[理学-植物学] 07[理学] 

基　　金：National Natural Science Foundation of China, NSFC, (31972405) National Natural Science Foundation of China, NSFC Graduate Student Innovation Cultivation Project of Shenyang Agricultural University, (2021YCXB16) 

主　　题：Chinese cabbage Gene cloning Premature leaf senescence SRFR1 

摘      要：Leaf senescence is the final stage of leaf development, where the nutrients and energy of senescent leaves are redistributed to developing tissues or organs for plant growth, reproduction, and defense. Outer leaves are photosynthetic organs that usually senesce at the late heading stage in Chinese cabbage, and premature leaf senescence often reduces leafy head yield and quality. In this study, 11 premature leaf senescence mutants were screened from an ethyl methanesulfonate-mutagenized population of the double haploid line ‘FT’ in Chinese cabbage. At the early heading stage, the mutants exhibited edge yellowing within its outer leaves, and at the mature stage, its leafy head weight decreased significantly. Genetic analysis revealed that the mutated trait of all 11 mutants corresponds to single gene recessive inheritance. Semi-diallel cross tests showed that 5 of the 11 were allelic mutants. MutMap and Kompetitive Allele Specific PCR genotyping revealed that BraA01g001400.3C was the candidate gene, which is orthologous of Arabidopsis SUPPRESSOR OF rps4-RLD 1, encoding an immune regulator, so we named it as BrSRFR1. All the BrSRFR1 in the five allelic mutants exhibited single nucleotide polymorphisms at different positions on their exons and led to premature translation termination, which confirmed that defect in BrSRFR1 led to premature leaf senescence. These results verify the role of BrSRFR1 on leaf senescence and provide a new insight into the mechanisms of leaf senescence in Chinese cabbage, which reveals a novel function of SRFR1 in plant development. © 2024 Chinese Society for Horticultural Science (CSHS) and Institute of Vegetables and Flowers (IVF), Chinese Academy of Agricultural Sciences (CAAS).