经羧甲基壳聚糖诱导的葡萄柚果实转录组WRKY基因分析及抗性相关基因挖掘  

Carboxymethyl chitosan-induced transcriptome WRKY genes analysis and resistance-related gene mining in grapefruit fruit

作　　者：杨清 刘胜红 黄二宾 杜嵘宇 王芳 邓佳 YANG Qing;LIU Shenghong;HUANG Erbin;DU Rongyu;WANG Fang;DENG Jia(College of Forestry,Southwest Forestry University,Kunming 650224,China;Key Laboratory of National Forestry and Grassland Administration on Biodiversity Conservation in Karst Mountainous Areas of Southwest China,Kunming 650224,China;Key Laboratory of Forest Resources Conservation and Utilization in the Southwest Mountains of China,Ministry of Education,Kunming 650224,China)

机构地区：[1]西南林业大学林学院,云南昆明650224 [2]西南喀斯特山地生物多样性保护国家林业和草原局重点实验室,云南昆明650224 [3]西南山地森林资源保育与利用教育部重点实验室,云南昆明650224

出　　处：《浙江农业学报》2023年第3期598-614,共17页Acta Agriculturae Zhejiangensis

基　　金：国家自然科学基金(31960326,32160394);云南省高层次人才培养支持计划(YNWR-QNBJ-2020-205);云南省两类人才培养项目(202105AC160045);云南省农业联合专项(202101BD070001-065)。

摘　　要：本实验以采后葡萄柚果实为材料,使用1.5%的羧甲基壳聚糖(CMCS)溶液和无菌水浸泡诱导24 h后,研究其对指状青霉(Penicillium digitatum)和扩展青霉(Penicillium expansum)引起的绿霉病的抗病效果,结果表明,CMCS处理组可显著降低P.digitatum和P.expansum引起的绿霉病发病率且病斑直径增长速度受到抑制。以此为基础,对上述CMCS和无菌水处理的葡萄柚果皮进行无参转录组测序,筛选CMCS诱导下的差异表达基因(DEGs)。结果表明,从经CMCS处理的葡萄柚果皮共获得85个差异表达基因,其中上调基因67个,下调基因18个,对差异表达的基因进行GO及KEGG分析。这些差异表达基因的功能归类于生物过程、细胞组分及分子功能3大类37个GO条目,并显著富集在20条KEGG代谢通路中。同时,对参与其中的WRKY基因进行了挖掘,筛选出最有可能参与植物抗病过程的5个WRKY基因均为上调表达,与拟南芥的进化树分析表明,筛选出的5个WRKY基因与拟南芥基因功能类似。涉及的DEGs功能主要与次生代谢、植物激素信号转导、过氧化物酶体、内质网中的蛋白质加工、谷胱甘肽代谢、苯丙烷生物合成等途径有关,8个关键差异表达基因qRT-PCR验证结果表明,调控趋势与转录组学趋势一致。本研究结果可为CMCS诱导葡萄柚抗性相关基因的挖掘和葡萄柚采后分子抗性机制的研究提供理论依据。In this experiment,postharvest grapefruit fruits were treated with a 1.5%carboxymethyl chitosan(CMCS)solution and sterile water for 24 hours to study their resistance to green mould caused by Penicillium digitatum and Penicillium expansum.Results showed that the CMCS treatment group significantly reduced the incidence of green mould caused by P.digitatum and P.expansum and inhibited the growth rate of spot diameter.Non-reference transcriptome sequencing was conducted on CMCS and sterile water-treated grapefruit peels to screen for CMCS-induced differentially expressed genes(DEGs).A total of 85 DEGs were obtained,including 67 up-regulated genes and 18 down-regulated genes.GO and KEGG analyses were performed on the DEGs,and their functions were categorized into 37 GO entries in three major categories:biological processes,cellular components,and molecular functions.These DEGs were significantly enriched in 20 KEGG metabolic pathways.Furthermore,WRKY genes were mined,and five WRKY genes were screened as the most likely to be involved in the plant disease resistance process.All five WRKY genes were up-regulated,and the evolutionary tree analysis with Arabidopsis showed that the five WRKY genes were functionally similar to those of Arabidopsis genes.The functions of the involved DEGs were mainly related to secondary metabolism,phytohormone signaling,peroxisome,protein processing in the endoplasmic reticulum,glutathione metabolism,and phenylpropane biosynthesis pathways.qRT-PCR validation of the eight key differentially expressed genes showed that the regulatory trends were consistent with transcriptomic trends.These results may provide a theoretical basis for mining CMCS-induced resistance-related genes in grapefruit and studying postharvest molecular resistance mechanisms in grapefruit.

关 键 词：羧甲基壳聚糖 无参转录组测序 生物信息分析 诱导抗性 

分 类 号：Q943.2[生物学—植物学]