苦瓜白粉病响应基因McMLO1的克隆及表达分析  

Cloning and Expression Analysis of Powdery Mildew Responsive Gene McMLO1 in Momordica charantia

作　　者：陈龙正[1] 刘静[1] 刘之洋[1] 夏彭飞 袁希汉 宁宇 CHEN Longzheng;LIU Jing;LIU Zhiyang;XIA Pengfei;YUAN Xihan;NING Yu(Institute of Vegetable,Jiangsu Academy of Agricultural Sciences,Jiangsu Key Laboratory for Horticultural Crop Genetic Improvement,Nanjing 210014,China;Nanjing Innovation Vegetable Molecular Breeding Research Institute,Nanjing 211899,China)

机构地区：[1]江苏省农业科学院蔬菜研究所,江苏省高效园艺作物遗传改良重点实验室,江苏南京210014 [2]南京新创蔬菜分子育种研究院有限公司,江苏南京211899

出　　处：《华北农学报》2022年第1期165-171,共7页Acta Agriculturae Boreali-Sinica

基　　金：江苏省自然科学基金项目(BK20200279);国家自然科学基金项目(32102392);江苏省农业科技自主创新资金(CX(21)3027)。

摘　　要：MLO基因作为感病因子在调控寄主植物对白粉病的应答反应中发挥着重要作用。为明确苦瓜McMLO1基因在白粉病胁迫下的基因功能,以苦瓜自交系K24为材料对该基因进行了克隆、生物信息预测及表达分析。结果表明,McMLO1基因全长4019 bp,包含15个外显子,其中CDS序列长为1707 bp,编码568个氨基酸。ProtParam预测显示,McMLO1蛋白的分子质量为65.40 ku,理论等电点为9.36,属不稳定亲水蛋白,主要位于细胞膜上;McMLO1蛋白包含一个由477个氨基酸组成的MLO保守结构域,其二级结构主要由无规则卷曲和α-螺旋组成。氨基酸多重序列比对和系统进化分析表明,McMLO1与黄瓜MLO蛋白的同源性较高。qRT-PCR检测结果发现,McMLO1在叶片中的表达量显著高于根、茎、果实等组织。白粉病接种后,McMLO1基因的表达量显著提高,并在6 h达到峰值,推测该基因参与了苦瓜对白粉病侵染的早期应答反应。MLO gene,acting as susceptibility factor,play an important role in regulating responses of host plants against powdery mildew.To determine the gene function of bitter gourd McMLO1 gene,cloning,bioinformatics and expression analysis were carried out in the present study.The results suggested that the full-length of McMLO1 was 4019 bp,among which the CDS sequence was 1707 bp,encoding 568 amino acids.ProtParam prediction indicated McMLO1,whose molecular weight and theoretical isoelectric point was 65.40 ku and 9.36,respectively,was an unstable hydrophilic protein which located in cell membrane.McMLO1 protein,harboring a conserved MLO domain of 477 amino acids,was consisted of random coil and alpha helix on secondary structure.Multiple sequence alignment and phylogenetic analysis revealed high homology between McMLO1 and cucumber MLO protein.qRT-PCR analysis suggested that the expression level of McMLO1 in leaf was much higher than that in other tissues.Moreover,the expression level of McMLO1 was significantly up-regulated and reached peak at 6 hours after inoculation with powdery mildew pathogen,indicating McMLO1 participate in the process in response to powdery mildew in bitter gourd.

关 键 词：苦瓜 白粉病 McMLO1 基因克隆 表达分析 

分 类 号：S642.5[农业科学—蔬菜学] Q78[农业科学—园艺学]