‘小金海棠’MxCS4基因克隆、表达分析及功能初探  

Cloning, expression analysis and functional study of MxCS4 gene in Malus xiaojinensis

作　　者：李文慧 张立华 钟继亮 邵帮涛 李迎梅 黄鹏飞 李兴国 韩德果 LI Wenhui;ZHANG Lihua;ZHONG Jiliang;SHAO Bangtao;LI Yingmei;HUANG Pengfei;LI Xingguo;HAN Deguo(School of Horticulture and Landscape Architecture,Northeast Agricultural University,Key Laboratory of Biology and Genetic Improvement of Horticultural Crops(Northeast Region),Ministry of Agriculture and Rural Affairs,Harbin 150030,China)

机构地区：[1]东北农业大学园艺园林学院,农业农村部东北地区园艺作物生物学与种质创制重点实验室,哈尔滨150030

出　　处：《东北农业大学学报》2022年第12期26-34,共9页Journal of Northeast Agricultural University

基　　金：国家自然科学基金项目(32172521);黑龙江省自然科学基金联合引导项目(LH-2022C023);东北农业大学青年才俊项目(18QC05);农业农村部园艺作物种质资源利用重点实验室项目(NYZS202205)。

摘　　要：从苹果属‘小金海棠’(Malus xiaojinensis Cheng et Jiang)中克隆得到一个长度为1 218 bp的柠檬酸合成酶基因,命名为MxCS4,预测该基因可翻译为含405个氨基酸蛋白。MxCS4在叶、根和韧皮部表达量较高,在木质部表达量较低。低铁浓度(4μmol·L^(-1))处理时,MxCS4在根和新叶表达量呈先升后降趋势,在成熟叶表达量呈逐渐下降趋势。高铁胁迫(160μmol·L^(-1))处理时,MxCS4在成熟叶表达量呈先升后降趋势,在根和新叶表达量逐渐下降。ABA和IAA处理时,新叶、成熟叶和根MxCS4表达量均呈先升后降趋势。亚细胞定位研究证实MxCS4蛋白定位在细胞膜上。转基因试验结果显示,超表达MxCS4基因提高转基因拟南芥对铁等金属元素吸收运输能力,进而提高其对低铁和高铁的耐受力。In this study, a citrate synthase gene with a length of 1 218 bp was cloned from Malus xiaojinensis Cheng et Jiang and named MxCS4. It was predicted that this gene could be translated into a protein with 405 amino acids. The expression level of Mx CS4 in leaf, root and phloem was higher, but in xylem was lower. When treated with low iron concentration(4 μmol · L^(-1)), the expression of Mx CS4 in root and new leaf increased first and then decreased, and in mature leaf decreased gradually. When dealt with high iron stress(160 μmol · L^(-1)), the expression of MxCS4 in mature leaf increased first and then decreased, and the expression in root and new leaf decreased gradually. Under the treatments of ABA and IAA, the expression of MxCS4 in new leaf, mature leaf and root all increased first and then decreased. Subcellular localization studies confirmed that the MxCS4 protein was localized on the cell membrane. The results of the transgenic test showed that overexpression of the MxCS4 gene increased the absorption and transport capacity of the transgenic Arabidopsis thaliana to iron and other metal elements, thereby increasing its tolerance to low iron and high iron.

关 键 词：小金海棠 MxCS4 铁胁迫 转基因拟南芥 

分 类 号：Q785[生物学—分子生物学]