苹果HYL1基因在干旱中的表达与功能分析  

Expression and fuction analysis of MdHYL1 gene in apple under drought tolerance

作　　者：王丽平 姜丽娟 马锋旺[1,2] 管清美 WANG Liping;JIANG Lijuan;MA Fengwang;GUAN Qingmei(College of Horticulture,Northwest A ＆ F University,Yangling,Shaanxi 712100,China;State Key Laboratory of Crop Stress Biology in Arid Areas,Northwest A＆F University,Yangling,Shaanxi 712100,China)

机构地区：[1]西北农林科技大学园艺学院,陕西杨凌712100 [2]旱区作物逆境生物学国家重点实验室,陕西杨凌712100

出　　处：《西北农林科技大学学报（自然科学版）》2018年第7期109-116,共8页Journal of Northwest A&F University(Natural Science Edition)

基　　金：国家自然科学基金项目(31572106;31622049)

摘　　要：【目的】分析干旱处理下苹果HYL1基因(MdHYL1)在苹果中的表达情况,并初步分析过量表达MdHYL1转基因苹果根系的生长情况,以了解MdHYL1在干旱中的功能特性。【方法】从金冠苹果中克隆出MdHYL1基因,对其进行干旱下的表达分析、系统进化分析和组织特异性表达分析;利用Gateway技术构建植物过表达载体pGWB414-MdHYL1,通过根癌农杆菌介导法转化苹果无性系GL-3,经卡那霉素筛选,采用PCR和RTqPCR技术鉴定阳性转基因株系,并对转基因株系的根系生长情况进行观测。【结果】MdHYL1包含长1 479bp的完整开放阅读框,编码492个氨基酸,位于chr15染色体上;系统进化树分析表明,苹果MdHYL1与梅PmHYL1、桃PpHYL1蛋白的关系最近;组织特异性表达分析表明,MdHYL1基因在楸子各组织器官中的表达量为叶>茎>花>根>果实;干旱处理下MdHYL1基因的表达量显著上调,而转基因植株鉴定结果表明,MdHYL1基因已成功转入苹果植株中,3个过表达MdHYL1转基因株系的根系较未转基因株系(对照)明显增多。【结论】MdHYL1基因能够响应干旱胁迫,且转基因苹果根系更发达,表明其可能在苹果耐旱过程中起重要作用。【Objective】The expression level of MdHYL1 and the root growth of MdHYL1 overexpressing transgenic apple under drought treatment were analyzed to understand the function of MdHYL1 gene in drought tolerance of apple.【Method】MdHYL1 gene was cloned from ‘Golden Delicious＇ apple and its expression level under drought,phylogenetic relationship and tissue specific expression were analyzed.The plant overexpression vector pGWB414-MdHYL1 was constructed using the Gateway system.Agrobacterium-mediated transformation was performed using clonal apple GL-3 as the plant vector and positive transgenic lines were selected by kanamycin before being identified by PCR and RT-qPCR.The root growth of transgenic lines was then obeserved.【Result】The MdHYL1 gene contained an ORF of 1 479 bp encoding492 amino acids and was located on chr15.Phylogenetic tree analysis showed that MdHYL1 protein was closely related to PmHYL1 and PpHYL1 proteins.Tissue specific expression showed that the expression level of MdHYL1 gene was in the order of leaf〉stem 〉flower〉root〉fruit.MdHYL1 gene was signifi-cantly up-regulated under drought treatment and three MdHYL1 transgenic lines were identified with remarkably dense roots compared with the untransgenic control.【Conclusion】MdHYL1 gene could respond to drought stress and transgenic apple lines had increased root number,indicating that MdHYL1 gene may play an important role in drought tolerance of apple.

关 键 词：苹果 MdHYL1 转基因 耐旱性 

分 类 号：S661.103.4[农业科学—果树学] Q78[农业科学—园艺学]