芹菜NHL-like蛋白基因克隆与表达分析  

Cloning and Expression Pattern Analysis of NHL-like Protein Gene in Celery

作　　者：李岩[1] 王枫[1] 谭国飞[1] 贾晓玲[1] 蒋倩[1] 熊爱生[1] 

机构地区：[1]南京农业大学园艺学院作物遗传与种质创新国家重点实验室/农业部华东地区园艺作物生物学与种质创新重点实验室,南京210095

出　　处：《植物遗传资源学报》2014年第4期788-794,共7页Journal of Plant Genetic Resources

基　　金：国家自然科学基金项目(31272175);教育部新世纪优秀人才支持计划(NCET-11-0670);江苏省杰出青年基金项目(BK20130027);江苏高校优势学科建设项目(2011PAPD);江苏省双创计划(2011JSSC)

摘　　要：植物生长发育过程中会遭遇各种病原物的攻击,植物为了应对这些危害并适应外界的生存竞争,逐渐演化出了复杂的防御机制。NHL基因家族庞大,部分NHL基因受病原物诱导后会过量表达,增强植物对多种病原菌的抗性,是与植物防御机制密切相关的蛋白。本研究以津南实芹和美国西芹2个芹菜品种为试验材料,分别克隆出NHL-like蛋白基因AgNHL。序列分析表明,上述2种芹菜的AgNHL基因序列均含636 bp的开放阅读框,编码211个氨基酸。2种芹菜碱基序列,只有第36位不同,津南实芹为T,美国西芹为C,2种碱基序列相似性高达99.84%,编码的氨基酸序列相同。进化分析显示,2种芹菜的NHL-like蛋白与葡萄、大豆等植物的相似度较高,在第80～185氨基酸间含一个LEA-2蛋白保守结构域。荧光定量PCR结果表明,AgNHL基因主要在芹菜茎中表达,根中表达量最低,有明显组织特异性,品种差异也很显著。对2种芹菜分别进行4℃低温、38℃高温、20%PEG处理、0.2 mol/L NaCl处理2 h表达分析显示,低温、盐处理下该基因表达量明显上升。Plant is frequently exposed to various pathogens environments during its growth and can withstand most attacks by inducing appropriate defense systems. Most of the NHL genes appear to be involved in pathogen-resistance mechanisms in higher plant. The steady-state transcription levels of some NHL genes could be altered when plants are attacked by bacterial pathogens. NHL-like proteins play important roles in the defense systems in higher plants. In this study,bioinformatics approach was utilized for analyzing nucleotide and amino acid sequences of AgNHL gene,which were cloned from celery（ Apium graveolens） cultivars Jinnan Shiqin and and Meiguo Xiqin,respectively.Sequence analysis indicated that the AgNHL gene contained a 636 bp ORF,which encoded 211 amino acid residues.There was only one nucleotide site and no amino acid site difference between the AgNHL genes from the two cultivars.NHL-like protein of celery had a high homology with other higher plants,such as Vitis vinifera and Glycine max. Among the amino acids,80-185 had a conserved domain of LEA-2. Real-time quantitative PCR analysis showed that the AgNHL gene was tissue-specific expressed mainly in the stem,but expression level was low in the root. The expression profiles of the AgNHL gene were also detected by real-time quantitative PCR under 4 ℃,38 ℃,NaCl,and PEG treatments for 2hours in the two celery varieties. The gene expression was significantly induced under low temperature and salt stresses.

关 键 词：芹菜 NHL-like蛋白 基因克隆 荧光定量PCR 表达分析 

分 类 号：S636.3[农业科学—蔬菜学]