摘要
抗坏血酸过氧化物酶(APX)在植物响应逆境胁迫中具有重要作用。根据苎麻转录组测序中的Unigene42508片段序列,通过RT-PCR结合RACE技术从中苎1号苎麻品种中克隆该基因的全长cDNA序列。BLAST分析表明,该基因编码蛋白属于植物过氧化物酶超家族成员,将其命名为BnAPX1。其cDNA全长为1201 bp,含有一个870 bp的开放阅读框,编码一个含289个氨基酸残基,分子量为31.4 kDa,等电点(pI)为5.88的假定蛋白。其氨基酸序列与与棉花(EU244478)、毛白杨(AY789051)、马蹄莲(AF159254)、大豆(AB331961)、豇豆(AY466858)和麻风树(GQ337076)的相似性分别为84%、82%、81%、79%、80%和82%。实时荧光定量PCR检测发现,BnAPX1基因在苎麻根、茎中段、茎尖、茎皮和幼叶各部位均有表达,其中,在苎麻幼叶中表达量最高,且受重金属镉胁迫诱导,显示BnAPX1在植物重金属镉响应中发挥作用。苎麻APX基因序列的获得与表达特性研究为探寻苎麻耐镉分子机理奠定了基础。
Ascorbate peroxidase （APX） is one of the key enzymes of the plant antioxidant system which re- sponds to enviorment stresses. In this study, a novel gene （ BnAPX1 ） was isolated and characterized from Zhongzhu 1 ramie based on the sequence of Unigene42508 fragment by RT-PCR and RACE methods. BnAPX1 consists of 1201 bp nucleotides, contains an ORF of 289 amino acids which encoding a 31.4 kDa protein with a pI value of 5.88. The similarity comparison revealed that the deduced amino acid sequence shared 84% , 82%, 81% , 79% , 80%, and 82% of homology with Gossypium hirsutum （EU244478）, Populus tomentosa （AY789051）, Zantede- schia aethiopica （AF159254）, Glycine max （ AB331961 ）, Vigna unguiculata （ AY466858 ） and Jatropha curcas （GQ337076）. Real-time quantitative PCR was used to analyze expression pattern of BnAPX1 in different organs and under Cd stress. We found that BnAPX1 was mainly expressed in young leaves and highly induced in roots by Cd stress. These results indicated that BnAPX1 might be involved in response to Cd stress. The isolation and ex- pression analysis of BnAPX1 gene could establish the foundation for the future study in the mechanism of Cd stress.
出处
《植物遗传资源学报》
CAS
CSCD
北大核心
2013年第5期879-884,共6页
Journal of Plant Genetic Resources
基金
湖南省科技厅重点项目(2010TP4004-1
2010FJ2013和2012FJ4063)
国家科技支撑计划(2012BAD20B05-04)
湖南省研究生科研创新项目(CX2011B279)
