香蕉果皮2个HSP70基因片段克隆及其在热激和冷藏过程中表达.docVIP

香蕉果皮2个HSP70基因片段克隆及其在热激和冷藏过程中表达 　　摘 要: 温度逆境胁迫可以诱导热激蛋白的表达，而热激处理能够减轻果实冷害。为了探讨温度逆境对香蕉热激蛋白基因表达的调控、辨析香蕉热激蛋白基因的表达与果实冷害的关系，采用同源序列法分离了香蕉果皮HSP70基因序列-根据已经报道的HSP70基因的氨基酸保守序列设计引物、以香蕉果皮总 RNA为模板，用RT-PCR方法克隆香蕉的HSP70 cDNA，Northern杂交分析该基因在不同贮藏温度下的表达特征。结果得到2个序列不同的HSP70基因片段，分别命名为Ma-HSP70-1和Ma-HSP70-2，Ma-HSP70-1和Ma-HSP70-2之间的碱基同源性为86.9%，氨基酸同源性为97.1%。Northern杂交的结果表明，38 ℃短期热激处理诱导了Ma-HSP70-2基因的表达，低温冷藏能使2个基因的表达增强。并初步认为Ma-HSP70可能与香蕉果实耐冷性有关。 　　关键词： 香蕉； HSP70； cDNA克隆； 序列分析； Northern杂交 　　中图分类号???Ｓ６６8．1 文献标志码：Ａ 文章编号：１００９－９９８０（２０12）０2－0241－０5 　　 　　Cloning and expression analysis of two fragments of HSP70 cDNA in the peel of banana during storage at high and low temperature 　　HE Li-hong1，2，CHEN Jian-ye2，WANG Hai-lan2，KUANG Jian-fei2，LU Wang-jin2* 　　（1College of Life Science，Zhongkai University of Agriculture and Engineering，Guangzhou，Guangdong 510225 China； 2Guangdong Key Lab for Postharvest Science，College of Horticulture，South China Agricultural University，Guangzhou，Guangdong 510642 China） 　　Abstract: Many evidences have indicated that temperature stress can induce heat shock protein expression and heat treatment can alleviate chilling injury of fruits. In the present study， two HSP70 fragments were cloned from banana peel using homology-based method in order to investigate their expressions regulated by temperature stress and the relationship between their expressions and chilling injury. Using PCR degenerate primers designed with reference to the conserved amino acid sequences of known HSP70， total RNA extracted from banana peel was used as templates and HSP70 cDNA fragments were amplified by RT-PCR in order to study their expression characteristics under different environments by Northern hybridization. Two different cDNA fragments， named Ma-HSP70-1 and Ma-HSP70-2， were cloned. The homology between two HSP70 is 86.9% at nucleotide acid sequence level and 97.1% at amino acid sequence level. Using Ma-HSP70-1 and Ma-HSP70-2 as probes， Northern hybridization showed that short-time heat p