甘蓝型油菜热激蛋白HSP70基因家族的鉴定和分析

热休克蛋白也称热激蛋白(heat shock protein, HSP),是植物在受到生长环境中不利的生长因子胁迫时产生的一种用于抗逆的防御蛋白,其中在生物体中分布最普遍的一种热激蛋白是热休克蛋白70 (heat shock protein 70, HSP70)。为全面、深入地了解芸薹属HSP70基因家族的信息,本研究对芸薹属的3个物种(白菜,甘蓝和甘蓝型油菜)进行了生物信息学分析,首先在BRAD数据库中对芸薹属的3个物种进行HSP70基因数目的鉴定,分别在白菜和甘蓝中鉴定出了2个HSP70,在甘蓝型油菜中鉴定出了4个HSP70。将鉴定出来的这8个HSP70基因进行生物信息学分析(系统发生关系,基因结构,保守基序,染色体定位和同源性等),结果显示,芸薹属HSP70基因结构相似,在核酸和蛋白水平均具有高度保守性,进化过程中基本种之间以及天然杂交种与基本种之间均保持着极高的同源性,进化树以及其他生物信息学分析结果还表明甘蓝型油菜的HSP70位点与白菜、甘蓝的HSP70位点符合"禹氏三角"理论,但是根据3个物种的HSP70基因数量及对应关系等分析结果可推测白菜、甘蓝、甘蓝型油菜3个物种的HSP70位点与三倍化理论不完全一致,此结果可反映芸薹属的这3个物种在进化过程中其HSP70基因在数量或结构上发生过变化,致使其不满足三倍化学说。

Identification and Analysis of the Heat Shock Protein HSP70 Gene Family in Brassica napus

Heat Shock Protein(HSP)is a kind of defense protein for stress resistance produced by plants when they are suffering from adverse growth factors in the growing environment.Heat Shock Protein 70(HSP70)is the most widely distributed Heat Shock Protein in organisms among HSP family.In order to comprehensively and deeply understand the information of Brassica HSP70 gene family,bioinformatics analysis of three species in Brassica(Brassica rapa,Brassica oleracea and Brassica napus)has been conducted in this study.First,the number of HSP70 genes in Brassica was identified in the BRAD database.Two HSP70 genes were identified in Brassica rapa and Brassica oleracea respectively,and four HSP70 genes were identified in Brassica napus.The eight HSP70 genes identified in the previous step were analyzed by bioinformatics(Phylogenetic relationship,gene structure,conserved motifs,chromosomal localization,homology,etc.).The results showed that Brassica HSP70 gene was similar in structure and highly conserved in nucleic acid and protein levels.In the process of evolution,the homology in the basic species and between the natural hybrids and the basic species is very high.Phylogenetic tree and other bioinformatics analysis results also showed that the HSP70 site in Brassica rapa,Brassica oleracea and Brassica napus are consistent with the U’s triangle.However,according to the number of HSP70 and the corresponding relationship in the three species in Brassica,an analysis result can be inferred that the HSP70 site of Brassica rapa,Brassica oleracea and Brassica napus are not completely conform to the triploid theory.This result can reflect that the HSP70 gene of these three species of brassica has changed in number or structure during the evolutionary process,which makes it not consistent with triploid theory.