Cloning And Functional Preliminary Analysis Of HSP Gene In P.cornutum

P.cornutum belongs to the genus Pugionium Gaertn.in the Cruciferae,which is distributed in the desert or grassland sandy land of Gansu,Ningxia,Inner Mongolia,etc.Moreover,it has strong drought and salt tolerance,so it is an ideal material for the research of resistance to stress in plants.Heat shock proteins(HSPs),which are synthesized in response to stress and developmental signals,play an important role in plant resistance to stress.At present,there are few studies on HSP gene in P.cornutum.In this study,Pc HSP17.8,Pc HSP18.1,Pc HSP26.5 and Pc HSP70 were selected by transcriptomic and proteomic analysis in the leaves of P.cornutum.seedlings under drought stress in the early stage,and their clone analysis and functions in stress response were preliminariically studied.The results are as follows:1.The characteristics and phylogenetic relationships of four gene sequences were analyzed.The total length of ORF of the four genes were 471 bp,477bp,699 bp and 1944 bp,respectively,encoding 156,158,232,647 amino acids.2.The expression levels of the four genes were detected by q RT-PCR.The expression levels of Pc HSP were tissue specific and could be induced by drought,Na Cl,low temperature,high temperature and ABA.3.Pc HSP17.8,Pc HSP18.1,Pc HSP26.5 and Pc HSP70 genes were cloned,and p BI121-Pc HSP17.8,p BI121-Pc HSP18.1,p BI121-Pc HSP26.5 and p BI121-Pc HSP70 plant overexpression vectors were constructed.4.Studies on the function of transgenic Arabidopsis Thaliana showed that overexpression of Pc HSP17.8,Pc HSP18.1 and Pc HSP26.5 could improve the tolerance of transgenic Arabidopsis thaliana to Na Cl during seed germination,and overexpression of Pc HSP18.1 could improve the tolerance of transgenic Arabidopsis thaliana to mannitol during seed germination.Compared with the control,the overexpression of Pc HSP17.8,Pc HSP18.1,Pc HSP26.5 and Pc HSP70 increased the heat resistance of transgenic Arabidopsis thaliana at seedling stage,and the overexpression of Pc HSP17.8,Pc HSP18.1and Pc HSP70 increased the drought resistance of transgenic Arabidopsis thaliana at seedling stage.Arabidopsis Thaliana with overexpression of Pc HSP26.5 showed weak response to drought stress.