Functional Analysis Of NtDnaJ1 In HSPs Gene Family From Tobacco Under Drought Stress

Dna J protein is a member of HSP40 subfamily in the heat shock protein family,the N-terminal of the protein which encoded by Dna J had a J typical conserved domains.As a molecular chaperone,Dna J participate in the metabolism of a variety of organisms,plays an important role in the development and growth of plants,metabolic regulation and abiotic stresses and so on.The research of mechanism of the Dna J in plants had great significance in the breeding of new varieties of environmental stresses plants,meanwhile,also extended the functions of the HSPs family.In this study,the sequence and function analysis of the Nt Dna J1 gene in HSPs had been analyzed preliminary,the mainly research is as follows:1.15 tobacco varieties were selected for the drought resistance in the production,the better drought resistance were screened,such as Longjiang 851,NC89,etc.Take the drought resistance tobacco varieties which had great difference(Longjiang 851 and Jinxing 6007)to made a gene chip,analyzed the differences in expression levels.Through the analysis the gene chip of the Longjiang 851,the Dna J gene which encoded the heat shock protein was selected and named Nt Dna J1.2.The Nt Dna J1 gene was cloned from the Longjiang 851,the gene was 1257 bp,and the N-terminal of the amino acid sequence was a J conserved domains which contains 70 amino acids.3.The specific expression of Nt Dna J1 in different tissues of plants and 15 tobacco varieties which with different drought resistance was analyzed via Real-time PCR.The results showed that,Nt Dna J1 mainly expressed in the leaves and flowers,at the same time,induced by drought,Nt Dna J1 had a higher expression in better drought resistance varieties.4.After Natural drought,PEG and salt stress treatment,compared with the wild-type Arabidopsis,the at Dna J mutant had greater sensitivity to stress conditions,the results initially proved the importance of Dna J gene in drought resistance.5.The plant overdose expression vector of p27-Nt Dna J1 was constructed,the Nt Dna J1 was over expression in the Arabidopsis,and the results showed that,the transgenic lines had better stress resistance than the wild-type Arabidopsis and mutation of at Dna J under stress.The results proved that,the Nt Dna J1 gene had an important function in the aspect of plant drought resistance,however,on the molecular and protein levels also need more research to reveal the mechanism of action,and then provides the theoretical foundation for plant stress research.