Screening And Preliminary Functional Analysis Of Drought Resistant Genes In Caragana Korshinskii Carr

The desert plant Caragana korshinskii grows in a semi-arid and arid area and has strong resistance to stress.This study was based on the differential gene expression database of Caragana korshinskii before and after drought treatment.Through bioinformatics analysis,candidate genes for drought resistance were obtained.Preliminary functional validation analysis was performed on some candidate genes.The main results are as follows:(1)From the 49 differentially up-regulated genes obtained from bioinformatics analysis,14 genes were randomly selected for qRT-PCR detection and found that their expression trends were consistent with the sequencing data.This shows that the difference in drought stress obtained in the previous period is correct for the up-regulated expression of the gene.(2)After further bioinformatics analysis,of the 49 differentially up-regulated genes,only 22 genes had the complete ORF structure;using the designed specific primers for PCR amplification,16 of them were found to be of the correct size.(3)The 16 candidate genes were cloned and the expression vector was constructed.The In-Fusion method was used to link the target gene with the vector,and the recombinant plasmid was constructed and transformed into E.coli.The recombinant plasmid was transferred into Agrobacterium tumefaciens via freeze-thaw method.The positive clones were verified and transformed into Arabidopsis thaliana by the method of Flos solanacea.After the transgenic Arabidopsis seeds were obtained,the root lengths of the transgenic lines of the 16 candidate genes were observed under normal conditions.The results showed that the root lengths of the transgenic lines of the No.9,No.13,and No.18 genes were the same as those of the wild type.longer.Among them,the root length of transgenic line 9 of the gene was significantly higher than that of the wild type.(4)The transgenic strain of No.9 gene was selected for further functional verification of drought stress treatment.The two transgenic lines of No.9 gene were subjected to natural drought treatment and ABA,mannitol,and NaCl simulated drought treatments.It was found that the transgenic offspring of No.9 gene was superior to the wild type in the resistance performance to each stress treatment..The related physiological indexes of the two transgenic lines,including leaf water loss rate,soluble sugar,and chlorophyll content,were tested.The results showed that compared with the wild type,the transgenic plants showed stronger resistance to adverse stress.This indicates that the 9th gene is one of the important drought-resistant genes of Caragana korshinskii.