Cloning And Expession Analysis Of Stress-Tolerant Related Genes From Agropyron Cristatum (L.) Gaertn

Agropyron cristatum (L.)Gaertn is a perennial grass which grows in arid, semi-arid and alpine regions. Agropyron cristatum (L.)Gaertn is a wild relative of wheat. It represents a strong capacity of cold and drought resistance. It is not only suitable for conservation and afforestation of water and soil in arid areas but for the genetic improvement of wheat because of various favorable genes it has. The intention of this study was to find the antibiotic resistance genes, especially cold-resistance and drought resistance genes in Agropyron cristatum (L.)Gaertn, which would provid a theoretical basis for transgenic research in wheat. By homologous cloning, semi-quantitative RT-PCR and Western blot, some work has been accomplished.1.Using homologous cloning, fragments of 8 different genes were obtained from Agropyron cristatum (L.)Gaertn leaf, four of which were LEA genes (Aclea3,Accor410,Acwzy2,Acwcs120), three were transcription factors(Accbf,Acdreb,Acmyb) and one was house-keeping geneβ-actin (Acβ-actin).2.Semi-quantitative RT-PCR was conducted to study the expression mode of the cloned genes under cold and drought stress. The results showed that Aclea3 and Acwcor410 were sensitive to cold stress, but insensitive to drought; Acwzy2,Acwzy2 and Acmyb were sensitive to drought but not cold; Acwcs120 responded to both cold and drought stress;Accbf was sensitive to cold stress, it also responses to stress,but comparatively insignificant.3.Western blot results showed that there was a dehydrin of 40KD in Agropyron cristatum (L.) Gaertn leaf. The expression of this protein varied as stress degree changed under both cold and drought conditions. The response of this protein to drought was more obvious than to cold stress. It was deduced that this protein was a drought sensitive dehydrin.4.Homology comparison and cluster analysis of Acβ-actin by DNAMAN showed that the protein encoded by Acβ-actin was highly identical with ACTIN in Triticum aestivum. It also supported the view that Agropyron cristatum (L.)Gaertn is a wild relative of wheat in molecular level.