Molecular Cloning And Functional Studies Of VvCOR27 From Vitis Vinifera

Low temperature in the winter is one of the main factors that affects the development of grape and wine industry in China. Understanding the signal transduction pathway during cold stress will help to breed new cultivars that suitable for the climate condition in China. COR is one of the transcriptional factor which responds to the cold stress in Arabidopsis thaliana, CBF can induce the expression of COR by binding to its DRE/CRT elements, thereby enhancing plant resistance.Based on our previous transcriptome analysis, a gene that showed increased expression pattern in Vitis vinifera L. cv. Muscat Hamburg during cold treatment is identified by molecular cloning and named as VvCOR27. Its function is assessed by gene structure analysis. The main results are that the complete sequence of VvCOR27 is 1,202bp which encode 302 amino acids, the molecular weight of deduced peptide is 33 KD, and the deduced protein is a less stable hydrophilic proteins, but its function is unkonwn. Three COR27-sepcific domains are identified through homology analysis of COR27s from 13 species, in which the highest homology with VvCOR27 is PmCOR27, suggesting that they may have a similar function. The transcript of VvCOR27 was found increased at 24 h and 48 h after cold treatment.4 types of elements, EE, EEL, G-box and ABREL, are found in the regulatory regions (from published Vitis vinifera genome sequences) of VvCOR27, which also exist in AtCOR27 but its numbers twice. This may be one of the reasons that the AtCOR27 show a more quick responsibility to cold treatment than VvCOR27. By predicting the COR27 regulatory pathways in cold conditions, it is found that the expression levels may be affected by abscisic acid (ABA). The mechanism of VvCOR27 transcriptional regulation mechanism can be found through this reasearch.A. thaliana are often used to verify gene functions. In comparison to the wild types, transgenic Arabidopsis over-expressed VvCOR27 shows higher cold tolerance. The results are that the physiological indicators of transgenic Arabidopsis include higher antioxidant enzyme activity and lower membrane lipid peroxidation. The cold-tolerance of the VvCOR27-overexpressed transgenic A. thliana can be significantly enhanced and confirmed that VvCOR27 is a positive regulatory factors in cold-responsive signal transduction pathway. This study can not only promote cold resistance related research, but also provide new ideas and basis for the work of stress tolerance in plants.