Cloning And Expression Of Two Salinity Tolerance Induced Genes TaWRKY79、TaWRKY80from Wheat

Abiotic stresses such as drought, salinity or low temperature are major environmentalfactors that have adverse effects on plant growth and limit crop production. Under stressconditions, plants firstly sense the environmental changes through many ways, and thentransform these changes into the cell signals, finally, transcription factors that accept thesecell signals will act with cis-acting elements and change the expression of stress-responsivegenes, resulting in an enhancement of stress-tolerance in plants. Many genes wereregulated at transcriptional level, and mostly by transcription factors. Therefore,transcription factors play a pivotal role in stress tolerance of plants.In this paper, we describe the cloning and characterization of two genes induced bystress factors from wheat, and designed TaWRKY79、TaWRKY80respectively. The proteinwith328amino acids encoded by TaWRKY79while TaWRKY80protein was composed of458amino acids. Conserved domains analysis shows that both of the two genes belong toThe WRKY Family. Suncellular localization indicated these two proteins are located in thenucleus of onion cells through transient expression experiments. In addition, we cloned andanalyzed the promoter region of TaWRKY79gene,after we obtain the transgenic lines,GUS testing, the results show that the promoter is stress inducible promoter.These two genes were expressed at low levels in wheat seedling leaves and roots, buttheir expression levels were induced by stress factors, such as PEG, high salinity, lowtemperature treatment. These results suggested that they might be involved in abiotic stressresponse.In order to investigate biological functions, overexpression constructs of these twogenes were made and transformed into Arabidopsis by Agrobacterium-mediation. Theseresults indiacted that the transgenic lines overexpressing TaWRKY79improved tolerance todrought, low temperature and high salinity and AAB1、ICE1、ABA2、ABI1gene wasupregulated in the transgenic lines; Transgenic lines overexpressing TaWRKY80improvedtolerance to drought stress and ABI5、SOS1、ABI1、ABI2、ICE1、DRFB、RD19A genewas upregulated in the transgenic lines. These results suggested that TaWRKY79and TaWRKY80gene play important role in stress tolerance. In addition, After Determinationof physiological index,we find that proline value were upregulated in both of the transgeniclinesIn conclusion, these results suggest that TaWRKY79、TaWRKY80may function in thedevelopment and in the signal transduction pathway that involved in abiotic stresses.