Cioning And Functional Analysis Of Heat Shock Transcriptional Factor GhHsfAl Gene In Cotton (Gossypium Hirsutum)

Under high heat stress, plant will have heat shock response (HSR), which can induce plants to produceheat shock proteins (HSP). Heat shock proteins acts as molecular chaperones which assists denaturedprotein’s degradation and transportation thus protecting the stability of the intracellular environment andimproving heat resistance of cell. The heat shock protein gene is expressed by heat shock transcriptionfactor (Hsfs) in addition with the gene element of heat shock protein thus promoting heat shock proteingene expressiness.In this study, it is the first time to clone cotton heat shock transcription factor genes HsfA1from cotton.We successfully constructed the vector of plant expression and accessed to the genetically modifiedmaterial which enhances heat resistance, the main results are as follows:1. The cloning of cotton heat shock transcription factor with RACE (rapid-amplification of cDNA ends)technique, using its gene fragment’s3’ end sequence as a probe. Doing BLAST searches in the ESTdatabase of cotton. Analyzing the EST sequences which has more than95%homology as the probe, anduse DNAMAN software to splice to obtain the cotton HsfA1gene (GhHsfA1). The open reading frame ofGhHsfA1gene is1515bp, encoding504amino acids.2. The bioinformatics analysis of cotton GhHsfA1gene showed the amino acid sequence of GhHsfA1gene encoding with its molecular weight of55513.7Da, and theoretical isoelectric point5.45. It hasinherent amino acids conserved domain of the heat shock transcription factor family, and it has highhomology with the major higher plant HsfA1. signal peptide and transmembrane region wasn’t predicted inthe amino acid sequence of GhHsfA1.3. Construct the plant expression vector pCAMBIA-GhHsfA1, agrobacterium mediated transformationof tobacco leaf discs, and screened positive plants. Do high temperature stress test for transgenic plants, andstudied the heat resistance and hereditary of the T1generation. The results showes, T0generatoin performedhigher heat resistance while the heat resistance of the most of T1plants is higher than non transgenic plants.