Cloning And Stress-resistance Study Of Heat Shock Transcription Factor ZmHsf01 From Zea Mays

Maize is the largest grass plant in the world,accounting for about half of the world’s food crops.During the process of growth,maize often suffers from many poor environmental stresses,which leads to a decline of maize yield and quality.In recent years,the global average temperature keeps rising and extreme high temperature weather occurs frequently.High temperature has become one of the important environmental factors affecting the normal growth of maize.The results showed that transcription factors play an important role in plant response to high temperature stress.However,functional studies of maize Hsf gene have rarely been reported.Based on the preliminary research in the laboratory,we obtained a potential heat stress related Hsf gene ZmHsf01 through bioinformatics analysis.The main results are as follows:1.The full-length CDS sequence of ZmHsf01 was cloned from maize B73.The gene ZmHsf01 was 1155bp in length and encoded 384 amino acids,with a molecular weight of 43.28kda and an isoelectric point of 5.07.Meanwhile,its evolutionary analysis found that many members of ZmHsf01 and A2 family had a high degree of homology.2.The results of induced expression analysis showed that ZmHsf01 gene could be highly expressed by drought and high temperature,but was down-regulated by ABA and Nacl treatment.The results of subcellular localization showed that ZmHsf01 was expressed in both cell nucleus and cell membrane.Transcriptional activity analysis showed that ZmHsf01 gene had transcriptional activity in yeast AH 109 strain.3.In this study,a transgenic arabidopsis strain with ZmHsf01 gene overexpression was developed.The length of hypocotyl growth and seedling survival rate of both transgenic and wild arabidopsis thaliana seeds after heat shock treatment were calculated respectively.The results showed that the length of hypocotyl elongation and seedling survival rate of ZmHsf01 gene were significantly higher than those of wild arabidopsis thaliana after high temperature treatment.In transgenic arabidopsis thaliana,the expression level of several adversity related genes increased after heat shock treatment and was higher than that of wild-type plants.The above results indicated that ZmHsf01 gene could improve the heat resistance of transgenic arabidopsis thaliana.4.Mu transposon homozygous mutant of ZmHsf01 gene was obtained from MaizeGDB.High temperature phenotype identification showed that the mutant was more sensitive to high temperature than the wild type plant W22.And the content of proline in the mutant leaves after high temperature treatment was significantly lower than that of the wild type.All the above results indicated that ZmHsf01 gene was involved in the regulation of plant heat stress response and could improve the ability of plants to withstand high temperature.