Heat Shock Transcription Factor ZmHsf05 Of Maize Improves Drought Tolerance Of Rice Through ABA-dependent Pathway

Heat shock transcription factors(Hsfs)is a type of transcription factor that can respond to environmental stress.It is widely present in cells and can activate the expression of downstream related genes in response to environmental stress.As an important economic crop,maize has important value in agricultural development.At present,because the growth and development of crops are very seriously affected by environmental stress,improving the ability of crops to cope with stress has become a hot spot in the field of agricultural science and technology research.At present,there are few studies on Hsfs of maize.Combining with the previous research foundation,this study selected the ZmHsf05 gene of maize to conduct a preliminary study on its molecular characteristics and functions,aiming to provide genetic resources and theoretical basis for resistance breeding in maize.1)The total length of the ZmHsf05 of maize sequence is 4207 bp,the coding sequence length is 1080 bp,it encodes 359 amino acid residues,the molecular weight is 40.587 k Da,and the isoelectric point is 5.57.Sequence homology alignment indicates that the gene belongs to A2 type of heat shock transcription factor.2)Using fluorescence real-time quantitative RT-q PCR to analyze the expression pattern of the gene,it was found that the gene is expressed in various tissues,but mainly expressed highly in leaves and stems.And ZmHsf05 can be induced with high expression by high temperature,drought,high salt and ABA treatment.3)The subcellular localization was carried out by the transient transformation system of maize protoplasts,and the gene was found to be located in the nucleus.Analysis of the transcriptional activity of this gene by yeast transformation revealed that the gene does not have yeast transcriptional autoactivation activity.4)The ZmHsf05 overexpressing rice line was created.The statistics of the agronomic traits of the transgenic rice showed that the yield of the transgenic rice increased significantly compared with the wild-type rice ZH11,but the grain type of the transgenic rice seeds changed.5)The phenotype analysis of the transgenic rice found that the gene improved the drought tolerance of the transgenic rice.This phenotype was further verified by the change of proline content and the change of leaf water loss rate.At the same time,we found that the gene can improve the salt tolerance of transgenic rice.6)The ABA sensitivity experiment found that the transgenic rice has increased sensitivity to ABA.It is speculated that the ZmHsf05 of maize may improve the drought tolerance of the transgenic rice through the ABA-dependent pathway.7)Through the BIFC experiment,it was found that the corn ZmHsf05 can form multimers with itself,and can interact with the ZmHsf17(Hsf A2)of maize.