Identification And Functional Analysis Of Maize Resistance-Related Gene ZmDi19-9(Zea Mays L.)

Maize has become our country's largest food crop,its production and germplasm on the people's production and life are extremely important.However,with the continuous deterioration of global climatic conditions,drought,soil salinization and other disasters seriously restricting the growth and development of corn yield and quality improvement.Plants that grow in the soil are unable to move,and how plants respond to various abiotic stresses in the living environment has become a difficult problem in the current research on plant genetic breeding.Studies have shown that transcription factors can be widely involved in plant responses to stress by regulating gene expression.It is an extremely important molecular switch in stress-resistant signal transduction pathways.The Drought-induced 19(Di19)family is a highly conserved family of transcription factors,and studies in different species have shown that they are closely related to the response to abiotic stress.However,the genetic function of Di19 family in maize has not been reported.Based on this,the bioinformatics method was used to predict the properties of maize Di19 family gene ZmDi19-9.The ZmDi19-9 gene was cloned from maize,and its molecular characteristics and resistance mechanism were studied in this research.The specific results obtained from the experiment are as follows:1.The ZmDi19-9(GRMZM2G014066_T01)gene was screened according to the results of bioinformatics.Sequence analysis showed that the protein encoded by ZmDi19-9contained conserved zf-Di19 and Di19_C domains,and the zf-Di19 domain contained the zinc finger-like 1 and zinc finger-like 2 domains,which are typical transcription factors for the Di19 family.The length of CDS was 744 bp,and the amino acid sequence was 247,containing four intron structures with a molecular weight of 27.1 kD and a theoretical isoelectric point of 5.14.At the 47 th amino acid there is a nuclear output signal,no nuclear localization signal,no signal peptide,no obvious transmembrane domain structure,belonging to the hydrophilic protein.2.The results of qRT-PCR showed that the ZmDi19-9 gene was all expressed in the detected maize tissues,and the highest relative expression was stem and the lowest was root and leaf.The expression pattern of ZmDi19-9 gene was induced by 200 mM NaCl,20% PEG6000 and 100 ?M ABA.3.Subcellular localization experiments showed that ZmDi19-9 protein is located in the nucleus and cell membrane protein.The transcriptional activity assay showed that ZmDi19-9 protein had transcriptional self-activating activity.4.The Arabidopsis thaliana plant overexpressing ZmDi19-9 gene was less inhibited and had better growth status than that of wild type under drought and high salt conditions,and the number of bolting was more.The number of pods is more and the plant height is higher;the Arabidopsis thaliana leaves are larger,the root system is richer,and the tolerance to high salt stress is stronger.5.The germination stage and seedling stage of ZmDi19-9 transgenic Arabidopsis thaliana were not sensitive to ABA.