Stress-related Functional Analysis Of ZmC3H54 CCCH-type Zinc Finger Protein Gene In Maize (Zea Mays L.)

Maize is not only the staple food crop,but also an important source for feed.Abiotic stresses,especially drought and salt stress are important factors limiting maize productivity.Under stress conditions,expression of a variety of down stream target genes is induced by direct or indirect way to enhance plant resistance to stresses.CCCH type zinc finger protein is a kind of important transcription factor family,but many reports about the stress resistance of CCCH type zinc-finger proteins are on Arabidopsis and rice,less on maize.The thesis is based on evolutionary relationship analysis,a target gene?ZmC3H54?which was expressed by drought and ABA was screened ? According the study of protein sequence and protein activity and expression analysis,exploring it,s stress signal pathways and molecular mechanism.the main results are as follows:1.The results of Real-time PCR showed that ZmC3H54 was induced by exogenous ABA,PEG and high salt stress.Tissue expression pattern analysis shows that ZmC3H54 was expressed in roots,stems,young leaves,tassel filaments,ear,embryo and endosperm,However,the higher relative of expression level was in root and young leaf.2.ZmC3H54 was cloned from Maize B73.The entire coding region of ZmC3H54 is 1119 bp and encodes a polypeptide of 372 amino acids.Suggesting its relative molecular mass is 40.03 kD,and isoelectric point is 8.65.Amino acid sequence analysis showed that ZmC3H54 had two typical CCCH type zinc finger structure?CX₈CX₅CX₃H,CX₅CX₄CX₃H?.3.The results of transcriptional activity analysis showed that Compared with negative control group,yeast cells which are transformed pGBKT7-ZmC3H54 carrier can grow in SD/-Trp-His-Ade /X-?-GAL three short of tablet and show the alpha galactose glucoside enzyme activity,indicate ZmC3H54 could transcribe in yeast cells,by further fragment missing experiment showed that the active region is main in160-195 aa.4.Excessive express ZmC3H54 transgenic plants was no significant difference on the phenotype with the control group.Compared with the control group,after drought stress treatment to restore water,The transgenic plants showed higher survival rate,drought resistance was improved.At the same time,the ABA sensitivity analysis results show that the transgenic rice plants of excessive expression ZmC3H54 showed have more sensitive to ABA.5.ZmC3H54 gene was also overexpressed in arabidopsis thaliana,The ABA sensitivity experimental results show that seed germination and seedling growth of the transgenic arabidopsis were inhibited by ABA,this is consistent with the results in transgenic rice.It is suggested that ZmC3H54 gene may be involved in the ABA signaling pathways,improve the tolerance of plants to drought stress.