The Mechanism Of MYB4 Gene Involved In The Response Of Drought Stress In Plants

Nowadays,drought stress has become a serious problem,which restricted agricultural production in the word.Drought occupies the first place in all abiotic stresses,and it has reduce crop yield by more than 50 percent e very year.Plants grow slowly in mild drought,but severe drought can directly cause plants to death.With the rapid development of molecular biology,genetics,proteomics,transcriptology and other related disciplines,the molecular mechanism of drought resistance in plants have preliminarily revealed.Using transgenic engineering technology to modify and utilize the drought-resistance genes has become a research hotspot in molecular biology.This paper focused on the response mechanism of MYB4 gene in arabidopsis thaliana under drought stress.The results are as follow:?1?qRT-PCR analysis shows that the MYB4gene can be induced under drought stress.?2?The myb4-1mutants were sensitive to drought stress,while the MYB4 over-expression plants were tolerant to drought stress,indicating that MYB4 gene may be involved in the regulation of drought stress.?3?Datas shows that water loss in myb4-1 mutant leaves were faster than wild type?Ler?,and water loss in MYB4 overexpression leaves were slower than wild type?WT?.?4?Furthermore,the stomatal numbers were analyzed.we found that the stomatal numbers of myb4-1 mutant plants were more than the wild type?Ler?plants.It is indicated that the response of MYB4 gene to drought stress may be related to stomatal regulation.?5?The phenotypes suggested that there was no significant difference between myb4-1 mutant and wild type under ABA stress.?6?DAB tissue staining shows that there was no significant difference between myb4-1 mutant and wild type?WT?when treated with exogenous H₂O₂ and drought,indicated that the response of MYB4 gene to drought stress may be independent of the ROS antioxidant pathway.?7?Mannitol assay shows that there was no significant difference in root length and fresh weight between myb4-1 mutant and wild type?Ler?.?8?A ProMYB4:GUS vector was constructed,and then we successfully screened the positive transgenic plants,which provided the research materials for further analysis.In conclusion,MYB4 gene is involved in drought stress response,and the regulation mechanism may be related to stomata.