Cloning And Functional Studies Of SiSERK1 Gene Of Foxtail Millet(Setaria Italica)

Somatic embryogenesis receptor-like kinases(SERKs)are a family of structurally conserved genes,which widely exist in the plant kingdom.They are involved in regulating the response of plants to biological and abiotic stresses and affecting plant growth and development.In recent years,foxtail millet,an important food crop in our country,has been affected by various biological and abiotic stress.In order to change this situation,SiSERK1 gene and its promoter are cloned in this study,and the coding sequence(CDS)and promoter sequence of SiSERK1 gene are analyzed by bioinformatics,mainly including the physical and chemical properties,hydrophobicity,subcellular localization,secondary structure and phosphorylation site of SiSERK1 protein.Then,SiSERK1 overexpression vector is constructed by Gateway technology and transferred into brassinolactone(BR)receptor deletion mutant bri1-5 for subcellular localization,tissue localization and expression analysis,phenotype analysis of seedlings and mature plants,BL treatment was applied externally to detect the expression levels of BR synthesis genes CPD and DWF4.Then Pst DC3000 treatment was performed to detect the CFU(Colony-Forming Units)value of the pathogen,the changes in plant height of transgenic plants after treatment,stomatal opening and electrical conductivity of the plant after treatment,and mannitol and Na Cl treatment are used to detect the root length and hypocotyl changes of the three materials,and finally to further determine the function of the gene,the main conclusions are as follows:1.In this study,SiSERK1 overexpressed strain is obtained by Gateway technology and SiSERK1 overexpressed material in BR receptor mutant bri1-5 is obtained by flower immersion method.2.SiSERK1 is instantaneously transfected into Bens tobacco,and observed by laser confocal microscopy,it is found that the protein encoded by SiSERK1 is located in the cell membrane,which is consistent with the prediction results of bioinformatics.SiSERK1 is a membrane protein.3.SiSERK1 gene is similar to AtSERK gene in Arabidopsis thaliana,participating in BR signaling pathway,and SiSERK1 overexpressed plants can partially restore the bri1-5 phenotype.4.In this study,by using Pst DC3000 treatment,it is found that the expression level of immune marker genes in overexpressed plants of SiSERK1 gene is significantly higher than that in bri1-5,indicating that SiSERK1 gene is involved in the immune response of plants.5.The expression of SiSERK1 gene is induced by ABA and light intensity,and there are some differences in the expression of SiSERK1 gene under different ABA concentration and light intensity.6.SiSERK1 overexpressed plants are treated for drought stress and salt stress,and it is found that SiSERK1 gene was involved in regulating the response of plants to drought stress,but not to salt stress.This study finally proves that SiSERK1 gene is involved in BR signaling pathway and immune signaling pathway in plants.It will provide experimental materials and new ideas for studyingSERK genes and stress resistance of foxtail millet in the future.