Functional Analysis Of Rice Receptor-like Protein Kinase LRK6

Plant leucine-rich-repeat receptor kinases(LRKs)are widely present in eukaryotes.LRKs play important regulatory functions in plant growth and development and resistance responses.Currently,some cloned receptor-like kinase genes are mainly derived from Arabidopsis thaliana and rice.They are involved in brassinolide signal transduction,organ size and morphology.Control,cell proliferation,seed development,floral organ decay,root development,and participation in regulating a variety of stress responses,including drought,heat tolerance and sal.A map-cloning method was used to locate a high-yield QTL(q GY2-1)that could increase the yield of indica rice Guigui 2 by 16% in a previous study.This gene cluster contains 8 genes(LRK1-8).It was found that the transgenic lines overexpressing LRK2 improved the drought resistance of rice plants by increasing root vigor.There are still many RLKs whose expression is induced by biotic stress or abiotic stress,but their specific role in regulating defense response needs further study.In this experiment,the response mechanism of LRK6 overexpression lines under heavy metal stress was studied,and the biological function of rice LRK6 gene in rice yield and stress response was discussed.Biostatistics,molecular biology,biochemistry and other biological methods were used in the study to explore the biological resistance function of LRK6 gene.The specific results are as follows:1.Construct rice LRK6 overexpression and antisense vectors;use Agrobacteriummediated transformation of rice technology system to obtain rice Nipponbare LRK6 gene overexpression transgenic seedlings and antisense expression transgenic seedlings;then use PCR amplification,sequencing,Methods such as sequence alignment verification identified homozygous transgenic lines and provided experimental materials for the subsequent study of LRK6 gene function.2.The agronomic traits of overexpressed LRK6 lines were analyzed by biostatistics,including effective tiller number,plant height,primary branch number,secondary branch number,yield per plant and total panicle number.The statistical results showed that overexpression of LRK6 increased the number of effective tillers(P < 0.05).The total panicle number was increased(P < 0.05).The plant height was reduced(P < 0.05).3.Treat the LRK6 transgenic lines with copper ion stress to explore the resistance / resistance of LRK6 to copper ion stress.Finally,the optimal concentration of copper ion stress of 0.1m M/L was selected,and the resistance function of LRK6 overexpressing lines was verified by physiological and biochemical analysis methods.It was found that the resistance of LRK6 overexpressing plants to copper stress was significantly increased,indicating that LRK6 gene is involved in regulation Copper stress response;wild-type Nipponbare plants were treated with copper ion stress,and the expression level of LRK6 gene in the plants was determined by qRT-PCR.The results showed that within a certain time and concentration range,as the time gradient and concentration gradient increased,LRK6 expression Up-regulation indicates that LRK6 overexpressing lines act as positive regulators in response to copper ion stress.4.Through qRT-PCR analysis,the expression of LRK6 gene in rice roots,rhizome junctions and various stem nodes is higher,and the expression in roots is significantly higher than other parts.GUS staining method was used to stain p LRK6:GUStransgene positive plants.The above results further confirmed that the rice LRK6 gene was expressed in each of the above parts,and the expression pattern of LRK6 gene in rice plants was analyzed.