Expression Patterns And Mechanisms Analysis Of Panicle Development Related RLKs In Rice

The receptor-like kinases(RLKs)can transmit the extracellular signals into the cell through phosphorylation and dephosphorylation,which could play important roles during plant development,disease resistance and defense,etc.In preliminary studies,several RLKs which relevanted to rice development were screened in the Rice database.The digital expression patterns of six panicle development related RLKs,which are named as FTPK1,OsRLK890,OsRLK940,OsRLK040,OsRLK100,OsRLK320,were related and collected further.qRT-PCR showed that the expressions of the six RLKs were all increased during the panicle initiation,which consistent with the variations of digital expression patterns.And the expression levels of FTPK1 and OsRLK940 were 8 and 14 times higher separately at mid-heading stage compared with that in vegetative period,while the expression of OsRLK890 was almost invariant in different growth stages.Bioinformatic analysis showed that the promoter regions of six RLKs all contained several developrelated cis-elements.For instance,the promoter of FTPK1 contains 12 of GTGANTG10 elements that regulated PAL genes expression and disease resistance and 7 of W BOX elements that involved in plant disease resistance and growth.The presences of such cis elements in the promoters of RLKs indicated that the genes down stream may participate in the spatial and temporal regulation of development and reproductive progress of rich.The structures and domains prediction of these six RLKs also displayed that they contained B lectin conservative domain and two transmembrane domains,which indicated that they p-resumably have similar biology funtions.To investigate the functions of RLKs in plants,the binary expression vectors of pCAMBIA1301P-FTPK1,pCAMBIA1301P-OsRLK940 and pCAMBIA1301P-OsRLK890 were constructed,and were then transformed into the callus of rice separately by the agrobacterium mediate transformation to obtain overexpression transgenic lines.The positive transgenic plants were identified by GUS stain and molecular detection.Finally 12 of FTPK1,2 of OsRLK940 and 1 of OsRLK890 transgenic plants were harvested.The high-throughput sequencing and expression profiles analysis will be carried out using rice variety "zhonghua11" as control once the homozygous lines of transgenic rice were obtained.The researches mentioned above will provide clues for analysis the pathways and construction of regulation networks of RLKs.To further analysis the mechanisms of RLKs in plants,the physiological and chemical characters of FTPK1 were emphatically investagated.The pET-28a-FTPK1 prokaryotic expression vector was constructed,and the phosphorylation activity of the kinase was detected in vitro.The sub-localization of FTPK1 was also investigated using the transient expression vector pCAMBIA2300GFP-FTPK1,using GFP as report gene.The protoplasts of Arabidopsis were prepared and used,and the results showed that the FTPK1 was mainly located in cytoplasm and nucleus.Meanwhile,to screening the substrate of FTPK1,the DNA library was constructedusing the mixed panicles of early and middle heading stages,and yeast two-hybrid test was performed.FTPK1 bait vectors were built to do library transformation and selection of its interactors on SD-leu-trp-his-ade plates contained 0 mM 3-AT.166 positive clones were initially obtained by LacZ color reaction,and further 25 proteins were selected and identified which may interacte with FTPK1.4 of develop related proteins were selected among these 25 protein,to further reverification of their interactions with FTPK1,and 2 of these proteins were identified as positive interactors.The results derived from above will lay a solid foundation for analying the functions of RLKs,and benefit for construction and perfection of RLKs regulation networks.