拟南芥CARK3与RCAR12相互作用的研究

An interaction of ABA receptor RCAR12 with CARK3 in Arabidopsis thaliana

植物激素ABA是植物应对非生物胁迫的响应因子,广泛参与了植物生长发育的调控.ABA结合其受体后抑制PP2Cs的磷酸酶活性,释放SnRK2s,从而启动ABA信号转导途径.本文采用酵母双杂交系统,GST-pull down技术研究蛋白质激酶CARK3与ABA受体RCAR12在体外的相互作用,结果显示CARK3和RCAR12共转入酵母后,在三缺平板上能够正常生长;经His-Tag抗体检测,CARK3与RCAR12出现明显且单一的条带.同时,采用双分子荧光互补实验研究CARK3与RCAR12在体内的相互作用,结果显示CARK3与RCAR12共转化烟草后能观察到较强的荧光.体内外实验表明,CARK3与RCAR12存在明显的相互作用,CARK3可能通过直接磷酸化ABA受体RCAR12来调控ABA信号途径的生理应答.

The phytohormone abscisic acid （ABA） is crucial for plant development and response to abiotic stress, including drought. ABA perceived by the ABA receptors, PYR/PYL/RCAR, which bound to ABA, and then recruit Protein phosphatase 2C （PP2C） to inhibit the PP2C acticity, thereby activating SNF1-RELAT- ED PROTEIN KINASE2 （SnRK2s）. Here, CARK3 and RCAR12 interact in yeast two-hybrid system and GST-pull down in vitro. The results indicated that CARK3 and RCAR12 were co-transfected into yeast and grew normally on the three-deficient plates~ CARK3 and RCAR12 showed a significant and single band, which detected by His-Tag antibody. Bimolecular fluorescence complementation （BiFC） was used to illuminate the in- teraction between CARK3 and RCAR12 in Nicotiana benthamiana in vivo. The result showed that CARK3 and RCAR12 were co-transfected into tobacco , and a strong fluorescence was observed. We could confer that CARK3 indeed interacts with RCAR12 in present study and the phosphorylation modulates the physiological re- sponse of the core ABA signaling pathway.