castor编码百脉根(Lotus japonicus)中的离子通道蛋白,它是共生途径上的功能基因,作用于结瘤因子诱导产生的钙离子激增(calcium spiking)信号转导途径的上游,突变后不能形成根瘤。为了进一步揭示castor调控共生信号途径的分子机制,通过酵母双杂交系统在百脉根的cDNA文库中筛选可能与CASTOR相互作用的蛋白,以酵母(Saccharomy cescerevisiae)配合的方法初筛获得111个阳性克隆,经X-Gal检测进一步确认有99个蓝色克隆子,测序以及NCBIblast比对分析鉴定出JAB1、CLPA、钙调素结合的翻译延伸因子等7种可能与CASTOR相互作用的蛋白,利用RT-PCR方法检测了这些基因在接种以及不接种根瘤菌(Mesorhizobium loti)的百脉根中的表达水平,分析推测CASTOR可能与上述蛋白形成复合物参与共生信号的转导。
The castor gene encodes predictable ion channel protein which is involved in nod factor signal transduction in Lotus japonicus. CASTOR mutants undergo root hairs deformation, but do not response to nod factors with intracellular calcium spiking. In order to investigate nod factor signal mechanisms, AD-cDNA library of L. japonicus was constructed. The 111 positive clones were identified using CASTOR as the bait at pre-screening by yeast two-hybrid approach. After retest the interaction in yeast (Saccharomyces cerevisiae ) and X-Gal assay, 99 positive clones were obtained. There were seven types of proteins including CaM binding translation elongation factor characterized by sequencing and NCBI blast analysis. By using RT-PCR, the expression level of these genes was further confirmed in L.japonicus with and without inoculation of Mesorhizobium loft, it was predicted that CASTOR might form compound with these proteins in nod factor signal pathway.