Molecular Characterization of LjABCG1, an ATP-Binding Cassette Protein in Lotus japonicus.
Molecular Characterization of LjABCG1, an ATP-Binding Cassette Protein in Lotus japonicus.
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DOI：
10.1371/journal.pone.0139127
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发表时间：
2015
期刊：
影响因子：
3.7
通讯作者：
Yazaki K
中科院分区：
文献类型：
--
作者：
Sugiyama A;Fukuda S;Takanashi K;Yoshioka M;Yoshioka H;Narusaka Y;Narusaka M;Kojima M;Sakakibara H;Shitan N;Sato S;Tabata S;Kawaguchi M;Yazaki K
LjABCG1 是一种模式豆科植物 Lotus japonicus 的 ATP 结合盒蛋白的全尺寸 ABCG 亚家族，据报道是在结瘤早期阶段高表达的基因，但尚未详细表征。在本研究中，我们发现茉莉酸甲酯处理对LjABCG1表达的诱导显着，报告基因实验表明LjABCG1在根瘤实质和邻近根维管组织的细胞层中向根瘤强烈表达。基于微粒体膜的分级以及通过水性两相分配的分离，LjABCG1被认为位于质膜上。分析了LjABCG1在同源和异源系统中的共生和发病机制中的生理功能。 LjABCG1 敲低的日本乳杆菌植物在根瘤形成方面没有表现出明显的表型差异，在防御丁香假单胞菌方面也没有表现出明显的表型差异。相反，当LjABCG1在拟南芥pdr8-1突变体中表达时，马铃薯晚疫病病原体致病疫霉在LjABCG1/pdr8-1中的渗透频率比在pdr8-1植物中显着降低。这一发现表明，LjABCG1 至少部分补充了拟南芥中 pdr8 的表型，表明该蛋白在植物-微生物相互作用中发挥多重作用。
LjABCG1, a full-size ABCG subfamily of ATP-binding cassette proteins of a model legume, Lotus japonicus, was reported as a gene highly expressed during the early stages of nodulation, but have not been characterized in detail. In this study we showed that the induction of LjABCG1 expression was remarkable by methyl jasmonate treatment, and reporter gene experiments indicated that LjABCG1 was strongly expressed in the nodule parenchyma and cell layers adjacent to the root vascular tissue toward the nodule. LjABCG1 was suggested to be localized at the plasma membrane based on the fractionation of microsomal membranes as well as separation via aqueous two-phase partitioning. The physiological functions of LjABCG1 in symbiosis and pathogenesis were analyzed in homologous and heterologous systems. LjABCG1 knock-down L. japonicus plants did not show clear phenotypic differences in nodule formation, and not in defense against Pseudomonas syringae, either. In contrast, when LjABCG1 was expressed in the Arabidopsis pdr8-1 mutant, the penetration frequency of Phytophthora infestans, a potato late blight pathogen, was significantly reduced in LjABCG1/pdr8-1 than in pdr8-1 plants. This finding indicated that LjABCG1, at least partially, complemented the phenotype of pdr8 in Arabidopsis, suggesting the multiple roles of this protein in plant-microbe interactions.