LysM domains mediate lipochitin-oligosaccharide recognition and Nfr genes extend the symbiotic host range
LysM domains mediate lipochitin-oligosaccharide recognition and Nfr genes extend the symbiotic host range
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DOI：
10.1038/sj.emboj.7601826
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发表时间：
2007-09-05
期刊：
影响因子：
11.4
通讯作者：
Stougaard, Jens
中科院分区：
文献类型：
--
作者：
Radutoiu, Simona;Madsen, Lene H.;Stougaard, Jens
豆科植物-根瘤菌共生是由宿主/非宿主决定因子控制的选择性细胞识别的一个例子。单个细菌菌株具有不同的宿主范围，使得能够对有限的一组豆类物种进行繁殖，反之亦然。本研究表明，百脉根Nfr 1和Nfr 5 Nod因子受体基因在蒺藜苜蓿和苜蓿中的表达与百脉根Nfr 1和Nfr 5受体基因的表达相关。filicaulis，将它们的宿主范围扩展到包括通常感染L. - 是的结果，共生程序被诱导，结节发育并形成感染线。利用L.突变体和L.和L. filicaulis NFR 1和NFR 5，我们进一步证明NFR 1和NFR 5受体的LysM结构域介导细菌Nod因子信号的感知，并且识别依赖于脂几丁质寡糖Nod因子的结构。我们发现，NFR 5的LysM 2结构域中的单个氨基酸变异改变了DZL菌株合成的Nod因子的识别，并表明细菌脂几丁质寡糖信号分子的可能结合位点。
Legume-Rhizobium symbiosis is an example of selective cell recognition controlled by host/non-host determinants. Individual bacterial strains have a distinct host range enabling nodulation of a limited set of legume species and vice versa. We show here that expression of Lotus japonicus Nfr1 and Nfr5 Nod-factor receptor genes in Medicago truncatula and L. filicaulis, extends their host range to include bacterial strains, Mesorhizobium loti or DZL, normally infecting L. japonicus. As a result, the symbiotic program is induced, nodules develop and infection threads are formed. Using L. japonicus mutants and domain swaps between L. japonicus and L. filicaulis NFR1 and NFR5, we further demonstrate that LysM domains of the NFR1 and NFR5 receptors mediate perception of the bacterial Nod-factor signal and that recognition depends on the structure of the lipochitin-oligosaccharide Nod-factor. We show that a single amino-acid variation in the LysM2 domain of NFR5 changes recognition of the Nod-factor synthesized by the DZL strain and suggests a possible binding site for bacterial lipochitin-oligosaccharide signal molecules.