The Medicago truncatula CRE1 cytokinin receptor regulates lateral root development and early symbiotic interaction with Sinorhizobium meliloti
The Medicago truncatula CRE1 cytokinin receptor regulates lateral root development and early symbiotic interaction with Sinorhizobium meliloti
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DOI：
10.1105/tpc.106.043778
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发表时间：
2006-10-01
期刊：
影响因子：
11.6
通讯作者：
Frugier, Florian
中科院分区：
文献类型：
--
作者：
Gonzalez-Rizzo, Silvina;Crespi, Martin;Frugier, Florian
豆科植物从其主根、侧根和根瘤发育出不同类型的侧生器官，后者取决于与苜蓿中华根瘤菌的共生相互作用。植物激素已被证明在控制这些器官发生中起作用。然而，相关的信号通路尚未确定在豆类。我们克隆并表征了蒺藜苜蓿细胞分裂素信号通路编码基因的表达。细胞分裂素受体同源物细胞分裂素应答1（Mt CRE 1）的RNA干扰导致细胞分裂素不敏感的根，其表现出侧根数量的增加和分枝的强烈减少。S.影响苜蓿根瘤菌的侵染和根瘤原基的形成。我们还确定了两个细胞分裂素信号反应调节基因，山RR 1和山RR 4，这是诱导早期的共生相互作用。S.苜蓿感染在结瘤因子信号传导途径中受影响的突变体中改变;相反，细胞分裂素对早期苜蓿蛋白NoclutinInception 1（Mt NIN）的调节依赖于Mt CRE 1。因此，细胞分裂素信号转导介导的一个单一的受体，山CRE 1，导致共生根瘤和侧根器官发生相反的控制。Mt NIN、Mt RR 1和Mt RR 4定义了在S早期激活的共同途径。苜蓿互作，允许植物细胞分裂素和细菌结瘤因子信号之间的串扰。
Legumes develop different types of lateral organs from their primary root, lateral roots and nodules, the latter depending on a symbiotic interaction with Sinorhizobium meliloti. Phytohormones have been shown to function in the control of these organogeneses. However, related signaling pathways have not been identified in legumes. We cloned and characterized the expression of Medicago truncatula genes encoding members of cytokinin signaling pathways. RNA interference of the cytokinin receptor homolog Cytokinin Response1 ( Mt CRE1) led to cytokinin- insensitive roots, which showed an increased number of lateral roots and a strong reduction in nodulation. Both the progression of S. meliloti infection and nodule primordia formation were affected. We also identified two cytokinin signaling response regulator genes, Mt RR1 and Mt RR4, which are induced early during the symbiotic interaction. Induction of these genes by S. meliloti infection is altered in mutants affected in the Nod factor signaling pathway; conversely, cytokinin regulation of the early nodulin Nodule Inception1 ( Mt NIN) depends on Mt CRE1. Hence, cytokinin signaling mediated by a single receptor, Mt CRE1, leads to an opposite control of symbiotic nodule and lateral root organogenesis. Mt NIN, Mt RR1, and Mt RR4 define a common pathway activated during early S. meliloti interaction, allowing crosstalk between plant cytokinins and bacterial Nod factors signals.