A bacterial sensor of plant cell contact controls the transcriptional induction of Ralstonia solanacearum pathogenicity genes
A bacterial sensor of plant cell contact controls the transcriptional induction of Ralstonia solanacearum pathogenicity genes
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DOI：
10.1093/emboj/19.10.2304
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发表时间：
2000-05-15
期刊：
影响因子：
11.4
通讯作者：
Genin, S
中科院分区：
文献类型：
--
作者：
Aldon, D;Brito, B;Genin, S
植物病原菌青枯雷尔氏菌的hrp基因是致病力的关键决定因素，它们编码一种III型蛋白分泌机制，参与细菌-植物相互作用的介质的分泌。这些hrp基因受hrpB调控基因的遗传控制，当细菌与植物细胞悬浮液共培养时，hrpB调控基因的表达被诱导。在本研究中，我们使用HRP-GFP转录融合来证明hrpB和LII型分泌基因的表达是对细菌-植物细胞接触的特异性诱导。这种接触依赖的hrpB基因表达的诱导需要外膜蛋白PrhA，而不是一个功能性的III型分泌装置。遗传证据表明，PrhA是植物细胞壁中存在的非扩散信号的细菌受体的第一个例子，它触发了细菌毒力基因的转录激活。
The hrp genes of the plant pathogen Ralstonia solanacearum are key pathogenicity determinants; they encode a type III protein secretion machinery involved in the secretion of mediators of the bacterium-plant interaction. These hrp genes are under the genetic control of the hrpB regulatory gene, expression of which is induced when bacteria are co-cultivated with plant cell suspensions. In this study, we used hrp-gfp transcriptional fusions to demonstrate that the expression of the hrpB and type LII secretion genes is specifically induced in response to the bacterium-plant cell contact. This contact-dependent induction of hrpB gene expression requires the outer membrane protein PrhA, but not a functional type III secretion apparatus. Genetic evidence indicates that PrhA constitutes the first example of a bacterial receptor for a non-diffusible signal present in the plant cell wall and which triggers the transcriptional activation of bacterial virulence genes.