The Molecular Basis of Host Specialization in Bean Pathovars of Pseudomonas syringae
The Molecular Basis of Host Specialization in Bean Pathovars of Pseudomonas syringae
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DOI：
10.1094/mpmi-08-11-0218
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发表时间：
2012-07-01
影响因子：
3.5
通讯作者：
Dangl, Jeffery L.
中科院分区：
文献类型：
--
作者：
Baltrus, David A.;Nishimura, Marc T.;Dangl, Jeffery L.
生物营养型植物病原体通常限于其适应的宿主范围。近几十年来，研究已经梳理了植物先天免疫的种内变异的一般分子基础，通常涉及受体蛋白，其能够感知病原体相关的分子模式或病原体的无毒激发子作为防御诱导的触发物。然而，关于改变宿主范围的进化和分子因素在密切相关的植物病原体分离株的一般共识一直比较难以捉摸。在这里，通过基因组比较和遗传操作，我们调查的基本机制，结构主机范围之间的密切相关的菌株分离的假单胞菌从不同的豆类主机。虽然III型分泌独立的毒力因子在这三个菌株中是保守的，我们发现，存在两个基因编码III型效应子（跳C7和hopM1）和另一个（avrB2）的情况下，可能有助于宿主范围之间的差异的致病变种glycoprotein和菜豆。这些发现加强了这样一个想法，即一个复杂的遗传基础的植物病原体的寄主范围的演变。这种复杂性甚至存在于宿主微生物相互作用中，其特征在于宿主和其适应的病原体之间的差异相对较小。
Biotrophic phytopathogens are typically limited to their adapted host range. In recent decades, investigations have teased apart the general molecular basis of intraspecific variation for innate immunity of plants, typically involving receptor proteins that enable perception of pathogen-associated molecular patterns or avirulence elicitors from the pathogen as triggers for defense induction. However, general consensus concerning evolutionary and molecular factors that alter host range across closely related phytopathogen isolates has been more elusive. Here, through genome comparisons and genetic manipulations, we investigate the underlying mechanisms that structure host range across closely related strains of Pseudomonas syringae isolated from different legume hosts. Although type III secretionindependent virulence factors are conserved across these three strains, we find that the presence of two genes encoding type III effectors (hop C7 and hopM1) and the absence of another (avrB2) potentially contribute to host range differences between pathovars glycinea and phaseolicola. These findings reinforce the idea that a complex genetic basis underlies host range evolution in plant pathogens. This complexity is present even in host microbe interactions featuring relatively little divergence among both hosts and their adapted pathogens.