A high-throughput, near-saturating screen for type III effector genes from Pseudomonas syringae
A high-throughput, near-saturating screen for type III effector genes from Pseudomonas syringae
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DOI：
10.1073/pnas.0409660102
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发表时间：
2005-02-15
影响因子：
11.1
通讯作者：
Dangl, JL
中科院分区：
文献类型：
--
作者：
Chang, JH;Urbach, JM;Dangl, JL
假单胞菌菌株在感染过程中向植物细胞中递送可变数量的III型效应蛋白。这些蛋白质是毒力所必需的，因为不能传递它们的菌株是非致病性的。我们实施了一个全基因组，高通量筛选，以确定第三型效应基因。该筛选依赖于FACS和阿拉伯糖诱导的hrpL或因子来自动鉴定和克隆HrpL调节的基因。我们确定候选基因是否编码III型效应蛋白，通过创建和测试全长蛋白融合到一个名为Delta79AvrRpt2的报告，当融合到已知的III型效应蛋白，是易位和elevant过敏反应在拟南芥叶片表达的RPS2植物抗病蛋白。因此，Delta79AvrRpt2是III型分泌系统依赖性易位的标志物，这是定义III型效应蛋白的最关键标准。我们描述了我们的屏幕和收集的III型效应蛋白从两个致病变种的A pathovars的。这一严格的功能标准定义了29种来自P.番茄疫霉致病变种19株。菜豆小种6.我们的数据提供了完整的功能注释的hrpL依赖的III型效应器套件从两个测序的A pathovars和显示，III型效应器蛋白套件是高度可变的，在这种病原体，大概反映了进化选择施加的各种宿主植物。
Pseudomonas syringae strains deliver variable numbers of type III effector proteins into plant cells during infection. These proteins are required for virulence, because strains incapable of delivering them are nonpathogenic. We implemented a whole-genome, high-throughput screen for identifying A syringae type III effector genes. The screen relied on FACS and an arabinose-inducible hrpL or factor to automate the identification and cloning of HrpL-regulated genes. We determined whether candidate genes encode type III effector proteins by creating and testing full-length protein fusions to a reporter called Delta79AvrRpt2 that, when fused to known type III effector proteins, is translocated and elicits a hypersensitive response in leaves of Arabidopsis thaliana expressing the RPS2 plant disease resistance protein. Delta79AvrRpt2 is thus a marker for type III secretion system-dependent translocation, the most critical criterion for defining type III effector proteins. We describe our screen and the collection of type III effector proteins from two pathovars of A syringae. This stringent functional criteria defined 29 type III proteins from P. syringae pv. tomato, and 19 from P. syringae pv. phaseolicola race 6. Our data provide full functional annotation of the hrpL-dependent type III effector suites from two sequenced A syringae pathovars and show that type III effector protein suites are highly variable in this pathogen, presumably reflecting the evolutionary selection imposed by the various host plants.