The Xo1 locus in the heirloom rice variety Carolina Gold Select confers resistance to bacterial leaf streak and bacterial blight, caused by Xanthomonas oryzae pv. oryzicola and X. oryzae pv. oryzae, respectively. Resistance is triggered by pathogen-delivered transcription activator-like effectors (TALEs) independent of their ability to activate transcription and is suppressed by truncated variants called truncTALEs, common among Asian strains. By transformation of the susceptible variety Nipponbare, we show that one of 14 nucleotide-binding, leucine-rich repeat (NLR) protein genes at the locus, with a zinc finger BED domain, is the Xo1 gene. Analyses of published transcriptomes revealed that the Xo1-mediated response is more similar to those mediated by two other NLR resistance genes than it is to the response associated with TALE-specific transcriptional activation of the executor resistance gene Xa23 and that a truncTALE dampens or abolishes activation of defense-associated genes by Xo1. In Nicotiana benthamiana leaves, fluorescently tagged Xo1 protein, like TALEs and truncTALEs, localized to the nucleus. And endogenous Xo1 specifically coimmunoprecipitated from rice leaves with a pathogen-delivered, epitope-tagged truncTALE. These observations suggest that suppression of Xo1-function by truncTALEs occurs through direct or indirect physical interaction. They further suggest that effector coimmunoprecipitation may be effective for identifying or characterizing other resistance genes.

传家宝水稻品种Carolina Gold Select中的Xo1基因座赋予了对由黄单胞菌（Xanthomonas oryzae pv）引起的细菌叶片条纹和枯萎病的抗性。oryzicola和X. oryzae pv。菌，分别。抗性由病原体传递的转录激活因子样效应物（TALE）触发，而与它们激活转录的能力无关，并被亚洲菌株中常见的被截短的变体truncTALE抑制。通过转化易感品种Nipponbare，我们显示在Xz1位点是具有锌指BED结构域的14个核苷酸结合，富含亮氨酸的重复序列（NLR）蛋白基因之一基因。对已发表的转录组的分析表明，Xo1介导的应答与其他两个NLR抗性基因介导的应答更相似，而不是与执行者抗性基因Xa23的TALE特异性转录激活相关的应答，并且truncTALE抑制或废除了活化Xo1对防御相关基因的鉴定。在烟草中叶片中，荧光标记的Xo1蛋白（如TALE和truncTALEs）位于细胞核。内源性Xo1通过与病原体传递的抗原决定簇标记的truncTALE从稻叶中特异性免疫共沉淀。这些观察结果表明，truncTALE对Xo1功能的抑制作用是通过直接或间接的物理相互作用而发生的。他们进一步表明，效应物共免疫沉淀法可能对鉴定或表征其他抗性基因有效。