Plants have developed various mechanisms for avoiding pathogen invasion, including resistance (R) genes. Most R genes encode nucleotide-binding domain and leucine-rich repeat containing proteins (NLRs). Here, we report the isolation of three new bacterial blight R genes in rice, Xa1-2, Xa14, and Xa31(t), which were allelic to Xa1 and encoded atypical NLRs with unique central tandem repeats (CTRs). We also found that Xa31(t) was the same gene as Xa1-2. Although Xa1-2 and Xa14 conferred different resistance spectra, their performance could be attenuated by iTALEs, as has previously been reported for Xa1. XA1, XA1-2, XA14, and non-resistant RGAF differed mainly in the substructure of the leucine-rich repeat domain. They all contained unique CTRs and belonged to the CTR-NLRs, which existed only in Gramineae. We also found that interactions among these genes led to differing resistance performance. In conclusion, our results uncover a unique locus in rice consisting of at least three multiple alleles (Xa1, Xa1-2, and Xa14) that encode CTR-NLRs and confer resistance to Xanthomonas oryzae pv. oryzae (Xoo).

植物已经发展出各种机制来避免病原体入侵，包括抗性( R ) 基因。大多数 R基因编码核苷酸结合域和富含亮氨酸重复序列的蛋白质 (NLR)。在这里，我们报告了水稻中三个新的白叶枯病R基因Xa1-2、Xa14和Xa31 ( t ) 的分离，它们是Xa1 的等位基因并编码具有独特中央串联重复序列 (CTR) 的非典型 NLR。我们还发现Xa31 ( t ) 与Xa1-2是相同的基因。尽管Xa1-2和Xa14赋予不同的电阻谱，它们的性能可能会被 iTALEs 减弱，正如之前对Xa1 的报道。XA1、XA1-2、XA14 和非抗性 RGAF 的不同主要在于富含亮氨酸的重复结构域的亚结构。它们都包含独特的 CTR，属于仅存在于禾本科的 CTR-NLR。我们还发现这些基因之间的相互作用导致了不同的抗性表现。总之，我们的结果揭示了水稻中一个独特的基因座，该基因座由至少三个多重等位基因（Xa1、  Xa1-2和 Xa14）组成，这些基因编码 CTR-NLR 并赋予对米黄单胞菌pv 的抗性。米（Xoo）。