Engineering Broad-Spectrum Bacterial Blight Resistance by Simultaneously Disrupting Variable TALE-Binding Elements of Multiple Susceptibility Genes in Rice
Engineering Broad-Spectrum Bacterial Blight Resistance by Simultaneously Disrupting Variable TALE-Binding Elements of Multiple Susceptibility Genes in Rice
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DOI：
10.1016/j.molp.2019.08.006
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发表时间：
2019-11-04
期刊：
影响因子：
27.5
通讯作者：
Chen, Gongyou
中科院分区：
文献类型：
--
作者：
Xu, Zhengyin;Xu, Xiameng;Chen, Gongyou
米黄单胞菌 pv.米曲霉 (Xoo) 是水稻白叶枯病的致病因子，它利用类转录激活因子效应子 (TALE) 诱导假定糖转运蛋白基因 OsSWEET 家族的表达，该基因在赋予水稻植物疾病易感性 (S) 方面发挥作用。为了设计广谱白叶枯病抗性，我们使用 CRISPR/Cas9 介导的基因编辑来破坏水稻品种中两个 S 基因 OsSWEET11 和 OsSWEET14 的 TALE 结合元件 (EBE)。 Kitaake，含有 Xa25/OsSWEET13 隐性抗性等位基因。工程水稻品系 MS14K 对除少数例外的大多数 Xoo 菌株表现出广谱抗性，表明相容菌株可能含有新的 TALE。我们鉴定出两个类 PthXo2 TALE，Tal5LN18 和 Tal7PXO61，分别作为相容 Xoo 菌株 LN18 和 PXO61 的主要毒力因子，并发现 Xoo 编码至少五种类型的 PthXo2 样效应子。鉴于 PthXo2/PthXo2.1 以 OsSWEET13 为转录激活目标，对 3000 个水稻品种的基因组进行了 OsSWEET13 启动子 EBE 变异分析，并鉴定了 10 个 Xa25 样单倍型。我们发现Tal5（LN18）和Tal7（PXO61）在OsSWEET13启动子中结合略有不同的EBE序列以激活其表达。然后使用 CRISPR/Cas9 技术在 MS14K 中 OsSWEET13 启动子的 EBE 中生成 InDels，以创建具有三个编辑的 OsSWEET EBE 的新种质，并对所有测试的 Xoo 菌株具有广谱抗性。总的来说，我们的研究结果说明了如何通过丧失植物中效应子触发的易感性来解除 TALE-S 共同进化基因座的武装，从而产生广谱抗性。
Xanthomonas oryzae pv. oryzae (Xoo), the causal agent of bacterial blight of rice, employs the transcription activator-like effectors (TALEs) to induce the expression of the OsSWEET family of putative sugar transporter genes, which function in conferring disease susceptibility (S) in rice plants. To engineer broadspectrum bacterial blight resistance, we used CRISPR/Cas9-mediated gene editing to disrupt the TALE-binding elements (EBEs) of two S genes, OsSWEET11 and OsSWEET14, in rice cv. Kitaake, which harbors the recessive resistance allele of Xa25/OsSWEET13. The engineered rice line MS14K exhibited broadspectrum resistance to most Xoo strains with a few exceptions, suggesting that the compatible strains may contain new TALEs. We identified two PthXo2-like TALEs, Tal5LN18 and Tal7PXO61, as major virulence factors in the compatible Xoo strains LN18 and PXO61, respectively, and found that Xoo encodes at least five types of PthXo2-like effectors. Given that PthXo2/PthXo2.1 target OsSWEET13 for transcriptional activation, the genomes of 3000 rice varieties were analyzed for EBE variationsin the OsSWEET13 promoter, and 10 Xa25-like haplotypes were identified. We found that Tal5(LN18) and Tal7(PXO61) bind slightly different EBE sequences in the OsSWEET13 promoter to activate its expression. CRISPR/Cas9 technology was then used to generate InDels in the EBE of the OsSWEET13 promoter in MS14K to creat a new germplasm with three edited OsSWEET EBEs and broad-spectrum resistance against all Xoo strains tested. Collectively, our findings illustrate how to disarm TALE-S co-evolved loci to generate broad-spectrumresistance through the loss of effector-triggered susceptibility in plants.