School of Agriculture and Biology/State Key Laboratory of Microbial Metabolism, Shanghai Jiao Tong University, Shanghai, China.
School of Agriculture and Biology/Key Laboratory of Urban Agriculture by Ministry of Agriculture of China, Shanghai Jiao Tong University, Shanghai, China.
J Exp Bot. 2021 Apr 2;72(8):3249-3262. doi: 10.1093/jxb/erab054.
Xa1-mediated resistance to rice bacterial blight, caused by Xanthomonas oryzae pv. oryzae (Xoo), is triggered by transcription activator-like effectors (TALEs) and suppressed by interfering TALEs (iTALEs). TALEs interact with the rice transcription factor OsTFIIAγ1 or OsTFIIAγ5 (Xa5) to activate expression of target resistance and/or susceptibility genes. However, it is not clear whether OsTFIIAγ is involved in TALE-triggered and iTALE-suppressed Xa1-mediated resistance. In this study, genome-edited mutations in OsTFIIAγ5 or OsTFIIAγ1 of Xa1-containing rice 'IRBB1' and Xa1-transgenic plants of xa5-containing rice 'IRBB5' did not impair the activation or suppression of Xa1-mediated resistance. Correspondingly, the expression pattern of Xa1 in mutated OsTFIIAγ5 and OsTFIIAγ1 rice lines and 'IRBB1' rice was similar. In contrast, the expression of OsSWEET11 was repressed in rice lines mutated in OsTFIIAγ5 and OsTFIIAγ1. Bimolecular fluorescence complementation (BiFC) and co-immunoprecipitation assays showed that both TALE PthXo1 and iTALE Tal3a interacted with OsTFIIAγ1 and OsTFIIAγ5 in plant nuclei. These results indicated that TALE-triggered and iTALE-suppressed Xa1-mediated resistance to bacterial blight is independent of OsTFIIAγ1 or OsTFIIAγ5 in rice, and suggest that an unknown factor is potentially involved in the interaction of Xa1, TALEs and iTALEs.
Xa1 介导的对由稻黄单胞菌引起的细菌性条斑病的抗性（Xoo）是由转录激活子样效应物（TALEs）触发的，并被干扰 TALEs（iTALEs）所抑制。TALEs 与水稻转录因子 OsTFIIAγ1 或 OsTFIIAγ5（Xa5）相互作用，激活靶标抗性和/或敏感性基因的表达。然而，目前尚不清楚 OsTFIIAγ 是否参与 TALE 触发和 iTALE 抑制的 Xa1 介导的抗性。在本研究中，含有 Xa1 的水稻‘IRBB1’和含有 Xa1 的转 xa5 水稻‘IRBB5’的 OsTFIIAγ5 或 OsTFIIAγ1 基因组编辑突变并未损害 Xa1 介导的抗性的激活或抑制。相应地，突变 OsTFIIAγ5 和 OsTFIIAγ1 水稻系和‘IRBB1’水稻中 Xa1 的表达模式相似。相比之下，OsSWEET11 的表达在 OsTFIIAγ5 和 OsTFIIAγ1 突变体水稻系中受到抑制。双分子荧光互补（BiFC）和共免疫沉淀测定表明，TALE PthXo1 和 iTALE Tal3a 都与植物核内的 OsTFIIAγ1 和 OsTFIIAγ5 相互作用。这些结果表明，TALE 触发和 iTALE 抑制的 Xa1 介导的细菌性条斑病抗性在水稻中不依赖于 OsTFIIAγ1 或 OsTFIIAγ5，并且表明一个未知的因素可能参与了 Xa1、TALEs 和 iTALEs 的相互作用。
