Knock out of transcription factor WRKY53 thickens sclerenchyma cell walls, confers bacterial blight resistance
Knock out of transcription factor WRKY53 thickens sclerenchyma cell walls, confers bacterial blight resistance
复制标题
敲除转录因子 WRKY53 会使厚壁组织细胞壁增厚，赋予白叶枯病抗性。
DOI：
10.1093/plphys/kiab400
复制
发表时间：
2021-08-23
期刊：
影响因子：
7.4
通讯作者：
Yuan, Meng
中科院分区：
文献类型：
--
作者：
Xie, Wenya;Ke, Yinggen;Yuan, Meng
植物细胞壁是抵御病原菌入侵的第一道物理屏障，植物通过包裹细胞壁来加固细胞壁，从而抑制病原菌的侵染。水稻白叶枯病是由黄单胞菌白叶枯病病毒引起的一种毁灭性病害。Xoo），其通常通过根管进入水稻叶片并通过木质部遍布整个植物。Xoo与维管束木质部导管周围的细胞相互作用，但水稻是否加强厚壁组织细胞壁以阻止病原体增殖尚不清楚。在这里，我们发现，WRKY蛋白，OsWRKY53，负赋予抗性Xoo通过加强厚壁组织细胞壁的维管束。OsMYB63作为转录激活因子，促进三个次生细胞壁相关纤维素合成酶基因的表达，从而促进纤维素积累，导致厚壁组织细胞壁增厚。OsWRKY53和OsMYB63均在叶片维管束的厚壁组织细胞中大量表达。OsWRKY53作为转录抑制因子发挥作用，并在OsMYB63的基因上游起作用以抑制其表达。OsWRKY53过表达和OsMYB63敲除植株的厚壁组织细胞壁较薄，表现出对Xoo的敏感性，而OsWRKY53敲除和OsMYB63过表达植株的厚壁组织细胞壁较厚，表现出对Xoo的抗性。这些结果表明，修改这些候选基因提供了一个策略，以提高水稻对细菌病原体的抗性。
Plant cell walls are the first physical barrier against pathogen invasion, and plants thicken the cell wall to strengthen it and restrain pathogen infection. Bacterial blight is a devastating rice (Oryza sativa) disease caused by Xanthomonas oryzae pv. oryzae (Xoo), which typically enters the rice leaf through hydathodes and spreads throughout the plant via the xylem. Xoo interacts with cells surrounding the xylem vessel of a vascular bundle, but whether rice strengthens the sclerenchyma cell walls to stop pathogen proliferation is unclear. Here, we found that a WRKY protein, OsWRKY53, negatively confers resistance to Xoo by strengthening the sclerenchyma cell walls of the vascular bundle. OsMYB63 acts as a transcriptional activator and promotes the expression of three secondary cell wall-related cellulose synthase genes to boost cellulose accumulation, resulting in thickened sclerenchyma cell walls. Both OsWRKY53 and OsMYB63 are abundantly expressed in sclerenchyma cells of leaf vascular bundles. OsWRKY53 functions as a transcriptional repressor and acts genetically upstream of OsMYB63 to suppress its expression. The OsWRKY53-overexpressing and OsMYB63 knockout plants had thinner sclerenchyma cell walls, showing susceptibility to Xoo, while the OsWRKY53 knockout and OsMYB63-overexpressing plants had thicker sclerenchyma cell walls, exhibiting resistance to Xoo. These results suggest that modifying these candidate genes provides a strategy to improve rice resistance to bacterial pathogens.