The National Key Facility for Crop Gene Resources and Genetic Improvement, Institute of Crop Sciences, Chinese Academy of Agricultural Sciences, Beijing, China.
Hunan Agricultural University, Changsha, China.
J Exp Bot. 2020 Jan 1;71(1):344-355. doi: 10.1093/jxb/erz409.
Wheat (Triticum aestivum) is essential for global food security. Rhizoctonia cerealis is the causal pathogen of sharp eyespot, an important disease of wheat. GATA proteins in model plants have been implicated in growth and development; however, little is known about their roles in immunity. Here, we report a defence role for a wheat LLM-domain-containing B-GATA transcription factor, TaGATA1, against R. cerealis infection and explore the underlying mechanism. Through transcriptomic analysis, TaGATA1 was identified to be more highly expressed in resistant wheat genotypes than in susceptible wheat genotypes. TaGATA1 was located on chromosome 3B and had two homoeologous genes on chromosomes 3A and 3D. TaGATA1 was found to be localized in the nucleus, possessed transcriptional activation activity, and bound to GATA-core cis-elements. TaGATA1 overexpression significantly enhanced resistance of transgenic wheat to R. cerealis, whereas silencing of TaGATA1 suppressed the resistance. Quantitative reverse transcription-PCR and ChIP-qPCR results indicated that TaGATA1 directly bound to and activated certain defence genes in host immune response to R. cerealis. Collectively, TaGATA1 positively regulates immune responses to R. cerealis through activating expression of defence genes in wheat. This study reveals a new function of plant GATAs in immunity and provides a candidate gene for improving crop resistance to R. cerealis.
小麦(Triticum aestivum)对全球粮食安全至关重要。禾旋孢腔菌是导致小麦眼斑病的病原体。模式植物中的 GATA 蛋白被认为与生长和发育有关;然而,它们在免疫中的作用知之甚少。在这里,我们报告了一种小麦 LLM 结构域包含 B-GATA 转录因子 TaGATA1 对禾旋孢腔菌感染的防御作用,并探讨了其潜在机制。通过转录组分析,发现 TaGATA1 在抗性小麦基因型中的表达水平明显高于感病小麦基因型。TaGATA1 位于 3B 染色体上,在 3A 和 3D 染色体上有两个同源基因。TaGATA1 定位于细胞核内,具有转录激活活性,并能结合 GATA 核心顺式元件。TaGATA1 的过表达显著增强了转基因小麦对禾旋孢腔菌的抗性,而 TaGATA1 的沉默则抑制了抗性。定量反转录-PCR 和 ChIP-qPCR 结果表明,TaGATA1 通过直接结合并激活宿主对禾旋孢腔菌免疫反应中的某些防御基因来发挥作用。综上所述,TaGATA1 通过激活小麦对禾旋孢腔菌的防御基因表达来正向调控对禾旋孢腔菌的免疫反应。本研究揭示了植物 GATAs 在免疫中的新功能,并为提高作物对禾旋孢腔菌的抗性提供了候选基因。