National Key Laboratory of Wheat and Maize Crop Science and Key Laboratory of Regulating and Controlling Crop Growth and Development Ministry of Education, College of Agronomy, Henan Agricultural University, Zhengzhou, Henan, China.
Plant Cell Environ. 2024 Sep;47(9):3605-3618. doi: 10.1111/pce.14954. Epub 2024 May 15.
Drought, as a primary environmental factor, imposes significant constraints on developmental processes and productivity of plants. PHDs were identified as stress-responsive genes in a wide range of eukaryotes. However, the regulatory mechanisms governing PHD genes in maize under abiotic stress conditions are still largely unknown and require further investigation. Here, we identified a mutant, zmvil2, in the EMS mutant library with a C to T mutation in the exon of the Zm00001d053875 (VIN3-like protein 2, ZmVIL2), resulting in premature termination of protein coding. ZmVIL2 belongs to PHD protein family. Compared to WT, zmvil2 mutant exhibited increased sensitivity to drought stress. Consistently, overexpression of ZmVIL2 enhances drought resistance in maize. Y2H, BiFC, and Co-IP experiments revealed that ZmVIL2 directly interacts with ZmFIP37 (FKBP12-interacting protein of 37). zmfip37 knockout mutants also exhibit decreased drought tolerance. Interestingly, we demonstrated that ZmABF4 directly binds to the ZmVIL2 promoter to enhance its activity in yeast one hybrid (Y1H), electrophoretic mobility shift assay (EMSA) and dual luciferase reporter assays. Therefore, we uncovered a novel model ZmABF4-ZmVIL2/ZmFIP37 that promotes drought tolerance in maize. Overall, these findings have enriched the knowledge of the functions of PHD genes in maize and provides genetic resources for breeding stress-tolerant maize varieties.
干旱作为主要的环境因素，对植物的发育过程和生产力有很大的限制。PHD 被鉴定为真核生物中广泛的应激响应基因。然而，在非生物胁迫条件下，调节玉米中 PHD 基因的机制在很大程度上仍然未知，需要进一步研究。在这里，我们在 EMS 突变体库中鉴定到一个突变体 zmvil2，其在 Zm00001d053875（VIN3 样蛋白 2，ZmVIL2）的外显子中 C 到 T 的突变，导致蛋白质编码提前终止。ZmVIL2 属于 PHD 蛋白家族。与 WT 相比，zmvil2 突变体对干旱胁迫表现出更高的敏感性。一致地，过表达 ZmVIL2 增强了玉米的抗旱性。Y2H、BiFC 和 Co-IP 实验表明，ZmVIL2 与 ZmFIP37（37 kDa FKBP12 相互作用蛋白）直接相互作用。Zmfip37 敲除突变体也表现出降低的耐旱性。有趣的是，我们证明 ZmABF4 直接结合到 ZmVIL2 启动子上，以增强其在酵母单杂交（Y1H）、电泳迁移率变动分析（EMSA）和双荧光素酶报告基因分析中的活性。因此，我们揭示了一个新的模型 ZmABF4-ZmVIL2/ZmFIP37，它促进了玉米的耐旱性。总的来说，这些发现丰富了 PHD 基因在玉米中的功能知识，并为培育抗旱玉米品种提供了遗传资源。
