Ethylene response factor (ERF) Group VII members generally function in regulating plant growth and development, abiotic stress responses, and plant immunity in Arabidopsis; however, the details of the regulatory mechanism by which Group VII ERFs mediate plant immune responses remain elusive. Here, we characterized one such member, ERF72, as a positive regulator that mediates resistance to the necrotrophic pathogen Botrytis cinerea. Compared with the wild-type (WT), the erf72 mutant showed lower camalexin concentration and was more susceptible to B. cinerea, while complementation of ERF72 in erf72 rescued the susceptibility phenotype. Moreover, overexpression of ERF72 in the WT promoted camalexin biosynthesis and increased resistance to B. cinerea. We identified the camalexin-biosynthesis genes PAD3 and CYP71A13 and the transcription factor WRKY33 as target genes of ERF72. We also determined that MPK3 and MPK6 phosphorylated ERF72 at Ser151 and improved its transactivation activity, resulting in increased camalexin concentration and increased resistance to B. cinerea. Thus, ERF72 acts in plant immunity to coordinate camalexin biosynthesis both directly by regulating the expression of biosynthetic genes and indirectly by targeting WRKK33.

中文翻译：

---

MPK3/MPK6 介导的 ERF72 磷酸化通过直接和间接激活 camalexin 生物合成酶的转录正调节对灰霉病菌的抗性

乙烯反应因子 (ERF) 第 VII 组成员通常在拟南芥中调节植物生长发育、非生物胁迫反应和植物免疫；然而，第 VII 组 ERF 介导植物免疫反应的调节机制的细节仍然难以捉摸。在这里，我们将其中一个成员 ERF72 定性为一种正调节因子，可介导对坏死性病原体灰霉病菌的抗性。与野生型（WT）相比，erf72 突变体显示出较低的camalexin 浓度并且对灰霉病菌更敏感，而erf72 中的ERF72 互补挽救了易感性表型。此外，在 WT 中过表达 ERF72 促进了 camalexin 的生物合成并增加了对 B. cinerea 的抗性。我们将camalexin生物合成基因PAD3和CYP71A13以及转录因子WRKY33鉴定为ERF72的靶基因。我们还确定 MPK3 和 MPK6 在 Ser151 处磷酸化 ERF72 并提高其反式激活活性，从而增加 camalexin 浓度并增加对 B. cinerea 的抗性。因此，ERF72 在植物免疫中发挥作用，通过调节生物合成基因的表达直接和通过靶向 WRKK33 间接协调camalexin 的生物合成。