Department of Horticulture, Oregon State University, Corvallis, OR, USA.
Phytopathology. 2011 Nov;101(11):1311-21. doi: 10.1094/PHYTO-03-11-0087.
The plant hormone ethylene regulates fruit ripening, other developmental processes, and a subset of defense responses. Here, we show that 1-aminocyclopropane-1-carboxylic acid synthase (ACS)-silenced apple (Malus domestica) fruit that express a sense construct of ACS were more susceptible to Botrytis cinerea than untransformed apple, demonstrating that ethylene strengthens fruit resistance to B. cinerea infection. Because ethylene response factors (ERFs) are known to contribute to resistance against B. cinerea via the ethylene-signaling pathway, we cloned four ERF cDNAs from fruit of M. domestica: MdERF3, -4, -5, and -6. Expression of all four MdERF mRNAs was ethylene dependent and induced by wounding or by B. cinerea infection. B. cinerea infection suppressed rapid induction of wound-related MdERF expression. MdERF3 was the only mRNA induced by wounding and B. cinerea infection in ACS-suppressed apple fruit, although its induction was reduced compared with wild-type apple. Promoter regions of all four MdERF genes were cloned and putative cis-elements were identified in each promoter. Transient expression of MdERF3 in tobacco increased expression of the GCC-box containing gene chitinase 48.
植物激素乙烯调节果实成熟、其他发育过程和防御反应的一部分。在这里，我们表明，沉默 1-氨基环丙烷-1-羧酸合酶（ACS）的苹果（Malus domestica）果实表达 ACS 的感测结构比未转化的苹果更容易感染 Botrytis cinerea，表明乙烯增强了果实对 B. cinerea 感染的抗性。由于乙烯反应因子（ERFs）已知通过乙烯信号通路有助于对 B. cinerea 的抗性，我们从 M. domestica 果实中克隆了四个 ERF cDNA：MdERF3、-4、-5 和 -6。这四个 MdERF mRNA 的表达均依赖于乙烯，并受创伤或 B. cinerea 感染诱导。B. cinerea 感染抑制了与创伤相关的 MdERF 表达的快速诱导。在 ACS 抑制的苹果果实中，只有 MdERF3 被创伤和 B. cinerea 感染诱导，尽管与野生型苹果相比，其诱导降低了。克隆了所有四个 MdERF 基因的启动子区域，并在每个启动子中鉴定了假定的顺式元件。MdERF3 在烟草中的瞬时表达增加了含有 GCC 盒的基因几丁质酶 48 的表达。
