Xia Ye, Gao Qing-Ming, Yu Keshun, Lapchyk Ludmila, Navarre DuRoy, Hildebrand David, Kachroo Aardra, Kachroo Pradeep
Department of Plant Pathology, University of Kentucky, Lexington, KY 40546, USA.
Cell Host Microbe. 2009 Feb 19;5(2):151-65. doi: 10.1016/j.chom.2009.01.001.
Systemic acquired resistance (SAR), initiated by a plant upon recognition of microbial effectors, involves generation of a mobile signal at the primary infection site, which translocates to and activates defense responses in distal tissues via unknown mechanism(s). We find that an acyl carrier protein, ACP4, is required to perceive the mobile SAR signal in distal tissues of Arabidopsis. Although acp4 plants generated the mobile signal, they failed to induce the systemic immunity response. Defective SAR in acp4 plants was not due to impairment in salicylic acid (SA)-, methyl SA-, or jasmonic acid-mediated plant hormone signaling pathways but was associated with the impaired cuticle of acp4 leaves. Other cuticle-impairing genetic mutations or physical removal of the cuticle also compromised SAR. This cuticular requirement was relevant only during mobile signal generation and its translocation to distal tissues. Collectively, these data suggest an active role for the plant cuticle in SAR-related molecular signaling.
系统获得性抗性（SAR）是植物在识别微生物效应子时启动的，它涉及在初次感染部位产生一种可移动信号，该信号通过未知机制转移到远端组织并激活其中的防御反应。我们发现，一种酰基载体蛋白ACP4是拟南芥远端组织中感知可移动SAR信号所必需的。尽管acp4植株产生了可移动信号，但它们未能诱导系统免疫反应。acp4植株中SAR缺陷并非由于水杨酸（SA）、甲基水杨酸或茉莉酸介导的植物激素信号通路受损，而是与acp4叶片角质层受损有关。其他导致角质层受损的基因突变或角质层的物理去除也会损害SAR。这种对角质层的需求仅在可移动信号产生及其向远端组织转移期间才相关。总体而言，这些数据表明植物角质层在与SAR相关的分子信号传导中发挥着积极作用。
