Plant Molecular Genetics Department, Centro Nacional de Biotecnología-Consejo Superior de Investigaciones Científicas Madrid, Spain.
Front Plant Sci. 2013 Apr 5;4:72. doi: 10.3389/fpls.2013.00072. eCollection 2013.
An extraordinary progress has been made over the last two decades on understanding the components and mechanisms governing plant innate immunity. After detection of a pathogen, effective plant resistance depends on the activation of a complex signaling network integrated by small signaling molecules and hormonal pathways, and the balance of these hormone systems determines resistance to particular pathogens. The discovery of new components of hormonal signaling pathways, including plant nuclear hormone receptors, is providing a picture of complex crosstalk and induced hormonal changes that modulate disease and resistance through several protein families that perceive hormones within the nucleus and lead to massive gene induction responses often achieved by de-repression. This review highlights recent advances in our understanding of positive and negative regulators of these hormones signaling pathways that are crucial regulatory targets of hormonal crosstalk in disease and defense. We focus on the most recent discoveries on the jasmonate and salicylate pathway components that explain their crosstalk with other hormonal pathways in the nucleus. We discuss how these components fine-tune defense responses to build a robust plant immune system against a great number of different microbes and, finally, we summarize recent discoveries on specific nuclear hormonal manipulation by microbes which exemplify the ingenious ways by which pathogens can take control over the plant's hormone signaling network to promote disease.
在过去的二十年中，人们在理解植物先天免疫的组成部分和机制方面取得了非凡的进展。在检测到病原体后，有效的植物抗性取决于由小分子信号分子和激素途径整合的复杂信号网络的激活，并且这些激素系统的平衡决定了对特定病原体的抗性。激素信号通路新成分的发现，包括植物核激素受体，为复杂的串扰和诱导激素变化提供了一个图景，这些变化通过感知细胞核内激素的几个蛋白家族来调节疾病和抗性，并导致大量基因诱导反应，通常通过去抑制来实现。本文综述了我们对这些激素信号通路的正调节剂和负调节剂的理解的最新进展，这些调节剂是激素串扰在疾病和防御中的关键调控靶点。我们重点介绍了茉莉酸和水杨酸途径成分的最新发现，这些发现解释了它们在细胞核中与其他激素途径的串扰。我们讨论了这些成分如何微调防御反应，以建立一个强大的植物免疫系统来对抗大量不同的微生物，最后，我们总结了微生物对特定核激素的操纵的最新发现，这些发现说明了病原体可以控制植物激素信号网络以促进疾病的巧妙方式。
