Rothamsted Research, Harpenden, Hertfordshire AL5 2JQ, UK.
J Exp Biol. 2014 Jan 1;217(Pt 1):67-75. doi: 10.1242/jeb.089938.
Plant hormones are small molecules that regulate plant growth and development, as well as responses to changing environmental conditions. By modifying the production, distribution or signal transduction of these hormones, plants are able to regulate and coordinate both growth and/or stress tolerance to promote survival or escape from environmental stress. A central role for the gibberellin (GA) class of growth hormones in the response to abiotic stress is becoming increasingly evident. Reduction of GA levels and signalling has been shown to contribute to plant growth restriction on exposure to several stresses, including cold, salt and osmotic stress. Conversely, increased GA biosynthesis and signalling promote growth in plant escape responses to shading and submergence. In several cases, GA signalling has also been linked to stress tolerance. The transcriptional regulation of GA metabolism appears to be a major point of regulation of the GA pathway, while emerging evidence for interaction of the GA-signalling molecule DELLA with components of the signalling pathway for the stress hormone jasmonic acid suggests additional mechanisms by which GA signalling may integrate multiple hormone signalling pathways in the response to stress. Here, we review the evidence for the role of GA in these processes, and the regulation of the GA signalling pathway on exposure to abiotic stress. The potential mechanisms by which GA signalling modulates stress tolerance are also discussed.
植物激素是调节植物生长和发育以及对环境变化响应的小分子。通过改变这些激素的产生、分布或信号转导，植物能够调节和协调生长和/或应激耐受性，以促进生存或逃避环境应激。赤霉素（GA）类生长激素在非生物胁迫响应中的核心作用变得越来越明显。减少 GA 水平和信号传递已被证明有助于植物在暴露于几种胁迫下的生长限制，包括冷、盐和渗透胁迫。相反，增加 GA 生物合成和信号传递促进了植物对遮荫和淹没的逃避反应中的生长。在某些情况下，GA 信号也与应激耐受性有关。GA 代谢的转录调控似乎是 GA 途径调控的一个主要控制点，而 GA 信号分子 DELLA 与应激激素茉莉酸信号通路成分相互作用的新证据表明，GA 信号可能通过多种激素信号通路在应激响应中整合的其他机制。在这里，我们回顾了 GA 在这些过程中的作用的证据，以及 GA 信号通路在非生物胁迫下的调节。还讨论了 GA 信号调节应激耐受性的潜在机制。
