Institute of Plant Biology, College of Life Science, National Taiwan University, Taipei, Taiwan.
Centre for Biological Sciences, University of Southampton, Southampton, UK Department of Biochemistry, Faculty of Pharmaceutical Sciences, Iwate Medical University, Iwate, Japan
J Exp Bot. 2014 Jun;65(11):2847-57. doi: 10.1093/jxb/eru230. Epub 2014 May 27.
The phytochrome family of red (R) and far-red (FR) light receptors (phyA-phyE in Arabidopsis) play important roles throughout plant development and regulate elongation growth during de-etiolation and under light. Phytochromes regulate growth through interaction with the phytohormones gibberellin, auxin, and brassinosteroid. Recently it has been established that jasmonic acid (JA), a phytohormone for stress responses, namely wounding and defence, is also important in inhibition of hypocotyl growth regulated by phyA and phyB. This review focuses on recent advances in our understanding of the molecular basis of the interaction between JA and phytochrome signalling particularly during seedling development in Arabidopsis. Significantly, JA biosynthesis genes are induced by phyA. The protein abundance of JAR1/FIN219, an enzyme for the final synthesis step to give JA-Ile, an active form of JA, is also determined by phyA. In addition, JAR1/FIN219 directly interacts with an E3-ligase, COP1, a master regulator for transcription factors regulating hypocotyl growth, suggesting a more direct role in growth regulation. There are a number of points of interaction in the molecular signalling of JA and phytochrome during seedling development in Arabidopsis, and we propose a model for how they work together to regulate hypocotyl growth.
植物光敏色素家族的红光（R）和远红光（FR）光受体（拟南芥中的 phyA-phyE）在植物发育过程中发挥着重要作用，并在脱黄化和光照下调节伸长生长。光敏色素通过与植物激素赤霉素、生长素和油菜素内酯的相互作用来调节生长。最近已经确定，茉莉酸（JA），一种应激反应的植物激素，即创伤和防御，在 phyA 和 phyB 调节的下胚轴生长抑制中也很重要。本综述重点介绍了我们对 JA 和光敏色素信号转导相互作用分子基础的最新认识，特别是在拟南芥幼苗发育过程中。值得注意的是，JA 生物合成基因受 phyA 诱导。JA-Ile 的最终合成步骤的酶 JAR1/FIN219 的蛋白丰度也受 phyA 决定，JA-Ile 是 JA 的一种活性形式。此外，JAR1/FIN219 直接与 E3 连接酶 COP1 相互作用，COP1 是调节下胚轴生长的转录因子的主要调节剂，这表明它在生长调节中具有更直接的作用。在拟南芥幼苗发育过程中，JA 和光敏色素的分子信号有多个相互作用点，我们提出了它们如何协同作用来调节下胚轴生长的模型。
