Hawkesbury Institute for the Environment, Western Sydney University, Locked Bag 1797, Penrith NSW, 2751, Australia.
Hawkesbury Institute for the Environment, Western Sydney University, Locked Bag 1797, Penrith NSW, 2751, Australia.
Arch Biochem Biophys. 2018 Sep 15;654:172-184. doi: 10.1016/j.abb.2018.07.014. Epub 2018 Jul 18.
Carotenoids are isoprenoid pigments synthesised by plants, algae, photosynthetic bacteria as well as some non-photosynthetic bacteria, fungi and insects. Abundant carotenoids found in nature are synthesised via a linear route from phytoene to lycopene after which the pathway bifurcates into cyclised α- and β-carotenes. Plants evolved additional steps to generate a diversity of cis-carotene intermediates, which can accumulate in fruits or tissues exposed to an extended period of darkness. Enzymatic or oxidative cleavage, light-mediated photoisomerization and histone modifications can affect cis-carotene accumulation. cis-carotene accumulation has been linked to the production of signaling metabolites that feedback and forward to regulate nuclear gene expression. When cis-carotenes accumulate, plastid biogenesis and operational control can become impaired. Carotenoid derived metabolites and phytohormones such as abscisic acid and strigolactones can fine-tune cellular homeostasis. There is a hunt to identify a novel cis-carotene derived apocarotenoid signal and to elucidate the molecular mechanism by which it facilitates communication between the plastid and nucleus. In this review, we describe the biosynthesis and evolution of cis-carotenes and their links to regulatory switches, as well as highlight how cis-carotene derived apocarotenoid signals might control organelle communication, physiological and developmental processes in response to environmental change.
类胡萝卜素是异戊二烯色素，由植物、藻类、光合细菌以及一些非光合细菌、真菌和昆虫合成。自然界中丰富的类胡萝卜素是通过从八氢番茄红素到番茄红素的线性途径合成的，然后该途径分叉成环化的α-和β-胡萝卜素。植物通过额外的步骤进化，产生了多种顺式类胡萝卜素中间体，这些中间体可以在果实或组织中积累，这些组织暴露在延长的黑暗期。酶或氧化裂解、光照介导的光异构化和组蛋白修饰可以影响顺式类胡萝卜素的积累。顺式类胡萝卜素的积累与信号代谢物的产生有关，这些代谢物可以反馈和向前调节核基因表达。当顺式类胡萝卜素积累时，质体生物发生和操作控制可能会受损。类胡萝卜素衍生的代谢物和植物激素，如脱落酸和独脚金内酯，可以微调细胞内稳态。人们正在寻找一种新的顺式类胡萝卜素衍生的开环类胡萝卜素信号，并阐明其分子机制，以促进质体和核之间的通讯。在这篇综述中，我们描述了顺式类胡萝卜素的生物合成和进化及其与调控开关的联系，并强调了顺式类胡萝卜素衍生的开环类胡萝卜素信号如何控制细胞器通讯、生理和发育过程以响应环境变化。
