Carotenoids are isoprenoid compounds synthesized by all photosynthetic and some non‐photosynthetic organisms. They are essential for photosynthesis and contribute to many other aspects of a plant's life. The oxidative breakdown of carotenoids gives rise to the formation of a diverse family of essential metabolites called apocarotenoids. This metabolic process either takes place spontaneously through reactive oxygen species or is catalyzed by enzymes generally belonging to the CAROTENOID CLEAVAGE DIOXYGENASE family. Apocarotenoids include the phytohormones abscisic acid and strigolactones (SLs), signaling molecules and growth regulators. Abscisic acid and SLs are vital in regulating plant growth, development and stress response. SLs are also an essential component in plants’ rhizospheric communication with symbionts and parasites. Other apocarotenoid small molecules, such as blumenols, mycorradicins, zaxinone, anchorene, β‐cyclocitral, β‐cyclogeranic acid, β‐ionone and loliolide, are involved in plant growth and development, and/or contribute to different processes, including arbuscular mycorrhiza symbiosis, abiotic stress response, plant–plant and plant–herbivore interactions and plastid retrograde signaling. There are also indications for the presence of structurally unidentified linear cis‐carotene‐derived apocarotenoids, which are presumed to modulate plastid biogenesis and leaf morphology, among other developmental processes. Here, we provide an overview on the biology of old, recently discovered and supposed plant apocarotenoid signaling molecules, describing their biosynthesis, developmental and physiological functions, and role as a messenger in plant communication.

中文翻译：

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植物类胡萝卜素：从逆向信号传递到种间通讯

类胡萝卜素是由所有光合生物和一些非光合生物合成的类异戊二烯化合物。它们对于光合作用至关重要，并有助于植物生命的许多其他方面。类胡萝卜素的氧化分解导致形成称为“类胡萝卜素”的各种必需代谢产物家族。该代谢过程要么通过活性氧自然发生，要么由通常属于类胡萝卜素裂解二氧合酶家族的酶催化。类胡萝卜素包括植物激素脱落酸和松果内酯（SLs），信号分子和生长调节剂。脱落酸和SLs在调节植物生长，发育和胁迫反应中至关重要。SL也是植物与共生体和寄生虫进行根际交流的重要组成部分。其他的类胡萝卜素小分子，例如Blumenols，mycorradicins，zaxinone，anchoene，β-cyclocitral，β-cyclogeranicacid，β-ionone和loliolide，都参与植物的生长和发育，并且/或者促进了不同的过程，包括丛枝菌根共生，非生物胁迫响应，植物-植物和植物-草食动物的相互作用以及质体逆行信号。也有迹象表明存在结构上不确定的线性顺式-胡萝卜素衍生的类胡萝卜素被认为可调节质体生物发生和叶片形态以及其他发育过程。在这里，我们提供了关于旧的，最近发现的和假定的植物类胡萝卜素信号分子的生物学概述，描述了它们的生物合成，发育和生理功能，以及在植物交流中的信使作用。