Plant apocarotenoids: from retrograde signaling to interspecific communication

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