The path from ?-carotene to carlactone, a strigolactone-like plant hormone.
16.03.2012
Alder A, Jamil M, Marzorati M, Bruno M, Vermathen M, Bigler P, Ghisla S, Bouwmeester H, Beyer P, Al-Babili S.
Science. 2012;335(6074):1348-51.
Strigolactones, phytohormones with diverse signaling activities, have a common structure consisting of two lactones connected by an enol-ether bridge. Strigolactones derive from carotenoids via a pathway involving the carotenoid cleavage dioxygenases 7 and 8 (CCD7 and CCD8) and the iron-binding protein D27. We show that D27 is a ?-carotene isomerase that converts all-trans-?-carotene into 9-cis-?-carotene, which is cleaved by CCD7 into a 9-cis-configured aldehyde. CCD8 incorporates three oxygens into 9-cis-?-apo-10'-carotenal and performs molecular rearrangement, linking carotenoids with strigolactones and producing carlactone, a compound with strigolactone-like biological activities. Knowledge of the structure of carlactone will be crucial for understanding the biology of strigolactones and may have applications in combating parasitic weeds.