title: Specific oxidative cleavage of carotenoids by VP14 of maize.
abstract: The plant growth regulator abscisic acid (ABA) is formed by the oxidative cleavage of an epoxy-carotenoid. The synthesis of other apocarotenoids, such as vitamin A in animals, may occur by a similar mechanism. In ABA biosynthesis, oxidative cleavage is the first committed reaction and is believed to be the key regulatory step. A new ABA-deficient mutant of maize has been identified and the corresponding gene, Vp14, has been cloned. The recombinant VP14 protein catalyzes the cleavage of 9-cis-epoxy-carotenoids to form C25 apo-aldehydes and xanthoxin, a precursor of ABA in higher plants.
authors.affiliation: Michigan State University-Department of Energy (MSU-DOE) Plant Research Laboratory, Michigan State University, East Lansing, MI 48824, USA.
authors.forename: S H
authors.initials: SH
authors.lastname: Schwartz
authors.forename: B C
authors.initials: BC
authors.lastname: Tan
authors.forename: D A
authors.initials: DA
authors.lastname: Gage
authors.forename: J A
authors.initials: JA
authors.lastname: Zeevaart
authors.forename: D R
authors.initials: DR
authors.lastname: McCarty
mesh_terms: D000040:Abscisic Acid / Q000096:biosynthesis; D002338:Carotenoids / Q000378:metabolism*; D002851:Chromatography, High Pressure Liquid; D049308:Dioxygenases; D009154:Mutation; D010084:Oxidation-Reduction; D010105:Oxygenases / Q000378:metabolism; D010940:Plant Proteins / Q000378:metabolism*; D011994:Recombinant Proteins / Q000378:metabolism; D013379:Substrate Specificity; D024341:Xanthophylls; D003313:Zea mays / Q000235:genetics / Q000378:metabolism*; D019207:beta Carotene / Q000031:analogs & derivatives* / Q000378:metabolism
chemical_list: D010940:Plant Proteins; D011994:Recombinant Proteins; D024341:Xanthophylls; D019207:beta Carotene; D002338:Carotenoids; C005613:violaxanthin; D000040:Abscisic Acid; D010105:Oxygenases; D049308:Dioxygenases; C069684:lignostilbene-alpha,beta-dioxygenase; C011947:neoxanthin