title: Cloning and Functional Characterization of the Maize (Zea mays L.) Carotenoid Epsilon Hydroxylase Gene.
abstract: The assignment of functions to genes in the carotenoid biosynthesis pathway is necessary to understand how the pathway is regulated and to obtain the basic information required for metabolic engineering. Few carotenoid ε-hydroxylases have been functionally characterized in plants although this would provide insight into the hydroxylation steps in the pathway. We therefore isolated mRNA from the endosperm of maize (Zea mays L., inbred line B73) and cloned a full-length cDNA encoding CYP97C19, a putative heme-containing carotenoid ε hydroxylase and member of the cytochrome P450 family. The corresponding CYP97C19 genomic locus on chromosome 1 was found to comprise a single-copy gene with nine introns. We expressed CYP97C19 cDNA under the control of the constitutive CaMV 35S promoter in the Arabidopsis thaliana lut1 knockout mutant, which lacks a functional CYP97C1 (LUT1) gene. The analysis of carotenoid levels and composition showed that lutein accumulated to high levels in the rosette leaves of the transgenic lines but not in the untransformed lut1 mutants. These results allowed the unambiguous functional annotation of maize CYP97C19 as an enzyme with strong zeinoxanthin ε-ring hydroxylation activity.
authors.affiliation: School of Life Sciences, Changchun Normal University, Changchun, 130032, China; School of Life Sciences, Beijing Normal University, Beijing, 100875, China.
authors.forename: Shu
authors.initials: S
authors.lastname: Chang
authors.affiliation: Departament de Producció Vegetal i Ciència Forestal, Universitat de Lleida-Agrotecnio Center, Lleida, 25198, Spain.
authors.forename: Judit
authors.initials: J
authors.lastname: Berman
authors.affiliation: School of Life Sciences, Changchun Normal University, Changchun, 130032, China.
authors.forename: Yanmin
authors.initials: Y
authors.lastname: Sheng
authors.affiliation: School of Life Sciences, Beijing Normal University, Beijing, 100875, China.
authors.forename: Yingdian
authors.initials: Y
authors.lastname: Wang
authors.affiliation: Departament de Producció Vegetal i Ciència Forestal, Universitat de Lleida-Agrotecnio Center, Lleida, 25198, Spain.
authors.forename: Teresa
authors.initials: T
authors.lastname: Capell
authors.affiliation: School of Life Sciences, Northeast Normal University, Changchun, 130024, China.
authors.forename: Lianxuan
authors.initials: L
authors.lastname: Shi
authors.affiliation: School of Life Sciences, Changchun Normal University, Changchun, 130032, China.
authors.forename: Xiuzhen
authors.initials: X
authors.lastname: Ni
authors.affiliation: Biosynthesis Group, Molecular Biosciences, Goethe University Frankfurt, D-60438, Frankfurt, Germany.
authors.forename: Gerhard
authors.initials: G
authors.lastname: Sandmann
authors.affiliation: Departament de Producció Vegetal i Ciència Forestal, Universitat de Lleida-Agrotecnio Center, Lleida, 25198, Spain; Institució Catalana de Recerca i Estudis Avancats, Barcelona, 08010, Spain.
authors.forename: Paul
authors.initials: P
authors.lastname: Christou
authors.affiliation: School of Life Sciences, Changchun Normal University, Changchun, 130032, China; Departament de Producció Vegetal i Ciència Forestal, Universitat de Lleida-Agrotecnio Center, Lleida, 25198, Spain.
authors.forename: Changfu
authors.initials: C
authors.lastname: Zhu
mesh_terms: D000595:Amino Acid Sequence; D017360:Arabidopsis / Q000235:genetics / Q000378:metabolism; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism; D002338:Carotenoids / Q000235:genetics* / Q000378:metabolism*; D003001:Cloning, Molecular / Q000379:methods; D003577:Cytochrome P-450 Enzyme System / Q000235:genetics / Q000378:metabolism; D018076:DNA, Complementary / Q000235:genetics; D056625:Endosperm / Q000235:genetics / Q000378:metabolism; D018506:Gene Expression Regulation, Plant / Q000235:genetics; D017343:Genes, Plant / Q000235:genetics; D014975:Lutein / Q000235:genetics / Q000378:metabolism; D006899:Mixed Function Oxygenases / Q000235:genetics* / Q000378:metabolism*; D018515:Plant Leaves / Q000235:genetics / Q000378:metabolism; D011401:Promoter Regions, Genetic / Q000235:genetics; D012333:RNA, Messenger / Q000235:genetics; D016415:Sequence Alignment; D003313:Zea mays / Q000235:genetics* / Q000378:metabolism*
chemical_list: D029681:Arabidopsis Proteins; D018076:DNA, Complementary; D012333:RNA, Messenger; D002338:Carotenoids; D003577:Cytochrome P-450 Enzyme System; D006899:Mixed Function Oxygenases; D014975:Lutein