title: Identification and characterisation of F3GT1 and F3GGT1, two glycosyltransferases responsible for anthocyanin biosynthesis in red-fleshed kiwifruit (Actinidia chinensis).
abstract: Much of the diversity of anthocyanins is due to the action of glycosyltransferases, which add sugar moieties to anthocyanidins. We identified two glycosyltransferases, F3GT1 and F3GGT1, from red-fleshed kiwifruit (Actinidia chinensis) that perform sequential glycosylation steps. Red-fleshed genotypes of kiwifruit accumulate anthocyanins mainly in the form of cyanidin 3-O-xylo-galactoside. Genes in the anthocyanin and flavonoid biosynthetic pathway were identified and shown to be expressed in fruit tissue. However, only the expression of the glycosyltransferase F3GT1 was correlated with anthocyanin accumulation in red tissues. Recombinant enzyme assays in vitro and in vivo RNA interference (RNAi) demonstrated the role of F3GT1 in the production of cyanidin 3-O-galactoside. F3GGT1 was shown to further glycosylate the sugar moiety of the anthocyanins. This second glycosylation can affect the solubility and stability of the pigments and modify their colour. We show that recombinant F3GGT1 can catalyse the addition of UDP-xylose to cyanidin 3-galactoside. While F3GGT1 is responsible for the end-product of the pathway, F3GT1 is likely to be the key enzyme regulating the accumulation of anthocyanin in red-fleshed kiwifruit varieties.
authors.affiliation: The New Zealand Institute for Plant and Food Research Ltd, Private Bag 92 169, Auckland, New ZealandSchool of Biological Sciences, University of Auckland, Private Bag 92019, Auckland, New ZealandThe New Zealand Institute for Plant and Food Research Ltd, East Street 3214, Hamilton, New Zealand.
authors.forename: Mirco
authors.initials: M
authors.lastname: Montefiori
authors.affiliation: The New Zealand Institute for Plant and Food Research Ltd, Private Bag 92 169, Auckland, New ZealandSchool of Biological Sciences, University of Auckland, Private Bag 92019, Auckland, New ZealandThe New Zealand Institute for Plant and Food Research Ltd, East Street 3214, Hamilton, New Zealand.
authors.forename: Richard V
authors.initials: RV
authors.lastname: Espley
authors.affiliation: The New Zealand Institute for Plant and Food Research Ltd, Private Bag 92 169, Auckland, New ZealandSchool of Biological Sciences, University of Auckland, Private Bag 92019, Auckland, New ZealandThe New Zealand Institute for Plant and Food Research Ltd, East Street 3214, Hamilton, New Zealand.
authors.forename: David
authors.initials: D
authors.lastname: Stevenson
authors.affiliation: The New Zealand Institute for Plant and Food Research Ltd, Private Bag 92 169, Auckland, New ZealandSchool of Biological Sciences, University of Auckland, Private Bag 92019, Auckland, New ZealandThe New Zealand Institute for Plant and Food Research Ltd, East Street 3214, Hamilton, New Zealand.
authors.forename: Janine
authors.initials: J
authors.lastname: Cooney
authors.affiliation: The New Zealand Institute for Plant and Food Research Ltd, Private Bag 92 169, Auckland, New ZealandSchool of Biological Sciences, University of Auckland, Private Bag 92019, Auckland, New ZealandThe New Zealand Institute for Plant and Food Research Ltd, East Street 3214, Hamilton, New Zealand.
authors.forename: Paul M
authors.initials: PM
authors.lastname: Datson
authors.affiliation: The New Zealand Institute for Plant and Food Research Ltd, Private Bag 92 169, Auckland, New ZealandSchool of Biological Sciences, University of Auckland, Private Bag 92019, Auckland, New ZealandThe New Zealand Institute for Plant and Food Research Ltd, East Street 3214, Hamilton, New Zealand.
authors.forename: Anna
authors.initials: A
authors.lastname: Saiz
authors.affiliation: The New Zealand Institute for Plant and Food Research Ltd, Private Bag 92 169, Auckland, New ZealandSchool of Biological Sciences, University of Auckland, Private Bag 92019, Auckland, New ZealandThe New Zealand Institute for Plant and Food Research Ltd, East Street 3214, Hamilton, New Zealand.
authors.forename: Ross G
authors.initials: RG
authors.lastname: Atkinson
authors.affiliation: The New Zealand Institute for Plant and Food Research Ltd, Private Bag 92 169, Auckland, New ZealandSchool of Biological Sciences, University of Auckland, Private Bag 92019, Auckland, New ZealandThe New Zealand Institute for Plant and Food Research Ltd, East Street 3214, Hamilton, New Zealand.
authors.forename: Roger P
authors.initials: RP
authors.lastname: Hellens
authors.affiliation: The New Zealand Institute for Plant and Food Research Ltd, Private Bag 92 169, Auckland, New ZealandSchool of Biological Sciences, University of Auckland, Private Bag 92019, Auckland, New ZealandThe New Zealand Institute for Plant and Food Research Ltd, East Street 3214, Hamilton, New Zealand.
authors.forename: Andrew C
authors.initials: AC
authors.lastname: Allan
mesh_terms: D029042:Actinidia / Q000201:enzymology* / Q000235:genetics / Q000378:metabolism*; D000872:Anthocyanins / Q000096:biosynthesis*; D018506:Gene Expression Regulation, Plant; D016695:Glycosyltransferases / Q000235:genetics / Q000378:metabolism*; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism*
chemical_list: D000872:Anthocyanins; D010940:Plant Proteins; D016695:Glycosyltransferases