title: High temperature reduces apple fruit colour via modulation of the anthocyanin regulatory complex.
abstract: The biosynthesis of anthocyanin in many plants is affected by environmental conditions. In apple (Malus × domestica Borkh.), concentrations of fruit anthocyanins are lower under hot climatic conditions. We examined the anthocyanin accumulation in the peel of maturing 'Mondial Gala' and 'Royal Gala' apples, grown in both temperate and hot climates, and using artificial heating of on-tree fruit. Heat caused a dramatic reduction of both peel anthocyanin concentration and transcripts of the genes of the anthocyanin biosynthetic pathway. Heating fruit rapidly reduced expression of the R2R3 MYB transcription factor (MYB10) responsible for coordinative regulation for red skin colour, as well as expression of other genes in the transcriptional activation complex. A single night of low temperatures is sufficient to elicit a large increase in transcription of MYB10 and consequently the biosynthetic pathway. Candidate genes that can repress anthocyanin biosynthesis did not appear to be responsible for reductions in anthocyanin content. We propose that temperature-induced regulation of anthocyanin biosynthesis is primarily caused by altered transcript levels of the activating anthocyanin regulatory complex.
authors.affiliation: The New Zealand Institute for Plant & Food Research Limited (Plant & Food Research) Private Bag, Auckland.
authors.forename: Kui
authors.initials: K
authors.lastname: Lin-Wang
authors.forename: Diego
authors.initials: D
authors.lastname: Micheletti
authors.forename: John
authors.initials: J
authors.lastname: Palmer
authors.forename: Richard
authors.initials: R
authors.lastname: Volz
authors.forename: Lidia
authors.initials: L
authors.lastname: Lozano
authors.forename: Richard
authors.initials: R
authors.lastname: Espley
authors.forename: Roger P
authors.initials: RP
authors.lastname: Hellens
authors.forename: David
authors.initials: D
authors.lastname: Chagnè
authors.forename: Daryl D
authors.initials: DD
authors.lastname: Rowan
authors.forename: Michela
authors.initials: M
authors.lastname: Troggio
authors.forename: Ignasi
authors.initials: I
authors.lastname: Iglesias
authors.forename: Andrew C
authors.initials: AC
authors.lastname: Allan
mesh_terms: D000217:Acyltransferases / Q000235:genetics / Q000378:metabolism; D000872:Anthocyanins / Q000096:biosynthesis*; D002980:Climate; D003001:Cloning, Molecular; D015536:Down-Regulation; D005638:Fruit / Q000502:physiology*; D018506:Gene Expression Regulation, Plant; D017343:Genes, Plant; D006358:Hot Temperature; D027845:Malus / Q000235:genetics / Q000502:physiology*; D010802:Phylogeny; D010858:Pigmentation; D011401:Promoter Regions, Genetic; D014026:Nicotiana / Q000235:genetics / Q000502:physiology; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism*; D015533:Transcriptional Activation
chemical_list: D000872:Anthocyanins; D014157:Transcription Factors; D000217:Acyltransferases; C020141:flavanone synthetase