MYBs affect the variation in the ratio of anthocyanin and flavanol in fruit peel and flesh in response to shade.
Fruit pigment accumulation, which represents an important indicator of nutrient quality and appearance value, is often affected by low light under rain, cloud, fog and haze conditions during the veraison period. It is not known whether continuous low light interferes with the production and accumulation of secondary metabolites in veraison fruit. In this paper, we measured pigments and the transcriptional level of genes related to secondary metabolites, i.e., flavonoid biosynthesis in the peel and flesh of Malus crabapple 'Radiant' fruit in response to normal light and shade from 10th July to 30th August. The results showed crosstalk between the flavonoid biosynthetic genes and the involvement of key transcription factors such as McMYB4, McMYB7, McMYB10, and McMYB16 in the regulation of the ratio of anthocyanins and flavanols, which accounted for the different colouration of the fruit peel and flesh under shade conditions. A model is proposed for the regulation of the flavonoid pathway in the peel and flesh of 'Radiant' fruit based on our study results. Moreover, the molecular mechanism for 'Radiant' fruit colouration provides reference information for understanding the light regulatory mechanism involved in the biosynthesis of flavonoids and for designing the next generation of apple breeding.
College of Plant Science and Technology, Beijing Key Laboratory for Agricultural Application and New Technique, Beijing Collaborative Innovation Center for Eco-environmental Improvement with Forestry and Fruit Trees, Beijing University of Agriculture, Beijing 102206, China.
Yanfen
Y
Lu
College of Plant Science and Technology, Beijing Key Laboratory for Agricultural Application and New Technique, Beijing Collaborative Innovation Center for Eco-environmental Improvement with Forestry and Fruit Trees, Beijing University of Agriculture, Beijing 102206, China.
Yufen
Y
Bu
College of Plant Science and Technology, Beijing Key Laboratory for Agricultural Application and New Technique, Beijing Collaborative Innovation Center for Eco-environmental Improvement with Forestry and Fruit Trees, Beijing University of Agriculture, Beijing 102206, China.
Suxiao
S
Hao
Department of Ornamental Horticulture, China Agricultural University, Beijing 100193,China.
Yaru
Y
Wang
College of Plant Science and Technology, Beijing Key Laboratory for Agricultural Application and New Technique, Beijing Collaborative Innovation Center for Eco-environmental Improvement with Forestry and Fruit Trees, Beijing University of Agriculture, Beijing 102206, China.
Jie
J
Zhang
College of Plant Science and Technology, Beijing Key Laboratory for Agricultural Application and New Technique, Beijing Collaborative Innovation Center for Eco-environmental Improvement with Forestry and Fruit Trees, Beijing University of Agriculture, Beijing 102206, China.
Ji
J
Tian
College of Plant Science and Technology, Beijing Key Laboratory for Agricultural Application and New Technique, Beijing Collaborative Innovation Center for Eco-environmental Improvement with Forestry and Fruit Trees, Beijing University of Agriculture, Beijing 102206, China. Electronic address: yaoyc_20@126.com.
Yuncong
Y
Yao
D000872:Anthocyanins / Q000096:biosynthesis*; D005419:Flavonoids / Q000096:biosynthesis* / Q000235:genetics; D005638:Fruit / Q000737:chemistry / Q000378:metabolism*; D005786:Gene Expression Regulation / Q000528:radiation effects; D008027:Light; D027845:Malus; D053858:Metabolic Networks and Pathways / Q000235:genetics / Q000528:radiation effects; D010858:Pigmentation / Q000235:genetics / Q000528:radiation effects; D014157:Transcription Factors / Q000502:physiology*
D000872:Anthocyanins; D005419:Flavonoids; D014157:Transcription Factors
Colouration; Flavonoids; Fruit; Malus sp.; Shade; ‘Radiant’