Transcriptome sequencing and metabolite analysis reveals the role of delphinidin metabolism in flower colour in grape hyacinth.
Grape hyacinth (Muscari) is an important ornamental bulbous plant with an extraordinary blue colour. Muscari armeniacum, whose flowers can be naturally white, provides an opportunity to unravel the complex metabolic networks underlying certain biochemical traits, especially colour. A blue flower cDNA library of M. armeniacum and a white flower library of M. armeniacum f. album were used for transcriptome sequencing. A total of 89 926 uni-transcripts were isolated, 143 of which could be identified as putative homologues of colour-related genes in other species. Based on a comprehensive analysis relating colour compounds to gene expression profiles, the mechanism of colour biosynthesis was studied in M. armeniacum. Furthermore, a new hypothesis explaining the lack of colour phenotype of the grape hyacinth flower is proposed. Alteration of the substrate competition between flavonol synthase (FLS) and dihydroflavonol 4-reductase (DFR) may lead to elimination of blue pigmentation while the multishunt from the limited flux in the cyanidin (Cy) synthesis pathway seems to be the most likely reason for the colour change in the white flowers of M. armeniacum. Moreover, mass sequence data obtained by the deep sequencing of M. armeniacum and its white variant provided a platform for future function and molecular biological research on M. armeniacum.
College of Horticulture, Northwest A & F University, Yangling 712100, Shaanxi, PR China Key Laboratory of Biology and Genetic Improvement of Horticultural Crops (Northwest Region), Ministry of Agriculture, Yangling, Shaanxi 712100, PR China State Key Laboratory of Crop Stress Biology in Arid Areas, Northwest A&F University, Yangling 712100, Shaanxi, PR China.
Qian
Q
Lou
Key Laboratory of Biology and Genetic Improvement of Horticultural Crops (Northwest Region), Ministry of Agriculture, Yangling, Shaanxi 712100, PR China State Key Laboratory of Crop Stress Biology in Arid Areas, Northwest A&F University, Yangling 712100, Shaanxi, PR China College of Forestry, Northwest A & F University, Yangling 712100, Shaanxi, PR China.
Yali
Y
Liu
College of Horticulture, Northwest A & F University, Yangling 712100, Shaanxi, PR China Key Laboratory of Biology and Genetic Improvement of Horticultural Crops (Northwest Region), Ministry of Agriculture, Yangling, Shaanxi 712100, PR China State Key Laboratory of Crop Stress Biology in Arid Areas, Northwest A&F University, Yangling 712100, Shaanxi, PR China.
Yinyan
Y
Qi
Key Laboratory of Biology and Genetic Improvement of Horticultural Crops (Northwest Region), Ministry of Agriculture, Yangling, Shaanxi 712100, PR China State Key Laboratory of Crop Stress Biology in Arid Areas, Northwest A&F University, Yangling 712100, Shaanxi, PR China College of Forestry, Northwest A & F University, Yangling 712100, Shaanxi, PR China.
Shuzhen
S
Jiao
Key Laboratory of Biology and Genetic Improvement of Horticultural Crops (Northwest Region), Ministry of Agriculture, Yangling, Shaanxi 712100, PR China State Key Laboratory of Crop Stress Biology in Arid Areas, Northwest A&F University, Yangling 712100, Shaanxi, PR China College of Forestry, Northwest A & F University, Yangling 712100, Shaanxi, PR China.
Feifei
F
Tian
Key Laboratory of Biology and Genetic Improvement of Horticultural Crops (Northwest Region), Ministry of Agriculture, Yangling, Shaanxi 712100, PR China State Key Laboratory of Crop Stress Biology in Arid Areas, Northwest A&F University, Yangling 712100, Shaanxi, PR China College of Forestry, Northwest A & F University, Yangling 712100, Shaanxi, PR China.
Ling
L
Jiang
College of Horticulture, Northwest A & F University, Yangling 712100, Shaanxi, PR China Key Laboratory of Biology and Genetic Improvement of Horticultural Crops (Northwest Region), Ministry of Agriculture, Yangling, Shaanxi 712100, PR China State Key Laboratory of Crop Stress Biology in Arid Areas, Northwest A&F University, Yangling 712100, Shaanxi, PR China wangyj@nwsuaf.edu.cn.
Yuejin
Y
Wang
D000872:Anthocyanins / Q000235:genetics / Q000378:metabolism*; D035264:Flowers / Q000235:genetics / Q000378:metabolism; D018506:Gene Expression Regulation, Plant; D019668:Liliaceae / Q000235:genetics / Q000378:metabolism; D010641:Phenotype; D010858:Pigmentation; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism*; D017423:Sequence Analysis, RNA; D059467:Transcriptome
D000872:Anthocyanins; D010940:Plant Proteins; C017185:delphinidin
Colour pigmentation; Muscari armeniacum; cyanidin; delphinidin; flower development; transcriptome analysis.