Role of core structural genes for flavonoid biosynthesis and transcriptional factors in flower color of plants

Abstract

Flower color is one of the most important qualitative characteristics of ornamental horticultural plants, which mainly depends on anthocyanins and carotenoids. Modification of flower color in ornamental plants involves many aspects, including complicated structural gens, transcription factors and metabolic pathways. Anthocyanins are important secondary metabolites in the flavonoid biosynthesis pathway, which mainly derive from six anthocyanidins. Anthocyanin has antioxidant activity, protects plants and performs some other functions. Studying the genes and regulatory factors in the biosynthesis pathway will contribute to cultivating novel flower color plants and to improving plants’ resistance. To date, a series of structural and regulatory genes that are involved in anthocyanin synthesis and color formation have been reported, whose functions have also been revealed. Some color-related transgenic flowers have been successfully obtained. Carotenoids are the source of the yellow pigments in the petals of many flowers. The carotenoid biosynthesis pathway as well as its major enzymes and genes are conducive to regulate its biosynthesis via genetic engineering methods and thereby changing the color of flowers. In this paper, we review the plant flower color in terms of mechanisms of plant pigment formation, classification of flower color, biosynthesis pathway, and genes related to anthocyanin formation. Subsequently, we analyze the regulating mechanism of the expression of these genes, including transcription regulation and post-transcription regulation. The methods and achievements in flower color improvement in recent years are summarized. Finally, analyzing the molecular regulatory network in flower color formation provides a theoretical basis for the improvement and modification of flower color.

Keywords:

• Flower color genes
• structural genes
• transcriptional factors
• flavonoid biosynthesis
• genetic engineering

Disclosure statement

No potential conflict of interest was reported by the authors.

Data availability

All data generated during the study are interpreted in the manuscript.

Additional information

Funding

This work was financially supported by the National Natural Science Foundation of China. (Grant No. 31572150).