Recent Advances on the Molecular Mechanisms of Anthocyanin Synthesis in Fruits

Anthocyanins are important natural water-soluble, health-promoting pigments that have much effect on the quality of fruits. The anthocyanin biosynthetic pathway in fruits is clear. Anthocyanin accumulation depends on coordinated expression of structural genes encoding anthocyanin biosynthesis. Structural gene expression is regulated by regulatory genes, including MYB, basic helix-loop-helix(b HLH), and WD40 classes. The structural genes and the key regulatory genes controlling the pathway have been isolated in many fruits. Here we reviewed the recent advances in molecular mechanisms of regulatory genes in anthocyanin biosynthesis, including classes, concentration and functions of anthocyanins, transcriptional regulation of the anthocyanin biosynthesis, micro RNAs regulation, as well as the internal and external infl uences on anthocyanin biosynthesis in fruits. Especially, we pointed many gaps remain in the regulatory network of MYB, b HLH and WD40 transcription factors. Furthermore, new discoveries have begun to reveal links between the internal infl uences(plant hormones, genetics, maturity, biological clock, etc.), external environmental infl uences(light, temperature, p H, nutrition, etc.) and the regulatory genes in anthocyanin biosynthesis during fruit ripening. These reserches favor the anthocyanin biosynthesis of fruits at the molecular level from the point of view of interaction between the regulatory networks.