Integrative Analysis of Metabolomic and Transcriptomic Data Reveals the Mechanism of Color Formation in Corms of .

(Thunb.) Breit. () is a very important plant that is commonly used in traditional Chinese medicine. Its corms can be used as medicine and function to alleviate cough, headache, and phlegm. The epidermis of corms is often light yellow to yellow in color; however, within the range of found in JingZhou City in Hubei Province, China, there is a form of in which the epidermis of the corm is red. We found that the total flavonoid content of red corms is significantly higher than that of yellow corms. The objective of this study was to understand the molecular mechanisms behind the difference in epidermal color between the two forms of . The results showed that a high content of anthocyanidin was responsible for the red epidermal color in , and 15 metabolites, including cyanidin-3-O-rutinoside-5-O-glucoside, cyanidin-3-O-glucoside, and cyanidin-3-O-rutinoside, were screened as potential color markers in through metabolomic analysis. Based on an analysis of the transcriptome, seven genes, including , , , , , , and , were found to have important effects on the biosynthesis of anthocyanins in the corm epidermis. Furthermore, two transcription factors (TFs), and , may have regulatory functions in the biosynthesis of anthocyanins in red corms. Using an integrative analysis of the metabolomic and transcriptomic data, we identified five genes, , , , , and , that may play important roles in the presence of the red epidermis color in corms.