Genetic Analysis of bHLH Family in Purple Lettuce (Lactuca sativa L.)

The bHLH family is one of the largest transcription factor families in organisms, which widely participates in various important activities during growth and development by involving many physiological and biochemical pathways, such as regulating secondary metabolism. Purple lettuce is popular for being rich in anthocyanin and other secondary metabolites which are beneficial for health. Studies in model plants showed that bHLH genes are important for the anthocyanin synthesis pathway. Now preliminary reports about the anthocyanin accumulation in purple lettuce have been made by many research teams. However, the studies in the genetic mechanism of anthocyanin biosynthesis metabolism were few, and the bHLH gene family in purple lettuce has not been characterized. Based on the genetic database of purple lettuce, we carried out the bioinformatic analysis of the bHLH gene family in purple lettuce, including analyzing the potential purple lettuce bHLH transcription factors, predicting the molecular weight, isoelectric point, the subcellular localization, and the phylogeny tree of LsbHLH family referring to AtbHLH gene family by using an online software analysis tool based on machine learning algorithms. Results suggested that Unigene 13011_All, a member of the LsbHLH gene family, plays an important role in anthocyanin synthesis. It is the first time to systematically characterize the bHLH gene family in purple lettuce. These data not only laid a foundation for further study of anthocyanin metabolism but also provided useful information for relevant research.