Transcriptome sequencing and anthocyanin metabolite analysis determines leaf color of Acer pseudo-sieboldianum in autumn

Abstract Background: Acer pseudo-sieboldianum is an often used color-leafed tree native to northeastern China, whose leaves are gorgeous in autumn and is used to great effect in landscaping. Leaf color is an important index affecting the ornamental traits of color-leafed plants. Thus, it is of great significance to study the mechanism in leaf coloring in Acer pseudo-sieboldianum as the development and application prospects of this research are broad, and further the utilization of local characteristics tree species with colored leaves. Results: In this study, the leaves of Acer pseudo-sieboldianum from three stages in the autumn color-changing period were used as materials. In order to investigate the related differentially expressed genes in the process of color transformation, we determined the anthocyanins in leaves and used high-throughput sequencing to analyze the associated transcriptomes. The results demonstrated that five anthocyanins were detected in this experiment. It is worth mentioning that Peonidin O-hexoside, Cyanidin 3-O-glucoside (Kuromanin) and Cyanidin 3,5-O-diglucoside (Cyanin) have significant differences in their content change in two of the tested periods, meaning these may be the key substances determining the final color of Acer pseudo-sieboldianum. A total of 67.47 Gb of clean data were obtained from our sequencing results. Functional annotation of unigenes, including comparison with COG and GO databases, yielded 35,316 unigene annotations. 16521 differentially expressed genes were identified from a statistical analysis of differentially gene expression. We were able to cluster genes related to leaf color formation in Acer pseudo-sieboldianum, including ANS, DFR, F3H, UFGT, and so on, based on the expression at specific times. Conclusions: This study enriched the available transcriptome information for Acer pseudo-sieboldianum and identified a series of differentially expressed genes related to leaf color, which provides valuable information for further study on the genetic mechanism of leaf color expression in Acer pseudo-sieboldianum.