Transcriptome Sequencing and Screening of Anthocyanin-Related Genes in the Leaves of Acer truncatum Bunge.

Acer truncatum Bunge is generally used as an ornamental tree because of its autumn leaves, although the viewing period is short-approximately 7-15 days. Color improvement of ornamental trees has consistently been an important research topic because color partially determines the value of the commodity; however, a lack of genomic data have limited the progress of molecular breeding research in this area. The purposes of this study were to obtain a transcriptome database for A. truncatum, screen anthocyanin biosynthesis-related genes, and reveal the mechanisms underlying leaf color transformation to provide a basis for increasing the viewing period or breeding cultivars that display red leaves throughout the growing season via gene regulation. In this study, although the use of an Illumina HiSeq 2000 platform and systematic bioinformatics analysis using both young and mature leaves as experimental materials, 233,912,882 clean reads were generated and 121,287 unique transcripts were retrieved. We selected 16 color-related genes (from the transcriptome results) for qRT-PCR to validate the results, and the expression trends of the selected genes were largely consistent with the transcriptome analysis results, with a consistency of 0.875. According to the results of the transcriptome analysis, the validation, and previous studies, we obtained sequences of genes related to anthocyanins, including CHS, CHI, ANS, UFGT, UGT75c1, DFR, BZ1, F3H, F3'H, LAR, ANR, FLS, and those of several transcription factors, including MYB1, BHLH, and WD40. Verifying specific regulation by one or several of these genes in the control of leaf color requires further research. The acquisition of transcriptomic information, especially information concerning anthocyanin biosynthesis-related genes and their base sequences, can provide a theoretical basis for the study of the molecular mechanisms determining changes in leaf color in Acer and is of great importance to the breeding of new cultivars.