Objective   Liupao Tea (Camellia sinensis var. sinensis cv. Liupao) was studied for the genes associated with anthocyanin synthesis for target breeding.

  Methods   Anthocyanin were extracted with ethanol hydrochloride from Liupao Tea plants bearing purple or green buds. Transcriptome sequencing was performed using Illumina Hiseq 2500 high-throughput platform to identify differentially expressed genes, determine expression of the genes related to anthocyanin synthesis, and conduct GO and KEGG enrichment analyses on the extracts. The sequencing results were subsequently verified by fluorescence quantification PCR.

  Results   The young leaves on the tea plants borne with purple buds contained sevenfold higher anthocyanin than those on the plants with green buds. The transcriptome of the genes of the purple buds had 165570 unigenes with an average length of 1450 bp. Of them, 243 related to the anthocyanin biosynthesis pathway, and 43 significantly differentially expressed between the two types of plants. The 43 differentiated genes encoded 14 key enzymes, i.e., phenylalanine ammonia-lyase (PAL), chalcone synthase (CHS), chalcone isomerase (CHI), cinnamate acid 4-hydroxylase (C4H), anthocyanidin reductase (ANR), 4-coumarate-CoA ligase (4CL), acetyl-CoA carboxylase (ACC), flavonol synthase (FLS), flavonoid-3′,5′-hydroxylase (F3′5′H), flavonoid 3′-hydroxylase (F3′H), flavanone-3-hydroxylase (F3H), dihydroflavonol 4-reductase (DFR), anthocyanidin synthase (ANS), and leucoanthocyanidin reductase (LAR).

  Conclusion   Thirty-four genes significantly upregulated in Liupao Tea plants with purple buds were found to be associated with 14 key enzymes encoding anthocyanin biosynthesis. They were speculated to play an important role in the bud color differentiation between the two varieties.