关键词: 越橘, VcTTG1, 花青苷, 表达分析, 功能鉴定

Abstract: The objective of this study is to isolate a blueberry（Vaccinium corymbosum）cultivar ‘Duke’VcTTG1 gene encoding WD40 protein by PCR technology from transcriptome data and study its expression，to identify its function in anthocyanin biosynthesis. This study laid the foundation for further study of the molecular mechanism of VcTTG1 affecting anthocyanin biosynthesis in blueberry. Sequence analysis showed that the open reading frame（ORF）of VcTTG1（GenBank accession No. MH717246） is 1 044 bp，putatively encoded 348 amino acids. Protein structure analysis showed that VcTTG1 contained conserved WD40 domain. A phylogenetic tree indicated that the blueberry VcTTG1 exhibited the highestsequence similarity to Vitis vinifera VvWDR1. Expression analysis showed that VcTTG1 was expressed in roots，stems，young leaves，flowers and fruits. However，the expression levels varied，with the highest expression level in fruits and the relatively low transcript levels in stems. The content of anthocyanin in fruits was increased with the up-regulation of relative expression of VcTTG1. The VcTTG1 protein could interact with Arabidopsis bHLH protein AtTT8 and favorably contributes to anthocyanin accumulation in transgenic Arabidopsis. It is speculated that VcTTG1 plays a regulatory role in anthocyanin biosynthesis.

Key words: blueberry, VcTTG1, anthocyanin, expression analysis, functional identification