Genome-Wide Analysis of ATP Binding Cassette (ABC) Transporters in Peach (Prunus persica) and Identification of a Gene PpABCC1 Involved in Anthocyanin Accumulation

Abstract

The ATP-binding cassette (ABC) transporter family is a large and diverse protein superfamily that plays various roles in plant growth and development. Although the ABC transporters are known to aid in the transport of a wide range of substrates across biological membranes, their role in anthocyanin transport remains elusive. In this study, we identified a total of 132 putative <i>ABC</i> genes in the peach genome, and they were phylogenetically classified into eight subfamilies. Variations in spatial and temporal gene expression levels resulted in differential expression patterns of <i>PpABC</i> family members in various tissues of peach. <i>PpABCC1</i> was identified as the most likely candidate gene essential for anthocyanin accumulation in peach. Transient overexpression of <i>PpABCC1</i> caused a significant increase in anthocyanin accumulation in tobacco leaves and peach fruit, whereas virus-induced gene silencing of <i>PpABCC1</i> in the blood-fleshed peach resulted in a significant decrease in anthocyanin accumulation. The <i>PpABCC1</i> promoter contained an MYB binding <i>cis</i>-element, and it could be activated by anthocyanin-activator PpMYB10.1 based on yeast one-hybrid and dual luciferase assays. Thus, it seems that <i>PpABCC1</i> plays a crucial role in anthocyanin accumulation in peach. Our results provide a new insight into the vacuolar transport of anthocyanins in peach.