Genome-wide analysis of ATP-binding cassette transporters and their expression involved in anthocyanin accumulation in Blueberry ( <i>Vaccinium</i> spp.)

Blueberry ( Vaccinium spp.) is renowned for its high levels of antioxidant activities and anthocyanins, which provide significant health benefits. ATP binding cassette transporters (ABC proteins) are a highly expanded gene family crucial for plant development due to their role in translocating diverse substrates. Despite their importance, the identification and substrate classification of ABC proteins in blueberries, particularly those involved in anthocyanin transport, remain unexplored. In this study, we performed a genome - wide analysis of ABC genes in blueberries using bioinformatics analysis, including characterization of gene names, domain topologies, cis -elements, and phylogenetic analysis of subfamily members with ABC genes from other plants. Additionally, we used UPLC-DAD-ESI-MS analysis to measure the content and composition of anthocyanins across six developmental stages of the blueberry cultivar ‘Northland’ fruit. RNA expression profiles of VcABC genes were also analyzed. The results showed that a total of 613 VcABC genes were identified and divided into eight subfamilies. The promoter regions of these genes are rich in elements related to the phytohormones, light response, and stress. Gene structure and phylogenetic analysis indicated that VcABCC51 and VcABCC52 cluster with known anthocyanin transporters from other plants. Combing phylogenetic analysis with correlation analysis of expression patterns and anthocyanins accumulation, we identified five VcABCCs ( VcABCC34 , VcABCC29 , VcABCC51 , VcABCC69 and VcABCC71 ) as potential candidates involved in anthocyanin transport in blueberries.