Abstract
The ATP-binding cassette (ABC) transporter family is one of the largest and oldest protein families and encodes a class of transmembrane transporter proteins that transport substances in living organisms. Panax ginseng is a traditional Chinese herbal medicine, and its main active ingredient is ginsenoside, a secondary metabolite. Transportation and accumulation of secondary metabolites require the participation of ABC transporter proteins. In this study, we performed a genome-wide identification and expression analysis of the ginseng ABC transporter family using bioinformatics tools. Analysis of 106 PgABC genes showed that they were classified into seven subfamilies, among which ABCG was the most abundant subfamily. Chromosomal localization and covariance analyses showed that PgABC genes were unevenly distributed on chromosomes and that tandem repeat sequences existed. Tissue expression analyses revealed that PgABC expression was tissue-specific in ginseng. Cis-acting element analyses showed that PgABC genes responded to induction by hormones such as methyl jasmonate (MeJA). Subsequent qRT-PCR analysis of MeJA-treated ginseng adventitious roots revealed dynamic expression changes in nine PgABC genes, with PgABC14, PgABC18, and PgABC24-01 showing significant upregulation. The identification and analysis of the ABC transporter family in ginseng lays a theoretical foundation for the subsequent study of the function of the ABC gene family in ginseng and provides a theoretical basis for the study of ABC transporter proteins in other medicinal plant species.