Identification and differential expression analysis of ABC transporter gene from medicinal plant Dendrobium officinale / 药学学报

ABSTRACT

ABC transporters (ATP-binding cassette transporters) are a family of trans-membrane transport proteins, which are ubiquitous in prokaryotes and eukaryotes. They are functionallyinvolved in the transport and accumulation of plant secondary metabolites, phytohormone transport, lipid metabolism, exogenous toxins detoxification, plant disease and other aspects. Based on the genome and transcriptome data of Dendrobium officinale, 88ABC transporters were preliminarily identified in D. officinale and their functions and subcellular localization were predicted. These proteins are divided into seven subfamilies, ABCA-ABCI, including 4 ABCA, 19 ABCB, 12 ABCC, 3ABCD, 9 ABCF, 37ABCG and 4 ABCI, which are mainly located in plasma membrane, vacuole and Golgi apparatus. Comparative transcriptomic analysis of ABC protein expression profile between asymbiotic and symbiotic germination of D. officinale show that some members of ABCB and ABCG proteins are highly expressed during seed germination inoculated fungi. qPCR validated that 2 ABCB11 and 2 ABCG-PDR are significantly up-regulated in symbiotic assay compared to asymbiotic germination (fold change ≥ 10.0). These proteins are mainly involved in abscisic acid and auxin transport, suggesting that these proteins play an important role in the germination of D. officinale seed and in the interaction with microorganisms.