Characterization of Coptis japonica CjABCB2, an ATP-binding cassette protein involved in alkaloid transport

► Alkaloids often accumulate in a particular organ in plants. ► An ABC transporter CjABCB2 was isolated from Coptis japonica. ► CjABCB2 was localized to plasma membrane and took up alkaloids. ► Organ-specific expression of CjABCB2 was related to the alkaloid accumulation site. ► CjABCB2 was found to be involved in alkaloid translocation.