National Natural Science Foundation of China (NSFC)
31971134
中国
引用
ジャーナル: Protein Sci / 年: 2020 タイトル: Cryo-electron microscopy structure of human ABCB6 transporter. 著者: Chunyu Wang / Can Cao / Nan Wang / Xiangxi Wang / Xianping Wang / Xuejun C Zhang / 要旨: Human ATP-binding cassette transporter 6 of subfamily B (ABCB6) is an ABC transporter involved in the translocation toxic metals and anti-cancer drugs. Using cryo-electron microscopy, we determined ...Human ATP-binding cassette transporter 6 of subfamily B (ABCB6) is an ABC transporter involved in the translocation toxic metals and anti-cancer drugs. Using cryo-electron microscopy, we determined the molecular structure of full-length ABCB6 in an apo state. The structure of ABCB6 unravels the architecture of a full-length ABCB transporter that harbors two N-terminal transmembrane domains which is indispensable for its ATPase activity in our in vitro assay. A slit-like substrate binding pocket of ABCB6 may accommodate the planar shape of porphyrins, and the existence of a secondary cavity near the mitochondrial intermembrane space side would further facilitate substrate release. Furthermore, the ATPase activity of ABCB6 stimulated with a variety of porphyrin substrates showed different profiles in the presence of glutathione (GSH), suggesting the action of a distinct substrate translocation mechanism depending on the use of GSH as a cofactor.