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Updated: Jul 11, 2026

ABCG5/G8 Crystallization in a Lipidic Bicelle Environment for X-Ray Crystallography
Published on: August 25, 2023
The sterol transporting heterodimer ABCG5/ABCG8 requires bile salts to mediate cholesterol efflux
Carlos Vrins1, Edwin Vink, Kristin E Vandenberghe
1Academic Medical Center, Department of Medical Biochemistry, Meibergdreef 15, 1105 AZ Amsterdam, The Netherlands.
Abstract:
The ATP binding cassette transporters ABCG5 and ABCG8 are indispensable for hepatobiliary cholesterol transport. In this study, we investigated the specificity of the heterodimer for cholesterol acceptors. Dog gallbladder epithelial cells were mono- or double-transfected with lentiviral mouse Abcg5 and Abcg8 vectors. Double-transfected cells showed increased efflux to different bile salt (BS) species, while mono-transfected cells did not show enhanced efflux. The efflux was initiated at micellar concentrations and addition of phosphatidylcholine increased efflux. Cholesterol secretion was highly BS dependent, whereas other cholesterol acceptors such as ApoAI, HDL or methyl-beta-cyclodextrin did not elicit Abcg5/g8 dependent cholesterol secretion.
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