TY - JOUR

T1 - Structure of the human multidrug transporter ABCG2

AU - Taylor, Nicholas M I

AU - Manolaridis, Ioannis

AU - Jackson, Scott M

AU - Kowal, Julia

AU - Stahlberg, Henning

AU - Locher, Kaspar P

PY - 2017/6/22

Y1 - 2017/6/22

N2 - ABCG2 is a constitutively expressed ATP-binding cassette (ABC) transporter that protects many tissues against xenobiotic molecules. Its activity affects the pharmacokinetics of commonly used drugs and limits the delivery of therapeutics into tumour cells, thus contributing to multidrug resistance. Here we present the structure of human ABCG2 determined by cryo-electron microscopy, providing the first high-resolution insight into a human multidrug transporter. We visualize ABCG2 in complex with two antigen-binding fragments of the human-specific, inhibitory antibody 5D3 that recognizes extracellular loops of the transporter. We observe two cholesterol molecules bound in the multidrug-binding pocket that is located in a central, hydrophobic, inward-facing translocation pathway between the transmembrane domains. Combined with functional in vitro analyses, our results suggest a multidrug recognition and transport mechanism of ABCG2, rationalize disease-causing single nucleotide polymorphisms and the allosteric inhibition by the 5D3 antibody, and provide the structural basis of cholesterol recognition by other G-subfamily ABC transporters.

AB - ABCG2 is a constitutively expressed ATP-binding cassette (ABC) transporter that protects many tissues against xenobiotic molecules. Its activity affects the pharmacokinetics of commonly used drugs and limits the delivery of therapeutics into tumour cells, thus contributing to multidrug resistance. Here we present the structure of human ABCG2 determined by cryo-electron microscopy, providing the first high-resolution insight into a human multidrug transporter. We visualize ABCG2 in complex with two antigen-binding fragments of the human-specific, inhibitory antibody 5D3 that recognizes extracellular loops of the transporter. We observe two cholesterol molecules bound in the multidrug-binding pocket that is located in a central, hydrophobic, inward-facing translocation pathway between the transmembrane domains. Combined with functional in vitro analyses, our results suggest a multidrug recognition and transport mechanism of ABCG2, rationalize disease-causing single nucleotide polymorphisms and the allosteric inhibition by the 5D3 antibody, and provide the structural basis of cholesterol recognition by other G-subfamily ABC transporters.

KW - ATP Binding Cassette Transporter, Sub-Family G, Member 2/antagonists & inhibitors

KW - Adenosine Triphosphatases/chemistry

KW - Amino Acid Sequence

KW - Antibodies/chemistry

KW - Binding Sites

KW - Biological Transport

KW - Cholesterol/chemistry

KW - Cryoelectron Microscopy

KW - Humans

KW - Immunoglobulin Fab Fragments/chemistry

KW - Models, Molecular

KW - Neoplasm Proteins/antagonists & inhibitors

KW - Polymorphism, Single Nucleotide/genetics

KW - Protein Domains

U2 - 10.1038/nature22345

DO - 10.1038/nature22345

M3 - Journal article

C2 - 28554189

VL - 546

SP - 504

EP - 509

JO - Nature

JF - Nature

SN - 0028-0836

IS - 7659

ER -