A macrocyclic peptide inhibitor traps MRP1 in a catalytically incompetent conformation

Proceedings of the National Academy of Sciences, Год журнала: 2023, Номер 120(11)

Опубликована: Март 9, 2023

Adenosine triphosphate-binding cassette (ABC) transporters, such as multidrug resistance protein 1 (MRP1), protect against cellular toxicity by exporting xenobiotic compounds across the plasma membrane. However, constitutive MRP1 function hinders drug delivery blood–brain barrier, and overexpression in certain cancers leads to acquired chemotherapy failure. Small-molecule inhibitors have potential block substrate transport, but few show specificity for MRP1. Here we identify a macrocyclic peptide, named CPI1, which inhibits with nanomolar potency shows minimal inhibition of related transporter P-glycoprotein. A cryoelectron microscopy (cryo-EM) structure at 3.27 Å resolution that CPI1 binds same location physiological leukotriene C4 (LTC 4 ). Residues interact both ligands contain large, flexible sidechains can form variety interactions, revealing how recognizes multiple structurally unrelated molecules. binding prevents conformational changes necessary adenosine triphosphate (ATP) hydrolysis suggesting it may therapeutic candidate.

Язык: Английский

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On the interplay between lipids and asymmetric dynamics of an NBS degenerate ABC transporter

Communications Biology, Год журнала: 2023, Номер 6(1)

Опубликована: Фев. 3, 2023

Abstract Multidrug resistance-associated proteins are ABC C-family exporters. They crucial in pharmacology as they transport various substrates across membranes. However, the role of degenerate nucleotide-binding site (NBS) remains unclear likewise interplay with surrounding lipid environment. Here, we propose a dynamic and structural overview MRP1 from ca . 110 μs molecular dynamics simulations. ATP binding to NBS1 is likely maintained along several cycles. Asymmetric NBD behaviour ensured by lower signal transduction NBD1 rest protein owing absence ball-and-socket conformation between coupling helices. Even though lipids play an active allosteric communication substrate-binding pocket NBDs, our results suggest that composition has limited impact, mostly affecting kinetics. We believe work can be extended other NBS provide hints for deciphering mechanistic differences among transporters.

Язык: Английский

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Structural and mechanistic basis of substrate transport by the multidrug transporter MRP4

Structure, Год журнала: 2023, Номер 31(11), С. 1407 - 1418.e6

Опубликована: Сен. 7, 2023

Multidrug resistance-associated protein 4 (MRP4) is an ATP-binding cassette (ABC) transporter expressed at multiple tissue barriers where it actively extrudes a wide variety of drug compounds. Overexpression MRP4 provides resistance to clinically used antineoplastic agents, making highly attractive therapeutic target for countering multidrug resistance. Here, we report cryo-EM structures physiologically relevant states lipid bilayer-embedded human MRP4, including complexes between and two widely chemotherapeutic agents complex its native substrate. The display clear similarities distinct differences in the coordination these chemically diverse substrates and, combination with functional mutational analysis, reveal molecular details transport mechanism. Our study key insights into unusually broad substrate specificity constitutes important contribution toward general understanding transporters.

Язык: Английский

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Structure of Ycf1p reveals the transmembrane domain TMD0 and the regulatory region of ABCC transporters

Proceedings of the National Academy of Sciences, Год журнала: 2021, Номер 118(21)

Опубликована: Май 21, 2021

Significance The Ycf1p structure provides an atomic model for the TMD0 domain of ABCC transporters and two segments regulatory (R) region that links NBD1 to TMD2. orientation in differs from seen SUR1, protein K ATP channels, demonstrating flexibility TMD0/ABC core contacts. suggests how posttranslational modifications R modulate ABC activity a mechanistic understanding several diseases occur due mutation human homologs Ycf1p.

Язык: Английский

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Amphipathic environments for determining the structure of membrane proteins by single-particle electron cryo-microscopy

Quarterly Reviews of Biophysics, Год журнала: 2021, Номер 54

Опубликована: Янв. 1, 2021

Over the past decade, structural biology of membrane proteins (MPs) has taken a new turn thanks to epoch-making technical progress in single-particle electron cryo-microscopy (cryo-EM) as well improvements sample preparation. The present analysis provides an overview extent and modes usage various types surfactants for cryo-EM studies. Digitonin, dodecylmaltoside, protein-based nanodiscs, lauryl maltoside-neopentyl glycol, glyco-diosgenin, amphipols (APols) are most popular at vitrification step. Surfactant exchange is frequently used between MP purification grid preparation, requiring extensive optimization each time study undertaken. variety both experimental approaches over few years bears witness need continue developing innovative optimizing conditions possibilities offered by novel APols EM applications discussed.

Язык: Английский

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