6FN1

Zosuquidar and UIC2 Fab complex of human-mouse chimeric ABCB1 (ABCB1HM)


Experimental Data Snapshot

  • Method: ELECTRON MICROSCOPY
  • Resolution: 3.58 Å
  • Aggregation State: PARTICLE 
  • Reconstruction Method: SINGLE PARTICLE 

wwPDB Validation   3D Report Full Report


This is version 1.4 of the entry. See complete history


Literature

Structure of a zosuquidar and UIC2-bound human-mouse chimeric ABCB1.

Alam, A.Kung, R.Kowal, J.McLeod, R.A.Tremp, N.Broude, E.V.Roninson, I.B.Stahlberg, H.Locher, K.P.

(2018) Proc Natl Acad Sci U S A 115: E1973-E1982

  • DOI: https://doi.org/10.1073/pnas.1717044115
  • Primary Citation of Related Structures:  
    6FN1, 6FN4

  • PubMed Abstract: 

    The multidrug transporter ABCB1 (P-glycoprotein) is an ATP-binding cassette transporter that has a key role in protecting tissues from toxic insult and contributes to multidrug extrusion from cancer cells. Here, we report the near-atomic resolution cryo-EM structure of nucleotide-free ABCB1 trapped by an engineered disulfide cross-link between the nucleotide-binding domains (NBDs) and bound to the antigen-binding fragment of the human-specific inhibitory antibody UIC2 and to the third-generation ABCB1 inhibitor zosuquidar. Our structure reveals the transporter in an occluded conformation with a central, enclosed, inhibitor-binding pocket lined by residues from all transmembrane (TM) helices of ABCB1. The pocket spans almost the entire width of the lipid membrane and is occupied exclusively by two closely interacting zosuquidar molecules. The external, conformational epitope facilitating UIC2 binding is also visualized, providing a basis for its inhibition of substrate efflux. Additional cryo-EM structures suggest concerted movement of TM helices from both halves of the transporters associated with closing the NBD gap, as well as zosuquidar binding. Our results define distinct recognition interfaces of ABCB1 inhibitory agents, which may be exploited for therapeutic purposes.


  • Organizational Affiliation

    Institute of Molecular Biology and Biophysics, ETH Zürich, 8093 Zürich, Switzerland.


Macromolecules
Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 1
MoleculeChains Sequence LengthOrganismDetailsImage
Human-mouse chimeric ABCB1 (ABCBHM)1,249Homo sapiensMutation(s): 0 
Membrane Entity: Yes 
UniProt & NIH Common Fund Data Resources
Find proteins for P08183 (Homo sapiens)
Explore P08183 
Go to UniProtKB:  P08183
PHAROS:  P08183
GTEx:  ENSG00000085563 
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupP08183
Sequence Annotations
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  • Reference Sequence
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Entity ID: 2
MoleculeChains Sequence LengthOrganismDetailsImage
UIC2 Antigen Binding Fragment Light chain220Mus musculusMutation(s): 0 
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
Sequence Annotations
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  • Reference Sequence
Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 3
MoleculeChains Sequence LengthOrganismDetailsImage
UIC2 Antigen Binding Fragment Heavy Chain225Mus musculusMutation(s): 0 
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
Sequence Annotations
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  • Reference Sequence
Experimental Data & Validation

Experimental Data

  • Method: ELECTRON MICROSCOPY
  • Resolution: 3.58 Å
  • Aggregation State: PARTICLE 
  • Reconstruction Method: SINGLE PARTICLE 

Structure Validation

View Full Validation Report



Entry History & Funding Information

Deposition Data


Funding OrganizationLocationGrant Number
Swiss National Science FoundationSwitzerland--
European Molecular Biology OrganizationSwitzerland--
National Institutes of HealthUnited States--

Revision History  (Full details and data files)

  • Version 1.0: 2018-02-21
    Type: Initial release
  • Version 1.1: 2018-02-28
    Changes: Advisory, Author supporting evidence, Database references, Derived calculations
  • Version 1.2: 2018-03-07
    Changes: Database references
  • Version 1.3: 2019-12-11
    Changes: Other
  • Version 1.4: 2020-07-29
    Type: Remediation
    Reason: Carbohydrate remediation
    Changes: Data collection, Derived calculations, Structure summary