Download MendeleyMolecular structure of human P-glycoprotein in the ATP-bound, outward-facing conformation.
Kim, Y., Chen, J.(2018) Science 359: 915-919
- PubMed: 29371429
- DOI: https://doi.org/10.1126/science.aar7389
- Primary Citation of Related Structures:
6C0V - PubMed Abstract:
The multidrug transporter permeability (P)-glycoprotein is an adenosine triphosphate (ATP)-binding cassette exporter responsible for clinical resistance to chemotherapy. P-glycoprotein extrudes toxic molecules and drugs from cells through ATP-powered conformational changes. Despite decades of effort, only the structures of the inward-facing conformation of P-glycoprotein are available. Here we present the structure of human P-glycoprotein in the outward-facing conformation, determined by cryo-electron microscopy at 3.4-angstrom resolution. The two nucleotide-binding domains form a closed dimer occluding two ATP molecules. The drug-binding cavity observed in the inward-facing structures is reorientated toward the extracellular space and compressed to preclude substrate binding. This observation indicates that ATP binding, not hydrolysis, promotes substrate release. The structure evokes a model in which the dynamic nature of P-glycoprotein enables translocation of a large variety of substrates.
Organizational Affiliation:
Howard Hughes Medical Institute, The Rockefeller University, 1230 York Avenue, New York, NY 10065, USA.
