Download MendeleyStructure of P-glycoprotein reveals a molecular basis for poly-specific drug binding.
Aller, S.G., Yu, J., Ward, A., Weng, Y., Chittaboina, S., Zhuo, R., Harrell, P.M., Trinh, Y.T., Zhang, Q., Urbatsch, I.L., Chang, G.(2009) Science 323: 1718-1722
- PubMed: 19325113
- DOI: https://doi.org/10.1126/science.1168750
- Primary Citation of Related Structures:
3G5U, 3G60, 3G61 - PubMed Abstract:
P-glycoprotein (P-gp) detoxifies cells by exporting hundreds of chemically unrelated toxins but has been implicated in multidrug resistance (MDR) in the treatment of cancers. Substrate promiscuity is a hallmark of P-gp activity, thus a structural description of poly-specific drug-binding is important for the rational design of anticancer drugs and MDR inhibitors. The x-ray structure of apo P-gp at 3.8 angstroms reveals an internal cavity of approximately 6000 angstroms cubed with a 30 angstrom separation of the two nucleotide-binding domains. Two additional P-gp structures with cyclic peptide inhibitors demonstrate distinct drug-binding sites in the internal cavity capable of stereoselectivity that is based on hydrophobic and aromatic interactions. Apo and drug-bound P-gp structures have portals open to the cytoplasm and the inner leaflet of the lipid bilayer for drug entry. The inward-facing conformation represents an initial stage of the transport cycle that is competent for drug binding.
Organizational Affiliation:
Department of Molecular Biology, Scripps Research Institute, 10550 North Torrey Pines Road, CB105, La Jolla, CA 92037, USA.
