Abstract

The recent x-ray structure of mouse P-glycoprotein (Pgp) determined to 3.8 angstrom established the overall structural architecture of one of the most studied mammalian multidrug resistance (MDR) transporters. The structure of Pgp, however, is only a starting point for understanding its transport mechanism and potential inhibition. Clearly a higher resolution structure along with different conformations and co-crystal structures will be required to understand the detailed mechanism of transport coupled to ATP hydrolysis paving the way towards future rational drug design. We propose to (1) extend the resolution of Pgp crystals using very new membrane protein crystallization techniques and novel detergents to greatly improve the precision of the model, (2) determine additional conformations of Pgp both in the inward- and outward- facing conformations to map out the structural trajectories of the transport cycle, (3) determine the co-crystal structures of Pgp of two classical and clinically important compounds, doxorubicin and rhodamine, to understand poly-specific substrate binding, and (4) determine the x-ray structure of human Pgp or humanized version of Pgp, which will be very useful for drug design in the future.

Public Health Relevance

P-glycoprotein plays a significant role in drug efficacy and multidrug resistance to several diseases, including cancer and HIV. This high-impact project will provide a detailed molecular structural basis underlying its transport mechanism. The structures of Pgp should greatly facilitate the development of new drugs to circumvent multidrug resistance in the future.

  Funding Agency

Agency
National Institute of Health (NIH)
Institute
National Institute of General Medical Sciences (NIGMS)
Type
Research Project (R01)
Project #
5R01GM094367-02
Application #
8146078
Study Section
Biochemistry and Biophysics of Membranes Study Section (BBM)
Program Officer
Chin, Jean
Project Start
2010-09-20
Project End
2014-08-31
Budget Start
2011-09-01
Budget End
2012-08-31
Support Year
2
Fiscal Year
2011
Total Cost
$358,201
Indirect Cost

  Institution

Name
Scripps Research Institute
Department
Type
DUNS #
781613492
City
La Jolla
State
CA
Country
United States
Zip Code
92037

  Publications

Moeller, Arne; Lee, Sung Chang; Tao, Houchao et al. (2015) Distinct conformational spectrum of homologous multidrug ABC transporters. Structure 23:450-460
Harmsen, Stefan; Bedics, Matthew A; Wall, Matthew A et al. (2015) Rational design of a chalcogenopyrylium-based surface-enhanced resonance Raman scattering nanoprobe with attomolar sensitivity. Nat Commun 6:6570
Szewczyk, Paul; Tao, Houchao; McGrath, Aaron P et al. (2015) Snapshots of ligand entry, malleable binding and induced helical movement in P-glycoprotein. Acta Crystallogr D Biol Crystallogr 71:732-41
Hill, Jacqueline E; Linder, Michelle K; Davies, Kellie S et al. (2014) Selenorhodamine photosensitizers for photodynamic therapy of P-glycoprotein-expressing cancer cells. J Med Chem 57:8622-34
Martinez, Lorena; Arnaud, Ophélie; Henin, Emilie et al. (2014) Understanding polyspecificity within the substrate-binding cavity of the human multidrug resistance P-glycoprotein. FEBS J 281:673-82
Myette, Robert L; Conseil, Gwenaëlle; Ebert, Sean P et al. (2013) Chalcogenopyrylium dyes as differential modulators of organic anion transport by multidrug resistance protein 1 (MRP1), MRP2, and MRP4. Drug Metab Dispos 41:1231-9
Ward, Andrew B; Szewczyk, Paul; Grimard, Vinciane et al. (2013) Structures of P-glycoprotein reveal its conformational flexibility and an epitope on the nucleotide-binding domain. Proc Natl Acad Sci U S A 110:13386-91
Ebert, Sean P; Wetzel, Bryan; Myette, Robert L et al. (2012) Chalcogenopyrylium compounds as modulators of the ATP-binding cassette transporters P-glycoprotein (P-gp/ABCB1) and multidrug resistance protein 1 (MRP1/ABCC1). J Med Chem 55:4683-99
Loo, Tip W; Bartlett, M Claire; Detty, Michael R et al. (2012) The ATPase activity of the P-glycoprotein drug pump is highly activated when the N-terminal and central regions of the nucleotide-binding domains are linked closely together. J Biol Chem 287:26806-16
Orchard, Alexandra; Schamerhorn, Gregory A; Calitree, Brandon D et al. (2012) Thiorhodamines containing amide and thioamide functionality as inhibitors of the ATP-binding cassette drug transporter P-glycoprotein (ABCB1). Bioorg Med Chem 20:4290-302

Showing the most recent 10 out of 12 publications