Skip to main content

Thank you for visiting nature.com. You are using a browser version with limited support for CSS. To obtain the best experience, we recommend you use a more up to date browser (or turn off compatibility mode in Internet Explorer). In the meantime, to ensure continued support, we are displaying the site without styles and JavaScript.

  • Article
  • Published:

Structural basis of small-molecule inhibition of human multidrug transporter ABCG2

Abstract

ABCG2 is an ATP-binding cassette (ABC) transporter that protects tissues against xenobiotics, affects the pharmacokinetics of drugs and contributes to multidrug resistance. Although many inhibitors and modulators of ABCG2 have been developed, understanding their structure–activity relationship requires high-resolution structural insight. Here, we present cryo-EM structures of human ABCG2 bound to synthetic derivatives of the fumitremorgin C-related inhibitor Ko143 or the multidrug resistance modulator tariquidar. Both compounds are bound to the central, inward-facing cavity of ABCG2, blocking access for substrates and preventing conformational changes required for ATP hydrolysis. The high resolutions allowed for de novo building of the entire transporter and also revealed tightly bound phospholipids and cholesterol interacting with the lipid-exposed surface of the transmembrane domains (TMDs). Extensive chemical modifications of the Ko143 scaffold combined with in vitro functional analyses revealed the details of ABCG2 interactions with this compound family and provide a basis for the design of novel inhibitors and modulators.

This is a preview of subscription content, access via your institution

Access options

Buy this article

Prices may be subject to local taxes which are calculated during checkout

Fig. 1: Functional characteristics of Ko143 derivatives.
Fig. 2: Structure of the ABCG2–MZ29–Fab complex.
Fig. 3: ABCG2 NBDs.
Fig. 4: Structure of MB136-bound ABCG2 revealing a central multidrug-binding site.
Fig. 5: ABCG2–lipid interactions.
Fig. 6: Proposed mechanism of inhibition.

Similar content being viewed by others

References

  1. Crowley, E., McDevitt, C. A. & Callaghan, R. Generating inhibitors of P-glycoprotein: where to, now? Methods Mol. Biol. 596, 405–432 (2010).

    Article  CAS  PubMed  Google Scholar 

  2. Diestra, J. E. et al. Frequent expression of the multi-drug resistance-associated protein BCRP/MXR/ABCP/ABCG2 in human tumours detected by the BXP-21 monoclonal antibody in paraffin-embedded material. J. Pathol. 198, 213–219 (2002).

    Article  CAS  PubMed  Google Scholar 

  3. Fetsch, P. A. et al. Localization of the ABCG2 mitoxantrone resistance-associated protein in normal tissues. Cancer Lett. 235, 84–92 (2006).

    Article  CAS  PubMed  Google Scholar 

  4. Robey, R. W. et al. ABCG2: a perspective. Adv. Drug Deliv. Rev. 61, 3–13 (2009).

    Article  CAS  PubMed  Google Scholar 

  5. Ishikawa, T., Aw, W. & Kaneko, K. Metabolic interactions of purine derivatives with human ABC transporter ABCG2: genetic testing to assess gout risk. Pharmaceuticals (Basel) 6, 1347–1360 (2013).

    Article  Google Scholar 

  6. Gillet, J. P. & Gottesman, M. M. Advances in the molecular detection of ABC transporters involved in multidrug resistance in cancer. Curr. Pharm. Biotechnol. 12, 686–692 (2011).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  7. Gottesman, M. M., Fojo, T. & Bates, S. E. Multidrug resistance in cancer: role of ATP-dependent transporters. Nat. Rev. Cancer 2, 48–58 (2002).

    Article  CAS  PubMed  Google Scholar 

  8. Iorio, A. L. et al. Blood-brain barrier and breast cancer resistance protein: a limit to the therapy of CNS tumors and neurodegenerative diseases. Anticancer. Agents Med. Chem. 16, 810–815 (2016).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  9. Sarkadi, B., Homolya, L., Szakács, G. & Váradi, A. Human multidrug resistance ABCB and ABCG transporters: participation in a chemoimmunity defense system. Physiol. Rev. 86, 1179–1236 (2006).

    Article  CAS  PubMed  Google Scholar 

  10. Sharom, F. J. The P-glycoprotein multidrug transporter. Essays Biochem. 50, 161–178 (2011).

    Article  CAS  PubMed  Google Scholar 

  11. Bakhsheshian, J. et al. Overlapping substrate and inhibitor specificity of human and murine ABCG2. Drug Metab. Dispos. 41, 1805–1812 (2013).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  12. Imai, Y. et al. Breast cancer resistance protein exports sulfated estrogens but not free estrogens. Mol. Pharmacol. 64, 610–618 (2003).

    Article  CAS  PubMed  Google Scholar 

  13. Mao, Q. & Unadkat, J. D. Role of the breast cancer resistance protein (BCRP/ABCG2) in drug transport–an update. AAPS J. 17, 65–82 (2015).

    Article  CAS  PubMed  Google Scholar 

  14. Mo, W. & Zhang, J. T. Human ABCG2: structure, function, and its role in multidrug resistance. Int. J. Biochem. Mol. Biol. 3, 1–27 (2012).

    CAS  PubMed  Google Scholar 

  15. Vlaming, M. L., Lagas, J. S. & Schinkel, A. H. Physiological and pharmacological roles of ABCG2 (BCRP): recent findings in Abcg2 knockout mice. Adv. Drug Deliv. Rev. 61, 14–25 (2009).

    Article  CAS  PubMed  Google Scholar 

  16. Allen, J. D. et al. Potent and specific inhibition of the breast cancer resistance protein multidrug transporter in vitro and in mouse intestine by a novel analogue of fumitremorgin C. Mol. Cancer Ther. 1, 417–425 (2002).

    Article  CAS  PubMed  Google Scholar 

  17. Holland, M. L., Lau, D. T., Allen, J. D. & Arnold, J. C. The multidrug transporter ABCG2 (BCRP) is inhibited by plant-derived cannabinoids. Br. J. Pharmacol. 152, 815–824 (2007).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  18. Kannan, P. et al. The “specific” P-glycoprotein inhibitor Tariquidar is also a substrate and an inhibitor for breast cancer resistance protein (BCRP/ABCG2). ACS Chem. Neurosci. 2, 82–89 (2011).

    Article  CAS  PubMed  Google Scholar 

  19. Peterson, B. G., Tan, K. W., Osa-Andrews, B. & Iram, S. H. High-content screening of clinically tested anticancer drugs identifies novel inhibitors of human MRP1 (ABCC1). Pharmacol. Res. 119, 313–326 (2017).

    Article  CAS  PubMed  Google Scholar 

  20. Puentes, C. O. et al. Solid phase synthesis of tariquidar-related modulators of ABC transporters preferring breast cancer resistance protein (ABCG2). Bioorg. Med. Chem. Lett. 21, 3654–3657 (2011).

    Article  CAS  PubMed  Google Scholar 

  21. Rabindran, S. K. et al. Reversal of a novel multidrug resistance mechanism in human colon carcinoma cells by fumitremorgin C. Cancer Res. 58, 5850–5858 (1998).

    CAS  PubMed  Google Scholar 

  22. Rabindran, S. K., Ross, D. D., Doyle, L. A., Yang, W. & Greenberger, L. M. Fumitremorgin C reverses multidrug resistance in cells transfected with the breast cancer resistance protein. Cancer Res. 60, 47–50 (2000).

    CAS  PubMed  Google Scholar 

  23. Weidner, L. D. et al. The inhibitor Ko143 is not specific for ABCG2. J. Pharmacol. Exp. Ther. 354, 384–393 (2015).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  24. Bauer, S. et al. Quinoline carboxamide-type ABCG2 modulators: indole and quinoline moieties as anilide replacements. ChemMedChem 8, 1773–1778 (2013).

    Article  CAS  PubMed  Google Scholar 

  25. Köhler, S. C. & Wiese, M. HM30181 derivatives as novel potent and selective inhibitors of the breast cancer resistance protein (BCRP/ABCG2). J. Med. Chem. 58, 3910–3921 (2015).

    Article  PubMed  Google Scholar 

  26. Ochoa-Puentes, C. et al. Benzanilide-biphenyl replacement: a bioisosteric approach to quinoline carboxamide-type ABCG2 modulators. ACS Med. Chem. Lett. 4, 393–396 (2013).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  27. Pick, A., Klinkhammer, W. & Wiese, M. Specific inhibitors of the breast cancer resistance protein (BCRP). ChemMedChem 5, 1498–1505 (2010).

    Article  CAS  PubMed  Google Scholar 

  28. Roe, M. et al. Reversal of P-glycoprotein mediated multidrug resistance by novel anthranilamide derivatives. Bioorg. Med. Chem. Lett. 9, 595–600 (1999).

    Article  CAS  PubMed  Google Scholar 

  29. Taylor, N. M. I. et al. Structure of the human multidrug transporter ABCG2. Nature 546, 504–509 (2017).

    CAS  PubMed  Google Scholar 

  30. Haider, A. J. et al. Identification of residues in ABCG2 affecting protein trafficking and drug transport, using co-evolutionary analysis of ABCG sequences. Biosci. Rep. 35, e00241 (2015).

    Article  PubMed  PubMed Central  Google Scholar 

  31. László, L., Sarkadi, B. & Hegedűs, T. Jump into a new fold-A homology based model for the ABCG2/BCRP multidrug transporter. PLoS One 11, e0164426 (2016).

    Article  PubMed  PubMed Central  Google Scholar 

  32. Ni, Z., Bikadi, Z., Cai, X., Rosenberg, M. F. & Mao, Q. Transmembrane helices 1 and 6 of the human breast cancer resistance protein (BCRP/ABCG2): identification of polar residues important for drug transport. Am. J. Physiol. Cell Physiol. 299, C1100–C1109 (2010).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  33. Ni, Z. et al. Identification of proline residues in or near the transmembrane helices of the human breast cancer resistance protein (BCRP/ABCG2) that are important for transport activity and substrate specificity. Biochemistry 50, 8057–8066 (2011).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  34. Khunweeraphong, N., Stockner, T. & Kuchler, K. The structure of the human ABC transporter ABCG2 reveals a novel mechanism for drug extrusion. Sci. Rep. 7, 13767 (2017).

    Article  PubMed  PubMed Central  Google Scholar 

  35. van Loevezijn, A., Allen, J. D., Schinkel, A. H. & Koomen, G. J. Inhibition of BCRP-mediated drug efflux by fumitremorgin-type indolyl diketopiperazines. Bioorg. Med. Chem. Lett. 11, 29–32 (2001).

    Article  PubMed  Google Scholar 

  36. Zhou, S. et al. The ABC transporter Bcrp1/ABCG2 is expressed in a wide variety of stem cells and is a molecular determinant of the side-population phenotype. Nat. Med. 7, 1028–1034 (2001).

    Article  CAS  PubMed  Google Scholar 

  37. Aller, S. G. et al. Structure of P-glycoprotein reveals a molecular basis for poly-specific drug binding. Science 323, 1718–1722 (2009).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  38. Johnson, Z. L. & Chen, J. Structural basis of substrate recognition by the multidrug resistance protein MRP1. Cell 168, 1075–1085.e9 (2017).

    Article  CAS  PubMed  Google Scholar 

  39. Gergely, S. et al. in Drug Resistance in Cancer Cells (eds Siddik, Z. & Mehta, K.) 1–20 (Springer, New York, 2009).

  40. Kühnle, M. et al. Potent and selective inhibitors of breast cancer resistance protein (ABCG2) derived from the p-glycoprotein (ABCB1) modulator tariquidar. J. Med. Chem. 52, 1190–1197 (2009).

    Article  PubMed  Google Scholar 

  41. Storch, C. H., Ehehalt, R., Haefeli, W. E. & Weiss, J. Localization of the human breast cancer resistance protein (BCRP/ABCG2) in lipid rafts/caveolae and modulation of its activity by cholesterol in vitro. J. Pharmacol. Exp. Ther. 323, 257–264 (2007).

    Article  CAS  PubMed  Google Scholar 

  42. Szilagyi, J. T., Vetrano, A. M., Laskin, J. D. & Aleksunes, L. M. Localization of the placental BCRP/ABCG2 transporter to lipid rafts: Role for cholesterol in mediating efflux activity. Placenta 55, 29–36 (2017).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  43. Lee, J. Y. et al. Crystal structure of the human sterol transporter ABCG5/ABCG8. Nature 533, 561–564 (2016).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  44. Telbisz, Á., Hegedüs, C., Váradi, A., Sarkadi, B. & Özvegy-Laczka, C. Regulation of the function of the human ABCG2 multidrug transporter by cholesterol and bile acids: effects of mutations in potential substrate and steroid binding sites. Drug Metab. Dispos. 42, 575–585 (2014).

    Article  PubMed  PubMed Central  Google Scholar 

  45. Velamakanni, S., Janvilisri, T., Shahi, S. & van Veen, H. W. A functional steroid-binding element in an ATP-binding cassette multidrug transporter. Mol. Pharmacol. 73, 12–17 (2008).

    Article  CAS  PubMed  Google Scholar 

  46. Macalou, S. et al. The linker region of breast cancer resistance protein ABCG2 is critical for coupling of ATP-dependent drug transport. Cell. Mol. Life Sci. 73, 1927–1937 (2016).

    Article  CAS  PubMed  Google Scholar 

  47. Basseville, A. & Bates, S. E. Gout, genetics and ABC transporters. F1000 Biol. Rep. 3, 23 (2011).

    Article  PubMed  PubMed Central  Google Scholar 

  48. Furukawa, T. et al. Major SNP (Q141K) variant of human ABC transporter ABCG2 undergoes lysosomal and proteasomal degradations. Pharm. Res. 26, 469–479 (2009).

    Article  CAS  PubMed  Google Scholar 

  49. Liu, Y., Yang, Y., Qi, J., Peng, H. & Zhang, J. T. Effect of cysteine mutagenesis on the function and disulfide bond formation of human ABCG2. J. Pharmacol. Exp. Ther. 326, 33–40 (2008).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  50. Ni, Z., Bikadi, Z., Rosenberg, M. F. & Mao, Q. Structure and function of the human breast cancer resistance protein (BCRP/ABCG2). Curr. Drug Metab. 11, 603–617 (2010).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  51. Suzuki, M., Suzuki, H., Sugimoto, Y. & Sugiyama, Y. ABCG2 transports sulfated conjugates of steroids and xenobiotics. J. Biol. Chem. 278, 22644–22649 (2003).

    Article  CAS  PubMed  Google Scholar 

  52. Geisse, S., Jordan, M. & Wurm, F. M. Large-scale transient expression of therapeutic proteins in mammalian cells. Methods Mol. Biol. 308, 87–98 (2005).

    CAS  PubMed  Google Scholar 

  53. Ritchie, T. K. et al. Chapter 11 - Reconstitution of membrane proteins in phospholipid bilayer nanodiscs. Methods Enzymol. 464, 211–231 (2009).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  54. Geertsma, E. R., Nik Mahmood, N. A., Schuurman-Wolters, G. K. & Poolman, B. Membrane reconstitution of ABC transporters and assays of translocator function. Nat. Protoc. 3, 256–266 (2008).

    Article  CAS  PubMed  Google Scholar 

  55. Schaffner, W. & Weissmann, C. A rapid, sensitive, and specific method for the determination of protein in dilute solution. Anal. Biochem. 56, 502–514 (1973).

    Article  CAS  PubMed  Google Scholar 

  56. Chifflet, S., Torriglia, A., Chiesa, R. & Tolosa, S. A method for the determination of inorganic phosphate in the presence of labile organic phosphate and high concentrations of protein: application to lens ATPases. Anal. Biochem. 168, 1–4 (1988).

    Article  CAS  PubMed  Google Scholar 

  57. Wienken, C. J., Baaske, P., Rothbauer, U., Braun, D. & Duhr, S. Protein-binding assays in biological liquids using microscale thermophoresis. Nat. Commun. 1, 100 (2010).

    Article  PubMed  Google Scholar 

  58. Zheng, S. Q. et al. MotionCor2: anisotropic correction of beam-induced motion for improved cryo-electron microscopy. Nat. Methods 14, 331–332 (2017).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  59. Zhang, K. Gctf: Real-time CTF determination and correction. J. Struct. Biol. 193, 1–12 (2016).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  60. Kimanius, D., Forsberg, B. O., Scheres, S. H. & Lindahl, E. Accelerated cryo-EM structure determination with parallelisation using GPUs in RELION-2. eLife 5, e18722 (2016).

    Article  PubMed  PubMed Central  Google Scholar 

  61. Punjani, A., Rubinstein, J. L., Fleet, D. J. & Brubaker, M. A. cryoSPARC: algorithms for rapid unsupervised cryo-EM structure determination. Nat. Methods 14, 290–296 (2017).

    Article  CAS  PubMed  Google Scholar 

  62. Rosenthal, P. B. & Henderson, R. Optimal determination of particle orientation, absolute hand, and contrast loss in single-particle electron cryomicroscopy. J. Mol. Biol. 333, 721–745 (2003).

    Article  CAS  PubMed  Google Scholar 

  63. Kucukelbir, A., Sigworth, F. J. & Tagare, H. D. Quantifying the local resolution of cryo-EM density maps. Nat. Methods 11, 63–65 (2014).

    Article  CAS  PubMed  Google Scholar 

  64. Emsley, P., Lohkamp, B., Scott, W. G. & Cowtan, K. Features and development of Coot. Acta Crystallogr. D Biol. Crystallogr. 66, 486–501 (2010).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  65. Moriarty, N. W., Grosse-Kunstleve, R. W. & Adams, P. D. electronic Ligand Builder and Optimization Workbench (eLBOW): a tool for ligand coordinate and restraint generation. Acta Crystallogr. D Biol. Crystallogr. 65, 1074–1080 (2009).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  66. Adams, P. D. et al. PHENIX: a comprehensive Python-based system for macromolecular structure solution. Acta Crystallogr. D Biol. Crystallogr. 66, 213–221 (2010).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  67. Chen, V. B. et al. MolProbity: all-atom structure validation for macromolecular crystallography. Acta Crystallogr. D Biol. Crystallogr. 66, 12–21 (2010).

    Article  CAS  PubMed  Google Scholar 

Download references

Acknowledgements

This research was supported by the Swiss National Science Foundation through the National Centre of Competence in Research (NCCR) TransCure and by a Swiss Federal Institute of Technology Zurich (ETH Zurich) research grant ETH-22-14-1. J.K. was also supported by the TransCure Young Investigator Award. N.M.I.T. was also supported by the University of Basel Research Fund for Junior Investigators. Cryo-EM data for the ABCG2–MZ29–Fab and ABCG2–MB136–Fab samples were collected at the electron microscopy facility at ETH Zurich (ScopeM); we thank P. Tittmann for technical support. Cryo-EM data for the ABCG2-MZ29 sample were collected at C-CINA, University of Basel; we thank K. Goldie, L. Kováčik and A. Fecteau-Lefebvre for technical support. We also thank J. Bloch for helpful discussions, F. Antoni, M. Scholler and D. Wifling (University of Regensburg) for technical assistance and helpful discussions and B. Sorrentino (St. Jude Children’s Research Hospital) for providing the 5D3-producing hybridoma cell line.

Author information

Authors and Affiliations

Authors

Contributions

I.M. expressed and purified ABCG2 and 5D3-Fab. I.M. and S.M.J. performed MST and thermostability experiments. S.M.J. reconstituted ABCG2 into liposomes and lipidic nanodiscs. J.K. prepared all cryo-grids and collected cryo-EM data for ABCG2–MZ29–Fab and ABCG2–MB136–Fab. I.M. and J.K. determined the structure of ABCG2–MZ29–Fab. J.K. determined the structure of ABCG2–MB136–Fab. N.M.I.T. and H.S. collected cryo-EM data and determined the structure of ABCG2–MZ29. I.M. and K.P.L. refined and validated the structures with the help of J.K. and N.M.I.T. M.Z. synthesized Ko143 and derivatives, and R.B. synthesized FKo143 and FKo132, under the supervision of K.-H.A. M.B. synthesized MB136. M.B., S.B., G.B., B.K. and A.B. designed MB136 and supervised and assisted in its synthesis. S.M.J. screened the compounds and performed all of the ATPase and transport assays. K.P.L., K.-H.A., S.M.J. and I.M. conceived the project. K.P.L., S.M.J. and I.M. planned the experiments. S.M.J., I.M. and K.P.L. wrote the manuscript; all authors contributed to revisions.

Corresponding authors

Correspondence to Karl-Heinz Altmann or Kaspar P. Locher.

Ethics declarations

Competing interests

The authors declare no competing interests.

Additional information

Publisher’s note: Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Integrated supplementary information

Supplementary Figure 1 Purification of ABCG2, SEC-TS and reconstitution of ABCG2–MZ29–Fab into nanodiscs.

a, Preparative SEC profile of detergent-purified ABCG2. The fraction used for SEC-TS and nanodisc preparation is indicated with an arrow. b, SEC-TS of ABCG2 before or after the addition of specified inhibitors at 10 µM concentration and E1S at 50 µM concentration. c, Preparative SEC profile of the nanodisc-reconstituted ABCG2-MZ29-Fab complex. The fraction used for cryo-EM grid preparation and SDS-PAGE analysis is indicated by ‘1’. d, Non-reducing SDS-PAGE of the nanodisc-reconstituted ABCG2-MZ29-Fab complex shown in c.

Source data

Supplementary Figure 2 Cryo-EM map generation and data processing flow chart of the ABCG2–MZ29–Fab complex.

a, An example micrograph (drift-corrected, dose-weighted, and low-pass filtered to 20 Å) of the nanodisc-reconstituted ABCG2–MZ29-Fab data set. White scale bar, 50 nm. b, Averages of 15 representative two-dimensional class averages of the final round of two-dimensional classification, sorted in decreasing order by the number of particles assigned to each class. c, The flow chart for the cryo-EM data processing and structure determination of the ABCG2-MZ29-Fab complex.

Supplementary Figure 3 Atomic model refinement and local resolution of the ABCG2–MZ29–Fab complex.

a, FSC from the RELION auto-refine procedure of the unmasked half-maps (blue), the random-phase corrected half-maps (brown), the half-maps after masking (cyan), and the half-maps after masking and correction for the influence of the mask (pink). A horizontal line (blue) is drawn for the FSC = 0.143 criterion. For both the unmasked and the corrected FSC curves, their intersection with the FSC = 0.143 line is indicated by an arrow, and the resolution at this point is indicated. b, FSC curve of the final 3.1 Å refined model versus the map it was refined against (FSCfull, black line). FSC curve of the final model with introduced shifts (mean value of 0.3 Å) refined against the first of two independent half-maps (half-map 1) (to which it was refined against; FSCwork red line) or the same refined model versus the second independent half-map (to which is was not refined; FSChalf2, green line). c, Full view of the RELION local-resolution-filtered map of ABCG2-MZ29-Fab colored by local resolution as calculated by ResMap with the clipping plane in the middle of the molecule. ABCG2, Fab and nanodiscs are labeled. d, Resolution distribution histogram generated in ResMap. e, Angular distribution plot for the final reconstruction.

Supplementary Figure 4 Fit of the model to the density of the ABCG2–MZ29–Fab complex.

a, Fit of the TM helices of the final model of the ABCG2 TMD to the post-processed and masked map from RELION. A region of up to 2 Å around the atoms is shown. b, Same as a but showing the intramolecular disulfide (C592-C608), the intermolecular disulfide (C603-C603’) and N596 decorated with two GlcNAcs. c, Same as a but showing the Walker A motif with selected residues numbered. d, Same as a but showing the Walker B motif and the D loop. e, Same as a but showing the α-helix containing Q141 with selected residues numbered. f, Same as a but showing the fit of MZ29 and surrounding residues.

Supplementary Figure 5 Cryo-EM map generation and data processing flow chart of the ABCG2–MB136–Fab complex.

a, An example micrograph (drift-corrected, dose-weighted, and low-pass filtered to 20 Å) of the nanodisc-reconstituted ABCG2–MB136-Fab data set. White scale bar, 50 nm. b, Averages of 15 representative two-dimensional class averages of the final round of two-dimensional classification, sorted in decreasing order by the number of particles assigned to each class. c, The flow chart for the cryo-EM data processing and structure determination of the ABCG2-MB136-Fab complex.

Supplementary Figure 6 Atomic model refinement and local resolution of the ABCG2–MB136–Fab complex.

a, FSC from the RELION auto-refine procedure of the unmasked half-maps (blue), the random-phase corrected half-maps (brown), the half-maps after masking (cyan), and the half-maps after masking and correction for the influence of the mask (pink). A horizontal line (blue) is drawn for the FSC = 0.143 criterion. For both the unmasked and the corrected FSC curves, their intersection with the FSC = 0.143 line is indicated by an arrow, and the resolution at this point is indicated. b, Angular distribution plot for the final reconstruction. c, Full view of the RELION local-resolution-filtered map of ABCG2-MB136-Fab colored by local resolution as calculated by ResMap with the clipping plane in the middle of the molecule. ABCG2, Fab and nanodiscs are labeled. d, Resolution distribution histogram generated in ResMap. e, Fit of one MB136 molecule into the EM density of the ABCG2-MB136-Fab structure processed with C2 symmetry. f, Fit of one MB136 molecule into the EM density of the ABCG2-MB136-Fab structure processed with C1 symmetry.

Supplementary Figure 7 Cryo-EM map generation and data processing flow chart of the ABCG2–MZ29 complex.

a, An example micrograph (drift-corrected, dose-weighted, and low-pass filtered to 20 Å) of the nanodisc-reconstituted ABCG2–MZ29 data set. White scale bar, 50 nm. b, Averages of 15 representative two-dimensional class averages of the final round of two-dimensional classification, sorted in decreasing order by the number of particles assigned to each class. c, The flow chart for the cryo-EM data processing and structure determination of the ABCG2-MZ29 complex.

Supplementary Figure 8 Atomic model refinement and local resolution of the ABCG2–MZ29 complex.

a, FSC from the RELION auto-refine procedure of the unmasked half-maps (blue), the random-phase corrected half-maps (brown), the half-maps after masking (cyan), and the half-maps after masking and correction for the influence of the mask (pink). A horizontal line (blue) is drawn for the FSC = 0.143 criterion. For both the unmasked and the corrected FSC curves, their intersection with the FSC = 0.143 line is indicated by an arrow, and the resolution at this point is indicated. b, FSC curve of the final 3.56 Å refined model versus the map it was refined against (FSCfull, black line). FSC curve of the final model with introduced shifts (mean value of 0.3 Å) refined against the first of two independent half-maps (half-map1) (to which it was refined against; FSCwork red line) or the same refined model versus the second independent half-map (to which is was not refined; FSChalf2, green line). c, Full view of the RELION local resolution filtered map of ABCG2-MZ29 colored by local resolution as calculated by ResMap with the clipping plane in the middle of the molecule. d, Resolution distribution histogram generated in ResMap. e, Angular distribution plot for the final reconstruction. f, Superposition of the ABCG2-MZ29-Fab structure with the Fabs removed (blue) and the ABCG2-MZ29 structure (red). The insert shows the superposition of the bound MZ29 molecules.

Supplementary information

Supplementary Text and Figures

Supplementary Figures 1–8, Supplementary Tables 1–5 and Supplementary Note

Life Sciences Reporting Summary

Supplementary Dataset 1

Combined source data for Figs. 1a–c, 4b and 6a and Supplementary Fig. 1b

Rights and permissions

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Jackson, S.M., Manolaridis, I., Kowal, J. et al. Structural basis of small-molecule inhibition of human multidrug transporter ABCG2. Nat Struct Mol Biol 25, 333–340 (2018). https://doi.org/10.1038/s41594-018-0049-1

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1038/s41594-018-0049-1

This article is cited by

Search

Quick links

Nature Briefing: Translational Research

Sign up for the Nature Briefing: Translational Research newsletter — top stories in biotechnology, drug discovery and pharma.

Get what matters in translational research, free to your inbox weekly. Sign up for Nature Briefing: Translational Research