The altered activity of the fructose transporter GLUT5, an isoform of the facilitated-diffusion glucose transporter family, has been linked to disorders such as type 2 diabetes and obesity. GLUT5 is also overexpressed in certain tumour cells, and inhibitors are potential drugs for these conditions. Here we describe the crystal structures of GLUT5 from Rattus norvegicus and Bos taurus in open outward- and open inward-facing conformations, respectively. GLUT5 has a major facilitator superfamily fold like other homologous monosaccharide transporters. On the basis of a comparison of the inward-facing structures of GLUT5 and human GLUT1, a ubiquitous glucose transporter, we show that a single point mutation is enough to switch the substrate-binding preference of GLUT5 from fructose to glucose. A comparison of the substrate-free structures of GLUT5 with occluded substrate-bound structures of Escherichia coli XylE suggests that, in addition to global rocker-switch-like re-orientation of the bundles, local asymmetric rearrangements of carboxy-terminal transmembrane bundle helices TM7 and TM10 underlie a ‘gated-pore’ transport mechanism in such monosaccharide transporters.

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Primary accessions

Data deposits

The coordinates and the structure factors for bovine and rat GLUT5 have been deposited in the Protein Data Bank under accessions 4YB9 and 4YBQ, respectively.


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We are grateful to D. Slotboom, A. Cameron and S. Newstead for discussions and comments, and J. Mansfield for assistance with large-scale yeast fermentations and H. Unno with rGLUT5 crystallization. Data were collected at the European Synchrotron Radiation Facility, Diamond Light Source, and SPring-8 (proposal numbers 2011A1393, 2011B1229, 2012A1184, 2012B1253, 2013A1241, 2013B1237, 2014A1348 and 2014B1407), with assistance from beamline scientists. This work was funded by the Knut and Alice Wallenberg Foundation (D.D), The Royal Society through the University Research Fellow scheme (D.D), the BBSRC (BB/G02325/1 to S.I.), the ERATO Human Receptor Crystallography Project of the Japan Science and Technology Agency (JST) (S.I.), by the Research Acceleration Program of the JST (S.I.), by the Targeted Proteins Research Program of the Ministry of Education, Culture, Sports, Science and Technology (MEXT) of Japan (S.I.), and by Grants-in-Aids for Scientific Research from the MEXT (No. 22570114 to N.N.), and by the Platform for Drug Discovery, Informatics, and Structural Life Science from the MEXT (T.K.). The authors are grateful for the use of the Membrane Protein Laboratory funded by the Wellcome Trust (grant 062164/Z/00/Z) at the Diamond Light Source Limited, and The Centre for Biomembrane Research (CBR), supported by the Swedish Foundation for Strategic Research. H.J.K. was a recipient of a Human Frontiers Postdoctoral fellowship and D.D. acknowledges support from EMBO through the Young Investigator Program (YIP).

Author information

Author notes

    • Norimichi Nomura
    • , Grégory Verdon
    •  & Hae Joo Kang

    These authors contributed equally to this work.


  1. Department of Cell Biology, Graduate School of Medicine, Kyoto University, Konoe-cho, Yoshida, Sakyo-ku, Kyoto 606-8501, Japan

    • Norimichi Nomura
    • , Tatsuro Shimamura
    • , Yayoi Nomura
    • , Yumi Sato
    • , Hitomi Abe
    • , Yoshiko Nakada-Nakura
    • , Tomoya Hino
    • , Takatoshi Arakawa
    • , Takeshi Murata
    • , Takuya Kobayashi
    •  & So Iwata
  2. Japan Science and Technology Agency, ERATO, Iwata Human Receptor Crystallography Project, Yoshida-Konoe-cho, Sakyo-ku, Kyoto 606-8501, Japan

    • Norimichi Nomura
    • , Tatsuro Shimamura
    • , Yayoi Nomura
    • , Tomoya Hino
    • , Takatoshi Arakawa
    • , Takeshi Murata
    • , Takuya Kobayashi
    •  & So Iwata
  3. Japan Science and Technology Agency, Research Acceleration Program, Membrane Protein Crystallography Project, Yoshida-Konoe-cho, Sakyo-ku, Kyoto 606-8501, Japan

    • Norimichi Nomura
    • , Tatsuro Shimamura
    • , Yayoi Nomura
    • , Yumi Sato
    • , Yoshiko Nakada-Nakura
    • , Takeshi Murata
    • , Takuya Kobayashi
    •  & So Iwata
  4. Division of Molecular Biosciences, Imperial College London, London SW7 2AZ, UK

    • Grégory Verdon
    • , Hae Joo Kang
    • , Yo Sonoda
    • , So Iwata
    •  & David Drew
  5. Membrane Protein Laboratory, Diamond Light Source, Harwell Science and Innovation Campus, Didcot, Chilton, Oxfordshire OX11 0DE, UK

    • Grégory Verdon
    • , Hae Joo Kang
    •  & So Iwata
  6. Research Complex at Harwell, Rutherford Appleton Laboratory, Harwell, Oxford, Didcot, Oxfordshire OX11 0FA, UK

    • Grégory Verdon
    • , Hae Joo Kang
    •  & So Iwata
  7. Centre for Biomembrane Research, Department of Biochemistry and Biophysics, Stockholm University, SE-106 91 Stockholm, Sweden

    • Saba Abdul Hussien
    • , Aziz Abdul Qureshi
    • , Mathieu Coincon
    •  & David Drew
  8. Department of Quantitative Biology and Medicine, Research Center for Advanced Science and Technology, University of Tokyo, 4-6-1 Komaba, Meguro-ku, Tokyo 153-8904, Japan

    • Osamu Kusano-Arai
    • , Hiroko Iwanari
    •  & Takao Hamakubo
  9. Systems and Structural Biology Center, RIKEN, 1-7-22 Suehiro-cho, Tsurumi-ku, Yokohama 230-0045, Japan

    • Takeshi Murata
    •  & So Iwata
  10. Laboratory of Biophysics, School of Medicine, Teikyo University, Hachioji, Tokyo 192-0395, Japan

    • Michihiro Kasahara


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N.N., S.I. and D.D. designed the project. Cloning, expression screening and initial crystallization of rat and bovine GLUT5 was carried out by H.J.K., Y.So. and D.D. Crystal optimization of bovine GLUT5 was carried out by H.J.K. and G.V. Data collection, structure determination and refinement of bovine GLUT5 was carried out by G.V. Generation of rat GLUT5 scFv fragment was carried out by N.N., Y.N., T.M., Y.N.-N., O.K.-A., H.I., T.A., T.K. and T.Ha. Expression and purification of the Fv fragment was carried out by N.N., Y.N., Y.Sa., H.A. and T.Hi. Co-crystallization of rat GLUT5–Fv complex and data collection was performed by N.N. and Y.N. with assistance from T.Hi. and S.I. Structure determination and refinement of rat GLUT5–Fv was carried out by T.S. Experiments for functional analysis were designed by M.K. and D.D. and carried out by M.K., D.D., S.A.H. and A.A.Q. Modelling of GLUT5 was carried out by M.C. The manuscript was prepared by N.N., H.J.K., G.V., S.I. and D.D. All authors discussed the results and commented on the manuscript.

Competing interests

The authors declare no competing financial interests.

Corresponding authors

Correspondence to Norimichi Nomura or So Iwata or David Drew.

Extended data

Supplementary information


  1. 1.

    Video 1: Alternating access model of GLUT5 transport

    This video shows morphing between the open outward-facing, outward occluded, inward-occluded and open inward-facing GLUT5; conformations as viewed parallel to the membrane. The open outward- and inward-facing conformations are based on the GLUT5 structures reported in this study, and occluded states were modeled based on homologous XylE crystal structures (Methods). Morphing between conformations was generated using PyMol. Helix colouring is as in Fig. 1a.

  2. 2.

    Video 2: Alternating access model of GLUT5 transport

    This video shows the same as Video 1, but viewed from the extracellular side of the membrane.

  3. 3.

    Video 3: Alternating access model of GLUT5 transport

    This video shows the same as Video 1, but viewed from the intracellular side of the membrane.

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