Molecule of the Month: Glucose Transporters
Glucose transporters deliver glucose molecules one-by-one across cell membranes.
Exploring the Structure
GLUT5, a fructose transporter (PDB entries 4ybq, 4yb9), has been caught in both the outward open and inward open states. GLUT1 (PDB entry 5eqi) has also been studied in a complex with the inhibitor cytochalasin B, which freezes the transporter in one state and blocks transport. Unwanted inhibition of glucose transporters can be important in medicine—for example, HIV protease inhibitors block the action of GLUT4 and lead to side effects during treatment. To explore these structures in more detail, click on the image for an interactive JSmol.
Topics for Further Discussion
- Many structures of these types of transporters are available—try searching for “major facilitator” to see some of them.
- When you’re looking at these proteins or other membrane-bound proteins, you can highlight the membrane-spanning portion by displaying a molecular surface and coloring it by hydrophobicity.
- 5eqi: K Kapoor, JS Finer-Moore, BP Pedersen, L Caboni, A Waight, RC Hillig, P Bringmann, I Heisler, T Muller, H Siebeneicher & RM Stroud (2016) Mechanism of inhibition of human glucose transporter GLUT1 is conserved between cytochalasin B and phenyalanine amides. Proceedings of the National Academy of Science USA 113, 4711-4716.
- EM Quistgaard, C Low, F Guettou & P Norlund (2016) Understanding transport by the major facilitator superfamily (MFS): structures pave the way. Nature Reviews Molecular Cell Biology 17, 123-132.
- 4zwc: D Deng, PC Sun, CY Yan, M Ke, X Jiang, L Xiong, W Ren, K Hirata, M Yamamoto, S Fan & N Yan (2015) Molecular basis of ligand recognition and transport by glucose transporters. Nature 526, 391-396.
- 4yb9, 4ybq: N Nomura, G Verdon, HJ Kang, T Shimamura, Y Nomura, Y Sonoda, SA Hussien, AA Qureshi, M Coincon, Y Sato, H Abe, Y Nakada-Nakura, T Hino, T Arakawa, O Kusano-Arai, H Iwanari, T Murata, T Kobayashi, T Hamakubo, M Kasahara, S Iwata & D Drew (2015) Structure and mechanism of the mammalian fructose transporter GLUT5. Nature 526, 397-401.
- 4pyp: D Deng, C Xu, PC Sun, JP Wu, CY Yan, MX Hu & N Yan (2014) Crystal structure of the human glucose transporter GLUT1. Nature 510, 121-125.
- M Mueckler & B Thorens (2013) The SLC2 (GLUT) family of membrane transporters. Molecular Aspects of Medicine 34, 121-138.
- JS Bogan (2012) Regulation of glucose transporter translocation in health and diabetes. Annual Review of Biochemistry 81, 507-532.
- 1pv6: J Abramson, I Smirnova, V Kasho, G Verner, HR Kaback & S Iwata (2003) Structure and mechanism of the lactose permease of Escherichia coli. Science 301, 610-615.
- 1pw4: Y Huang, MJ Lemieux, J Song, M Auer & DN Wang (2003) Structure and mechanism of the glycerol-3-phosphate transporter from Escherichia coli. Science 301, 616-620.
April 2017, David Goodsellhttp://doi.org/10.2210/rcsb_pdb/mom_2017_4