6ZGD
GLIC pentameric ligand-gated ion channel, pH 7
Summary for 6ZGD
| Entry DOI | 10.2210/pdb6zgd/pdb |
| EMDB information | 11202 |
| Descriptor | Proton-gated ion channel (1 entity in total) |
| Functional Keywords | glic, pentameric ligand-gated ion channel, cryoem, membrane protein |
| Biological source | Gloeobacter violaceus (strain ATCC 29082 / PCC 7421) |
| Total number of polymer chains | 5 |
| Total formula weight | 181458.75 |
| Authors | Rovsnik, U.,Zhuang, Y.,Forsberg, B.O.,Carroni, M.,Yvonnesdotter, L.,Howard, R.J.,Lindahl, E. (deposition date: 2020-06-18, release date: 2021-05-26, Last modification date: 2024-07-10) |
| Primary citation | Rovsnik, U.,Zhuang, Y.,Forsberg, B.O.,Carroni, M.,Yvonnesdotter, L.,Howard, R.J.,Lindahl, E. Dynamic closed states of a ligand-gated ion channel captured by cryo-EM and simulations. Life Sci Alliance, 4:-, 2021 Cited by PubMed Abstract: Ligand-gated ion channels are critical mediators of electrochemical signal transduction across evolution. Biophysical and pharmacological characterization of these receptor proteins relies on high-quality structures in multiple, subtly distinct functional states. However, structural data in this family remain limited, particularly for resting and intermediate states on the activation pathway. Here, we report cryo-electron microscopy (cryo-EM) structures of the proton-activated ligand-gated ion channel (GLIC) under three pH conditions. Decreased pH was associated with improved resolution and side chain rearrangements at the subunit/domain interface, particularly involving functionally important residues in the β1-β2 and M2-M3 loops. Molecular dynamics simulations substantiated flexibility in the closed-channel extracellular domains relative to the transmembrane ones and supported electrostatic remodeling around E35 and E243 in proton-induced gating. Exploration of secondary cryo-EM classes further indicated a low-pH population with an expanded pore. These results allow us to define distinct protonation and activation steps in pH-stimulated conformational cycling in GLIC, including interfacial rearrangements largely conserved in the pentameric channel family. PubMed: 34210687DOI: 10.26508/lsa.202101011 PDB entries with the same primary citation |
| Experimental method | ELECTRON MICROSCOPY (4.1 Å) |
Structure validation
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