6EO1

The electron crystallography structure of the cAMP-bound potassium channel MloK1 (PCO-refined)

Summary for 6EO1

• Entry DOI: 10.2210/pdb6eo1/pdb
• EMDB information: 3907
• Descriptor: Cyclic nucleotide-gated potassium channel mll3241, POTASSIUM ION (2 entities in total)
• Functional Keywords: mlok1, mlotik1, potassium channel, cnbd, cytoplasmic domains, pco refinement, membrane protein
• Biological source: Mesorhizobium loti MAFF303099
• Cellular location: Cell membrane; Multi-pass membrane protein: Q98GN8
• Total number of polymer chains: 4
• Total formula weight: 151143.38

Authors

Kowal, J.,Biyani, N.,Chami, M.,Scherer, S.,Rzepiela, A.,Baumgartner, P.,Upadhyay, V.,Nimigean, C.,Stahlberg, H. (deposition date: 2017-10-08, release date: 2017-12-27, Last modification date: 2024-11-06)

Primary citation

Kowal, J.,Biyani, N.,Chami, M.,Scherer, S.,Rzepiela, A.J.,Baumgartner, P.,Upadhyay, V.,Nimigean, C.M.,Stahlberg, H.
High-Resolution Cryoelectron Microscopy Structure of the Cyclic Nucleotide-Modulated Potassium Channel MloK1 in a Lipid Bilayer.
Structure, 26:20-27.e3, 2018

PubMed Abstract: Eukaryotic cyclic nucleotide-modulated channels perform their diverse physiological roles by opening and closing their pores to ions in response to cyclic nucleotide binding. We here present a structural model for the cyclic nucleotide-modulated potassium channel homolog from Mesorhizobium loti, MloK1, determined from 2D crystals in the presence of lipids. Even though crystals diffract electrons to only ∼10 Å, using cryoelectron microscopy (cryo-EM) and recently developed computational methods, we have determined a 3D map of full-length MloK1 in the presence of cyclic AMP (cAMP) at ∼4.5 Å isotropic 3D resolution. The structure provides a clear picture of the arrangement of the cyclic nucleotide-binding domains with respect to both the pore and the putative voltage sensor domains when cAMP is bound, and reveals a potential gating mechanism in the context of the lipid-embedded channel.

PubMed: 29249605
DOI: 10.1016/j.str.2017.11.012

Experimental method

ELECTRON CRYSTALLOGRAPHY (4.5 Å)