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Updated: Sep 23, 2025

Measuring Nucleotide Binding to Intact, Functional Membrane Proteins in Real Time
Published on: March 11, 2021
Energetic differences between non-domain-swapped and domain-swapped chain connectivities in the K2P potassium channel
Carlos Navarro-Retamal1, Julio Caballero1
1Centro de Bioinformática y Simulación Molecular, Facultad de Ingeniería, Universidad de Talca 2 Norte 685, Casilla 721 Talca Chile jcaballero@utalca.cl +56-712-418-850.
Abstract:
Two-pore domain (K2P) channels are twofold symmetric K+ channels which control cell excitability by enabling the leak of potassium ions from cells in response to physicochemical stimuli. Crystallization of K2P channels revealed the presence of several structural features, which include an external cap. In the available crystallographic structures, the cap is present as non-domain-swapped (NDS) and domain-swapped (DS) chain conformations, where DS chain conformation exchanges two opposing outer helices 180° around the channel. In this work, energy differences between the residues located at the highest point of the cap in NDS and DS conformations were evaluated for TRAAK, a K2P channel that was crystallized in both conformations. Results indicated a preference for DS conformation, but this result is not extensible to TASK K2P channels.
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