4RUE

Human K2P4.1 (TRAAK) potassium channel, G124I mutant

Summary for 4RUE

• Entry DOI: 10.2210/pdb4rue/pdb
• Related: 4RUF
• Descriptor: Potassium channel subfamily K member 4, POTASSIUM ION (2 entities in total)
• Functional Keywords: potassium ion channel, metal transport
• Biological source: Homo sapiens (human)
• Cellular location: Cell membrane ; Multi-pass membrane protein : Q9NYG8
• Total number of polymer chains: 2
• Total formula weight: 67518.41

Authors

Lolicato, M.,Minor, D.L.Jr. (deposition date: 2014-11-19, release date: 2014-12-17, Last modification date: 2024-11-06)

Primary citation

Lolicato, M.,Riegelhaupt, P.M.,Arrigoni, C.,Clark, K.A.,Minor, D.L.
Transmembrane Helix Straightening and Buckling Underlies Activation of Mechanosensitive and Thermosensitive K2P Channels.
Neuron, 84:1198-1212, 2014

PubMed Abstract: Mechanical and thermal activation of ion channels is central to touch, thermosensation, and pain. The TRAAK/TREK K(2P) potassium channel subfamily produces background currents that alter neuronal excitability in response to pressure, temperature, signaling lipids, and anesthetics. How such diverse stimuli control channel function is unclear. Here we report structures of K(2P)4.1 (TRAAK) bearing C-type gate-activating mutations that reveal a tilting and straightening of the M4 inner transmembrane helix and a buckling of the M2 transmembrane helix. These conformational changes move M4 in a direction opposite to that in classical potassium channel activation mechanisms and open a passage lateral to the pore that faces the lipid bilayer inner leaflet. Together, our findings uncover a unique aspect of K(2P) modulation, indicate a means for how the K(2P) C-terminal cytoplasmic domain affects the C-type gate which lies ∼40Å away, and suggest how lipids and bilayer inner leaflet deformations may gate the channel.

PubMed: 25500157
DOI: 10.1016/j.neuron.2014.11.017

Experimental method

X-RAY DIFFRACTION (3.3 Å)