6pis

From Proteopedia

Mouse two pore domain K+ channel TRAAK (K2P4.1) - Fab complex structure

Structural highlights

6pis is a 6 chain structure with sequence from Mus musculus and Nothocricetulus migratorius. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance.
Method:	X-ray diffraction, Resolution 2.77Å
Ligands:	K
Resources:	FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT

Function

KCNK4_MOUSE Voltage-insensitive potassium channel (PubMed:9628867). Channel opening is triggered by mechanical forces that deform the membrane. Channel opening is triggered by raising the intracellular pH to basic levels (By similarity). The channel is inactive at 24 degrees Celsius (in vitro); raising the temperature to 37 degrees Celsius increases the frequency of channel opening, with a further increase in channel activity when the temperature is raised to 42 degrees Celsius (By similarity). Plays a role in the sensory perception of pain caused by pressure (PubMed:19279663). Plays a role in the perception of pain caused by heat (PubMed:19279663).[UniProtKB:G3V8V5]^[1] ^[2]

Publication Abstract from PubMed

TRAAK is a membrane tension-activated K(+) channel that has been associated through behavioral studies to mechanical nociception. We used specific monoclonal antibodies in mice to show that TRAAK is localized exclusively to nodes of Ranvier, the action potential propagating elements of myelinated nerve fibers. Approximately 80 percent of myelinated nerve fibers throughout the central and peripheral nervous system contain TRAAK in what is likely an all-nodes or no-nodes per axon fashion. TRAAK is not observed at the axon initial segment where action potentials are first generated. We used polyclonal antibodies, the TRAAK inhibitor RU2 and node clamp amplifiers to demonstrate the presence and functional properties of TRAAK in rat nerve fibers. TRAAK contributes to the 'leak' K(+) current in mammalian nerve fiber conduction by hyperpolarizing the resting membrane potential, thereby increasing Na(+) channel availability for action potential propagation. We speculate on why nodes of Ranvier contain a mechanosensitive K(+) channel.

The mechanosensitive ion channel TRAAK is localized to the mammalian node of Ranvier.,Brohawn SG, Wang W, Handler A, Campbell EB, Schwarz JR, MacKinnon R Elife. 2019 Nov 1;8. pii: 50403. doi: 10.7554/eLife.50403. PMID:31674909^[3]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.

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Citations

reviews cite this structure

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References

↑ Noel J, Zimmermann K, Busserolles J, Deval E, Alloui A, Diochot S, Guy N, Borsotto M, Reeh P, Eschalier A, Lazdunski M. The mechano-activated K+ channels TRAAK and TREK-1 control both warm and cold perception. EMBO J. 2009 May 6;28(9):1308-18. doi: 10.1038/emboj.2009.57. Epub 2009 Mar 12. PMID:19279663 doi:http://dx.doi.org/10.1038/emboj.2009.57
↑ Fink M, Lesage F, Duprat F, Heurteaux C, Reyes R, Fosset M, Lazdunski M. A neuronal two P domain K+ channel stimulated by arachidonic acid and polyunsaturated fatty acids. EMBO J. 1998 Jun 15;17(12):3297-308. doi: 10.1093/emboj/17.12.3297. PMID:9628867 doi:http://dx.doi.org/10.1093/emboj/17.12.3297
↑ Brohawn SG, Wang W, Handler A, Campbell EB, Schwarz JR, MacKinnon R. The mechanosensitive ion channel TRAAK is localized to the mammalian node of Ranvier. Elife. 2019 Nov 1;8. pii: 50403. doi: 10.7554/eLife.50403. PMID:31674909 doi:http://dx.doi.org/10.7554/eLife.50403