The structure, function and distribution of the mouse TWIK-1 K+ channel.
The two P domain K+ channel mTWIK-1 has been cloned from mouse brain. In Xenopus oocytes, mTWIK-1 currents are K+-selective, instantaneous, and weakly inward rectifying. These currents are blocked by Ba2+ and quinine, decreased by protein kinase C and increased by internal acidification. The apparent molecular weight of mTWIK-1 in brain is 81 kDa. A 40 kDa form is revealed after treatment with a reducing agent, strongly suggesting that native mTWIK-1 subunits dimerize via a disulfide bridge. TWIK-1 mRNA is expressed abundantly in brain and at lower levels in lung, kidney, and skeletal muscle. In situ hybridization shows that mTWIK-1 expression is restricted to a few brain regions, with the highest levels in cerebellar granule cells, brainstem, hippocampus and cerebral cortex.
Lesage
F
F
Institut de Pharmacologie Moléculaire et Cellulaire, CNRS, 660, Valbonne, France.
Lauritzen
I
I
Duprat
F
F
Reyes
R
R
Fink
M
M
Heurteaux
C
C
Lazdunski
M
M
D000595:Amino Acid Sequence; D000818:Animals; D001464:Barium / Q000494:pharmacology; D001483:Base Sequence; D015153:Blotting, Western; D001921:Brain / Q000378:metabolism*; D018076:DNA, Complementary / Q000235:genetics; D019281:Dimerization; D017403:In Situ Hybridization; D008564:Membrane Potentials; D051379:Mice; D008969:Molecular Sequence Data; D008970:Molecular Weight; D009865:Oocytes; D015221:Potassium Channels / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D024683:Potassium Channels, Tandem Pore Domain; D011803:Quinine / Q000494:pharmacology; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D014981:Xenopus
D018076:DNA, Complementary; C486372:Kcnk1 protein, mouse; D015221:Potassium Channels; D024683:Potassium Channels, Tandem Pore Domain; D012333:RNA, Messenger; D001464:Barium; D011803:Quinine