Optical probing of a dynamic membrane interaction that regulates the TREK1 channel.
TREK channels produce background currents that regulate cell excitability. These channels are sensitive to a wide variety of stimuli including polyunsaturated fatty acids (PUFAs), phospholipids, mechanical stretch, and intracellular acidification. They are inhibited by neurotransmitters, hormones, and pharmacological agents such as the antidepressant fluoxetine. TREK1 knockout mice have impaired PUFA-mediated neuroprotection to ischemia, reduced sensitivity to volatile anesthetics, altered perception of pain, and a depression-resistant phenotype. Here, we investigate TREK1 regulation by Gq-coupled receptors (GqPCR) and phospholipids. Several reports indicate that the C-terminal domain of TREK1 is a key regulatory domain. We developed a fluorescent-based technique that monitors the plasma membrane association of the C terminus of TREK1 in real time. Our fluorescence and functional experiments link the modulation of TREK1 channel function by internal pH, phospholipid, and GqPCRs to TREK1-C-terminal domain association to the plasma membrane, where increased association results in greater activity. In keeping with this relation, inhibition of TREK1 current by fluoxetine is found to be accompanied by dissociation of the C-terminal domain from the membrane.
Department of Molecular and Cell Biology, Helen Wills Neuroscience Institute, University of California, Berkeley, CA 94720, USA.
Guillaume
G
Sandoz
Sarah C
SC
Bell
Ehud Y
EY
Isacoff
D000818:Animals; D018687:Antidepressive Agents, Second-Generation / Q000494:pharmacology; D002462:Cell Membrane / Q000235:genetics / Q000378:metabolism*; D005231:Fatty Acids, Unsaturated / Q000235:genetics / Q000378:metabolism; D005473:Fluoxetine / Q000494:pharmacology; D057809:HEK293 Cells; D006801:Humans; D006863:Hydrogen-Ion Concentration; D007511:Ischemia / Q000235:genetics / Q000378:metabolism; D051379:Mice; D018345:Mice, Knockout; D008856:Microscopy, Fluorescence; D009865:Oocytes; D010743:Phospholipids / Q000235:genetics / Q000378:metabolism*; D024683:Potassium Channels, Tandem Pore Domain / Q000235:genetics / Q000378:metabolism*; D017434:Protein Structure, Tertiary; D014982:Xenopus laevis
D018687:Antidepressive Agents, Second-Generation; D005231:Fatty Acids, Unsaturated; D010743:Phospholipids; D024683:Potassium Channels, Tandem Pore Domain; C103742:potassium channel protein TREK-1; D005473:Fluoxetine
Proc Natl Acad Sci U S A. 2009 Aug 25;106(34):14628-33
19667202
Sci STKE. 2003 Dec 16;2003(213):re16
14679290
EMBO J. 2000 Jun 1;19(11):2483-91
10835347
Science. 1996 Jan 12;271(5246):213-6
8539623
J Biol Chem. 1999 Dec 17;274(51):36065-72
10593888
Nat Chem Biol. 2010 May;6(5):369-75
20364128
Curr Protoc Cell Biol. 2009 Mar;Chapter 24:Unit 24.4
19283730
J Biol Chem. 2005 Aug 26;280(34):30175-84
16006563
J Biol Chem. 1999 Sep 17;274(38):26691-6
10480871
EMBO J. 2005 Jan 12;24(1):44-53
15577940
EMBO J. 2006 Jun 7;25(11):2368-76
16675954
Neuropsychopharmacology. 2008 Nov;33(12):2810-9
18288090
EMBO J. 2002 Jun 17;21(12):2968-76
12065410
J Biol Chem. 2000 Apr 7;275(14):10128-33
10744694
EMBO J. 1996 Dec 16;15(24):6854-62
9003761
Science. 2006 Dec 1;314(5804):1454-7
16990515
J Physiol. 2005 Apr 1;564(Pt 1):117-29
15677683
Mol Pharmacol. 2000 May;57(5):906-12
10779373
EMBO J. 2006 Dec 13;25(24):5864-72
17110924
EMBO J. 1998 Aug 3;17(15):4283-90
9687497
Biochem Soc Symp. 2005;(72):189-98
15649142
Nat Neurosci. 2006 Sep;9(9):1134-41
16906152
Neuron. 2008 May 22;58(4):546-56
18498736
Nat Cell Biol. 1999 Jul;1(3):183-8
10559906
Br J Pharmacol. 2005 Mar;144(6):821-9
15685212
Pflugers Arch. 2007 Oct;455(1):69-82
17473931
J Cell Biol. 2006 Nov 6;175(3):377-82
17088424
Nat Neurosci. 1999 May;2(5):422-6
10321245
Nature. 2005 Jun 30;435(7046):1239-43
15902207
Cytometry. 1997 Dec 1;29(4):286-91
9415410
EMBO J. 2004 Jul 7;23(13):2684-95
15175651
PLoS Biol. 2010 Apr 13;8(4):e1000355
20405001
J Neurosci. 2008 Aug 20;28(34):8545-52
18716213
EMBO J. 1998 Jun 15;17(12):3297-308
9628867
Nat Struct Mol Biol. 2008 Jan;15(1):106-8
18084307
Proc Natl Acad Sci U S A. 2003 Jan 21;100(2):745-50
12525701
J Biol Chem. 2009 Jan 23;284(4):2106-13
19047057
Proc Natl Acad Sci U S A. 2008 Sep 16;105(37):14163-8
18779583