title: Crystal structure of a Kir3.1-prokaryotic Kir channel chimera.
abstract: The Kir3.1 K(+) channel participates in heart rate control and neuronal excitability through G-protein and lipid signaling pathways. Expression in Escherichia coli has been achieved by replacing three fourths of the transmembrane pore with the pore of a prokaryotic Kir channel, leaving the cytoplasmic pore and membrane interfacial regions of Kir3.1 origin. Two structures were determined at 2.2 A. The selectivity filter is identical to the Streptomyces lividans K(+) channel within error of measurement (r.m.s.d.<0.2 A), suggesting that K(+) selectivity requires extreme conservation of three-dimensional structure. Multiple K(+) ions reside within the pore and help to explain voltage-dependent Mg(2+) and polyamine blockade and strong rectification. Two constrictions, at the inner helix bundle and at the apex of the cytoplasmic pore, may function as gates: in one structure the apex is open and in the other, it is closed. Gating of the apex is mediated by rigid-body movements of the cytoplasmic pore subunits. Phosphatidylinositol 4,5-biphosphate-interacting residues suggest a possible mechanism by which the signaling lipid regulates the cytoplasmic pore.
authors: Laboratory of Molecular Neurobiology and Biophysics, Howard Hughes Medical Institute, Rockefeller University, New York, NY 10065, USA.
authors: Motohiko
authors: M
authors: Nishida
authors: Martine
authors: M
authors: Cadene
authors: Brian T
authors: BT
authors: Chait
authors: Roderick
authors: R
authors: MacKinnon
mesh_terms: D000595:Amino Acid Sequence; D001426:Bacterial Proteins / Q000235:genetics*; D001665:Binding Sites; D019117:Burkholderia / Q000378:metabolism; D018360:Crystallography, X-Ray; D004926:Escherichia coli / Q000378:metabolism; D051676:G Protein-Coupled Inwardly-Rectifying Potassium Channels / Q000096:biosynthesis / Q000737:chemistry* / Q000235:genetics; D015640:Ion Channel Gating; D008958:Models, Molecular; D008969:Molecular Sequence Data; D011487:Protein Conformation; D011993:Recombinant Fusion Proteins / Q000096:biosynthesis / Q000737:chemistry* / Q000235:genetics
chemical_list: D001426:Bacterial Proteins; D051676:G Protein-Coupled Inwardly-Rectifying Potassium Channels; D011993:Recombinant Fusion Proteins
references: J Biol Chem. 1999 Apr 30;274(18):12517-24
references: 10212228
references: Proc Natl Acad Sci U S A. 1999 May 11;96(10):5820-5
references: 10318968
references: Nat Cell Biol. 1999 Jul;1(3):183-8
references: 10559906
references: J Gen Physiol. 2000 Nov;116(5):599-608
references: 11055989
references: Neuron. 2001 Mar;29(3):657-67
references: 11301025
references: Neuron. 2001 Mar;29(3):669-80
references: 11301026
references: Mol Pharmacol. 2001 May;59(5):1086-93
references: 11306691
references: Cell. 2001 May 18;105(4):511-9
references: 11371347
references: Nature. 2001 Nov 1;414(6859):43-8
references: 11689936
references: Sci STKE. 2001 Dec 04;2001(111):re19
references: 11734659
references: BMC Evol Biol. 2001;1:14
references: 11806753
references: Am J Physiol Renal Physiol. 2002 May;282(5):F826-34
references: 11934692
references: Neuron. 2002 Jun 13;34(6):933-44
references: 12086641
references: J Clin Invest. 2002 Aug;110(3):381-8
references: 12163457
references: Rev Physiol Biochem Pharmacol. 2002;145:47-179
references: 12224528
references: Cell. 2002 Dec 27;111(7):957-65
references: 12507423
references: J Biol Chem. 2003 Mar 21;278(12):10500-5
references: 12514171
references: J Membr Biol. 2003 Mar 15;192(2):111-22
references: 12682799
references: Science. 2003 Jun 20;300(5627):1922-6
references: 12738871
references: J Biol Chem. 2003 Aug 1;278(31):29174-83
references: 12743112
references: Biophys J. 2003 Jun;84(6):3717-29
references: 12770878
references: J Biol Chem. 2003 Dec 19;278(51):51779-85
references: 14522976
references: J Gen Physiol. 2003 Nov;122(5):485-500
references: 14581581
references: J Mol Biol. 2003 Nov 7;333(5):965-75
references: 14583193
references: J Physiol. 2004 Mar 16;555(Pt 3):643-57
references: 14724209
references: Annu Rev Physiol. 2004;66:103-29
references: 14977398
references: J Biol Chem. 2004 Sep 3;279(36):37271-81
references: 15155739
references: Acta Crystallogr D Biol Crystallogr. 1994 Sep 1;50(Pt 5):760-3
references: 15299374
references: Physiol Rev. 2005 Jan;85(1):319-71
references: 15618483
references: EMBO J. 2005 Jan 26;24(2):229-39
references: 15650751
references: Nat Neurosci. 2005 Mar;8(3):279-87
references: 15723059
references: J Physiol. 2005 Apr 15;564(Pt 2):489-500
references: 15731196
references: J Gen Physiol. 2005 Apr;125(4):413-26
references: 15795311
references: EMBO Rep. 2005 May;6(5):470-5
references: 15864298
references: Diabetes. 2005 Sep;54(9):2503-13
references: 16123337
references: J Physiol. 2006 Mar 1;571(Pt 2):303-17
references: 16373383
references: Biochem Soc Trans. 2006 Apr;34(Pt 2):243-6
references: 16545085
references: EMBO Rep. 2006 Jun;7(6):611-6
references: 16641935
references: Biochemistry. 2006 Jul 18;45(28):8599-606
references: 16834334
references: Biophys J. 2006 Oct 15;91(8):2901-9
references: 16891366
references: J Biol Chem. 2007 Feb 23;282(8):5781-9
references: 17166852
references: PLoS Biol. 2007 May;5(5):e121
references: 17472437
references: Nature. 1987 Jan 22-28;325(6102):321-6
references: 2433589
references: Nature. 1987 Jan 8-14;325(7000):156-9
references: 2433601
references: Proc Natl Acad Sci U S A. 1987 Apr;84(8):2560-4
references: 2436236
references: Methods Enzymol. 1997;276:307-26
references: 27754618
references: Science. 1995 Apr 21;268(5209):423-6
references: 7716547
references: Neuron. 1995 May;14(5):1047-54
references: 7748552
references: Nature. 1995 Mar 9;374(6518):135-41
references: 7877685
references: Nature. 1994 Nov 24;372(6504):366-9
references: 7969496
references: Nature. 1994 Jul 14;370(6485):143-6
references: 8022483
references: Nature. 1994 Mar 17;368(6468):255-7
references: 8145826
references: Science. 1994 May 6;264(5160):844-7
references: 8171340
references: Science. 1996 Aug 16;273(5277):956-9
references: 8688080
references: Nat Genet. 1996 Oct;14(2):152-6
references: 8841184
references: J Biol Chem. 1997 Feb 28;272(9):5388-95
references: 9038137
references: Nature. 1998 Feb 19;391(6669):803-6
references: 9486652
references: Science. 1998 Apr 3;280(5360):69-77
references: 9525859
references: J Gen Physiol. 1998 Sep;112(3):333-49
references: 9725893
references: Acta Crystallogr D Biol Crystallogr. 1998 Sep 1;54(Pt 5):905-21
references: 9757107
references: Science. 1998 Nov 6;282(5391):1138-41
references: 9804554
references: Science. 1998 Nov 6;282(5391):1141-4
references: 9804555