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1jq2

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Revision as of 03:21, 10 September 2015

POTASSIUM CHANNEL (KCSA) OPEN GATE MODEL

Structural highlights

1jq2 is a 4 chain structure with sequence from "actinomyces_lividans"_krasil'nikov_et_al._1965 "actinomyces lividans" krasil'nikov et al. 1965. Full experimental information is available from OCA. For a guided tour on the structure components use FirstGlance.
Related:	1jq1
Resources:	FirstGlance, OCA, PDBe, RCSB, PDBsum

Function

[KCSA_STRLI] Acts as a pH-gated potassium ion channel; changing the cytosolic pH from 7 to 4 opens the channel, although it is not clear if this is the physiological stimulus for channel opening. Monovalent cation preference is K(+) > Rb(+) > NH4(+) >> Na(+) > Li(+).^[1]

Publication Abstract from PubMed

Ion channels catalyze the selective transfer of ions across the membrane in response to a variety of stimuli. These channels gate by controlling the access of ions to a centrally located water-filled pore. The crystal structure of the Streptomyces lividans potassium channel (KcsA) has allowed a molecular exploration of this mechanism. Electron paramagnetic resonance (EPR) studies have uncovered significant conformational changes at the intracellular end of the second transmembrane helix (TM2) upon gating. We have used site-directed spin labeling (SDSL) and EPR spectroscopy in an attempt to quantify the structural rearrangements of the KcsA TM2 bundle underlying the transition from the closed to the open state. Under conditions favoring the closed and open conformations, 10 intersubunit distances were obtained across TM2 segments from tandem dimer constructs. Analysis of these data points to a mechanism in which each TM2 helix tilts away from the permeation pathway, towards the membrane plane, and rotates about its helical axis, supporting a scissoring-type motion with a pivot point near residues 107-108. These movements are accompanied by a large increase in the diameter of the vestibule below the central water-filled cavity.

Structure of the KcsA channel intracellular gate in the open state.,Liu YS, Sompornpisut P, Perozo E Nat Struct Biol. 2001 Oct;8(10):883-7. PMID:11573095^[2]

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

References

↑ Schrempf H, Schmidt O, Kummerlen R, Hinnah S, Muller D, Betzler M, Steinkamp T, Wagner R. A prokaryotic potassium ion channel with two predicted transmembrane segments from Streptomyces lividans. EMBO J. 1995 Nov 1;14(21):5170-8. PMID:7489706
↑ Liu YS, Sompornpisut P, Perozo E. Structure of the KcsA channel intracellular gate in the open state. Nat Struct Biol. 2001 Oct;8(10):883-7. PMID:11573095 doi:10.1038/nsb1001-883

1 Structural highlights
2 Function
3 Publication Abstract from PubMed
4 See Also
5 References

Proteopedia Page Contributors and Editors (what is this?)

OCA

Retrieved from "http://52.214.119.220/wiki/index.php/1jq2"

@@ Line 2: / Line 2: @@
 <StructureSection load='1jq2' size='340' side='right' caption='[[1jq2]], [[NMR_Ensembles_of_Models | 50 NMR models]]' scene=''>
 == Structural highlights ==
-<table><tr><td colspan='2'>[[1jq2]] is a 4 chain structure with sequence from [http://en.wikipedia.org/wiki/Streptomyces_lividans Streptomyces lividans]. Full experimental information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1JQ2 OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=1JQ2 FirstGlance]. <br>
+<table><tr><td colspan='2'>[[1jq2]] is a 4 chain structure with sequence from [http://en.wikipedia.org/wiki/"actinomyces_lividans"_krasil'nikov_et_al._1965 "actinomyces lividans" krasil'nikov et al. 1965]. Full experimental information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1JQ2 OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=1JQ2 FirstGlance]. <br>
 </td></tr><tr id='related'><td class="sblockLbl"><b>[[Related_structure|Related:]]</b></td><td class="sblockDat">[[1jq1|1jq1]]</td></tr>
-<tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=1jq2 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1jq2 OCA], [http://www.rcsb.org/pdb/explore.do?structureId=1jq2 RCSB], [http://www.ebi.ac.uk/pdbsum/1jq2 PDBsum]</span></td></tr>
+<tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=1jq2 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1jq2 OCA], [http://pdbe.org/1jq2 PDBe], [http://www.rcsb.org/pdb/explore.do?structureId=1jq2 RCSB], [http://www.ebi.ac.uk/pdbsum/1jq2 PDBsum]</span></td></tr>
 </table>
 == Function ==
@@ Line 16: / Line 16: @@
 From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
 </div>
+<div class="pdbe-citations 1jq2" style="background-color:#fffaf0;"></div>
 ==See Also==
@@ Line 24: / Line 25: @@
 __TOC__
 </StructureSection>
-[[Category: Streptomyces lividans]]
+[[Category: Actinomyces lividans krasil'nikov et al. 1965]]
 [[Category: Liu, Y S]]
 [[Category: Perozo, E]]

1jq2

From Proteopedia

Revision as of 03:21, 10 September 2015

POTASSIUM CHANNEL (KCSA) OPEN GATE MODEL

Structural highlights

Function

Publication Abstract from PubMed

See Also

References

Contents

Proteopedia Page Contributors and Editors (what is this?)

Views

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