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5eik
From Proteopedia
(Difference between revisions)
(New page: '''Unreleased structure''' The entry 5eik is ON HOLD Authors: Hu, M.H., Yang, H.T., Liu, Z.F. Description: Category: Unreleased Structures Category: Liu, Z.F [[Category: Yang,...) |
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| - | '''Unreleased structure''' | ||
| - | + | ==Structure of a Trimeric Intracellular Cation channel from C. elegans in the absence of Ca2+== | |
| + | <StructureSection load='5eik' size='340' side='right'caption='[[5eik]], [[Resolution|resolution]] 2.30Å' scene=''> | ||
| + | == Structural highlights == | ||
| + | <table><tr><td colspan='2'>[[5eik]] is a 1 chain structure with sequence from [https://en.wikipedia.org/wiki/Caenorhabditis_elegans Caenorhabditis elegans]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=5EIK OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=5EIK FirstGlance]. <br> | ||
| + | </td></tr><tr id='method'><td class="sblockLbl"><b>[[Empirical_models|Method:]]</b></td><td class="sblockDat" id="methodDat">X-ray diffraction, [[Resolution|Resolution]] 2.3Å</td></tr> | ||
| + | <tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=ACT:ACETATE+ION'>ACT</scene>, <scene name='pdbligand=CPL:1-PALMITOYL-2-LINOLEOYL-SN-GLYCERO-3-PHOSPHOCHOLINE'>CPL</scene>, <scene name='pdbligand=DMU:DECYL-BETA-D-MALTOPYRANOSIDE'>DMU</scene>, <scene name='pdbligand=MG:MAGNESIUM+ION'>MG</scene>, <scene name='pdbligand=PT5:(1S)-2-{[(R)-HYDROXY{[(1R,2R,3S,4R,5R,6S)-2,3,6-TRIHYDROXY-4,5-BIS(PHOSPHONOOXY)CYCLOHEXYL]OXY}PHOSPHORYL]OXY}-1-[(OCTADECANOYLOXY)METHYL]ETHYL+(8E,11E)-ICOSA-5,8,11,14-TETRAENOATE'>PT5</scene></td></tr> | ||
| + | <tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[https://proteopedia.org/fgij/fg.htm?mol=5eik FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=5eik OCA], [https://pdbe.org/5eik PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=5eik RCSB], [https://www.ebi.ac.uk/pdbsum/5eik PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=5eik ProSAT]</span></td></tr> | ||
| + | </table> | ||
| + | == Function == | ||
| + | [https://www.uniprot.org/uniprot/T38B2_CAEEL T38B2_CAEEL] Potassium channel that mediates transmembrane potassium transport (By similarity). Might be required for maintenance of rapid intracellular calcium release (By similarity). May act as a potassium counter-ion channel that functions in synchronization with calcium release from intracellular stores (By similarity). Binds phosphatidylinositol 4,5-bisphosphate (PIP2) (PubMed:27698420).[UniProtKB:Q9DAV9][UniProtKB:Q9NA75]<ref>PMID:27698420</ref> | ||
| + | <div style="background-color:#fffaf0;"> | ||
| + | == Publication Abstract from PubMed == | ||
| + | Intracellular Ca(2+) signalling processes are fundamental to muscle contraction, neurotransmitter release, cell growth and apoptosis. Release of Ca(2+) from the intracellular stores is supported by a series of ion channels in sarcoplasmic or endoplasmic reticulum (SR/ER). Among them, two isoforms of the trimeric intracellular cation (TRIC) channel family, named TRIC-A and TRIC-B, modulate the release of Ca(2+) through the ryanodine receptor or inositol triphosphate receptor, and maintain the homeostasis of ions within SR/ER lumen. Genetic ablations or mutations of TRIC channels are associated with hypertension, heart disease, respiratory defects and brittle bone disease. Despite the pivotal function of TRIC channels in Ca(2+) signalling, their pore architectures and gating mechanisms remain unknown. Here we present the structures of TRIC-B1 and TRIC-B2 channels from Caenorhabditis elegans in complex with endogenous phosphatidylinositol-4,5-biphosphate (PtdIns(4,5)P2, also known as PIP2) lipid molecules. The TRIC-B1/B2 proteins and PIP2 assemble into a symmetrical homotrimeric complex. Each monomer contains an hourglass-shaped hydrophilic pore contained within a seven-transmembrane-helix domain. Structural and functional analyses unravel the central role of PIP2 in stabilizing the cytoplasmic gate of the ion permeation pathway and reveal a marked Ca(2+)-induced conformational change in a cytoplasmic loop above the gate. A mechanistic model has been proposed to account for the complex gating mechanism of TRIC channels. | ||
| - | + | Pore architecture of TRIC channels and insights into their gating mechanism.,Yang H, Hu M, Guo J, Ou X, Cai T, Liu Z Nature. 2016 Oct 27;538(7626):537-541. doi: 10.1038/nature19767. Epub 2016 Oct 3. PMID:27698420<ref>PMID:27698420</ref> | |
| - | + | From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.<br> | |
| - | [[Category: | + | </div> |
| - | [[Category: | + | <div class="pdbe-citations 5eik" style="background-color:#fffaf0;"></div> |
| - | [[Category: | + | == References == |
| - | [[Category: | + | <references/> |
| + | __TOC__ | ||
| + | </StructureSection> | ||
| + | [[Category: Caenorhabditis elegans]] | ||
| + | [[Category: Large Structures]] | ||
| + | [[Category: Hu MH]] | ||
| + | [[Category: Liu ZF]] | ||
| + | [[Category: Yang HT]] | ||
Current revision
Structure of a Trimeric Intracellular Cation channel from C. elegans in the absence of Ca2+
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