This old version of Proteopedia is provided for student assignments while the new version is undergoing repairs. Content and edits done in this old version of Proteopedia after March 1, 2026 will eventually be lost when it is retired in about June of 2026.
Apply for new accounts at the new Proteopedia. Your logins will work in both the old and new versions.
8tke
From Proteopedia
(Difference between revisions)
(New page: '''Unreleased structure''' The entry 8tke is ON HOLD until sometime in the future Authors: Paknejad, N., Sapuru, V., Hite, R.K. Description: Human Type 3 IP3 Receptor -Preactivated+Ca2...) |
|||
| (2 intermediate revisions not shown.) | |||
| Line 1: | Line 1: | ||
| - | '''Unreleased structure''' | ||
| - | + | ==Human Type 3 IP3 Receptor - Preactivated+Ca2+ State (+IP3/ATP/JD Ca2+)== | |
| + | <StructureSection load='8tke' size='340' side='right'caption='[[8tke]], [[Resolution|resolution]] 3.60Å' scene=''> | ||
| + | == Structural highlights == | ||
| + | <table><tr><td colspan='2'>[[8tke]] is a 4 chain structure with sequence from [https://en.wikipedia.org/wiki/Homo_sapiens Homo sapiens]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=8TKE OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=8TKE FirstGlance]. <br> | ||
| + | </td></tr><tr id='method'><td class="sblockLbl"><b>[[Empirical_models|Method:]]</b></td><td class="sblockDat" id="methodDat">Electron Microscopy, [[Resolution|Resolution]] 3.6Å</td></tr> | ||
| + | <tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=ATP:ADENOSINE-5-TRIPHOSPHATE'>ATP</scene>, <scene name='pdbligand=CA:CALCIUM+ION'>CA</scene>, <scene name='pdbligand=I3P:D-MYO-INOSITOL-1,4,5-TRIPHOSPHATE'>I3P</scene>, <scene name='pdbligand=ZN:ZINC+ION'>ZN</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=8tke FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=8tke OCA], [https://pdbe.org/8tke PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=8tke RCSB], [https://www.ebi.ac.uk/pdbsum/8tke PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=8tke ProSAT]</span></td></tr> | ||
| + | </table> | ||
| + | == Function == | ||
| + | [https://www.uniprot.org/uniprot/ITPR3_HUMAN ITPR3_HUMAN] Receptor for inositol 1,4,5-trisphosphate, a second messenger that mediates the release of intracellular calcium. | ||
| + | <div style="background-color:#fffaf0;"> | ||
| + | == Publication Abstract from PubMed == | ||
| + | Inositol 1,4,5-trisphosphate receptors (IP(3)Rs) are endoplasmic reticulum Ca(2+) channels whose biphasic dependence on cytosolic Ca(2+) gives rise to Ca(2+) oscillations that regulate fertilization, cell division and cell death. Despite the critical roles of IP(3)R-mediated Ca(2+) responses, the structural underpinnings of the biphasic Ca(2+) dependence that underlies Ca(2+) oscillations are incompletely understood. Here, we collect cryo-EM images of an IP(3)R with Ca(2+) concentrations spanning five orders of magnitude. Unbiased image analysis reveals that Ca(2+) binding does not explicitly induce conformational changes but rather biases a complex conformational landscape consisting of resting, preactivated, activated, and inhibited states. Using particle counts as a proxy for relative conformational free energy, we demonstrate that Ca(2+) binding at a high-affinity site allows IP(3)Rs to activate by escaping a low-energy resting state through an ensemble of preactivated states. At high Ca(2+) concentrations, IP(3)Rs preferentially enter an inhibited state stabilized by a second, low-affinity Ca(2+) binding site. Together, these studies provide a mechanistic basis for the biphasic Ca(2+)-dependence of IP(3)R channel activity. | ||
| - | + | Structural titration reveals Ca(2+)-dependent conformational landscape of the IP(3) receptor.,Paknejad N, Sapuru V, Hite RK Nat Commun. 2023 Oct 28;14(1):6897. doi: 10.1038/s41467-023-42707-3. PMID:37898605<ref>PMID:37898605</ref> | |
| - | + | From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.<br> | |
| - | [[Category: | + | </div> |
| - | [[Category: | + | <div class="pdbe-citations 8tke" style="background-color:#fffaf0;"></div> |
| - | [[Category: Hite | + | == References == |
| - | [[Category: Sapuru | + | <references/> |
| + | __TOC__ | ||
| + | </StructureSection> | ||
| + | [[Category: Homo sapiens]] | ||
| + | [[Category: Large Structures]] | ||
| + | [[Category: Hite RK]] | ||
| + | [[Category: Paknejad N]] | ||
| + | [[Category: Sapuru V]] | ||
Current revision
Human Type 3 IP3 Receptor - Preactivated+Ca2+ State (+IP3/ATP/JD Ca2+)
| |||||||||||
