View source for 7lrg


==Filamentous actin decorated with human cardiac myosin binding protein C C2 domain==
<StructureSection load='7lrg' size='340' side='right'caption='[[7lrg]], [[Resolution|resolution]] 6.10&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[7lrg]] is a 12 chain structure with sequence from [https://en.wikipedia.org/wiki/Homo_sapiens Homo sapiens] and [https://en.wikipedia.org/wiki/Sus_scrofa Sus scrofa]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=7LRG OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=7LRG 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]] 6.1&#8491;</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=7lrg FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=7lrg OCA], [https://pdbe.org/7lrg PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=7lrg RCSB], [https://www.ebi.ac.uk/pdbsum/7lrg PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=7lrg ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/B6VNT8_PIG B6VNT8_PIG] 
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
Cardiac muscle contraction depends on interactions between thick (myosin) and thin (actin) filaments (TFs). TFs are regulated by intracellular Ca(2+) levels. Under activating conditions Ca(2+) binds to the troponin complex and displaces tropomyosin from myosin binding sites on the TF surface to allow actomyosin interactions. Recent studies have shown that in addition to Ca(2+), the first four N-terminal domains (NTDs) of cardiac myosin binding protein C (cMyBP-C) (e.g. C0, C1, M and C2), are potent modulators of the TF activity, but the mechanism of their collective action is poorly understood. Previously, we showed that C1 activates the TF at low Ca(2+) and C0 stabilizes binding of C1 to the TF, but the ability of C2 to bind and/or affect the TF remains unknown. Here we obtained 7.5 A resolution cryo-EM reconstruction of C2-decorated actin filaments to demonstrate that C2 binds to actin in a single structural mode that does not activate the TF unlike the polymorphic binding of C0 and C1 to actin. Comparison of amino acid sequences of C2 with either C0 or C1 shows low levels of identity between the residues involved in interactions with the TF but high levels of conservation for residues involved in Ig fold stabilization. This provides a structural basis for strikingly different interactions of structurally homologous C0, C1 and C2 with the TF. Our detailed analysis of the interaction of C2 with the actin filament provides crucial information required to model the collective action of cMyBP-C NTDs on the cardiac TF.

Interaction of the C2 Ig-like Domain of Cardiac Myosin Binding Protein-C with F-actin.,Risi CM, Patra M, Belknap B, Harris SP, White HD, Galkin VE J Mol Biol. 2021 Sep 17;433(19):167178. doi: 10.1016/j.jmb.2021.167178. Epub 2021 , Jul 27. PMID:34329643<ref>PMID:34329643</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 7lrg" style="background-color:#fffaf0;"></div>

==See Also==
*[[Actin 3D structures|Actin 3D structures]]
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Homo sapiens]]
[[Category: Large Structures]]
[[Category: Sus scrofa]]
[[Category: Galkin VE]]