View source for 6sl2


==ALPHA-ACTININ FROM ENTAMOEBA HISTOLYTICA==
<StructureSection load='6sl2' size='340' side='right'caption='[[6sl2]], [[Resolution|resolution]] 3.10&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[6sl2]] is a 1 chain structure with sequence from [http://en.wikipedia.org/wiki/Enthi Enthi]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=6SL2 OCA]. For a <b>guided tour on the structure components</b> use [http://proteopedia.org/fgij/fg.htm?mol=6SL2 FirstGlance]. <br>
</td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=CA:CALCIUM+ION'>CA</scene>, <scene name='pdbligand=MG:MAGNESIUM+ION'>MG</scene>, <scene name='pdbligand=TRS:2-AMINO-2-HYDROXYMETHYL-PROPANE-1,3-DIOL'>TRS</scene></td></tr>
<tr id='NonStdRes'><td class="sblockLbl"><b>[[Non-Standard_Residue|NonStd Res:]]</b></td><td class="sblockDat"><scene name='pdbligand=MLZ:N-METHYL-LYSINE'>MLZ</scene></td></tr>
<tr id='related'><td class="sblockLbl"><b>[[Related_structure|Related:]]</b></td><td class="sblockDat">[[5nl7|5nl7]], [[5nl6|5nl6]]</td></tr>
<tr id='gene'><td class="sblockLbl"><b>[[Gene|Gene:]]</b></td><td class="sblockDat">CL6EHI_199000, EHI_199000 ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=5759 ENTHI])</td></tr>
<tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[http://proteopedia.org/fgij/fg.htm?mol=6sl2 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=6sl2 OCA], [http://pdbe.org/6sl2 PDBe], [http://www.rcsb.org/pdb/explore.do?structureId=6sl2 RCSB], [http://www.ebi.ac.uk/pdbsum/6sl2 PDBsum], [http://prosat.h-its.org/prosat/prosatexe?pdbcode=6sl2 ProSAT]</span></td></tr>
</table>
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
The actin cytoskeleton, a dynamic network of actin filaments and associated F-actin-binding proteins, is fundamentally important in eukaryotes. alpha-Actinins are major F-actin bundlers that are inhibited by Ca(2+) in nonmuscle cells. Here we report the mechanism of Ca(2+)-mediated regulation of Entamoeba histolytica alpha-actinin-2 (EhActn2) with features expected for the common ancestor of Entamoeba and higher eukaryotic alpha-actinins. Crystal structures of Ca(2+)-free and Ca(2+)-bound EhActn2 reveal a calmodulin-like domain (CaMD) uniquely inserted within the rod domain. Integrative studies reveal an exceptionally high affinity of the EhActn2 CaMD for Ca(2+), binding of which can only be regulated in the presence of physiological concentrations of Mg(2+) Ca(2+) binding triggers an increase in protein multidomain rigidity, reducing conformational flexibility of F-actin-binding domains via interdomain cross-talk and consequently inhibiting F-actin bundling. In vivo studies uncover that EhActn2 plays an important role in phagocytic cup formation and might constitute a new drug target for amoebic dysentery.

Calcium modulates the domain flexibility and function of an alpha-actinin similar to the ancestral alpha-actinin.,Pinotsis N, Zielinska K, Babuta M, Arolas JL, Kostan J, Khan MB, Schreiner C, Salmazo A, Ciccarelli L, Puchinger M, Gkougkoulia EA, Ribeiro EA Jr, Marlovits TC, Bhattacharya A, Djinovic-Carugo K Proc Natl Acad Sci U S A. 2020 Sep 8;117(36):22101-22112. doi:, 10.1073/pnas.1917269117. Epub 2020 Aug 26. PMID:32848067<ref>PMID:32848067</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 6sl2" style="background-color:#fffaf0;"></div>
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Enthi]]
[[Category: Large Structures]]
[[Category: Djinovic-Carugo, K]]
[[Category: Khan, M B]]
[[Category: Pinotsis, N]]
[[Category: Actin binding domain]]
[[Category: Actinin]]
[[Category: Calcium regulation]]
[[Category: Calmodulin-like domain]]
[[Category: Spectrin repear]]
[[Category: Structural protein]]