View source for 6kwz


==Crystal structure of fragmin F3 domain with calcium ion==
<StructureSection load='6kwz' size='340' side='right'caption='[[6kwz]], [[Resolution|resolution]] 1.55&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[6kwz]] is a 2 chain structure with sequence from [https://en.wikipedia.org/wiki/Physarum_polycephalum Physarum polycephalum]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=6KWZ OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=6KWZ 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]] 1.551&#8491;</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></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=6kwz FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=6kwz OCA], [https://pdbe.org/6kwz PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=6kwz RCSB], [https://www.ebi.ac.uk/pdbsum/6kwz PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=6kwz ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/Q94707_PHYPO Q94707_PHYPO] 
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
Gelsolin superfamily proteins, consisting of multiple domains (usually six), sever actin filaments and cap the barbed ends in a Ca(2+)-dependent manner. Two types of evolutionally conserved Ca(2+)-binding sites have been identified in this family; type-1 (between gelsolin and actin) and type-2 (within the gelsolin domain). Fragmin, a member in the slime mold Physarum polycephalum, consists of three domains (F1-F3) that are highly similar to the N-terminal half of mammalian gelsolin (G1-G3). Despite their similarities, the two proteins exhibit a significant difference in the Ca(2+) dependency; F1-F3 absolutely requires Ca(2+) for the filament severing whereas G1-G3 does not. In this study, we examined the strong dependency of fragmin on Ca(2+) using biochemical and structural approaches. Our co-sedimentation assay demonstrated that Ca(2+) significantly enhanced the binding of F2-F3 to actin. We determined the crystal structure of F2-F3 in the presence of Ca(2+). F2-F3 binds a total of three calcium ions; while two are located in type-2 sites within F2 or F3, the remaining one resides between the F2 long helix and the F3 short helix. The inter-domain Ca(2+)-coordination appears to stabilize F2-F3 in a closely packed configuration. Notably, the F3 long helix exhibits a bent conformation which is different from the straight G3 long helix in the presence of Ca(2+). Our results provide the first structural evidence for the existence of an unconventional Ca(2+)-binding site in the gelsolin superfamily proteins.

Novel inter-domain Ca(2+)-binding site in the gelsolin superfamily protein fragmin.,Takeda S, Fujiwara I, Sugimoto Y, Oda T, Narita A, Maeda Y J Muscle Res Cell Motil. 2019 Dec 20. pii: 10.1007/s10974-019-09571-5. doi:, 10.1007/s10974-019-09571-5. PMID:31863323<ref>PMID:31863323</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 6kwz" style="background-color:#fffaf0;"></div>
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Large Structures]]
[[Category: Physarum polycephalum]]
[[Category: Takeda S]]