View source for 4b1x


==Structure of the Phactr1 RPEL-2 bound to G-actin==
<StructureSection load='4b1x' size='340' side='right' caption='[[4b1x]], [[Resolution|resolution]] 1.80&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[4b1x]] is a 2 chain structure with sequence from [http://en.wikipedia.org/wiki/Oryctolagus_cuniculus Oryctolagus cuniculus]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=4B1X OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=4B1X FirstGlance]. <br>
</td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat"><scene name='pdbligand=ATP:ADENOSINE-5-TRIPHOSPHATE'>ATP</scene>, <scene name='pdbligand=LAB:LATRUNCULIN+B'>LAB</scene>, <scene name='pdbligand=MG:MAGNESIUM+ION'>MG</scene></td></tr>
<tr id='related'><td class="sblockLbl"><b>[[Related_structure|Related:]]</b></td><td class="sblockDat">[[1alm|1alm]], [[1atn|1atn]], [[1eqy|1eqy]], [[1esv|1esv]], [[1h1v|1h1v]], [[1ijj|1ijj]], [[1j6z|1j6z]], [[1kxp|1kxp]], [[1lcu|1lcu]], [[1lot|1lot]], [[1m8q|1m8q]], [[1ma9|1ma9]], [[1mvw|1mvw]], [[1nwk|1nwk]], [[1o18|1o18]], [[1o19|1o19]], [[1o1a|1o1a]], [[1o1b|1o1b]], [[1o1c|1o1c]], [[1o1d|1o1d]], [[1o1e|1o1e]], [[1o1f|1o1f]], [[1o1g|1o1g]], [[1p8z|1p8z]], [[1qz5|1qz5]], [[1qz6|1qz6]], [[1rdw|1rdw]], [[1rfq|1rfq]], [[1rgi|1rgi]], [[1s22|1s22]], [[1sqk|1sqk]], [[1t44|1t44]], [[1uy5|1uy5]], [[1wua|1wua]], [[1y64|1y64]], [[2a3z|2a3z]], [[2a40|2a40]], [[2a41|2a41]], [[2a42|2a42]], [[2a5x|2a5x]], [[2asm|2asm]], [[2aso|2aso]], [[2asp|2asp]], [[2d1k|2d1k]], [[2ff3|2ff3]], [[2ff6|2ff6]], [[2fxu|2fxu]], [[2v51|2v51]], [[2v52|2v52]], [[2vcp|2vcp]], [[2vyp|2vyp]], [[2w49|2w49]], [[2w4u|2w4u]], [[2y83|2y83]], [[2yje|2yje]], [[2yjf|2yjf]], [[4a7h|4a7h]], [[4a7l|4a7l]], [[4a7n|4a7n]], [[4b1u|4b1u]], [[4b1v|4b1v]], [[4b1w|4b1w]], [[4b1y|4b1y]], [[4b1z|4b1z]]</td></tr>
<tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=4b1x FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=4b1x OCA], [http://pdbe.org/4b1x PDBe], [http://www.rcsb.org/pdb/explore.do?structureId=4b1x RCSB], [http://www.ebi.ac.uk/pdbsum/4b1x PDBsum], [http://prosat.h-its.org/prosat/prosatexe?pdbcode=4b1x ProSAT]</span></td></tr>
</table>
== Function ==
[[http://www.uniprot.org/uniprot/ACTS_RABIT ACTS_RABIT]] Actins are highly conserved proteins that are involved in various types of cell motility and are ubiquitously expressed in all eukaryotic cells. [[http://www.uniprot.org/uniprot/PHAR1_MOUSE PHAR1_MOUSE]] Binds actin monomers (G actin) and plays a role in the reorganization of the actin cytoskeleton and in formation of actin stress fibers. Plays a role in the formation of tubules by endothelial cells. Regulates PPP1CA activity. Required for normal cell survival (By similarity). Plays a role in cell motility.<ref>PMID:22976292</ref> <ref>PMID:23041370</ref>  
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
The Phactr family of PP1-binding proteins and the myocardin-related transcription factor family of transcriptional coactivators contain regulatory domains comprising three copies of the RPEL motif, a G-actin binding element. We report the structure of a Phactr1 G-actinRPEL domain complex. Three G-actins surround the crank-shaped RPEL domain forming a closed helical assembly. Their spatial relationship is identical to the RPEL-actins within the pentavalent MRTF G-actinRPEL domain complex, suggesting that conserved cooperative interactions between actinRPEL units organize the assembly. In the trivalent Phactr1 complex, each G-actinRPEL unit makes secondary contacts with its downstream actin involving distinct RPEL residues. Similar secondary contacts are seen in G-actinRPEL peptide crystals. Loss-of-secondary-contact mutations destabilize the Phactr1 G-actinRPEL assembly. Furthermore, actin-mediated inhibition of Phactr1 nuclear import requires secondary contact residues in the Phactr1 N-terminal RPEL-N motif, suggesting that it involves interaction of RPEL-N with the C-terminal assembly. Secondary actin contacts by actin-bound RPEL motifs thus govern formation of multivalent actinRPEL assemblies.

Structures of the Phactr1 RPEL Domain and RPEL Motif Complexes with G-Actin Reveal the Molecular Basis for Actin Binding Cooperativity.,Mouilleron S, Wiezlak M, O'Reilly N, Treisman R, McDonald NQ Structure. 2012 Oct 2. pii: S0969-2126(12)00335-8. doi:, 10.1016/j.str.2012.08.031. PMID:23041370<ref>PMID:23041370</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 4b1x" style="background-color:#fffaf0;"></div>
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Oryctolagus cuniculus]]
[[Category: McDonald, N Q]]
[[Category: Mouilleron, S]]
[[Category: Reilly, N O]]
[[Category: Treisman, R]]
[[Category: Wiezlak, M]]
[[Category: Atp-binding]]
[[Category: Cytoskeleton]]
[[Category: Muscle protein]]
[[Category: Nucleotide-binding]]
[[Category: Structural protein]]
[[Category: Transcription]]
[[Category: Transcription regulation]]