3tu5: Difference between revisions

<StructureSection load='3tu5' size='340' side='right' caption='[[3tu5]], [[Resolution|resolution]] 3.00&Aring;' scene=''>

<table><tr><td colspan='2'>[[3tu5]] is a 2 chain structure with sequence from [http://en.wikipedia.org/wiki/ ] and [http://en.wikipedia.org/wiki/Oryctolagus_cuniculus Oryctolagus cuniculus]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=3TU5 OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=3TU5 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=CA:CALCIUM+ION'>CA</scene>, <scene name='pdbligand=MPD:(4S)-2-METHYL-2,4-PENTANEDIOL'>MPD</scene></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=3tu5 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=3tu5 OCA], [http://pdbe.org/3tu5 PDBe], [http://www.rcsb.org/pdb/explore.do?structureId=3tu5 RCSB], [http://www.ebi.ac.uk/pdbsum/3tu5 PDBsum], [http://prosat.h-its.org/prosat/prosatexe?pdbcode=3tu5 ProSAT]</span></td></tr>

[[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/GELS_HUMAN GELS_HUMAN]] Calcium-regulated, actin-modulating protein that binds to the plus (or barbed) ends of actin monomers or filaments, preventing monomer exchange (end-blocking or capping). It can promote the assembly of monomers into filaments (nucleation) as well as sever filaments already formed. Plays a role in ciliogenesis.<ref>PMID:20393563</ref> 

Conformational changes induced by ATP hydrolysis on actin are involved in the regulation of complex actin networks. Previous structural and biochemical data implicate the DNase I binding loop (D-loop) of actin in such nucleotide-dependent changes. Here, we investigated the structural and conformational states of the D-loop (in solution) using cysteine scanning mutagenesis and site-directed labeling. The reactivity of D-loop cysteine mutants toward acrylodan and the mobility of spin labels on these mutants do not show patterns of an alpha-helical structure in monomeric and filamentous actin, irrespective of the bound nucleotide. Upon transition from monomeric to filamentous actin, acrylodan emission spectra and electron paramagnetic resonance line shapes of labeled mutants are blue-shifted and more immobilized, respectively, with the central residues (residues 43-47) showing the most drastic changes. Moreover, complex electron paramagnetic resonance line shapes of spin-labeled mutants suggest several conformational states of the D-loop. Together with a new (to our knowledge) actin crystal structure that reveals the D-loop in a unique hairpin conformation, our data suggest that the D-loop equilibrates in F-actin among different conformational states irrespective of the nucleotide state of actin.

 

== References ==

[[Category: Durer, Z A.O]]

[[Category: Kudryashov, D S]]

[[Category: Sawaya, M R]]

[[Category: Unusual hairpin conformation in the d-loop]]