2z5h: Difference between revisions
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==Crystal structure of the head-to-tail junction of tropomyosin complexed with a fragment of TnT== | |||
<StructureSection load='2z5h' size='340' side='right' caption='[[2z5h]], [[Resolution|resolution]] 2.89Å' scene=''> | |||
== Structural highlights == | |||
<table><tr><td colspan='2'>[[2z5h]] is a 10 chain structure with sequence from [http://en.wikipedia.org/wiki/Gallus_gallus Gallus gallus], [http://en.wikipedia.org/wiki/Oryctolagus_cuniculus Oryctolagus cuniculus] and [http://en.wikipedia.org/wiki/Saccharomyces_cerevisiae Saccharomyces cerevisiae]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2Z5H OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=2Z5H FirstGlance]. <br> | |||
</td></tr><tr><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=2z5h FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=2z5h OCA], [http://www.rcsb.org/pdb/explore.do?structureId=2z5h RCSB], [http://www.ebi.ac.uk/pdbsum/2z5h PDBsum]</span></td></tr> | |||
<table> | |||
== Evolutionary Conservation == | |||
[[Image:Consurf_key_small.gif|200px|right]] | |||
Check<jmol> | |||
<jmolCheckbox> | |||
<scriptWhenChecked>select protein; define ~consurf_to_do selected; consurf_initial_scene = true; script "/wiki/ConSurf/z5/2z5h_consurf.spt"</scriptWhenChecked> | |||
<scriptWhenUnchecked>script /wiki/extensions/Proteopedia/spt/initialview01.spt</scriptWhenUnchecked> | |||
<text>to colour the structure by Evolutionary Conservation</text> | |||
</jmolCheckbox> | |||
</jmol>, as determined by [http://consurfdb.tau.ac.il/ ConSurfDB]. You may read the [[Conservation%2C_Evolutionary|explanation]] of the method and the full data available from [http://bental.tau.ac.il/new_ConSurfDB/chain_selection.php?pdb_ID=2ata ConSurf]. | |||
<div style="clear:both"></div> | |||
<div style="background-color:#fffaf0;"> | |||
== Publication Abstract from PubMed == | |||
Head-to-tail polymerization of tropomyosin is crucial for its actin binding, function in actin filament assembly, and the regulation of actin-myosin contraction. Here, we describe the 2.1 A resolution structure of crystals containing overlapping tropomyosin N and C termini (TM-N and TM-C) and the 2.9 A resolution structure of crystals containing TM-N and TM-C together with a fragment of troponin-T (TnT). At each junction, the N-terminal helices of TM-N were splayed, with only one of them packing against TM-C. In the C-terminal region of TM-C, a crucial water in the coiled-coil core broke the local 2-fold symmetry and helps generate a kink on one helix. In the presence of a TnT fragment, the asymmetry in TM-C facilitates formation of a 4-helix bundle containing two TM-C chains and one chain each of TM-N and TnT. Mutating the residues that generate the asymmetry in TM-C caused a marked decrease in the affinity of troponin for actin-tropomyosin filaments. The highly conserved region of TnT, in which most cardiomyopathy mutations reside, is crucial for interacting with tropomyosin. The structure of the ternary complex also explains why the skeletal- and cardiac-muscle specific C-terminal region is required to bind TnT and why tropomyosin homodimers bind only a single TnT. On actin filaments, the head-to-tail junction can function as a molecular swivel to accommodate irregularities in the coiled-coil path between successive tropomyosins enabling each to interact equivalently with the actin helix. | |||
Structural basis for tropomyosin overlap in thin (actin) filaments and the generation of a molecular swivel by troponin-T.,Murakami K, Stewart M, Nozawa K, Tomii K, Kudou N, Igarashi N, Shirakihara Y, Wakatsuki S, Yasunaga T, Wakabayashi T Proc Natl Acad Sci U S A. 2008 May 20;105(20):7200-5. Epub 2008 May 15. PMID:18483193<ref>PMID:18483193</ref> | |||
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.<br> | |||
</div> | |||
==See Also== | ==See Also== | ||
*[[Gcn4|Gcn4]] | |||
*[[Tropomyosin|Tropomyosin]] | *[[Tropomyosin|Tropomyosin]] | ||
*[[Troponin|Troponin]] | *[[Troponin|Troponin]] | ||
== References == | |||
== | <references/> | ||
__TOC__ | |||
</StructureSection> | |||
[[Category: Gallus gallus]] | [[Category: Gallus gallus]] | ||
[[Category: Oryctolagus cuniculus]] | [[Category: Oryctolagus cuniculus]] |