View source for 2bol

[[Image:2bol.gif|left|200px]]<br /><applet load="2bol" size="350" color="white" frame="true" align="right" spinBox="true" 
caption="2bol, resolution 2.50&Aring;" />
'''CRYSTAL STRUCTURE AND ASSEMBLY OF TSP36, A METAZOAN SMALL HEAT SHOCK PROTEIN'''<br />

==Overview==
Small heat shock proteins (sHsps) are oligomers that perform a protective, function by binding denatured proteins. Although ubiquitous, they are of, variable sequence except for a C-terminal approximately 90-residue, "alpha-crystallin domain". Unlike larger stress response chaperones, sHsps, are ATP-independent and generally form polydisperse assemblies. One, proposed mechanism of action involves these assemblies breaking into, smaller subunits in response to stress, before binding unfolding substrate, and reforming into larger complexes. Two previously solved non-metazoan, sHsp multimers are built from dimers formed by domain swapping between the, alpha-crystallin domains, adding to evidence that the smaller subunits are, dimers. Here, the 2.5A resolution structure of an sHsp from the parasitic, flatworm Taenia saginata Tsp36, the first metazoan crystal structure, shows a new mode of dimerization involving N-terminal regions, which, differs from that seen for non-metazoan sHsps. Sequence differences in the, alpha-crystallin domains between metazoans and non-metazoans are critical, to the different mechanism of dimerization, suggesting that some, structural features seen for Tsp36 may be generalized to other metazoan, sHsps. The structure also indicates scope for flexible assembly of, subunits, supporting the proposed process of oligomer breakdown, substrate, binding and reassembly as the chaperone mechanism. It further shows how, sHsps can bind coil and secondary structural elements by wrapping them, around the alpha-crystallin domain. The structure also illustrates, possible roles for conserved residues associated with disease, and, suggests a mechanism for the sHsp-related pathogenicity of some flatworm, infections. Tsp36, like other flatworm sHsps, possesses two divergent sHsp, repeats per monomer. Together with the two previously solved structures, a, total of four alpha-crystallin domain structures are now available, giving, a better definition of domain boundaries for sHsps.

==About this Structure==
2BOL is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Taenia_saginata Taenia saginata] with <scene name='pdbligand=SO4:'>SO4</scene> as [http://en.wikipedia.org/wiki/ligand ligand]. Known structural/functional Site: <scene name='pdbsite=AC1:So4+Binding+Site+For+Chain+A'>AC1</scene>. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2BOL OCA]. 

==Reference==
Wrapping the alpha-crystallin domain fold in a chaperone assembly., Stamler R, Kappe G, Boelens W, Slingsby C, J Mol Biol. 2005 Oct 14;353(1):68-79. PMID:[http://ispc.weizmann.ac.il//pmbin/getpm?pmid=16165157 16165157]
[[Category: Single protein]]
[[Category: Taenia saginata]]
[[Category: Boelens, W.C.]]
[[Category: Kappe, G.]]
[[Category: Slingsby, C.]]
[[Category: Stamler, R.J.]]
[[Category: SO4]]
[[Category: a-crystallin]]
[[Category: molecular chaperone]]
[[Category: small heat shock protein]]
[[Category: taenia saginata]]

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