5DS2

Core domain of the class I small heat-shock protein HSP 18.1 from Pisum sativum

Summary for 5DS2

• Entry DOI: 10.2210/pdb5ds2/pdb
• Descriptor: 18.1 kDa class I heat shock protein, SULFATE ION (3 entities in total)
• Functional Keywords: chaperone, small heat-shock protein, stress
• Biological source: Pisum sativum (Garden pea)
• Total number of polymer chains: 6
• Total formula weight: 67629.88

Authors

Shepherd, D.A.,Laganowsky, A.,Allison, T.M.,Hochberg, G.K.A.,Benesch, J.L.P. (deposition date: 2015-09-16, release date: 2016-09-28, Last modification date: 2024-01-10)

Primary citation

Hochberg, G.K.A.,Shepherd, D.A.,Marklund, E.G.,Santhanagoplan, I.,Degiacomi, M.T.,Laganowsky, A.,Allison, T.M.,Basha, E.,Marty, M.T.,Galpin, M.R.,Struwe, W.B.,Baldwin, A.J.,Vierling, E.,Benesch, J.L.P.
Structural principles that enable oligomeric small heat-shock protein paralogs to evolve distinct functions.
Science, 359:930-935, 2018

PubMed Abstract: Oligomeric proteins assemble with exceptional selectivity, even in the presence of closely related proteins, to perform their cellular roles. We show that most proteins related by gene duplication of an oligomeric ancestor have evolved to avoid hetero-oligomerization and that this correlates with their acquisition of distinct functions. We report how coassembly is avoided by two oligomeric small heat-shock protein paralogs. A hierarchy of assembly, involving intermediates that are populated only fleetingly at equilibrium, ensures selective oligomerization. Conformational flexibility at noninterfacial regions in the monomers prevents coassembly, allowing interfaces to remain largely conserved. Homomeric oligomers must overcome the entropic benefit of coassembly and, accordingly, homomeric paralogs comprise fewer subunits than homomers that have no paralogs.

PubMed: 29472485
DOI: 10.1126/science.aam7229

Experimental method

X-RAY DIFFRACTION (1.85 Å)