4YE0

Stress-induced protein 1 truncation mutant (43 - 140) from Caenorhabditis elegans

Summary for 4YE0

• Entry DOI: 10.2210/pdb4ye0/pdb
• Related: 2WJ7
• Descriptor: Stress-induced protein 1, SULFATE ION (3 entities in total)
• Functional Keywords: molecular chaperon, shsp, heat shock, protein aggregation, chaperone
• Biological source: Caenorhabditis elegans
• Total number of polymer chains: 2
• Total formula weight: 26251.49

Authors

Fleckenstein, T.,Kastenmueller, A.,Stein, M.L.,Peters, C.,Daake, M.,Krause, M.,Weinfurtner, D.,Haslbeck, M.,Weinkauf, S.,Groll, M.,Buchner, J. (deposition date: 2015-02-23, release date: 2015-06-10, Last modification date: 2024-05-08)

Primary citation

Fleckenstein, T.,Kastenmuller, A.,Stein, M.L.,Peters, C.,Daake, M.,Krause, M.,Weinfurtner, D.,Haslbeck, M.,Weinkauf, S.,Groll, M.,Buchner, J.
The Chaperone Activity of the Developmental Small Heat Shock Protein Sip1 Is Regulated by pH-Dependent Conformational Changes.
Mol.Cell, 58:1067-1078, 2015

PubMed Abstract: Small heat shock proteins (sHsps) are ubiquitous molecular chaperones that prevent the aggregation of unfolding proteins during proteotoxic stress. In Caenorhabditis elegans, Sip1 is the only sHsp exclusively expressed in oocytes and embryos. Here, we demonstrate that Sip1 is essential for heat shock survival of reproducing adults and embryos. X-ray crystallography and electron microscopy revealed that Sip1 exists in a range of well-defined globular assemblies consisting of two half-spheres, each made of dimeric "spokes." Strikingly, the oligomeric distribution of Sip1 as well as its chaperone activity depend on pH, with a trend toward smaller species and higher activity at acidic conditions such as present in nematode eggs. The analysis of the interactome shows that Sip1 has a specific substrate spectrum including proteins that are essential for embryo development.

PubMed: 26009280
DOI: 10.1016/j.molcel.2015.04.019

Experimental method

X-RAY DIFFRACTION (2.1 Å)