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2b26
From Proteopedia
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| , resolution 3.2Å | |||||||
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| Gene: | SIS1 (Saccharomyces cerevisiae), Hsc70-2, Hsc2 (Drosophila melanogaster) | ||||||
| Coordinates: | save as pdb, mmCIF, xml | ||||||
The crystal structure of the protein complex of yeast Hsp40 Sis1 and Hsp70 Ssa1
Overview
Heat shock protein (Hsp) 40 facilitates the critical role of Hsp70 in a number of cellular processes such as protein folding, assembly, degradation and translocation in vivo. Hsp40 and Hsp70 stay in close contact to achieve these diverse functions. The conserved C-terminal EEVD motif in Hsp70 has been shown to regulate Hsp40-Hsp70 interaction by an unknown mechanism. Here, we provide a structural basis for this regulation by determining the crystal structure of yeast Hsp40 Sis1 peptide-binding fragment complexed with the Hsp70 Ssa1 C-terminal. The Ssa1 extreme C-terminal eight residues, G634PTVEEVD641, form a beta-strand with the domain I of Sis1 peptide-binding fragment. Surprisingly, the Ssa1 C-terminal binds Sis1 at the site where Sis1 interacts with the non-native polypeptides. The negatively charged residues within the EEVD motif in Ssa1 C-terminal form extensive charge-charge interactions with the positively charged residues in Sis1. The structure-based mutagenesis data support the structural observations.
About this Structure
2B26 is a Protein complex structure of sequences from Drosophila melanogaster and Saccharomyces cerevisiae. Full crystallographic information is available from OCA.
Reference
Crystal structure of yeast Sis1 peptide-binding fragment and Hsp70 Ssa1 C-terminal complex., Li J, Wu Y, Qian X, Sha B, Biochem J. 2006 Sep 15;398(3):353-60. PMID:16737444
Page seeded by OCA on Thu Mar 20 15:56:42 2008
