2QXL

Crystal Structure Analysis of Sse1, a yeast Hsp110

Summary for 2QXL

• Entry DOI: 10.2210/pdb2qxl/pdb
• Descriptor: Heat shock protein homolog SSE1, MAGNESIUM ION, POTASSIUM ION, ... (5 entities in total)
• Functional Keywords: hsp110, hsp70, molecular chaperone, atp state, atp-binding, calmodulin-binding, nucleotide-binding, phosphorylation, stress response, chaperone
• Biological source: Saccharomyces cerevisiae (baker's yeast)
• Cellular location: Cytoplasm : P32589
• Total number of polymer chains: 2
• Total formula weight: 148272.89

Authors

Hendrickson, W.A.,Liu, Q. (deposition date: 2007-08-12, release date: 2007-10-23, Last modification date: 2024-02-21)

Primary citation

Liu, Q.,Hendrickson, W.A.
Insights into hsp70 chaperone activity from a crystal structure of the yeast hsp110 Sse1.
Cell(Cambridge,Mass.), 131:106-120, 2007

PubMed Abstract: Classic Hsp70 chaperones assist in diverse processes of protein folding and translocation, and Hsp110s had seemed by sequence to be distant relatives within an Hsp70 superfamily. The 2.4 A resolution structure of Sse1 with ATP shows that Hsp110s are indeed Hsp70 relatives, and it provides insight into allosteric coupling between sites for ATP and polypeptide-substrate binding in Hsp70s. Subdomain structures are similar in intact Sse1(ATP) and in the separate Hsp70 domains, but conformational dispositions are radically different. Interfaces between Sse1 domains are extensive, intimate, and conservative in sequence with Hsp70s. We propose that Sse1(ATP) may be an evolutionary vestige of the Hsp70(ATP) state, and an analysis of 64 mutant variants in Sse1 and three Hsp70 homologs supports this hypothesis. An atomic-level understanding of Hsp70 communication between ATP and substrate-binding domains follows. Requirements on Sse1 for yeast viability are in keeping with the distinct function of Hsp110s as nucleotide exchange factors.

PubMed: 17923091
DOI: 10.1016/j.cell.2007.08.039

Experimental method

X-RAY DIFFRACTION (2.41 Å)