Subcellular Localization/Activity Cytosol/assists folding of nascent chains; catalyzes peptidyl-prolyl isomerization in vitro. Cytosol/assists folding of nascent chains; catalyzes peptidyl-prolyl folding/quality control? in protein Cytosol/interacts with ribosomes, SRP and translating polypeptide chains; role Cytosol/interacts with Ssb; folding of nascent chains on ribosomes? folding in vivo of promotes during heat stress; subset; stabilizes proteins Cytosol/folding of a cytosolic protein in vitro. of many proteins refolding proteins; overproduced species that has GroEL. the only archaeal Cytosol/folding of cytosolic proteins; and prevents mitochondrial proteins binds to heat-denatured Mitochondria/folding of newly imported proteins; aggregation. Mitochondria/folding of newly imported proteins. e.g., ribulose bisphosphate carboxylase. proteins, and assembly of chloroplast Chloroplast/folding of unfolded polypeptides in vitro. subset; refolding folding of a protein promotes Cytosol/stress-inducible, of downstream subset, including actin, tubulins, and WD40 domain proteins; Cytosol/folding of a cytosolic protein into nontoxic oligomers. in de novo folding; assembly of polyglutamine expansion proteins unfolding and proteolysis. in ATP-dependent Cytosol/works with ClpP protease with DnaK. disaggregation protein Cytosol/ATP-dependent establishes and maintains the [PSI] yeast prion phenotype. heat-damaged proteins; Cytosol/reactivates degradation and turnover aggregation; of unassembled mitochondrial proteins. Mitochondria/prevents proteolysis. to promote with the ClpP protease Chloroplast/works associates with inclusion bodies; works DnaK in protein aggregation; protein heat-denatured Cytosol/prevents refolding. aggregation. Cytosol/stabilizes unfolded polypeptides and prevents for efficient non-native dissociation required temperature-dependent aggregation; of protein Cytosol/prevention substrate binding. aggregation. protein heat-denatured Cytosol/in the vertebrate eye lens; prevents of thermally unfolded and oxidatively damaged aggregation prevents molecular ; Cytosol/redox-regulated proteins. in an unfolded state for export. proteins Cytosol/stabilizes some secretory maintains solubility of folding intermediates in the periplasm. Periplasm/interacts with outer membrane proteins, pathway. Periplasm/P Pili assembly in the chaperone-usher pathway. 1 Pili assembly in the chaperone-usher Periplasm/Type interacts with some non-native proteins ER membrane/works with glycosyltransferase to fold glycosylated proteins; independent of glycosylation. ER lumen/similar to calnexin. in the collagen biosynthetic pathway. ER/binds to collagen; chaperone Cochaperone/Cofactor SRP Ssb GroES GroES Hsp10 Hsp10 Cpn10, Cpn21 Prefoldin/GimC PhLP Prefoldin/GimC, SspB ClpP, DnaK, DnaJ, GrpE Hsp70, Hsp40 Ssc1, Pim1 ClpP SecA PapC FimD ERp57, EDEM ERp57, EDEM P4H Monomer (kDa)/Oligomeric State 48/dimer 19, 17/heterodimer 58, 49/heterodimer 57/14mer 58/14mer ~60/14mer ~60/14mer 14mer 57,58/Hetero 16mer 58/Hetero 57–60/Hetero 16mer 83/hexamer 96/hexamer 104/hexamer 85 100 16/A: monomer; B: dimer/multimer 16.5 24/24mer 32mer 33/dimer (active form) 17/tetramer 17/trimer 27/monomer 23/monomer 90/monomer 60/monomer 47 )

) θ α β - α ) and β α , α )/1A6D Bank ID β Chaperone/ Protein Data Protein - Trigger factor/ Trigger 1W2B; 2AAR NAC ( RAC (Ssz1, Zuotin) GroEL/1AON GroEL Hsp60 mtHsp60 Cpn60 ( Thermosome ( and TRiC/CCT ( ClpA ClpB/1QVR Hsp104 Hsp78 ClpC IbpA, IbpB Hsp16.5/1SHS Hsp26/2H50 α Hsp33/1VZY SecB/1QYN Skp/1SG2 PapD/3DPA FimC/1BF8 Calnexin/1JHN Calreticulin Hsp47 / Organism E. coli S. cerevisiae E. coli Methanosarcinae S. cerevisiae Mammals A. thaliana acidophilum T. S. cerevisiae Mammals E. coli S. cerevisiae Plants E. coli M. jannashii S. cerevisiae Mammals E. coli Mammals

Kingdom

Eubacteria Eukaryotes Eubacteria Archaea Eukaryotes Archaea Eukaryotes Eubacteria Eukaryotes Eubacteria Archaea Eukaryotes Eubacteria Eukaryotes

Chaperones (sHsp) Group I Group II Group

Associated Associated Hsp100 Proteins Shock Chaperones Other

Chaperonins Ribosome- Heat Small SnapShot: Molecular Chaperones, Part II Part Chaperones, SnapShot:Molecular Ulrich Hartl Hung-Chun Chang, Manajit Hayer-Hartl, and F. Tang, Yun-Chi Martinsried, Germany Max Planck Institute of Biochemistry, Department of Cellular Biochemistry, See online version for references.

412 Cell 128, January 26, 2007 ©2007 Elsevier Inc. DOI 10.1016/j.cell.2007.01.013 SnapShot: Molecular Chaperones, Part II Yun-Chi Tang, Hung-Chun Chang, Manajit Hayer-Hartl, and F. Ulrich Hartl Department of Cellular Biochemistry, Max Planck Institute of Biochemistry, Martinsried, Germany

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412.e1 Cell 128, January 26, 2007 ©2007 Elsevier Inc. DOI 10.1016/j.cell.2007.01.013