Snapshot: Molecular Chaperones, Part I Part Chaperones, Snapshot:Molecular Ulrich Hartl Manajit Hayer-Hartl, and F

Sse1/2. Ssz1. S. cerevisiae S. cerevisiae Subcellular Localization/Activity Ssc1. homolog; folding and regulation of steroid hormone receptors and many kinases. hormone receptors of steroid homolog; folding and regulation S. cerevisiae S. cerevisiae Cytosol/folding of nascent chains on ribosomes; similar to response. protein unfolded regulates subunits; protein ER unassembled/misfolded to binds ER; into translocation ER/protein ER/Hsp110 homolog; nucleotide exchange factor of Kar2. assembly. ER/similar to Kar2; multimeric ER protein translocation and folding in mitochondria. Mitochondria/protein complex assembly; mediates folding of imported proteins? Mitochondria/assists some mitochondrial protein complex assembly; Fe/S cluster insertion. Mitochondria/protein Mitochondria/similar to into thylakoid membrane. insertion of light-harvesting complex protein of imported proteins; Chloroplast/folding hydrophobic DnaK to nascent chains; recognizes by DnaK; recruits hydrolysis Cytosol/binds to and accelerates ATP peptide segments in unfolded proteins. membranes. transport across by Ssa; protein hydrolysis Cytosol/interacts with non-native polypeptides triggering ATP recruits Hsc70 to cycle; efficient loading of peptide substrate onto Hsc70. Auxilin of Hsc70 ATPase Cytosol/regulation vesicle uncoating. clathrin-coated vesicles and promotes for Kar2. folding in ER lumen; acts as a J protein protein ER lumen/regulates ER membrane/SRP-independent posttranslational translocation into ER; works with Sec61 complex and Kar2. Mitochondria/mitochondrial biogenesis and folding of newly imported proteins. cells. in stressed refolding Cytosol/protein a capacitor proteins; of stress-denatured reactivation of signaling proteins; Cytosol/folding and conformational regulation of phenotypic variation. Cytosol/similar to Cytosol/cytokinin signalling and plant development. proteins. ER/folding and assembly of some secretory ER/function unknown; similar to Grp94? Chloroplast/unknown Cytosol/folding of nascent proteins; export of some proteins; reactivates heat-inactivated proteins; facilitates abnormal heat-inactivated proteins; reactivates export of some proteins; Cytosol/folding of nascent proteins; heat-shock response. disassembly; regulates aggregate degradation; works with ClpB in protein protein Cytosol/similar to bacterial DnaK. transport into ER, mitochondria. protein Cytosol/folding of newly synthesized proteins; Cytosol/folding of ribosome-bound nascent chains. Cytosol/Zuotin cofactor; modifies Zuotin-Ssb interaction; folding of nascent chains on ribosomes. folding and refolding. Cytosol/nucleotide exchange factor for Ssa and Ssb Hsp70s; participates in protein lysosomal transport into ER, mitochondria, nucleus; promotes Cytosol/mediates nascent polypeptide folding; protein inhibits polyglutamine fibril formation. degradation of cytosolic proteins; similar to under stress; aggregation protein Cytosol/prevents Cochaperone/Cofactor DnaJ, GrpE, ClpB DnaJ, GrpE Ydj1, Sis1, Sti1, Snl1, Fes1, Sse1/2, Cns1 Zuotin, Sse1/2, Ssz1 Zuotin Ssa1, Ssb1, Sis1 SGT, Hsp40, Hop, Bag1-5, Hip, HspBP1, CHIP, Hsp110 homologs TPR1, Tom70, Hsp70 MPP11 Sec63, Scj1, Jem1, Lhs1, Sil1/Sls1 Kar2 Grp170, Sil1/Sls1 Tim14, Tim16, Tim44, Mdj1, Mge1 Mge1 Jac1, Mge1 DnaK, GrpE Ssa Hsp70, Hip Kar2 Kar2 Ssc1, Tim14, Tim 16 Sti1, Aha1, cdc37, p23/Sba1, Ppt1, CPR6 Sgt1, TPR2, Hop, Hip, Hsp70, p50, p23, CHIP, FKBP52) FKBP51, FKBP38, (Cyp40, Immunophilins Hop, Sgt1, Immunophilin Grp78 Monomer (kDa)/ Monomer 55/heterodimer 74/monomer 97 72/monomer 71/monomer 70/monomer 72/monomer 74/monomer 68/monomer 41/dimer 45, 38/dimer 39, 38, 100 35 75 49 71/dimer 81/dimer 85/dimer 81 86/dimer 94 88 Oligomeric State Oligomeric 69/monomer 67/monomer 70/monomer 66/monomer 58/heterodimer 77/monomer; heterodimer 71/monomer 97/monomer Data Bank ID Chaperone/Protein Chaperone/Protein DnaK/1DKG; 1DKZ DnaK Ssa1-4 Ssb1,2 Pdr13p/Ssz1 Sse1/2 Hsc70, Hsp70/1YUW Hsp110 Hsp70L1 Kar2 Lhs1 Bip/Grp78 Ssc1 Ssc3/Ecm10 Ssq1 mtHsp70 ctHsp70 DnaJ/1EXK Ydj1,Sis1/1NLT Hdj1 (Hsp40), Hdj2, Auxilin Scj1 Sec63 Mdj1 HtpG/1Y4U; 1SF8 Hsp82/2CGE; 1US7 Hsp90 (Hsp83, Hsp89) AtHsp90-1,2,3,4 Grp94 (ERp99) AtHsp90-7 AtHsp90-5 Organism S. cerevisiae Mammals S. cerevisiae Mammals E. coli S. cerevisiae Mammals S. cerevisiae E. coli S. cerevisiae Mammals A. thaliana Mammals A. thaliana E. coli Methanosarcinae S. cerevisiae Mammals

Kingdom Eubacteria Eukaryotes Eubacteria Eukaryotes Eubacteria Archaea Eukaryotes

Hsp40 Hsp90 Hsp70 System Hsp70 SnapShot: Molecular Chaperones, Part I Part Chaperones, SnapShot:Molecular Ulrich Hartl Manajit Hayer-Hartl, and F. Tang, Hung-Chun Chang, Yun-Chi Martinsried, Germany Max Planck Institute of Biochemistry, Department of Cellular Biochemistry, See online version for references.

212 Cell 128, January 12, 2007 ©2007 Elsevier Inc. DOI 10.1016/j.cell.2007.01.001 SnapShot: Molecular Chaperones, Part I Hung-Chun Chang, Yun-Chi Tang, Manajit Hayer-Hartl, and F. Ulrich Hartl Department of Cellular Biochemistry, Max Planck Institute of Biochemistry, Martinsried, Germany

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