{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,7]],"date-time":"2026-08-07T17:17:04Z","timestamp":1786123024343,"version":"build-2736575974"},"reference-count":47,"publisher":"American Chemical Society (ACS)","issue":"8","license":[{"start":{"date-parts":[[2026,7,29]],"date-time":"2026-07-29T00:00:00Z","timestamp":1785283200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/na","name":"Grantov? Agentura Cesk? 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Members of the Hsp70 family are known to form dimers and higher oligomers, but the structural organization and functional relevance of these assemblies remain poorly understood. Earlier studies also suggested that J-domain proteins (JDPs) can promote Hsp70 dimerization. In this study, we used chemical cross-linking, high-resolution Fourier transform mass spectrometry (FTMS), 15N isotopic labeling, and advanced data analysis to investigate the structural organization of Hsc70 dimers. Cross-link-derived distance restraints enabled structural modeling of Hsc70 monomers and dimers using AlphaLink2. Our results reveal distinct ATP- and ADP-state dimer conformations that coexist in equilibrium. In the presence of the cochaperone DnaJB1, we observed a shift in the dimer\u2013monomer equilibrium, accompanied by enhanced ATP hydrolysis and formation of intermediate species. These findings demonstrate that the Hsc70 dimer population is structurally heterogeneous and depends on nucleotide state and cochaperone interactions.<\/jats:p>","DOI":"10.1021\/acs.jproteome.6c00037","type":"journal-article","created":{"date-parts":[[2026,8,4]],"date-time":"2026-08-04T13:16:23Z","timestamp":1785849383000},"page":"4005-4017","source":"Crossref","is-referenced-by-count":0,"title":["Novel Insights\ninto the Human Hsc70 Structure by Cross-Linking\nMass Spectrometry and Molecular Modeling"],"prefix":"10.1021","volume":"25","author":[{"given":"Aleksandr","family":"Melikov","sequence":"first","affiliation":[{"name":"Institute of Microbiology, the Czech Academy of Sciences , ,","place":["Prague, Czech Republic, 14220"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Vsevolod","family":"Viliuga","sequence":"additional","affiliation":[{"name":"Stockholm University , , ,","place":["Stockholm, Sweden, 10405"]},{"name":"Science for Life Laboratory (SciLifeLab) , ,","place":["Stockholm, Sweden, 17165"]},{"name":"Max Planck Institute for Polymer Research , ,","place":["Mainz, Germany, 55128"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Daniel","family":"Kavan","sequence":"additional","affiliation":[{"name":"Institute of Microbiology, the Czech Academy of Sciences , ,","place":["Prague, Czech Republic, 14220"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7569-843X","authenticated-orcid":true,"given":"Zdene\u030ck","family":"Kukac\u030cka","sequence":"additional","affiliation":[{"name":"Institute of Microbiology, the Czech Academy of Sciences , ,","place":["Prague, Czech Republic, 14220"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7859-3112","authenticated-orcid":true,"given":"Matthias P.","family":"Mayer","sequence":"additional","affiliation":[{"name":"Center for Molecular Biology of Heidelberg University (ZMBH) , DKFZ-ZMBH-Alliance , ,","place":["Heidelberg, Germany, 69120"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8688-529X","authenticated-orcid":true,"given":"Petr","family":"Nova\u0301k","sequence":"additional","affiliation":[{"name":"Institute of Microbiology, the Czech Academy of Sciences , ,","place":["Prague, Czech Republic, 14220"]},{"name":"Charles University , , ,","place":["Prague, Czech Republic, 12820"]}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"316","published-online":{"date-parts":[[2026,7,29]]},"reference":[{"key":"2026080709085423000_cit1","doi-asserted-by":"publisher","first-page":"665","DOI":"10.1038\/s41580-019-0133-3","article-title":"The Hsp70 chaperone\nnetwork","volume":"20","author":"Rosenzweig","year":"2019","journal-title":"Nat. Rev. Mol. Cell Biol."},{"key":"2026080709085423000_cit2","doi-asserted-by":"publisher","first-page":"379","DOI":"10.1007\/s12192-016-0676-6","article-title":"The human\nHSP70 family of chaperones: where do we stand?","volume":"21","author":"Radons","year":"2016","journal-title":"Cell Stress and Chaperones"},{"key":"2026080709085423000_cit3","doi-asserted-by":"publisher","first-page":"38705","DOI":"10.1074\/jbc.M609020200","article-title":"Allosteric\nRegulation of Hsp70 Chaperones\nInvolves a Conserved Interdomain Linker","volume":"281","author":"Vogel","year":"2006","journal-title":"J.\nBiol. Chem."},{"key":"2026080709085423000_cit4","doi-asserted-by":"publisher","first-page":"670","DOI":"10.1007\/s00018-004-4464-6","article-title":"Hsp70 chaperones: Cellular\nfunctions and molecular mechanism","volume":"62","author":"Mayer","year":"2005","journal-title":"CMLS, Cell.\nMol. Life Sci."},{"key":"2026080709085423000_cit5","doi-asserted-by":"publisher","first-page":"aac4354","DOI":"10.1126\/science.aac4354","article-title":"In vivo aspects of protein folding\nand quality control","volume":"353","author":"Balchin","year":"2016","journal-title":"Science"},{"key":"2026080709085423000_cit6","doi-asserted-by":"publisher","first-page":"214","DOI":"10.1016\/j.molcel.2018.01.004","article-title":"Cellular Handling of Protein Aggregates\nby Disaggregation Machines","volume":"69","author":"Mogk","year":"2018","journal-title":"Mol. 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Proteome\nRes."},{"key":"2026080709085423000_cit25","doi-asserted-by":"publisher","DOI":"10.15252\/embj.2019104096","article-title":"Feedback regulation of heat shock\nfactor 1 (Hsf1) activity by Hsp70-mediated trimer unzipping and dissociation\nfrom DNA","volume":"39","author":"Kmiecik","year":"2020","journal-title":"EMBO Journal"},{"key":"2026080709085423000_cit26","volume-title":"Molecular Cloning:\nA Laboratory Manual","author":"Sambrook","year":"1989"},{"key":"2026080709085423000_cit27","doi-asserted-by":"publisher","first-page":"7866","DOI":"10.1038\/s41467-024-51771-2","article-title":"Modelling protein complexes with crosslinking mass\nspectrometry and deep learning","volume":"15","author":"Stahl","year":"2024","journal-title":"Nat. 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U.S.A."},{"key":"2026080709085423000_cit36","doi-asserted-by":"publisher","first-page":"48","DOI":"10.1016\/j.jprot.2014.02.004","article-title":"Structural\nand functional characterization of the chaperone Hsp70 from sugarcane.\nInsights into conformational changes during cycling from cross-linking\/mass\nspectrometry assays","volume":"104","author":"Tiroli-Cepeda","year":"2014","journal-title":"J. Proteomics"},{"key":"2026080709085423000_cit37","doi-asserted-by":"publisher","first-page":"8744","DOI":"10.1074\/jbc.272.13.8744","article-title":"The COOH-terminal\nPeptide Binding\nDomain Is Essential for Self-association of the Molecular Chaperone\nHSC70","volume":"272","author":"Benaroudj","year":"1997","journal-title":"J. Biol. Chem."},{"key":"2026080709085423000_cit38","doi-asserted-by":"publisher","first-page":"379","DOI":"10.1046\/j.1432-1327.1999.00053.x","article-title":"Oligomerization\nof the 17-kDa peptide-binding domain of the molecular chaperone HSC70","volume":"259","author":"Fouchaq","year":"1999","journal-title":"Eur. J. Biochem."},{"key":"2026080709085423000_cit39","doi-asserted-by":"publisher","first-page":"8849","DOI":"10.1074\/jbc.M114.596288","article-title":"A Functional DnaK Dimer\nIs Essential for the Efficient Interaction\nwith Hsp40 Heat Shock Protein","volume":"290","author":"Sarbeng","year":"2015","journal-title":"J. Biol. Chem."},{"key":"2026080709085423000_cit40","doi-asserted-by":"publisher","first-page":"320","DOI":"10.1074\/mcp.RA118.001044","article-title":"Human Stress-inducible Hsp70 Has a High Propensity\nto Form ATP-dependent\nAntiparallel Dimers That Are Differentially Regulated by Cochaperone\nBinding","volume":"18","author":"Trcka","year":"2019","journal-title":"Mol. 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Biosci."},{"key":"2026080709085423000_cit45","doi-asserted-by":"publisher","DOI":"10.1371\/journal.pbio.3001839","article-title":"Comprehensive\ncharacterization\nof the Hsp70 interactome reveals novel client proteins and interactions\nmediated by posttranslational modifications","volume":"20","author":"Nitika","year":"2022","journal-title":"PLoS Biol."},{"key":"2026080709085423000_cit46","doi-asserted-by":"publisher","first-page":"227","DOI":"10.1016\/j.molcel.2017.12.003","article-title":"Molecular\nMechanism of J-Domain-Triggered\nATP Hydrolysis by Hsp70 Chaperones","volume":"69","author":"Kityk","year":"2018","journal-title":"Mol. 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