Search Organism: All OrganismsArabidopsis thalianaBacillus subtilis 168Bos taurusCaenorhabditis elegansCanis familiarisDanio rerioDrosophila melanogasterEquus caballusEscherichia coli K12Gallus gallusHomo sapiensMacaca mulattaMus musculusNematostella vectensisOryza sativaPan troglodytesRattus norvegicusSaccharomyces cerevisiaeSchizosaccharomyces pombeStrongylocentrotus purpuratusTakifugu rubripesXenopus laevis home help / support contribute downloads mirrors about us J. Mol. Biol. Oct (2008); 383(1):155-66 Conserved central domains control the quaternary structure of type I and type II Hsp40 molecular chaperones- Ramos CH, Oliveira CL, Fan CY, Torriani IL, Cyr DM Department of Organic Chemistry, Institute of Chemistry, University of Campinas-UNICAMP, Campinas, SP 13083-970, Brazil- cramos@iqm-unicamp-br Abstract: Heat shock protein -Hsp-40s play an essential role in protein metabolism by regulating the polypeptide binding and release cycle of Hsp70- The Hsp40 family is large, and specialized family members direct Hsp70 to perform highly specific tasks- Type I and Type II Hsp40s, such as yeast Ydj1 and Sis1, are homodimers that dictate functions of cytosolic Hsp70, but how they do so is unclear- Type I Hsp40s contain a conserved, centrally located cysteine-rich domain that is replaced by a glycine- and methionine-rich region in Type II Hsp40s, but the mechanism by which these unique domains influence Hsp40 structure and function is unknown- This is the case because high-resolution structures of full-length forms of these Hsp40s have not been solved- To fill this void, we built low-resolution models of the quaternary structure of Ydj1 and Sis1 with information obtained from biophysical measurements of protein shape, small-angle X-ray scattering, and ab initio protein modeling- Low-resolution models were also calculated for the chimeric Hsp40s YSY and SYS, in which the central domains of Ydj1 and Sis1 were exchanged- Similar to their human homologs, Ydj1 and Sis1 each has a unique shape with major structural differences apparently being the orientation of the J domains relative to the long axis of the dimers- Central domain swapping in YSY and SYS correlates with the switched ability of YSY and SYS to perform unique functions of Sis1 and Ydj1, respectively- Models for the mechanism by which the conserved cysteine-rich domain and glycine- and methionine-rich region confer structural and functional specificity to Type I and Type II Hsp40s are discussed- [PUBMED: 18723025] Copyright © 2009, Tyers Lab, The Samuel Lunenfeld Research Institute, Mount Sinai Hospital, All Rights Reserved. terms and conditions - privacy policy - Osprey Network Visualization System BioGRID: A General Repository for Interaction Datasets. Chris Stark, Bobby-Joe Breitkreutz, Teresa Reguly, Lorrie Boucher, Ashton Breitkreutz, Mike Tyers. Nucleic Acids Res. Jan 1;34:D535-9.