title: Reconstitution of the multiprotein complex of pp60src, hsp90, and p50 in a cell-free system.
abstract: A rabbit reticulocyte lysate system that has been used to reconstitute functional complexes between steroid receptors and the 90-kDa heat shock protein (hsp90) has been used here to form complexes between the pp60src tyrosine kinase and hsp90. Reticulocyte lysate forms complexes between hsp90 and a temperature-sensitive mutant of Rous sarcoma virus pp60v-src, which is normally present in cytosol virtually entirely in the multiprotein complex form. In addition, hsp90 in the lysate complexes with wild-type pp60v-src, of which only a small portion is normally recovered in cytosol in the native multiprotein complex, and with the cellular homolog, pp60c-src, which has never been recovered in cytosol in the form of a native multiprotein complex with hsp90. Moreover, the reticulocyte lysate-reconstituted complex also contains the 50-kDa phosphoprotein component of the native pp60v-src multiprotein complex. The native and reconstituted pp60src-hsp90 complexes have similar thermal stability and, like steroid receptor heterocomplexes, they are stabilized by molybdate. As previously shown with reticulocyte lysate-reconstituted steroid receptor heteroprotein complexes, the reconstituted pp60src multiprotein complex contains hsp70, which is a major candidate for providing the protein unfoldase activity required for hsp90 association.
authors.affiliation: Department of Pharmacology, University of Michigan Medical School, Ann Arbor 48109.
authors.forename: K A
authors.initials: KA
authors.lastname: Hutchison
authors.forename: B K
authors.initials: BK
authors.lastname: Brott
authors.forename: J H
authors.initials: JH
authors.lastname: De Leon
authors.forename: G H
authors.initials: GH
authors.lastname: Perdew
authors.forename: R
authors.initials: R
authors.lastname: Jove
authors.forename: W B
authors.initials: WB
authors.lastname: Pratt
mesh_terms: D000818:Animals; D001358:Avian Sarcoma Viruses / Q000235:genetics; D003600:Cytosol / Q000378:metabolism; D004355:Drug Stability; D004591:Electrophoresis, Polyacrylamide Gel; D006360:Heat-Shock Proteins / Q000302:isolation & purification / Q000378:metabolism*; D015151:Immunoblotting; D046911:Macromolecular Substances; D008970:Molecular Weight; D008982:Molybdenum / Q000494:pharmacology; D046912:Multiprotein Complexes; D015688:Oncogene Protein pp60(v-src) / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*; D010750:Phosphoproteins / Q000302:isolation & purification / Q000378:metabolism*; D011817:Rabbits; D012156:Reticulocytes / Q000378:metabolism*
chemical_list: D006360:Heat-Shock Proteins; D046911:Macromolecular Substances; D046912:Multiprotein Complexes; D010750:Phosphoproteins; D008982:Molybdenum; C024687:sodium molybdate(VI); D015688:Oncogene Protein pp60(v-src)