title: A major collagen-binding protein of chick embryo fibroblasts is a novel heat shock protein.
abstract: Heat shock proteins of chick embryo fibroblasts were analyzed on SDS polyacrylamide gradient gels and were found to include not only three previously well-characterized proteins of 25,000, 73,000, and 89,000 D, but also a 47,000-D protein. Two-dimensional gel electrophoresis revealed that this protein was unusually basic (pI = 9.0) and corresponded to a recently characterized, major gelatin- and collagen-binding protein. The induction of synthesis of this 47,000-D membrane glycoprotein after heat stress of fibroblasts was particularly apparent in preparations isolated by gelatin-affinity chromatography. Regulation of this 47,000-D phosphoprotein was more sensitive than that of three major heat shock proteins in that a substantial stimulation of synthesis occurred at even 42 degrees C, as well as at higher temperature. Phosphorylation of the 47,000-D protein was not altered after heat shock. These studies establish this phosphorylated membrane glycoprotein as a member of the heat shock/stress protein family, and they add collagen binding to the unexpectedly diverse spectrum of biochemical activities induced by exposure of cells to stress.
mesh_terms: D000818:Animals; D001151:Arsenic / Q000494:pharmacology; D018053:Arsenites; D002352:Carrier Proteins / Q000378:metabolism*; D002462:Cell Membrane / Q000378:metabolism; D002478:Cells, Cultured; D002642:Chick Embryo; D003094:Collagen / Q000378:metabolism*; D005786:Gene Expression Regulation; D006023:Glycoproteins / Q000378:metabolism; D006360:Heat-Shock Proteins / Q000378:metabolism*; D066298:In Vitro Techniques; D008565:Membrane Proteins / Q000378:metabolism; D008970:Molecular Weight; D010750:Phosphoproteins / Q000378:metabolism*; D013997:Time Factors
chemical_list: D018053:Arsenites; D002352:Carrier Proteins; D006023:Glycoproteins; D006360:Heat-Shock Proteins; D008565:Membrane Proteins; D010750:Phosphoproteins; D003094:Collagen; C015001:arsenite; D001151:Arsenic