Molecular cloning of the human glucose-regulated protein ERp57/GRP58, a thiol-dependent reductase. Identification of its secretory form and inducible expression by the oncogenic transformation.
Recently it was shown that putative phospholipase C-alpha cDNA does not code for an isotype of the phospholipase C superfamily but for one of the glucose-regulated proteins (GRPs), ERp57/GRP58. We have isolated human ERp57/GRP58 cDNA from human placenta. Sequence analysis showed that ERp57/GRP58 has two Trp-Cys-Gly-His-Cys-Lys motifs completely conserved among the mammals. Bacterially expressed recombinant ERp57/GRP58 protein contained a thiol-dependent reductase activity which was completely abolished when Ser residues were substituted for Cys residues in both of the two motifs. Furthermore, we have identified a soluble form of ERp57/GRP58 by Western blotting and biosynthetic labeling. In v-onc transformants of normal rat kidney cells, the expression level of ERp57/GRP58 was elevated at the protein level. In NIH3T3 cells transformed with v-src, activated c-src (Y527F) or c-src, the expression level of ERp57/GRP58 was upregulated in proportion to their transforming abilities. These results indicate that a soluble form of ERp57/GRP58 exists and that this protein may control both extracellular and intracellular redox activities through its thiol-dependent reductase activity. Moreover, it is likely that ERp57/GRP58 is involved in the oncogenic transformation.
Third Department of Internal Medicine, Faculty of Medicine, University of Tokyo, Japan.
N
N
Hirano
F
F
Shibasaki
R
R
Sakai
T
T
Tanaka
J
J
Nishida
Y
Y
Yazaki
T
T
Takenawa
H
H
Hirai
D016475:3T3 Cells; D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D002384:Catalysis; D002461:Cell Line, Transformed; D002471:Cell Transformation, Neoplastic; D003001:Cloning, Molecular; D018076:DNA, Complementary; D004229:Dithiothreitol / Q000378:metabolism; D004926:Escherichia coli / Q000235:genetics; D015971:Gene Expression Regulation, Enzymologic; D015972:Gene Expression Regulation, Neoplastic; D006360:Heat-Shock Proteins / Q000235:genetics* / Q000378:metabolism; D006801:Humans; D007328:Insulin / Q000378:metabolism; D007535:Isomerases; D051379:Mice; D008969:Molecular Sequence Data; D009857:Oncogenes; D010084:Oxidation-Reduction; D010088:Oxidoreductases / Q000235:genetics* / Q000378:metabolism; D019704:Protein Disulfide-Isomerases; D017386:Sequence Homology, Amino Acid; D013438:Sulfhydryl Compounds / Q000378:metabolism*
D018076:DNA, Complementary; D006360:Heat-Shock Proteins; D007328:Insulin; D013438:Sulfhydryl Compounds; D010088:Oxidoreductases; D007535:Isomerases; C513196:PDIA3 protein, rat; C513195:Pdia3 protein, mouse; D019704:Protein Disulfide-Isomerases; C085868:PDIA3 protein, human; D004229:Dithiothreitol