Biochemical characterization of the 94- and 78-kilodalton glucose-regulated proteins in hamster fibroblasts.
This report concerns further characterization of the 94-kDa and the 78-kDA glucose-regulated proteins which are the major proteins overproduced in hamster fibroblasts when the cells are starved of glucose. Using a temperature-sensitive mutant, K12, which synthesizes high levels of these proteins at the nonpermissive temperature, we purified both proteins by two-dimensional gel electrophoresis and determined their amino acid compositions as well as the NH2-terminal sequences. Both proteins contain an unusual NH2-terminal sequence rich in glutamic and aspartic acid residues. Biochemical fractionation of these proteins demonstrated that the 78-kDa glucose-regulated protein is present in the nuclear fraction. In addition, we show that phosphate incorporation into the 78-kDa protein is specifically affected in the K12 mutant cells.
D000595:Amino Acid Sequence; D000818:Animals; D002460:Cell Line; D006224:Cricetinae; D004591:Electrophoresis, Polyacrylamide Gel; D005947:Glucose / Q000378:metabolism*; D018840:HSP70 Heat-Shock Proteins; D008565:Membrane Proteins / Q000096:biosynthesis* / Q000302:isolation & purification; D010766:Phosphorylation
D018840:HSP70 Heat-Shock Proteins; D008565:Membrane Proteins; C018551:glucose-regulated proteins; D005947:Glucose