Characteristics of protein tyrosine kinase activities of Y-79 retinoblastoma cells and retina.
Protein tyrosine kinase activities were determined in retina and Y-79 retinoblastoma cells. Kinase activity was associated with particulate subcellular fractions. Specific activities were similar in both retina and Y-79 cells; apparent Km values for ATP and casein were also similar. Retinoblastoma-derived growth factor stimulated endogenous protein tyrosine phosphorylation in Y-79 cells significantly more than in retina. Differences in protein tyrosine phosphorylation between retina and Y-79 retinoblastoma appear to be due to differences in regulation of the activity by the growth factor or differences in the endogenous protein substrates present in the Y-79 cells.
D000818:Animals; D002460:Cell Line; D002852:Chromatography, Ion Exchange; D006801:Humans; D008253:Macaca mulatta; D010766:Phosphorylation; D011494:Protein Kinases / Q000378:metabolism*; D011505:Protein-Tyrosine Kinases; D012160:Retina / Q000201:enzymology*; D012175:Retinoblastoma / Q000201:enzymology*; D012995:Solubility; D013347:Subcellular Fractions / Q000201:enzymology; D013379:Substrate Specificity
D011494:Protein Kinases; D011505:Protein-Tyrosine Kinases