title: Transport and phosphorylation of hexoses in normal and Rous sarcoma virus-transformed chick embryo fibroblasts.
abstract: Effects of transformation by Rous sarcoma virus on sugar uptake and activity and the subcellular distribution of hexokinase isozymes in chick embryo fibroblasts were examined. Transformation caused a several-fold increase in the maximum velocity for uptake of 2-deoxyglucose without a significant change in Km. Cytochalasin B (CB), was used to differentiate between the effects of transformation on facilitated diffusion and the nonsaturable (CB-insensitive) mode. Transformation was found to stimulate 2-deoxyglucose transport by both mechanisms, but the increase in transport by the CB-insensitive mode was greater. Transformation enhances the activity of hexokinase, the enhancement being confined to the particulate fraction of the enzyme. Heat-inactivation and electrophoretic mobility studies showed that although hexokinase Type I is the major form in both normal and transformed fibroblasts, there is a significant increase in the proportion of the Type II isozyme in the transformed cells.
mesh_terms: D000818:Animals; D001358:Avian Sarcoma Viruses; D001692:Biological Transport; D002472:Cell Transformation, Viral; D002478:Cells, Cultured; D002642:Chick Embryo; D003571:Cytochalasin B / Q000378:metabolism; D003847:Deoxyglucose / Q000378:metabolism; D005347:Fibroblasts / Q000201:enzymology / Q000378:metabolism; D006593:Hexokinase / Q000378:metabolism*; D006601:Hexoses / Q000378:metabolism*; D007527:Isoenzymes / Q000378:metabolism*; D010766:Phosphorylation
chemical_list: D006601:Hexoses; D007527:Isoenzymes; D003571:Cytochalasin B; D003847:Deoxyglucose; D006593:Hexokinase