Control of glucose phosphorylation and glucose usage in clonal insulinoma cells.
Glucose metabolism was investigated in two established clonal insulinoma cell lines (RINm5F and HIT) and in a newly developed line of mouse insulinoma cells (IgSV195). The hexokinase capacity in the homogenates of RINm5F cells was 22.1 +/- 3.23 U/g protein, but glucokinase was barely detectable (0.06 +/- 0.013 U/g protein). In contrast, both HIT and IgSV195 cells contained glucokinase (1.5 +/- 0.17 and 1.0 +/- 0.16 U/g protein, respectively) in addition to hexokinase activity. Glucose usage by the intact cells qualitatively reflected the glucose phosphorylation found in the cell-free extracts. RINm5F cells exhibited a high glucose usage rate with one high-affinity component, whereas both HIT and IgSV195 cells showed two components with different glucose affinities. HIT and IgSV195 cells may be useful for a model of pancreatic beta-cell glycolysis.
Shimizu
T
T
Department of Biochemistry and Biophysics, University of Pennsylvania, Philadelphia 19104.
Knowles
B B
BB
Matschinsky
F M
FM
D007516:Adenoma, Islet Cell / Q000378:metabolism*; D000818:Animals; D002460:Cell Line; D002999:Clone Cells; D005941:Glucokinase / Q000378:metabolism; D005947:Glucose / Q000378:metabolism* / Q000502:physiology; D006019:Glycolysis; D006593:Hexokinase / Q000378:metabolism; D007340:Insulinoma / Q000378:metabolism*; D007515:Islets of Langerhans / Q000378:metabolism; D051379:Mice; D010190:Pancreatic Neoplasms / Q000378:metabolism*; D010766:Phosphorylation
D006593:Hexokinase; D005941:Glucokinase; D005947:Glucose