Inability of insulin and insulinlike growth factor-1 to stimulate sugar or amino acid transport and thymidine incorporation in cultured myeloma cells.
NS-1 mouse plasmacytoma cells were examined for their insulin and insulinlike growth factor-1 (IGF-1) binding characteristics and ability to produce peptide-dependent cellular effects. At concentrations of labelled insulin (i.e., 1.7 x 10(-10) M) or IGF-1 (i.e., 1.5 x 10(-10) M), NS-1 cells specifically bind 0.2 +/- 0.06 fmol insulin per 10(6) cells (n = 7), where little, if any, IGF-1 specific binding was observed (0.02 +/- 0.01 fmol/10(6) cells) (n = 3). Additionally, the data indicate that the total number of insulin binding sites per cell was 3200 +/- 390 (n = 3). Insulin was employed at various concentrations (6.7-667 nM) and failed to stimulate either sugar or amino acid transport. Insulin at low concentrations (i.e., 6.7 or 67 nM) did not stimulate DNA synthesis, yet a small but significant increase was observed at a concentration of 667 nM insulin. IGF-1 did not stimulate DNA synthesis at all concentrations employed (1.4-143 nM). In summary, there exists a small but significant number of insulin receptors, little insulin-stimulated DNA synthesis, and no apparent insulin stimulation of sugar or amino acid transport. Also, since there is no significant IGF-1 binding and no IGF-1 stimulation of DNA synthesis, these findings indicate that this cell line might be a good candidate for the study of insulin receptor function as a transfection recipient of insulin receptor genes.
Leckett
B
B
Lady Davis Institute for Medical Research, Sir Mortimer B. Davis-Jewish General Hospital, Montreal (Quebec), Canada.
Germinario
R J
RJ
D000596:Amino Acids / Q000378:metabolism*; D000621:Aminoisobutyric Acids / Q000378:metabolism; D000818:Animals; D001665:Binding Sites; D001692:Biological Transport / Q000187:drug effects; D050260:Carbohydrate Metabolism; D004247:DNA / Q000096:biosynthesis*; D003847:Deoxyglucose / Q000378:metabolism; D007328:Insulin / Q000378:metabolism / Q000494:pharmacology*; D007334:Insulin-Like Growth Factor I / Q000378:metabolism / Q000494:pharmacology*; D051379:Mice; D010954:Plasmacytoma / Q000378:metabolism*; D011972:Receptor, Insulin / Q000378:metabolism; D011956:Receptors, Cell Surface / Q000378:metabolism; D017451:Receptors, Somatomedin; D013936:Thymidine / Q000378:metabolism; D014407:Tumor Cells, Cultured
D000596:Amino Acids; D000621:Aminoisobutyric Acids; D007328:Insulin; D011956:Receptors, Cell Surface; D017451:Receptors, Somatomedin; C100049:2-aminoisobutyric acid; D007334:Insulin-Like Growth Factor I; D004247:DNA; D003847:Deoxyglucose; D011972:Receptor, Insulin; D013936:Thymidine