TY - JOUR
T1 - The overexpression of insulin receptor makes CHO cells resistant to the action of IGF-1
T2 - Role of IRS-1
AU - Maggi, D.
AU - Laurino, C.
AU - Andraghetti, G.
AU - Cordera, R.
PY - 1994
Y1 - 1994
N2 - We investigated the influence of the relative abundance of insulin and IGF-1 receptors on cellular growth, by measuring the stimulation of c-fos expression and of 3H-thymidine incorporation into DNA by insulin and IGF-1 in CHO cells overexpressing Insulin Receptor (CHO-IR). We found that CHO-IR cells were resistant to the action of IGF-1, but were more responsive to insulin, compared to parental clone. This result suggested the presence of a limiting step, distal to the IGF-1 receptor, in the transduction pathway. To address this question we measured the IGF-1 effect on c-fos expression in CHO-IR cells, transiently transfected with the cDNA for IRS-1, the common intracellular substrate for both insulin and IGF-1 receptors (CHO-IR/IRS-1 cells). In these cells IGF-1 stimulated a 10 fold higher c-fos expression compared to CHO-IR cells. These results suggest that the abundance of IRS-1, relative to the number of insulin and IGF-1 receptors, represents a limiting step for the intracellular transduction of insulin and IGF-1 biological messages.
AB - We investigated the influence of the relative abundance of insulin and IGF-1 receptors on cellular growth, by measuring the stimulation of c-fos expression and of 3H-thymidine incorporation into DNA by insulin and IGF-1 in CHO cells overexpressing Insulin Receptor (CHO-IR). We found that CHO-IR cells were resistant to the action of IGF-1, but were more responsive to insulin, compared to parental clone. This result suggested the presence of a limiting step, distal to the IGF-1 receptor, in the transduction pathway. To address this question we measured the IGF-1 effect on c-fos expression in CHO-IR cells, transiently transfected with the cDNA for IRS-1, the common intracellular substrate for both insulin and IGF-1 receptors (CHO-IR/IRS-1 cells). In these cells IGF-1 stimulated a 10 fold higher c-fos expression compared to CHO-IR cells. These results suggest that the abundance of IRS-1, relative to the number of insulin and IGF-1 receptors, represents a limiting step for the intracellular transduction of insulin and IGF-1 biological messages.
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U2 - 10.1006/bbrc.1994.2721
DO - 10.1006/bbrc.1994.2721
M3 - Article
C2 - 7999100
AN - SCOPUS:0028033666
VL - 205
SP - 693
EP - 699
JO - Biochemical and Biophysical Research Communications
JF - Biochemical and Biophysical Research Communications
SN - 0006-291X
IS - 1
ER -