Expression of a dominant-negative mutant human insulin receptor in the muscle of transgenic mice.
To examine the in vivo effects of a kinase-deficient mutant human insulin receptor, we used the muscle creatine kinase promoter to express a putative dominant-negative receptor: Ala1134-->Thr (Moller, D. E., Yokota, A., White, M. F., Pazianos, A. G., and Flier, J. S. (1990) J. Biol. Chem. 265, 14979-14985) in transgenic mice. Two lines were generated, where receptor expression was restricted to striated muscle and was increased by 5-12-fold in skeletal muscle. Transgenic gluteal muscle insulin receptor kinase activity was reduced by approximately 80% after maximal in vitro insulin stimulation. Glycogen content in this muscle was reduced by 45% in transgenic mice. Insulin levels were approximately 2-fold higher, and glucose concentrations were 12% higher in transgenics fed ad libitum. Transgenic mice exhibited reduced in vivo sensitivity to low dose (0.1 milliunits/g) intravenous insulin. In isolated soleus muscles from transgenics, where mutant receptors were expressed at lower levels, insulin-stimulated receptor kinase activity was reduced by 42%, but insulin-stimulated 2-deoxyglucose uptake was unaffected. These results indicate that (i) overexpression of a kinase-deficient human insulin receptor in muscle causes dominant-negative effects at the level of receptor kinase activation, (ii) impairment of insulin-stimulated muscle receptor tyrosine kinase activity can cause decreased insulin sensitivity in vivo, (iii) kinase-defective receptor mutants may be used to create novel animal models of tissue-specific insulin resistance.
Chang
P Y
PY
Charles A. Dana Research Institute, Boston, Massachusetts.
Benecke
H
H
Le Marchand-Brustel
Y
Y
Lawitts
J
J
Moller
D E
DE
D000818:Animals; D001483:Base Sequence; D002081:Buttocks; D003847:Deoxyglucose / Q000378:metabolism; D005947:Glucose / Q000378:metabolism; D005951:Glucose Tolerance Test; D006003:Glycogen / Q000032:analysis; D006801:Humans; D007328:Insulin / Q000494:pharmacology; D051379:Mice; D008822:Mice, Transgenic; D008969:Molecular Sequence Data; D009132:Muscles / Q000502:physiology*; D009154:Mutation; D011505:Protein-Tyrosine Kinases / Q000502:physiology*; D011972:Receptor, Insulin / Q000502:physiology*; D014018:Tissue Distribution
D007328:Insulin; D006003:Glycogen; D003847:Deoxyglucose; D011505:Protein-Tyrosine Kinases; D011972:Receptor, Insulin; D005947:Glucose