Baculoviral expression of a natural inhibitor of the human insulin receptor tyrosine kinase.
We had earlier reported that the human serum alpha 2-HS glycoprotein (1) is a physiological and specific inhibitor of the human insulin receptor tyrosine kinase (IR-TK). We have now expressed this human protein in the baculoviral expression system using the Sf-9 and High Five insect cells. The protein was optimally expressed at 72 h post infection. alpha 2-HSGbac completely inhibited the insulin-stimulated autophosphorylation and TK activity of partially purified IR preparations. It also abolished insulin-induced DNA synthesis in the H-35 rat hepatoma cell line. The effective concentration of the baculoviral derived alpha 2-HSG necessary for inhibiting IR-TK activity was significantly lower than that of the protein purified from human plasma.
Srinivas
P R
PR
Center for Molecular Medicine and Genetics, Wayne State University, Detroit, MI 48201.
Goustin
A S
AS
Grunberger
G
G
D000818:Animals; D001483:Base Sequence; D001798:Blood Proteins / Q000235:genetics / Q000494:pharmacology*; D002455:Cell Division / Q000187:drug effects; D003001:Cloning, Molecular; D017931:DNA Primers / Q000737:chemistry; D006801:Humans; D066298:In Vitro Techniques; D007328:Insulin / Q000494:pharmacology; D008969:Molecular Sequence Data; D017924:Nucleopolyhedroviruses; D010766:Phosphorylation; D011505:Protein-Tyrosine Kinases / Q000037:antagonists & inhibitors; D011972:Receptor, Insulin / Q000037:antagonists & inhibitors*; D011994:Recombinant Proteins / Q000494:pharmacology; D018411:Spodoptera; D013997:Time Factors; D060749:alpha-2-HS-Glycoprotein
C556354:AHSG protein, human; D001798:Blood Proteins; D017931:DNA Primers; D007328:Insulin; D011994:Recombinant Proteins; D060749:alpha-2-HS-Glycoprotein; D011505:Protein-Tyrosine Kinases; D011972:Receptor, Insulin