2003 Fiscal Year Final Research Report Summary
Molecular mechanisms of insulin signal transduction and diabetes mellitus
Project/Area Number |
14370045
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Research Category |
Grant-in-Aid for Scientific Research (B)
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Allocation Type | Single-year Grants |
Section | 一般 |
Research Field |
General medical chemistry
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Research Institution | The University of Tokushima |
Principal Investigator |
EBINA Yousuke The University of Tokushima, Institute for Enzyme Research, Professor, 分子酵素学研究センター, 教授 (00112227)
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Co-Investigator(Kenkyū-buntansha) |
OBATA Toshiyuki The University of Tokushima, Institute for Enzyme Research, Research Associate, 分子酵素学研究センター, 助手 (40325296)
YUASA Tomoyuki The University of Tokushima, Institute for Enzyme Research, Research Associate, 分子酵素学研究センター, 助手 (50304556)
KISHI Kazuhiro The University of Tokushima, Institute for Enzyme Research, Associate Professor, 分子酵素学研究センター, 助教授 (70284320)
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Project Period (FY) |
2002 – 2003
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Keywords | Insulin signalling / APS / KO mouse / diabetes / Serum insulin receptor / 糖尿病 / 血中マーカー |
Research Abstract |
APS-deficient (APS(-/-)) mice were used to investigate its function in vivo. The blood glucose-lowering effect of insulin, as assessed by the intraperitoneal insulin tolerance test, was increased in APS(-/-) mice. APS(-/-) mice showed an increase in the whole-body glucose infusion rate as assessed by the hyperinsulinemic-euglycemic clamp test. These findings indicated that APS(-/-) mice exhibited increased sensitivity to insulin Using the expression vector of the truncated human insulin receptor (hIR), we have constructed a stable Chinese hamster ovary (CHO) cell line which secretes the His-tagged α subunit (insulin-binding domain) of hIR into medium. To examine characteristics of the His-tagged hIRα, we purified the protein secreted from the CHO cells. The His-tagged hIRα was glycosylated and processed a dimer. The molecule bound insulin with an affinity similar to that of the intact hIR. The His-tagged full length of hIR was autophosphorylated by insulin stimulation in CHO cells. Injection of the purified His-tagged hIRα into veins of mice increased in the concentration of blood glucose within 30 min. The intraperitoneal glucose tolerance test (ipGTT) done after injection of the purified His-tagged hIRα showed evidence of a marked hyperglycemia. These findings provide direct evidence that the presence of hlRα in the blood stream inhibits insulin actions by binding with plasma insulin
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Research Products
(10 results)