Abstract
Diabetes affects 3% of the European population and 140 million people Worldwide, and is largely a disease of insulin resistance in which the tissues fail to respond to this hormone. This emphasizes the importance of understanding how insulin signals to the cell's interior. We have recently dissected a protein kinase cascade that is triggered by the formation of the insulin 'second messenger' Phosphatidylinositide (3,4,5) trisphosphate (PtdIns(3,4,5)P3) and which appears to mediate many of the metabolic actions of this hormone. The first enzyme in the cascade is termed 3-phosphoinositide-dependent protein kinase-1 (PDK1), because it only activates protein kinase B (PKB), the next enzyme in the pathway, in the presence of PtdIns(3,4,5)P3. PKB then inactivates glycogen synthase kinase-3 (GSK3). PDK1, PKB and GSK3 regulate many physiological events by phosphorylating a variety of intracellular proteins. In addition, PKB plays an important role in mediating protection against apoptosis by survival factors, such as insulin-like growth factor-1.
Original language | English |
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Pages (from-to) | 485-495 |
Number of pages | 11 |
Journal | Philosophical Transactions of the Royal Society B: Biological Sciences |
Volume | 354 |
Issue number | 1382 |
DOIs | |
Publication status | Published - 28 Feb 1999 |
Keywords
- Apoptosis
- Diabetes
- IGF1
- Inositol phospholipid
- Insulin
- Protein kinase
ASJC Scopus subject areas
- General Biochemistry,Genetics and Molecular Biology
- General Agricultural and Biological Sciences