Various pathological conditions in man, such as type II Diabetes Mellitus, are characterized by a failure of the cell to respond to insulin. Insulin is a major anabolic hormone, which stimulates the cellular uptake of nutrients and diverse other substances necessary for cellular function. This stimulatory effect is mediated in part through a rapid increase in the cell surface number of specialized transport proteins and of high affinity receptors for extracellular macromolecules such as transferrin, alpha 2 macroglobulin and insulin-like growth factor II. The long term goal of this project is to elucidate the molecular mechanisms that are involved in the stimulation by insulin of the cell surface expression of receptors for extracellular macromolecules. Previous data have shown that the process of endocytosis of high affinity receptors for extracellular macromolecules is regulated by insulin. Preliminary data presented in this proposal, have provided evidence to indicate that the clathrin coated structures in the plasma membrane which mediate the endocytosis of these receptors may be an important target for insulin action. In this work, cellular fractionation techniques, methods for in-vitro reconstitution of clathrin coated pit formation, and monoclonal antibodies to coated membrane components will be used to a) further analyze which of the steps involved in the assembly and disassembly of clathrin coated pits is sensitive to insulin action, b) to test the hypothesis that casein kinase 2 is one of the key elements involved in this process, and c) to test the hypothesis that the effects of insulin on clathrin coated structures and on receptor endocytosis are mediated through casein kinase 2.

Agency
National Institute of Health (NIH)
Institute
National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK)
Type
Research Project (R01)
Project #
5R01DK040330-04
Application #
3240523
Study Section
Cellular Biology and Physiology Subcommittee 1 (CBY)
Project Start
1988-09-01
Project End
1992-04-30
Budget Start
1990-09-01
Budget End
1992-04-30
Support Year
4
Fiscal Year
1990
Total Cost
Indirect Cost
Name
University of Massachusetts Medical School Worcester
Department
Type
Schools of Medicine
DUNS #
660735098
City
Worcester
State
MA
Country
United States
Zip Code
01655
Klarlund, J K; Rameh, L E; Cantley, L C et al. (1998) Regulation of GRP1-catalyzed ADP ribosylation factor guanine nucleotide exchange by phosphatidylinositol 3,4,5-trisphosphate. J Biol Chem 273:1859-62
Shpetner, H; Joly, M; Hartley, D et al. (1996) Potential sites of PI-3 kinase function in the endocytic pathway revealed by the PI-3 kinase inhibitor, wortmannin. J Cell Biol 132:595-605
Hartley, D; Corvera, S (1996) Formation of c-Cbl.phosphatidylinositol 3-kinase complexes on lymphocyte membranes by a p56lck-independent mechanism. J Biol Chem 271:21939-43
Joly, M; Kazlauskas, A; Corvera, S (1995) Phosphatidylinositol 3-kinase activity is required at a postendocytic step in platelet-derived growth factor receptor trafficking. J Biol Chem 270:13225-30
Hartley, D; Meisner, H; Corvera, S (1995) Specific association of the beta isoform of the p85 subunit of phosphatidylinositol-3 kinase with the proto-oncogene c-cbl. J Biol Chem 270:18260-3
Joly, M; Kazlauskas, A; Fay, F S et al. (1994) Disruption of PDGF receptor trafficking by mutation of its PI-3 kinase binding sites. Science 263:684-7
Chakrabarti, R; Joly, M; Corvera, S (1993) Redistribution of clathrin-coated vesicle adaptor complexes during adipocytic differentiation of 3T3-L1 cells. J Cell Biol 123:79-87
Kapeller, R; Chakrabarti, R; Cantley, L et al. (1993) Internalization of activated platelet-derived growth factor receptor-phosphatidylinositol-3' kinase complexes: potential interactions with the microtubule cytoskeleton. Mol Cell Biol 13:6052-63
Corvera, S; Jaspers, S; Pasceri, M (1991) Acute inhibition of insulin-stimulated glucose transport by the phosphatase inhibitor, okadaic acid. J Biol Chem 266:9271-5
Corvera, S; Capocasale, R J (1990) Enhanced phosphorylation of a coated vesicle polypeptide in response to insulin stimulation of rat adipocytes. J Biol Chem 265:15963-9

Showing the most recent 10 out of 12 publications