This research proposal for the first three years of a SERCA in diabetes: obstetrical, perinatal and/or pediatric aspects, outlines a plan encompassing three major areas of investigation: (1) The structure, function and regulation of phosphoprotein phosphatases will be studied. Electroblotting after gel electrophoresis, coupled with peroxidase-linked immunoassay will allow detection of enzymes and their proteolytic fragments. By applying this to an insulin-sensitive adipocyte suspension, the nature of insulin regulation of phosphatases will be further elucidated. This project will require 80% effort during the first two years of the SERCA. (2) During the third year, investigation of changes in red cell glycolysis associated with non-enzymatic, post-translational glycosylation of enzymes is planned. Erythrocytes exposed to normal and elevated glucose concentration in vivo and in vitro will be studied for changes in glycolytic intermediates and enzyme activities. Red cells from diabetic and non-diabetic pregnant women, normal infants, infants of diabetic mothers, normal children and diabetic children will be used. Glycosylation of enzymes will be demonstrated through chromatofocusing and boronic acid-affinity chromatography. (3) Investigation into the effects of primary hyperinsulinemia in the Rhesus monkey fetus will proceed through the implantation of an osmotically driven, insulincontaining minipump in the fetus 21 days prior to delivery. Newborn counterregulatory response to hypoglycemia and the effects of in utero hyperinsulinemia on pancreatic function in the infant monkey will be studied. While working on these projects, clinical responsibility (1/2 day per week) for the Diabetes and Metabolism Clinic will continue. Coursework in hormonal regulation of metabolism and statistics is planned. During the fourth and fifth years of the award developmental aspects of phosphoprotein phosphatases and the effects of fetal hyper- and hypoinsulinemia will be pursued. Studies on glycosylation of glycolytic enzymes in the erythrocyte could be applied to the hepatocyte. This proposal is intended to provide training in biochemistry, biochemical pharmacology, enzymology and hormone physiology, thereby providing the groundwork for further research endeavors.
| Domenech, M; Gruppuso, P A; Nishino, V T et al. (1986) Preserved fetal plasma amino acid concentrations in the presence of maternal hypoaminoacidemia. Pediatr Res 20:1071-6 |
| Brautigan, D L; Gruppuso, P A; Mumby, M (1986) Protein phosphatase type-1 and type-2 catalytic subunits both bind inhibitor-2 and monoclonal immunoglobulins. J Biol Chem 261:14924-8 |
| Elbein, S C; Gruppuso, P; Schwartz, R et al. (1985) Hyperproinsulinemia in a family with a proposed defect in conversion is linked to the insulin gene. Diabetes 34:821-4 |
| Gruppuso, P A; Johnson, G L; Constantinides, M et al. (1985) Phosphorylase phosphatase regulatory subunit. ""Western"" blotting with immunoglobulins against inhibitor-2 reveals a protein of Mr = 60,000. J Biol Chem 260:4288-94 |
| Brautigan, D L; Shriner, C L; Gruppuso, P A (1985) Phosphorylase phosphatase catalytic subunit. Evidence that the Mr = 33,000 enzyme fragment is derived from a native protein of Mr = 70,000. J Biol Chem 260:4295-302 |
