Glycogen biogenesis in the adipocyte and mammary adenocarcinoma and the influence of insulin.
3T3 LI P-3 adipocytes and a rat mammary carcinoma each contain a protein (or proteins) of Mr 400 kDa approx. that undergoes glucosylation when incubated with UDPglucose and Mn2+. In each case, the product of glucosylation is a protein-bound maltosaccharide containing up to 14 glucose residues, and therefore capable of priming glycogen synthesis. The proteins bear a formal similarity to the self-glucosylating protein of Mr 37 kDa that primes muscle glycogen synthesis, but do not cross-react with an antibody that cross-reacts with the muscle protein. The extent of protein glucosylation in the adipocyte is rapidly and markedly stimulated when the cells are bathed in insulin, suggesting that this initial step in glycogen biogenesis, protein glucosylation, is under the influence of the hormone.
Lomako
J
J
Department of Biochemistry and Molecular Biology, University of Miami, Florida 33101.
Lomako
W M
WM
Whelan
W J
WJ
D000230:Adenocarcinoma / Q000378:metabolism*; D000273:Adipose Tissue / Q000166:cytology / Q000378:metabolism*; D000818:Animals; D003429:Cross Reactions; D004591:Electrophoresis, Polyacrylamide Gel; D005947:Glucose / Q000378:metabolism; D006003:Glycogen / Q000096:biosynthesis*; D007328:Insulin / Q000494:pharmacology*; D008325:Mammary Neoplasms, Experimental / Q000378:metabolism*; D009363:Neoplasm Proteins / Q000378:metabolism; D011506:Proteins / Q000378:metabolism; D051381:Rats; D014407:Tumor Cells, Cultured
D007328:Insulin; D009363:Neoplasm Proteins; D011506:Proteins; D006003:Glycogen; D005947:Glucose