Glucose stimulation of protein acylation in the pancreatic β-cell.
OBJECTIVE
To determine whether protein acylation plays a role in the effects of glucose on the insulin secreting β-cell.


METHODS
The measurement of (3)H-palmitate incorporation into protein in the INS 832/13 cell that has a robust and well-characterized biphasic insulin secretory response to stimulation with glucose.


RESULTS
Stimulating the cells with glucose increased the incorporation of (3)H-palmitic acid into protein by up to 90%. Similarly, 2-aminobicyclo [2.2.1] heptane-2-carboxylic acid (BCH) the non-metabolizable analog of leucine that mimics the stimulatory effect of glucose on insulin secretion also increased the incorporation of (3)H-palmitic acid into protein. Treatment of cell lysates with hydroxylamine substantially reduced the incorporation indicating that most of the incorporation was due to enzymatic palmitoylation of proteins. Cerulenin, a classical inhibitor of protein acylation also substantially reduced the incorporation. Using PAGE and autoradiography a glucose-induced increase in protein palmitoylation and specific glucose-induced increases in the palmitoylation of proteins of 30, 44, 48 and 76kD were identified.


CONCLUSIONS
The data suggest that protein acylation plays multiple roles in β-cell function.
Abdel-Ghany
Mossaad
M
The Department of Molecular Medicine, College of Veterinary Medicine, Cornell University, Ithaca, NY 14853, USA.
Sharp
Geoffrey W G
GW
Straub
Susanne G
SG
D000215:Acylation; D000598:Amino Acids, Cyclic / Q000494:pharmacology; D000818:Animals; D001345:Autoradiography; D002478:Cells, Cultured; D002569:Cerulenin / Q000494:pharmacology; D004591:Electrophoresis, Polyacrylamide Gel; D005947:Glucose / Q000008:administration & dosage / Q000378:metabolism*; D019811:Hydroxylamine / Q000494:pharmacology; D050417:Insulin-Secreting Cells / Q000378:metabolism*; D019308:Palmitic Acid / Q000378:metabolism*; D011506:Proteins / Q000378:metabolism*; D051381:Rats
D000598:Amino Acids, Cyclic; D011506:Proteins; D002569:Cerulenin; C006504:2-aminobicyclo(2,2,1)heptane-2-carboxylic acid; D019811:Hydroxylamine; D019308:Palmitic Acid; D005947:Glucose