Insulin processing and action in adipocytes: evidence for generation of insulin-containing vesicles by leupeptin and monensin.
Incubation of adipocytes with 125I-insulin plus leupeptin or monensin, but not chloroquine, resulted in the appearance of a novel peak of 125I-insulin (modal density about 1.20 g/ml) on density gradient centrifugation; the appearance of the peak depended on the presence of specific insulin receptors on the cell surface. The fractions comprising this peak contained vesicles, probably originating from the Golgi apparatus, and dit not appear to be contaminated with lysosomes, mitochondria or plasma membrane. Entrapment of insulin in these vesicles per se did not prevent the activation of glucose transport, acetyl-CoA carboxylase or pyruvate dehydrogenase by insulin.
Jeffrey
I W
IW
Flint
D J
DJ
Vernon
R G
RG
Mayer
R J
RJ
D000103:Acetyl-CoA Carboxylase / Q000378:metabolism; D000273:Adipose Tissue / Q000187:drug effects / Q000378:metabolism* / Q000648:ultrastructure; D000818:Animals; D002499:Centrifugation, Density Gradient; D003847:Deoxyglucose / Q000378:metabolism; D004789:Enzyme Activation / Q000187:drug effects; D005260:Female; D005663:Furans / Q000494:pharmacology*; D007328:Insulin / Q000378:metabolism* / Q000494:pharmacology; D007976:Leupeptins / Q000494:pharmacology*; D008854:Microscopy, Electron; D008985:Monensin / Q000494:pharmacology*; D009842:Oligopeptides / Q000494:pharmacology*; D009940:Organoids / Q000378:metabolism; D011768:Pyruvate Dehydrogenase Complex / Q000378:metabolism; D051381:Rats; D011919:Rats, Inbred Strains
D005663:Furans; D007328:Insulin; D007976:Leupeptins; D009842:Oligopeptides; D011768:Pyruvate Dehydrogenase Complex; D008985:Monensin; D003847:Deoxyglucose; D000103:Acetyl-CoA Carboxylase; C032854:leupeptin