Effect of insulin on the synthesis of rat liver ribosomal and endoplasmic reticulum proteins.
There was reduction in the levels of some liver endoplasmic reticulum proteins from streptozotocin-treated rats compared to those of normal rats as detected by two-dimensional polyacrylamide gel electrophoresis. When insulin was administered 24 h before streptozotocin, the protein patterns were the same as that obtained for normal rats. The comparison of the rate of synthesis of some endoplasmic proteins by streptozotocin-treated rats with that of streptozotocin-treated rats which received insulin 4 h prior to the experiment by the double-labelling technique indicated that insulin increased the rate of synthesis of some liver endoplasmic reticulum proteins. The rates of synthesis of some liver ribosomal proteins from streptozotocin-treated rats were increased and others were decreased when the animals were compared with streptozotocin-treated rats pretreated with insulin 4 h earlier. These results suggest that the generalized decrease of the rate of protein synthesis which has been reported in diabetes is due to a decrease of the rate of synthesis of some ribosomal proteins that may act in chain initiation or have a regulatory function.
D000818:Animals; D003921:Diabetes Mellitus, Experimental / Q000378:metabolism*; D004591:Electrophoresis, Polyacrylamide Gel; D004721:Endoplasmic Reticulum / Q000378:metabolism*; D005260:Female; D007328:Insulin / Q000494:pharmacology*; D008099:Liver / Q000378:metabolism*; D051381:Rats; D012269:Ribosomal Proteins / Q000096:biosynthesis*; D013311:Streptozocin
D007328:Insulin; D012269:Ribosomal Proteins; D013311:Streptozocin