Translational control of an intestinal microvillar enzyme.
The rates of biosynthesis of adult and foetal pig small-intestinal aminopeptidase N (EC 3.4.11.2) were compared to determine at which level the expression of the microvillar enzyme is developmentally controlled. In organ-cultured explants, the rate of biosynthesis of foetal aminopeptidase N is only about 3% of the adult rate. The small amount synthesized occurs in a high-mannose-glycosylated, membrane-bound, form that is processed to the mature, complex-glycosylated, form at a markedly slower rate than that of the adult enzyme. Extracts of total RNA from adult and foetal intestine contained comparable amounts of aminopeptidase N mRNA, encoding gel-electrophoretically identical primary translation products. Together, these data indicate that the expression of aminopeptidase N is controlled at a translational level.
D000626:Aminopeptidases / Q000096:biosynthesis / Q000235:genetics*; D000818:Animals; D018826:CD13 Antigens; D002474:Cell-Free System; D004591:Electrophoresis, Polyacrylamide Gel; D005786:Gene Expression Regulation; D007413:Intestinal Mucosa / Q000196:embryology / Q000201:enzymology*; D008871:Microvilli / Q000201:enzymology; D009924:Organ Culture Techniques; D014176:Protein Biosynthesis; D012333:RNA, Messenger / Q000235:genetics; D013552:Swine
D012333:RNA, Messenger; D000626:Aminopeptidases; D018826:CD13 Antigens