Abstract
Pig small intestinal mRNA was translated in a rabbit reticulocyte lysate system supplemented with microsomal membranes. Castanospermine, an inhibitor of glucosidase I, induced a high mannose-glycosylated form of microvillar aminopeptidase N (EC 3.4.11.2) of increased molecular mass, indicating the blocked removal of glucose residues. In contrast to its reduced expression in a mucosal explant system [(1986) Biochem. J. 240, 777-782], this molecular form of aminopeptidase N was at least as abundant in cell-free translation as its normal high mannose-glycosylated counterpart, ruling out degradation taking place in the rough endoplasmic reticulum. Degradation of newly produced, malprocessed enzyme must therefore occur at a later stage during intracellular transport, presumably in the sarcoplasmic reticulum or in transitional elements between this organelle and the Golgi complex.
Original language | English |
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Journal | FEBS Letters |
Volume | 228 |
Issue number | 1 |
Pages (from-to) | 102-4 |
Number of pages | 2 |
ISSN | 0014-5793 |
Publication status | Published - 1988 |