Amino acid deprivation leads to the emergence of System A activity and the synthesis of a specific membrane glycoprotein in the bovine renal epithelial cell line NBL-1.
1. Amino acid deprivation of confluent monolayers of the bovine renal epithelial cell line NBL-1 causes a stimulation of Na(+)-dependent alanine transport. 2. This stimulation is mediated by a protein-synthesis-dependent induction of 2-(methylamino)isobutyric acid (methyl-AIB)-sensitive alanine transport activity (System A), which was not previously present in these cells. 3. Induction was prevented by the addition of methyl-AIB, alanine or glutamine. 4. Tunicamycin prevented the induction of alanine transport activity. 5. Induction of System A activity was accompanied by incorporation of [3H]mannose into a single membrane protein band of molecular mass 113-140 kDa. 6. These results are consistent with the possibility that induced System A activity in confluent NBL-1 cells is mediated by the synthesis of a 113-140 kDa membrane glycoprotein.
Felipe
A
A
Department of Biochemistry, University of Bristol, School of Medical Sciences, U.K.
Soler
C
C
McGivan
J D
JD
D000409:Alanine / Q000378:metabolism; D000596:Amino Acids / Q000378:metabolism*; D000621:Aminoisobutyric Acids / Q000378:metabolism; D000818:Animals; D001692:Biological Transport / Q000187:drug effects; D002417:Cattle; D002460:Cell Line; D004591:Electrophoresis, Polyacrylamide Gel; D004847:Epithelial Cells; D004848:Epithelium / Q000378:metabolism; D007668:Kidney / Q000166:cytology / Q000378:metabolism*; D008358:Mannose / Q000378:metabolism; D008562:Membrane Glycoproteins / Q000378:metabolism*; D012964:Sodium / Q000378:metabolism; D014415:Tunicamycin / Q000494:pharmacology
D000596:Amino Acids; D000621:Aminoisobutyric Acids; D008562:Membrane Glycoproteins; D014415:Tunicamycin; C017911:2-(methylamino)isobutyric acid; D012964:Sodium; D000409:Alanine; D008358:Mannose