Post-translational control by carrier availability of amino acid transport in fetal human fibroblasts.
The action of serum on the expression of the starvation-enhanced amino acid transport by System A (as a part of the adaptive regulation mechanism) has been studied in cultured fetal human fibroblasts. Serum enhanced L-proline uptake of cells starved in serum-free medium. This effect was rapid, proportional to the amount of pre-existing transporters, insensitive to cycloheximide and kinetically characterized by an increase of transport Vmax. These results can be interpreted to indicate that serum is essential for a vectorial post-translational event leading to insertion of transport proteins into the cell membrane.
D000596:Amino Acids / Q000378:metabolism*; D001692:Biological Transport / Q000187:drug effects; D001790:Blood Physiological Phenomena; D002478:Cells, Cultured; D003470:Culture Media; D003513:Cycloheximide / Q000494:pharmacology; D005333:Fetus; D005347:Fibroblasts / Q000378:metabolism*; D006801:Humans; D008297:Male; D011392:Proline / Q000378:metabolism; D011499:Protein Processing, Post-Translational
D000596:Amino Acids; D003470:Culture Media; D003513:Cycloheximide; D011392:Proline