Na(+)-dependent, active nucleoside transport in S49 mouse lymphoma cells and loss in AE-1 mutant deficient in facilitated nucleoside transport.
S49 murine lymphoma cells were examined for expression of various nucleoside transport systems using a non-metabolized nucleoside, formycin B, as substrate. Nitrobenzylthioinosine (NBTI)-sensitive, facilitated transport was the primary nucleoside transport system of the cells. The cells also expressed very low levels of NBTI-resistant, facilitated nucleoside transport as well as of Na(+)-dependent, concentrative formycin B transport. Concentrative transport was specific for uridine and purine nucleosides, just as the concentrative nucleoside transporters of other mouse and rat cells. A nucleoside transport mutant of S49 cells, AE-1, lacked both the NBTI-sensitive, facilitated and Na(+)-dependent, concentrative formycin B transport activity, but Na(+)-dependent, concentrative transport of alpha-aminoisobutyrate was not affected.
Plagemann
P G
PG
Department of Microbiology, Medical School, University of Minnesota, Minneapolis 55455.
D000621:Aminoisobutyric Acids / Q000378:metabolism; D000818:Animals; D001693:Biological Transport, Active; D002352:Carrier Proteins / Q000378:metabolism; D004176:Dipyridamole / Q000494:pharmacology; D005573:Formycins / Q000378:metabolism; D007700:Kinetics; D008223:Lymphoma; D008565:Membrane Proteins / Q000378:metabolism; D051379:Mice; D009154:Mutation; D033703:Nucleoside Transport Proteins; D009705:Nucleosides / Q000378:metabolism*; D012964:Sodium / Q000378:metabolism*; D013868:Thioinosine / Q000031:analogs & derivatives / Q000494:pharmacology; D014407:Tumor Cells, Cultured
D000621:Aminoisobutyric Acids; D002352:Carrier Proteins; D005573:Formycins; D008565:Membrane Proteins; D033703:Nucleoside Transport Proteins; D009705:Nucleosides; C034561:formycin B; C100049:2-aminoisobutyric acid; D013868:Thioinosine; D004176:Dipyridamole; D012964:Sodium; C001789:4-nitrobenzylthioinosine