Tunicamycin tightens the glucose- and D-allose-mediated control of hexose transport in a metabolic fibroblast mutant.
AUTOR(ES)
Ullrey, D B
RESUMO
The hexose transport system of a fibroblast mutant, DS7, unable to convert glucose 6-phosphate to fructose 6-phosphate ("the phosphoglucose isomerase mutant"), is subject to a specific down-regulation ("curb") evoked by only glucose or D-allose. Neither fructose nor mannose has a curbing effect on this mutant. Further addition of tunicamycin intensified the transport curb on the mutant mediated by glucose or allose. Mannose added to the parental cell line 023 seems able to mimic a glucose-mediated transport curb. In this line, but not the mutant, tunicamycin also intensifies a mannose-mediated curb. It seems that the tightening of the allose-mediated curb is a function of a specific type of transport regulation and perhaps too of interference with glycosylation of the hexose transporter. Furthermore, this type of curb can be strikingly reversed by shifting the cultures to medium containing fructose.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=304938Documentos Relacionados
- Hexose transport control in a fibroblast metabolic mutant can be promoted more effectively by D-allose than by glucose.
- Further clues concerning the vectors essential to regulation of hexose transport, as studied in fibroblast cultures from a metabolic mutant.
- Concerted hexose transport curb by tunicamycin is rendered irreversible by glucose or allose in medium containing L-glutamine.
- Down-regulation of the hexose transport system: metabolic basis studied with a fibroblast mutant lacking phosphoglucose isomerase.
- Effects of combined glutamine and serum deprivation on glucose control of hexose transport in mammalian fibroblast cultures.