Abstract
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.
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Selected References
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- Haspel H. C., Wilk E. W., Birnbaum M. J., Cushman S. W., Rosen O. M. Glucose deprivation and hexose transporter polypeptides of murine fibroblasts. J Biol Chem. 1986 May 25;261(15):6778–6789. [PubMed] [Google Scholar]
- Kalckar H. M., Ullrey D. B. Further clues concerning the vectors essential to regulation of hexose transport, as studied in fibroblast cultures from a metabolic mutant. Proc Natl Acad Sci U S A. 1984 Feb;81(4):1126–1129. doi: 10.1073/pnas.81.4.1126. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Olden K., Pratt R. M., Jaworski C., Yamada K. M. Evidence for role of glycoprotein carbohydrates in membrane transport: specific inhibition by tunicamycin. Proc Natl Acad Sci U S A. 1979 Feb;76(2):791–795. doi: 10.1073/pnas.76.2.791. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Pouysségur J., Franchi A., Salomon J. C., Silvestre P. Isolation of a Chinese hamster fibroblast mutant defective in hexose transport and aerobic glycolysis: its use to dissect the malignant phenotype. Proc Natl Acad Sci U S A. 1980 May;77(5):2698–2701. doi: 10.1073/pnas.77.5.2698. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Tkacz J. S., Lampen O. Tunicamycin inhibition of polyisoprenyl N-acetylglucosaminyl pyrophosphate formation in calf-liver microsomes. Biochem Biophys Res Commun. 1975 Jul 8;65(1):248–257. doi: 10.1016/s0006-291x(75)80086-6. [DOI] [PubMed] [Google Scholar]
- Ullrey D. B., Kalckar H. M. Hexose transport control in a fibroblast metabolic mutant can be promoted more effectively by D-allose than by glucose. Proc Natl Acad Sci U S A. 1986 Aug;83(16):5858–5860. doi: 10.1073/pnas.83.16.5858. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Ullrey D. B., Kalckar H. M. Schism and complementation of hexose-mediated transport regulation as illustrated in a fibroblast mutant lacking phosphoglucose-isomerase. Biochem Biophys Res Commun. 1982 Aug 31;107(4):1532–1538. doi: 10.1016/s0006-291x(82)80173-3. [DOI] [PubMed] [Google Scholar]
