Differential regulation of the GLUT-1 and GLUT-4 glucose transport systems by glucose and insulin in L6 muscle cells in culture
| Autor: | U M Koivisto, Toolsie Ramlal, Amira Klip, E Burdett, H Martinez-Valdez, Philip J. Bilan |
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| Rok vydání: | 1991 |
| Předmět: |
Starvation
endocrine system medicine.medical_specialty Insulin medicine.medical_treatment Glucose transporter Cell Biology Membrane transport Biology Biochemistry carbohydrates (lipids) Endocrinology Downregulation and upregulation Internal medicine medicine Myocyte medicine.symptom Molecular Biology hormones hormone substitutes and hormone antagonists Hexose transport Pancreatic hormone |
| Zdroj: | Journal of Biological Chemistry. 266:2615-2621 |
| ISSN: | 0021-9258 |
| DOI: | 10.1016/s0021-9258(18)52289-4 |
| Popis: | The regulation by glucose and insulin of the muscle-specific facilitative glucose transport system GLUT-4 was investigated in L6 muscle cells in culture. Hexose transport activity, mRNA expression, and the subcellular localization of the GLUT-4 protein were analyzed. As observed previously (Walker, P. S., Ramlal, T., Sarabia, V., Koivisto, U.-M., Bilan, P. J., Pessin, J. E., and Klip, A. (1990) J. Biol. Chem. 265, 1516-1523), 24 h of glucose starvation and 24 h of insulin treatment each increase glucose transport activity severalfold. Here we report a differential regulation of the GLUT-4 and GLUT-1 transport systems under these conditions. (a) The level of GLUT-4 mRNA was not affected by glucose starvation and was diminished by prolonged (24 h) administration of insulin; in contrast, the level of GLUT-1 mRNA was elevated under both conditions. (b) Glucose starvation and prolonged insulin administration increased the amount of both GLUT-4 and GLUT-1 proteins in the plasma membrane. (c) In intracellular membranes, glucose starvation elevated, and prolonged insulin administration reduced, the GLUT-4 protein content. In contrast, the GLUT-1 protein content in these membranes decreased with glucose starvation and increased with insulin treatment. Glucose transport was rapidly curbed upon refeeding glucose to glucose-starved cells, with half-maximal reversal after 30 min and maximal reversal after 4 h. This was followed by a marked decrease in the levels of GLUT-1 mRNA without major changes in GLUT-4 mRNA. Neither 2-deoxy-D-glucose nor 3-O-methyl-D-glucose could substitute for D-glucose in these effects. It is proposed that glucose and insulin differentially regulate the two glucose transport systems in L6 muscle cells and that the rapid down-regulation of hexose transport activity by glucose is regulated by post-translational mechanisms. |
| Databáze: | OpenAIRE |
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