Skip to main content
Biochemical Journal logoLink to Biochemical Journal
. 2000 Nov 1;351(Pt 3):811–816.

Shared control of hepatic glycogen synthesis by glycogen synthase and glucokinase.

R R Gomis 1, J C Ferrer 1, J J Guinovart 1
PMCID: PMC1221423  PMID: 11042138

Abstract

We have used recombinant adenoviruses (AdCMV-RLGS and AdCMV-GK) to overexpress the liver isoforms of glycogen synthase (GS) and glucokinase (GK) in primary cultured rat hepatocytes. Glucose activated overexpressed GS in a dose-dependent manner and caused the accumulation of larger amounts of glycogen in the AdCMV-RLGS-treated hepatocytes. The concentration of intermediate metabolites of the glycogenic pathway, such as glucose 6-phosphate (Glc-6-P) and UDP-glucose, were not significantly altered. GK overexpression also conferred on the hepatocyte an enhanced capacity to synthesize glycogen in response to glucose, as described previously [Seoane, Gómez-Foix, O'Doherty, Gómez-Ara, Newgard and Guinovart (1996) J. Biol. Chem. 271, 23756-23760], although, in this case, they accumulated Glc-6-P. When GS and GK were simultaneously overexpressed, the accumulation of glycogen was enhanced in comparison with cells overexpressing either GS or GK. Our results are consistent with the hypothesis that liver GS catalyses the rate-limiting step of hepatic glycogen synthesis. However, hepatic glycogen deposition from glucose is submitted to a system of shared control in which the 'controller', GS, is, in turn, controlled by GK. This control is indirectly exerted through Glc-6-P, which 'switches on' GS dephosphorylation and activation.

Full Text

The Full Text of this article is available as a PDF (177.2 KB).

Selected References

These references are in PubMed. This may not be the complete list of references from this article.

  1. Agius L., Peak M. Intracellular binding of glucokinase in hepatocytes and translocation by glucose, fructose and insulin. Biochem J. 1993 Dec 15;296(Pt 3):785–796. doi: 10.1042/bj2960785. [DOI] [PMC free article] [PubMed] [Google Scholar]
  2. Aiston S., Trinh K. Y., Lange A. J., Newgard C. B., Agius L. Glucose-6-phosphatase overexpression lowers glucose 6-phosphate and inhibits glycogen synthesis and glycolysis in hepatocytes without affecting glucokinase translocation. Evidence against feedback inhibition of glucokinase. J Biol Chem. 1999 Aug 27;274(35):24559–24566. doi: 10.1074/jbc.274.35.24559. [DOI] [PubMed] [Google Scholar]
  3. Antinozzi P. A., Berman H. K., O'Doherty R. M., Newgard C. B. Metabolic engineering with recombinant adenoviruses. Annu Rev Nutr. 1999;19:511–544. doi: 10.1146/annurev.nutr.19.1.511. [DOI] [PubMed] [Google Scholar]
  4. Azpiazu I., Manchester J., Skurat A. V., Roach P. J., Lawrence J. C., Jr Control of glycogen synthesis is shared between glucose transport and glycogen synthase in skeletal muscle fibers. Am J Physiol Endocrinol Metab. 2000 Feb;278(2):E234–E243. doi: 10.1152/ajpendo.2000.278.2.E234. [DOI] [PubMed] [Google Scholar]
  5. Bai G., Zhang Z. J., Werner R., Nuttall F. Q., Tan A. W., Lee E. Y. The primary structure of rat liver glycogen synthase deduced by cDNA cloning. Absence of phosphorylation sites 1a and 1b. J Biol Chem. 1990 May 15;265(14):7843–7848. [PubMed] [Google Scholar]
  6. Baqué S., Guinovart J. J., Gómez-Foix A. M. Overexpression of muscle glycogen phosphorylase in cultured human muscle fibers causes increased glucose consumption and nonoxidative disposal. J Biol Chem. 1996 Feb 2;271(5):2594–2598. doi: 10.1074/jbc.271.5.2594. [DOI] [PubMed] [Google Scholar]
  7. Becker T. C., Noel R. J., Coats W. S., Gómez-Foix A. M., Alam T., Gerard R. D., Newgard C. B. Use of recombinant adenovirus for metabolic engineering of mammalian cells. Methods Cell Biol. 1994;43(Pt A):161–189. doi: 10.1016/s0091-679x(08)60603-2. [DOI] [PubMed] [Google Scholar]
  8. Berman H. K., O'Doherty R. M., Anderson P., Newgard C. B. Overexpression of protein targeting to glycogen (PTG) in rat hepatocytes causes profound activation of glycogen synthesis independent of normal hormone- and substrate-mediated regulatory mechanisms. J Biol Chem. 1998 Oct 9;273(41):26421–26425. doi: 10.1074/jbc.273.41.26421. [DOI] [PubMed] [Google Scholar]
  9. Bradford M. M. A rapid and sensitive method for the quantitation of microgram quantities of protein utilizing the principle of protein-dye binding. Anal Biochem. 1976 May 7;72:248–254. doi: 10.1016/0003-2697(76)90527-3. [DOI] [PubMed] [Google Scholar]
  10. Chan T. M., Exton J. H. A rapid method for the determination of glycogen content and radioactivity in small quantities of tissue or isolated hepatocytes. Anal Biochem. 1976 Mar;71(1):96–105. doi: 10.1016/0003-2697(76)90014-2. [DOI] [PubMed] [Google Scholar]
  11. Fernández-Novell J. M., Bellido D., Vilaró S., Guinovart J. J. Glucose induces the translocation of glycogen synthase to the cell cortex in rat hepatocytes. Biochem J. 1997 Jan 1;321(Pt 1):227–231. doi: 10.1042/bj3210227. [DOI] [PMC free article] [PubMed] [Google Scholar]
  12. Ferrannini E., Bjorkman O., Reichard G. A., Jr, Pilo A., Olsson M., Wahren J., DeFronzo R. A. The disposal of an oral glucose load in healthy subjects. A quantitative study. Diabetes. 1985 Jun;34(6):580–588. doi: 10.2337/diab.34.6.580. [DOI] [PubMed] [Google Scholar]
  13. Ferrer J. C., Baqué S., Guinovart J. J. Muscle glycogen synthase translocates from the cell nucleus to the cystosol in response to glucose. FEBS Lett. 1997 Oct 6;415(3):249–252. doi: 10.1016/s0014-5793(97)01136-8. [DOI] [PubMed] [Google Scholar]
  14. Gustafson L. A., Jumelle-Laclau M. N., van Woerkom G. M., van Kuilenburg A. B., Meijer A. J. Cell swelling and glycogen metabolism in hepatocytes from fasted rats. Biochim Biophys Acta. 1997 Jan 16;1318(1-2):184–190. doi: 10.1016/s0005-2728(96)00128-4. [DOI] [PubMed] [Google Scholar]
  15. Kuwajima M., Newgard C. B., Foster D. W., McGarry J. D. The glucose-phosphorylating capacity of liver as measured by three independent assays. Implications for the mechanism of hepatic glycogen synthesis. J Biol Chem. 1986 Jul 5;261(19):8849–8853. [PubMed] [Google Scholar]
  16. Lavoinne A., Baquet A., Hue L. Stimulation of glycogen synthesis and lipogenesis by glutamine in isolated rat hepatocytes. Biochem J. 1987 Dec 1;248(2):429–437. doi: 10.1042/bj2480429. [DOI] [PMC free article] [PubMed] [Google Scholar]
  17. Manchester J., Skurat A. V., Roach P., Hauschka S. D., Lawrence J. C., Jr Increased glycogen accumulation in transgenic mice overexpressing glycogen synthase in skeletal muscle. Proc Natl Acad Sci U S A. 1996 Oct 1;93(20):10707–10711. doi: 10.1073/pnas.93.20.10707. [DOI] [PMC free article] [PubMed] [Google Scholar]
  18. Massagué J., Guinovart J. J. Insulin control of rat hepatocyte glycogen synthase and phosphorylase in the absence of glucose. FEBS Lett. 1977 Oct 15;82(2):317–320. doi: 10.1016/0014-5793(77)80610-8. [DOI] [PubMed] [Google Scholar]
  19. O'Doherty R. M., Lehman D. L., Seoane J., Gómez-Foix A. M., Guinovart J. J., Newgard C. B. Differential metabolic effects of adenovirus-mediated glucokinase and hexokinase I overexpression in rat primary hepatocytes. J Biol Chem. 1996 Aug 23;271(34):20524–20530. doi: 10.1074/jbc.271.34.20524. [DOI] [PubMed] [Google Scholar]
  20. Roach P. J., Cheng C., Huang D., Lin A., Mu J., Skurat A. V., Wilson W., Zhai L. Novel aspects of the regulation of glycogen storage. J Basic Clin Physiol Pharmacol. 1998;9(2-4):139–151. doi: 10.1515/jbcpp.1998.9.2-4.139. [DOI] [PubMed] [Google Scholar]
  21. Seoane J., Gómez-Foix A. M., O'Doherty R. M., Gómez-Ara C., Newgard C. B., Guinovart J. J. Glucose 6-phosphate produced by glucokinase, but not hexokinase I, promotes the activation of hepatic glycogen synthase. J Biol Chem. 1996 Sep 27;271(39):23756–23760. doi: 10.1074/jbc.271.39.23756. [DOI] [PubMed] [Google Scholar]
  22. Seoane J., Trinh K., O'Doherty R. M., Gómez-Foix A. M., Lange A. J., Newgard C. B., Guinovart J. J. Metabolic impact of adenovirus-mediated overexpression of the glucose-6-phosphatase catalytic subunit in hepatocytes. J Biol Chem. 1997 Oct 24;272(43):26972–26977. doi: 10.1074/jbc.272.43.26972. [DOI] [PubMed] [Google Scholar]
  23. Thomas J. A., Schlender K. K., Larner J. A rapid filter paper assay for UDPglucose-glycogen glucosyltransferase, including an improved biosynthesis of UDP-14C-glucose. Anal Biochem. 1968 Oct 24;25(1):486–499. doi: 10.1016/0003-2697(68)90127-9. [DOI] [PubMed] [Google Scholar]
  24. Thorens B., Cheng Z. Q., Brown D., Lodish H. F. Liver glucose transporter: a basolateral protein in hepatocytes and intestine and kidney cells. Am J Physiol. 1990 Dec;259(6 Pt 1):C279–C285. doi: 10.1152/ajpcell.1990.259.2.C279. [DOI] [PubMed] [Google Scholar]
  25. Towbin H., Staehelin T., Gordon J. Electrophoretic transfer of proteins from polyacrylamide gels to nitrocellulose sheets: procedure and some applications. 1979. Biotechnology. 1992;24:145–149. [PubMed] [Google Scholar]
  26. Villar-Palasí C., Guinovart J. J. The role of glucose 6-phosphate in the control of glycogen synthase. FASEB J. 1997 Jun;11(7):544–558. [PubMed] [Google Scholar]

Articles from Biochemical Journal are provided here courtesy of The Biochemical Society

RESOURCES