Regulation of Muscle Glycogenolysis
During muscle contraction, a significant part of the energy used is derived from glycogen. The rate of glucose 1-phosphate production from glycogen is determined by the fraction of glycogen phosphorylase in the phosphorylated, active, a form (Madsen, 1986). The fractions of phosphorylase in the a and b (dephospho-, inactive) forms depend on the two enzymes, phosphorylase kinase and protein phosphatase-1, which in turn are influenced by other enzymes and regulatory factors, all of which form an integrated, multienzyme glycogenolytic complex (Fig. 1) (Hallenbeck & Walsh, 1986). In this report we describe three experimental approaches to the study of regulation of this complex.
KeywordsScanning Tunnelling Microscopy Glycogen Phosphorylase Glycogen Particle Phosphorylase Kinase Linear Aggregate
Unable to display preview. Download preview PDF.
- Chignell, D. A., Gratzer, W. B. & Valentine, R. C. (1968) J. Biol. Chem. 7, 1082–1089Google Scholar
- Dombradi, V., Gergely, P. & Bot, G. (1984) Acta Biochim. Biophys. Acad. Sci. Hung. 19, 193–201Google Scholar
- Madsen, N. B. (1986) in The Enzymes Vol. 17 (Boyer, P. D. & Krebs, E. G., eds.), pp. 365–394, Academic Press, OrlandoGoogle Scholar
- Pickett-Gies, C. A. & Walsh, D. A. (1986) in The Enzymes, Vol. 17 (Boyer, P. D. & Krebs, E. G., eds.), pp. 395–459, Academic Press, OrlandoGoogle Scholar
- Shatter, E., Chock, P. B. & Stadtman, E. R. (1984) J. Biol. Chem. 259, 12252–12259Google Scholar