Muscle glycogen synthase

Glycogen synthesis 1 Muscle glycogen synthase l Activity Muscle... 

Additional information <1> (<1> isozyme of calmodulin-dependent multifunctional protein kinase II in smooth-muscle [5] <1> caldesmon is not a substrate of smooth-muscle myosin light-chain kinase [3] <1> no substrates are bovine cardiac C-protein, bovine brain fodrin, rabbit skeletal muscle glycogen synthase, phosphorylase B, troponon (I -I- T -I- C), actin, tropomyosin, smooth-muscle actin, filamin, vinculin, cr-actinin, protamine or phosvitin [1]) [1-3]... 

Shulinan, R.G., Block, G., Rothman, D.L. (1995) In vivo regulation of muscle glycogen synthase and the control of glycogen synthesis. Proc. Natl. Acad. Sci. USA 92, 8535-8542. 

Breum L, Bjerre U, Bak JF, Jacobsen S, Astrup A (1995) Long-term effects of fluoxetine on glycemic control in obese patients with non-insulin-dependent diabetes mellitus or glucose intolerance influence on muscle glycogen synthase and insulin receptor kinase activity. Metabolism 44 1570-1576... 

As mentioned above, cAMP-dependent protein kinase phosphorylates and inactivates liver and muscle glycogen synthase [85,86]. Phosphorylation occurs at several serine residues in the muscle enzyme designated la, lb, 2, 3 and 4 [87-90] and it is probable that the phosphorylation pattern is similar in the liver enzyme [91,92]. Phosphorylation of site 1 of the muscle enzyme occurs more rapidly than the other sites [87], and sites 3 and 4 have only recently been recognized as phosphorylation sites [89]. All the sites are surrounded by amino acid sequences characteristic for cAMP-dependent protein kinase [90,93,94]. 

Pitcher, J., Smythe, C., Campbell, D. G., and Cohen, P. 1987. Identification of the 38-kDa subunit of rabbit skeletal muscle glycogen synthase as gtycogenin. Eur. J. Biochem. 169,497-502. 

R.G. Shulman and D.L. Rothman. 1996. Enzymatic phosphorylation of muscle glycogen synthase A mechanism for maintenance of metabolic homeostasis Proc. Natl. Acad. Sci. USA 93 7491-7495. (PubMed) (Full Text in PMC)... 

Table 14 In vivo phosphorylation sites in rabbit muscle glycogen synthase...

As seen in T able 14, there are two phosphorylation sites at the N-terminal region of the rabbit skeletal muscle glycogen synthase. The remaining seven are situated at the C-terminal region. The cAMP-dependent protein kinase preferentially phosphorylates three sites, la, lb, and 2. The cAMP-dependent kinase can also phosphoryiate sites 3a and 4 but at a much slower rate and thus is not considered to be as important as glycogen synthase kinase 3 for those sites. There are overlapping specificities among the different protein kinases for site 2 as phosphorylase kinase, calmodulin-dependent protein kinase and protein kinase C also can phosphoryiate this site. ... 

With respect to the liver glycogen synthase, the hormones glucagon, vasopressin, and epinephrine all increased the phosphorylation of the peptide regions containing the sites 2 and 3 and Akatsuka et showed that glucagon promoted phosphorylation of the casein kinase I site now referred to as site 2a or the equivalent liver Ser residue to muscle glycogen synthase residue, SerlO. 

Hannigan, L. L., Donahue, M. J. and Masaracchia, R. A. (1985) Comparative purification and characterization of invertebrate muscle glycogen synthase from the porcine parasite Ascaris suum. J. Biol. Chem. 260 16099-16105. 

ATP + rabbit muscle glycogen synthase <4> (<4> rabbit muscle glycogen synthase [10]) (Reversibility <4> [10]) [10]... 

Shulman, R. G., and D. L. Rothman. Enzymatic Phosphorylation of Muscle Glycogen Synthase A Mechanism for Maintenance of Metabolic Homeostasis. Proc. Nat. Acad. Sci. 93, 7491-7495 (1996). [An in-depth article about metabolic flux and covalent modification of enzymes.]... 

Glycogen storage disease type OB Muscle glycogen synthase GYSl ... 

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