The sulfhydryl groups of muscle phosphorylase. V. The reactive sulfhydryl peptides

1970 ◽  
Vol 48 (7) ◽  
pp. 763-775 ◽  
Author(s):  
C. G. Zarkadas ◽  
L. B. Smillie ◽  
N. B. Madsen
Keyword(s):  
Skeletal Muscle ◽  
Molecular Weight ◽  
Muscle Glycogen ◽  
Glycogen Phosphorylase ◽  
Chromatographic Purification ◽  
Model Compounds ◽  
Rate Of Reaction ◽  
Peptic Digestion ◽  
Muscle Phosphorylase ◽  
Column Chromatographic

Skeletal muscle glycogen phosphorylase a and b have previously been shown to consist of four and two subunits, respectively, each having a molecular weight of 92 500. Our studies have indicated that there is a minimum of eight and a maximum of nine unique cysteine sequences in the enzyme providing additional evidence that the subunits are identical. From the known sequences of the nine sulfhydryl peptides it was possible to isolate and characterize the reactive sulfhydryl peptides of phosphorylase. Careful column chromatographic purification of alkylated peptides derived from peptic digestion showed that there are two cysteine residues per monomer of phosphorylase b whose rate of reaction with iodoacetamide approaches that of model compounds and whose alkylation does not affect significantly the enzymic properties of the protein. These two cysteines have been identified in sequences corresponding to numbers 2 and 5 previously elucidated. These sequences have been extended in the present work and may now be written as: No. 2 Asn–Gln–Lys–Ile–CMC–Gly–Gly–Try–Gln–Ser, and No. 5 Gly–CMC–Arg–Asp–Pro–Val–Arg–Thr–Asn–Phe.

scholarly journals Adenovirus-mediated delivery into myocytes of muscle glycogen phosphorylase, the enzyme deficient in patients with glycogen-storage disease type V

1994 ◽  
Vol 304 (3) ◽  
pp. 1009-1014 ◽  
Author(s):  
S Baqué ◽  
C B Newgard ◽  
R D Gerard ◽  
J J Guinovart ◽  
A M Gómez-Foix
Keyword(s):  
Muscle Glycogen ◽  
Glycogen Phosphorylase ◽  
Recombinant Adenovirus ◽  
Genetic Diseases ◽  
C2c12 Myoblast ◽  
Mrna Levels ◽  
Phosphorylase Activity ◽  
Muscle Phosphorylase ◽  
The Impact

The feasibility of using adenovirus as a vector for the introduction of glycogen phosphorylase activity into myocytes has been examined. We used the C2C12 myoblast cell line to assay the impact of phosphorylase gene transfer on myocyte glycogen metabolism and to reproduce in vitro the two strategies proposed for the treatment of muscle genetic diseases, myoblast transplantation and direct DNA delivery. In this study, a recombinant adenovirus containing the muscle glycogen phosphorylase cDNA transcribed from the cytomegalovirus promoter (AdCMV-MGP) was used to transduce both differentiating myoblasts and nondividing mature myotube cells. Muscle glycogen phosphorylase mRNA levels and total phosphorylase activity were increased in both cell types after viral treatment although more efficiently in the differentiated myotubes. The increase in phosphorylase activity was transient (15 days) in myoblasts whereas in myotubes higher levels of phosphorylase gene expression and activity were reached, which remained above control levels for the duration of the study (20 days). The introduction of muscle phosphorylase into myotubes enhanced their glycogenolytic capacity. AdCMV MGP-transduced myotubes had lower glycogen levels under basal conditions. In addition, these engineered cells showed more extensive glycogenolysis in response to both adrenaline, which stimulates glycogen phosphorylase phosphorylation, and carbonyl cyanide m-chlorophenylhydrazone, a metabolic uncoupler. In conclusion, transfer of the muscle glycogen phosphorylase cDNA into myotubes confers an enhanced and regulatable glycogenolytic capacity. Thus this system might be useful for delivery of muscle glycogen phosphorylase and restoration of glycogenolysis in muscle cells from patients with muscle phosphorylase deficiency (McArdle's disease).

Lack of defect in insulin action on hepatic glycogen synthase and phosphorylase in insulin-resistant monkeys

1998 ◽  
Vol 274 (6) ◽  
pp. G1005-G1010
Author(s):  
Heidi K. Ortmeyer ◽  
Noni L. Bodkin
Keyword(s):  
Insulin Resistance ◽  
Skeletal Muscle ◽  
Muscle Glycogen ◽  
Rhesus Monkeys ◽  
Insulin Action ◽  
Glycogen Phosphorylase ◽  
Glycogen Synthase ◽  
Liver Glycogen ◽  
Hepatic Glycogen ◽  
Insulin Resistant

It is well known that an alteration in insulin activation of skeletal muscle glycogen synthase is associated with insulin resistance. To determine whether this defect in insulin action is specific to skeletal muscle, or also present in liver, simultaneous biopsies of these tissues were obtained before and during a euglycemic hyperinsulinemic clamp in spontaneously obese insulin-resistant male rhesus monkeys. The activities of glycogen synthase and glycogen phosphorylase and the concentrations of glucose 6-phosphate and glycogen were measured. There were no differences between basal and insulin-stimulated glycogen synthase and glycogen phosphorylase activities or in glucose 6-phosphate and glycogen contents in muscle. Insulin increased the activities of liver glycogen synthase ( P < 0.05) and decreased the activities of liver glycogen phosphorylase ( P ≤ 0.001). Insulin also caused a reduction in liver glucose 6-phosphate ( P = 0.05). We conclude that insulin-resistant monkeys do not have a defect in insulin action on liver glycogen synthase, although a defect in insulin action on muscle glycogen synthase is present. Therefore, tissue-specific alterations in insulin action on glycogen synthase are present in the development of insulin resistance in rhesus monkeys.

scholarly journals Systemic AAV8-mediated delivery of a functional copy of muscle glycogen phosphorylase (Pygm) ameliorates disease in a murine model of McArdle disease

2019 ◽  
Vol 29 (1) ◽  
pp. 20-30 ◽  
Author(s):  
Elyshia L McNamara ◽  
Rhonda L Taylor ◽  
Joshua S Clayton ◽  
Hayley Goullee ◽  
Kimberley L Dilworth ◽  
...  
Keyword(s):  
Skeletal Muscle ◽  
Animal Model ◽  
Murine Model ◽  
Muscle Glycogen ◽  
Glycogen Phosphorylase ◽  
Large Animal ◽  
Mcardle Disease ◽  
Increased Risk ◽  
Virus Serotype ◽  
Functional Copy

Abstract McArdle disease is a disorder of carbohydrate metabolism that causes painful skeletal muscle cramps and skeletal muscle damage leading to transient myoglobinuria and increased risk of kidney failure. McArdle disease is caused by recessive mutations in the muscle glycogen phosphorylase (PYGM) gene leading to absence of PYGM enzyme in skeletal muscle and preventing access to energy from muscle glycogen stores. There is currently no cure for McArdle disease. Using a preclinical animal model, we aimed to identify a clinically translatable and relevant therapy for McArdle disease. We evaluated the safety and efficacy of recombinant adeno-associated virus serotype 8 (rAAV8) to treat a murine model of McArdle disease via delivery of a functional copy of the disease-causing gene, Pygm. Intraperitoneal injection of rAAV8-Pygm at post-natal day 1–3 resulted in Pygm expression at 8 weeks of age, accompanied by improved skeletal muscle architecture, reduced accumulation of glycogen and restoration of voluntary running wheel activity to wild-type levels. We did not observe any adverse reaction to the treatment at 8 weeks post-injection. Thus, we have investigated a highly promising gene therapy for McArdle disease with a clear path to the ovine large animal model endemic to Western Australia and subsequently to patients.

Phosphorylase and glycogen levels in skeletal muscle and liver of hibernating and nonhibernating bats

1959 ◽  
Vol 197 (5) ◽  
pp. 1059-1062 ◽  
Author(s):  
Samuel L. Leonard ◽  
William A. Wimsatt
Keyword(s):  
Skeletal Muscle ◽  
Muscle Glycogen ◽  
Liver Glycogen ◽  
Myotis Lucifugus ◽  
Phosphorylase Activity ◽  
Activity Ratios ◽  
Muscle Phosphorylase ◽  
Wet Weight ◽  
Muscle Phosphorylase Activity ◽  
Made In

Determinations of skeletal muscle and liver glycogen concentration and active a and total t phosphorylase activities were made in bats ( Myotis lucifugus) hibernating at 3°–5° and 20 hours after arousal at room temperature. After arousal, liver glycogen was decreased by half and muscle glycogen was increased over twofold. Concomitantly, muscle phosphorylase a was increased, phosphorylase t was unchanged and the ratio a/t was increased. In the liver, phosphorylase a, t and the ratios were increased upon arousal (calculated per unit of wet weight and per mg N). Epinephrine treatment was ineffective in the torpid hibernating bats, but in aroused bats, it decreased muscle and liver glycogen but increased muscle phosphorylase activity ratios only slightly. Histamine was ineffective in the aroused bats. Stimulating aroused bats to fly for short periods consistently resulted in lower muscle glycogen levels and in no change in muscle phosphorylase activity ratios. It is concluded that a) at least part of the increased muscle glycogen in the aroused bats comes from the liver, b) the changes in glycogen levels and phosphorylase activity are in some manner related and c) liver phosphorylase changes upon arousal, unlike that in muscle phosphorylase, involves an increase in total enzyme potential.

Skeletal muscle glycogen phosphorylase is irreversibly inhibited by mercury: Molecular, cellular and kinetic aspects

FEBS Letters ◽  
2013 ◽  
Vol 588 (1) ◽  
pp. 138-142 ◽  
Author(s):  
Ximing Xu ◽  
Cécile Mathieu ◽  
Solène Emmanuelle Boitard ◽  
Julien Dairou ◽  
Jean-Marie Dupret ◽  
...  
Keyword(s):  
Skeletal Muscle ◽  
Muscle Glycogen ◽  
Glycogen Phosphorylase ◽  
Skeletal Muscle Glycogen

Fish muscle glycogen phosphorylase

1968 ◽  
Vol 46 (5) ◽  
pp. 423-432 ◽  
Author(s):  
M. Yamamoto
Keyword(s):  
Skeletal Muscle ◽  
Glycogen Phosphorylase ◽  
Active Form ◽  
Maximal Activity ◽  
Fish Muscle ◽  
Salmo Gairdneri ◽  
Rabbit Muscle ◽  
Muscle Phosphorylase

Glycogen phosphorylase b was purified 70- to 90-fold from skeletal muscle of rainbow trout (Salmo gairdneri). The purified enzyme exhibited maximal activity near pH 6.8 at 37°. Of several 5′-nucleotides tested, only 5′-AMP caused stimulation of phosphorylase b. The Km value for glucose-1-phosphate was 10–15 mM, and for 5′-AMP, 0.2–0.4 mM. Glucose (25 mM) and ATP (5 mM) were both inhibitory, but glucose-6-phosphate (5 mM) had no effect. Inactive trout muscle phosphorylase was converted to the active form in vivo by subjecting a fish to physical exercise. The conversion of fish muscle phosphorylase b to a was also catalyzed in vitro with purified rabbit muscle phosphorylase b kinase in the presence of ATP and Mg++. Evidence is presented to indicate the presence of phosphorylase b kinase and phosphorylase phosphatase in trout skeletal muscle.

Sign in / Sign up

Export Citation Format

Share Document