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MS
rate-limiting unreviewed

Glycogen phosphorylase

1 reactions · 1 pathways

Clinical / pharmacological. McArdle disease (GSD V, muscle); Hers disease (GSD VI, liver)

What it does, reaction by reaction

1 reactions

Glycogenolysis (Glycogen Breakdown) Carbohydrate Metabolism · Cytosol + ER (liver)

step 1 Irreversible/directional rate-limiting

Glycogen(n) + Pi → glycogen(n−1) + glucose-1-phosphate

Converts Glycogen(n) Pi into Glycogen(n-1) Glucose-1-phosphate

› Notes

Glycogen phosphorylase uses inorganic phosphate (Pi) and the cofactor pyridoxal phosphate (PLP; vitamin B6) to phosphorolyze successive alpha(1→4) bonds at nonreducing ends. It stops four residues before an alpha(1→6) branch (a limit dextrin); this is the principal rate-limiting step and conserves the bond energy in glucose-1-phosphate rather than using ATP.

Showing all 1 reactions.

What accelerates and inhibits it

Regulation is pathway-specific, so each context is listed separately

1 entries

Glycogenolysis (Glycogen Breakdown)

Accelerated by

Phosphorylation by phosphorylase kinase; AMP in muscle; Ca2+ indirectly through calmodulin on phosphorylase kinase

Inhibited by

ATP and glucose-6-phosphate in muscle; glucose in liver promotes inactivation

Hormonal control

Glucagon activates liver phosphorylase through cAMP/protein kinase A; epinephrine activates liver and muscle pathways; insulin promotes dephosphorylation/inactivation

Recent literature

Europe PMC · fetched just now · sorted by publication date

  1. 1
    Targeting ROAM1 with UDP-GlcNAc nanosheets selective activates lysosomal AMPK to resolve metabolic dysfunction-associated steatotic liver disease.

    Zhu J, Sun T, Wei F, Wang D, Liu F, Chen D, Liu X, Wang C, Deng S, Yang Y, Xiong Y, Xiang H, Li J, Li S, Ma W… · 2026-07-12

    open access unreviewed
  2. 2
  3. 3
  4. 4
    Hijacking and subversion of macrophage antiviral functions by viruses.

    Xu Z, Shi F, Han J, Zhou L, Yang H. · 2026-06-29

    open access unreviewed
  5. 5
    The impact of (poly)phenol-rich sugarcane extract intervention on markers of gastrointestinal integrity and systemic inflammation in response to exertional-heat stress.

    Hewawansa UHAJ, Henningsen K, Vilela Silva Daniel N, In S, Sugay G, Houghton MJ, Barber E, Williamson G, Cost… · 2026-06-18

    open access unreviewed
  6. 6
    Carbohydrate supplementation for endurance exercise in the heat: a systematic review with practical recommendations.

    Salame A, Brown D, Oueijan K, McCullough D. · 2026-05-09

    open access unreviewed
  7. 7
  8. 8
    Advances in calcium signalling research for the diagnosis and treatment of depression.

    Li L, Yao M, Meng J, Zhong Z, Nan N, Kazemi AH, Guo J, Liu C, Jiang Y. · 2026-03-05

    cited 5× open access unreviewed
  9. 9
    [Retracted] PYGB siRNA inhibits the cell proliferation of human osteosarcoma cell lines.

    Zhang S, Zhou Y, Zha Y, Yang Y, Wang L, Li J, Jin W. · 2026-09-11

    open access unreviewed
  10. 10
    Ingenane diterpenoids with anti-inflammatory activity from the whole plants of Euphorbia peplus.

    Liu Y, Xu Y, Sun D, Ren L, Huang S, Chen L, Li H. · 2026-07-02

    cited 1× unreviewed

External claims. These come from an index outside this database and are not checked against it. Treat them as leads.