Myophosphorylase
| phosphorylase, glycogen; muscle (McArdle syndrome, glycogen storage disease type V) | |
|---|---|
 Myophosphorylase[1] | |
| Identifiers | |
| Symbol | PYGM |
| Entrez | 5837 |
| HUGO | 9726 |
| OMIM | 608455 |
| RefSeq | NM_005609 |
| UniProt | P11217 |
| Other data | |
| EC number | 2.4.1.1 |
| Locus | Chr. 11 q12-q13.2 |
Myophosphorylase is the muscle isoform of the enzyme glycogen phosphorylase. This enzyme helps break down glycogen (a form of stored carbohydrate) into glucose-1-phosphate (not glucose), so that it can be utilized within the muscle cell.
Clinical significance
A deficiency is associated with Glycogen storage disease type V, also known as "McArdle's Syndrome".
A case study suggested that a deficiency in myophosphorylase may be linked with cognitive impairment. Besides muscle, this isoform is present in astrocytes, where it plays a key role in neural energy metabolism. A 55-year-old woman with McArdle disease has expressed cognitive impairment with bilateral dysfunction of prefrontal and frontal cortex. Further studies are needed to assess the validity of this claim.[2]
References
- ↑ "RCSB Protein Data Bank - Structure Summary for 3MSC - Glycogen phosphorylase complexed with 2-nitrobenzaldehyde-4-(beta-D-glucopyranosyl)-thiosemicarbazone".
- ↑ Mancuso M, Orsucci D, Volterrani D, Siciliano G (March 2011). "Cognitive impairment and McArdle disease: Is there a link?". Neuromuscul Disord. 21 (5): 356–8. doi:10.1016/j.nmd.2011.02.013. PMID 21382715.
External links
- Myophosphorylase at the US National Library of Medicine Medical Subject Headings (MeSH)