Phosphorylase b kinase regulatory subunit alpha, skeletal muscle isoform is an enzyme that in humans is encoded by the PHKA1gene.
The PHKA1 gene encodes the alpha subunit of muscle phosphorylase kinase (EC 220.127.116.11), a key regulatory enzyme of glycogen metabolism. Phosphorylase kinase consists of 4 copies of an alpha-beta-gamma-delta tetramer. The alpha, beta (PHKB; MIM 172490), and gamma (PHKG1; MIM 172470 and PHKG2; MIM 172471) subunits have several isoforms; the delta subunit is calmodulin (CALM1; MIM 114180). PHKA2 (MIM 306000) encodes the alpha subunit of liver-specific phosphorylase kinase and is also located on the X chromosome.[supplied by OMIM]
Wehner M, Clemens PR, Engel AG, Kilimann MW (1995). "Human muscle glycogenosis due to phosphorylase kinase deficiency associated with a nonsense mutation in the muscle isoform of the alpha subunit.". Hum. Mol. Genet.3 (11): 1983–7. PMID7874115.
Wüllrich A, Hamacher C, Schneider A, Kilimann MW (1993). "The multiphosphorylation domain of the phosphorylase kinase alpha M and alpha L subunits is a hotspot of differential mRNA processing and of molecular evolution.". J. Biol. Chem.268 (31): 23208–14. PMID8226841.
Burwinkel B, Hu B, Schroers A, et al. (2004). "Muscle glycogenosis with low phosphorylase kinase activity: mutations in PHKA1, PHKG1 or six other candidate genes explain only a minority of cases.". Eur. J. Hum. Genet.11 (7): 516–26. doi:10.1038/sj.ejhg.5200996. PMID12825073.