PHKA1/2 Polyclonal Antibody

disease:Defects in PHKA1 are the cause of glycogen storage disease type 9D (GSD9D) [MIM:300559]; also known as X-linked muscle glycogenosis. GSD9D is a metabolic disorder characterized by slowly progressive, predominantly distal muscle weakness and atrophy. Clinical features include exercise intolerance with early fatiguability, pain, cramps and occasionally myoglobinuria.,enzyme regulation:By phosphorylation of various serine residues. Allosteric regulation by calcium.,function:Phosphorylase b kinase catalyzes the phosphorylation of serine in certain substrates, including troponin I. The alpha chain may bind calmodulin.,pathway:Glycan biosynthesis; glycogen metabolism.,similarity:Belongs to the phosphorylase b kinase regulatory chain family.,subunit:Polymer of 16 chains, four each of alpha, beta, gamma, and delta. Alpha and beta are regulatory chains, gamma is the catalytic chain, and delta is calmodulin.,tissue specificity:Muscle specific. Isoform 1 is predominant in vastus lateralis muscle. Isoform 2 predominates slightly in heart, and it predominates clearly in the other tissues tested.,