This gene is a member of the Ser/Thr protein kinase family and encodes a protein with one protein kinase domain and two calmodulin-binding domains. This protein is the catalytic member of a 16 subunit protein kinase complex which contains equimolar ratios of 4 subunit types. The complex is a crucial glycogenolytic regulatory enzyme. This gene has two pseudogenes at chromosome 7q11.21 and one at chromosome 11p11.12. Multiple transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, May 2012],catalytic activity:2 ATP + phosphorylase b = 2 ADP + phosphorylase a.,domain:The two calmodulin-binding domains appear to act in concert to bind a single molecule of calmodulin and are pseudosubstrate/autoinhibitory domains.,function:Phosphorylase b kinase catalyzes the phosphorylation of serine in certain substrates, including troponin I.,similarity:Belongs to the protein kinase superfamily.,similarity:Belongs to the protein kinase superfamily. CAMK Ser/Thr protein kinase family.,similarity:Contains 1 protein kinase domain.,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.,
