Recombinant human PHKG2 protein

Supplementary information

This supplementary information is collated from multiple sources and compiled automatically.

PHKG2 also known as phosphorylase kinase gamma 2 is a catalytic subunit of the phosphorylase kinase (PhK) enzyme. PHKG2 has a molecular weight of approximately 44 kDa. This enzyme is responsible for the phosphorylation of serine residues in glycogen phosphorylase which is necessary for glycogen breakdown. PHKG2 is expressed mainly in muscle and liver tissues where it plays a role in the regulation of glycogen metabolism.

Biological function summary

Phosphorylase kinase involving PHKG2 is critical for the regulation of glycogenolysis. It forms a complex with other subunits including alpha beta and delta contributing to the full enzymatic activity of PhK. As part of this multi-subunit complex PHKG2 facilitates the conversion of glycogen to glucose-1-phosphate ensuring that energy production meets cellular demands during physical activity or fasting.

Pathways

The glycogenolysis process involving PHKG2 is tightly linked with the cAMP-dependent protein kinase (PKA) signaling pathway. Phosphorylase kinase gets activated by PKA under hormonal control prompting glycogen breakdown and maintaining glucose homeostasis. Additionally PHKG2's activity is connected with the insulin signaling pathway which integrates with its function to regulate carbohydrate metabolism especially relating to its interaction with proteins such as glycogen synthase and protein phosphatase 1.

Mutations in PHKG2 associate with Glycogen Storage Disease Type IX (GSD IX) a disorder characterized by an inability to properly break down glycogen leading to muscle weakness and hepatomegaly. PHKG2's interaction with proteins like alpha-glucosidase also links it to conditions like Pompe disease where glycogen buildup occurs due to deficient enzyme activity. Monitoring and understanding PHKG2's role in these contexts is important for developing therapeutic strategies.