Glucose-6-phosphatase catalytic subunit alpha (G6Pase-alpha) (G6PC1)

Glucose-6-phosphatase catalytic subunit alpha (G6Pase-α) is a critical enzyme anchored in the endoplasmic reticulum membrane, predominantly active in the liver, kidneys, and intestinal mucosa (UniProt P35575). It performs the final step of both gluconeogenesis and glycogenolysis by hydrolyzing glucose-6-phosphate into free glucose and inorganic phosphate, which is then released into the bloodstream (PubMed PMID: 30119041). This enzymatic activity is vital for maintaining systemic glucose homeostasis during periods of fasting. Deficiency of G6Pase-α, caused by mutations in the G6PC gene, results in Glycogen Storage Disease Type Ia (GSD Ia), a condition marked by life-threatening hypoglycemia, hepatomegaly, and long-term risks of hepatic adenomas and renal failure (NIH GARD). Current therapeutic development, such as DTX401, focuses on adeno-associated virus (AAV) mediated gene therapy to provide a functional copy of the G6PC gene to the liver (Ultragenyx). Traditional management relies on strict dietary control with cornstarch to prevent hypoglycemia, but gene therapy offers the potential for endogenous glucose regulation.

Other names

G6Pase-alphaG6PCGlucose-6-phosphatase alphavon Gierke disease proteinG6Pase

Gene replacement therapy aims to restore functional enzyme activity in the liver to normalize glucose production; experimental inhibitors target the enzyme to reduce hepatic glucose output in type 2 diabetes.