Prkab2 Knockout mouse models

Prkab2 encodes AMPK beta2, orthologous to human PRKAB2, a regulatory subunit that assembles obligate heterotrimers with an alpha catalytic and a gamma nucleotide-sensing subunit, contributing both the bridging module and a carbohydrate-binding domain with higher glycogen affinity than beta1, which localizes the kinase to glycogen particles in skeletal muscle and heart. This distribution makes beta2 the dominant scaffold for contraction and ischemia-driven AMPK signaling and for the muscle response to AICAR and exercise, and it accounts for reduced total muscle AMPK activity in beta2 null animals despite intact beta1. Conditional deletion in muscle or cardiomyocytes therefore addresses substrate delivery and glucose uptake, while a carbohydrate-binding module mutant separates glycogen tethering from trimer assembly, a distinction no null can make. Because beta1 partially replaces beta2 in trimer formation, plan compound Prkab1 and Prkab2 conditional genetics before attributing a metabolic phenotype to loss of one beta isoform.

Prkab2 null animals are straightforward to genotype and phenotype when survival is acceptable. They remain a standard background for pharmacology, biomarker, and rescue studies.