Protein kinase AMP-activated catalytic subunit alpha 2 (AMPKα2)

Protein kinase AMP‑activated catalytic subunit alpha 2 (AMPKα₂) is one of two catalytic isoforms forming part of the heterotrimeric AMP‑activated protein kinase complex. This enzyme acts as a central regulator (“energy sensor”) maintaining cellular energy homeostasis by responding to changes in intracellular ATP/AMP ratios. Upon activation—typically triggered by increased cellular stress or low nutrient states—AMPKα₂ phosphorylates multiple downstream targets involved in catabolic processes that generate ATP while inhibiting anabolic processes consuming ATP. The PRKAA₂ gene encodes this isoform; it is expressed broadly but shows tissue-specific functions distinct from its close homolog AMPKα₁. Dysregulation has been implicated in metabolic diseases such as diabetes and obesity, cardiovascular pathologies, certain cancers where it can promote tumor immune escape via T-cell exhaustion mechanisms, neurodegeneration linked to impaired bioenergetics, and other conditions involving altered cell metabolism.

Other names

AMPK alpha-2 chainAMP-activated protein kinase alpha 2 subunitPRKAA2ACACA kinaseAcetyl-CoA carboxylase kinaseHMGCR kinaseHydroxymethylglutaryl-CoA reductase kinase

Drugs targeting this molecule typically act by one or more of the following mechanisms: – Allosteric activation by mimicking AMP binding to regulatory γ subunits – Indirect activation through upstream kinases that phosphorylate Thr174 on the α‑2 catalytic domain – Inhibition or modulation of downstream targets regulated by AMPK phosphorylation