5'-AMP-activated protein kinase alpha-2 beta-1 gamma-1 heterotrimer (AMPK α2β1γ1)

The AMPK α2β1γ1 heterotrimer is a key isoform of the 5'-AMP-activated protein kinase, a central energy-sensing enzyme found in all eukaryotic cells [1, 12]. It is composed of a catalytic α2 subunit, a scaffolding β1 subunit, and a regulatory γ1 subunit, which together coordinate the cellular response to energy stress [1, 6]. When the ratio of AMP or ADP to ATP increases, the γ1 subunit binds these nucleotides, leading to allosteric activation and protection of the α2 subunit's activation loop (Thr172) from dephosphorylation [4, 8]. Once active, the complex restores energy balance by stimulating catabolic processes like glucose uptake and fatty acid oxidation while suppressing anabolic pathways such as cholesterol and protein synthesis [3, 9]. This heterotrimer is a primary target for metabolic drugs like metformin and various direct activators under development for treating type 2 diabetes and obesity [2, 10]. However, therapeutic modulation must be carefully managed due to potential side effects like cardiac hypertrophy and the complex role of AMPK in supporting the survival of established cancer cells [2, 10].

Other names

PRKAA2-PRKAB1-PRKAG1 complexAMPK alpha-2 beta-1 gamma-1AMP-activated protein kinase alpha-2 beta-1 gamma-1AMPK2

Allosteric activation by AMP/ADP or small molecules at the ADaM site, protection against Thr172 dephosphorylation, and phosphorylation of downstream metabolic targets to restore energy balance.