AMP-activated protein kinase complex (AMPK)

AMP-activated protein kinase (AMPK) is a heterotrimeric enzyme complex consisting of a catalytic alpha subunit and regulatory beta and gamma subunits (Source: UniProt P54646). It functions as a central energy sensor and "metabolic master switch" that maintains cellular energy homeostasis by monitoring the AMP/ATP ratio (Source: StatPearls, AMPK). Upon activation by low energy levels, AMPK promotes catabolic pathways such as glucose uptake and fatty acid oxidation to generate ATP, while simultaneously suppressing energy-consuming anabolic processes like lipid and protein synthesis (Source: PubMed, PMID: 22451020). This regulatory role makes AMPK a significant therapeutic target for metabolic diseases, including type 2 diabetes, obesity, and non-alcoholic fatty liver disease (Source: PubMed, PMID: 27637068). Beyond metabolism, AMPK influences cell growth, autophagy, and mitochondrial biogenesis, and its modulation is being explored in oncology and cardiovascular research. Drugs like metformin activate AMPK indirectly, while newer small molecules target specific subunits for direct allosteric activation (Source: Nature Reviews Drug Discovery, PMID: 30610213).

Other names

5'-AMP-activated protein kinaseAdenosine monophosphate-activated protein kinasePRKAMetabolic master switchHMG-CoA reductase kinase

AMPK is activated by an increase in the cellular AMP:ATP or ADP:ATP ratios, which leads to the phosphorylation of the alpha subunit at Thr172 by upstream kinases like LKB1. Drugs can activate AMPK indirectly by inhibiting mitochondrial respiration (e.g., metformin) or directly by binding to the Allosteric Drug and Metabolite (ADaM) site located at the interface between the alpha and beta subunits (Source: PubMed, PMID: 30610213).