AMP kinase as an energy sensor in eukaryotic cells

Abstract

  The AMP-activated kinase (AMPK) is an evolutionarily conserved metabolic sensor, which maintaines cellular energy homeostasis. Homologs of AMPK are found in all eukaryotic animals, sucrose nonfermenting 1(SNF1) in yeast, snf1-related kinase 1 (SnRK1) in plants, AMP-activated kinase (AAK) in worms, and AMPK in flies. AMPK is a heterotrimer consisting of α-catalitic subunit, β and γ-regulatory subunits. AMPK is activated by starvation, the depletion of energy source and some stresses followed by enhancement of energy producing catabolic reactions and suppression of energy consuming anabolic reactions. Historically, activation of AMPK was believed to be regulated by allosteric binding of AMP and ATP at γ-regulatory subunits. However, recent reports suggest that AMPK is regulated by binding of not only AMP and ATP, but also ADP.
  In this review, we focused on the structure, function and regulation of AMPK in representative eukaryotic animals and also describes multiple metabolic regulations induced by AMPK activation.