AMPK activation is primarily triggered by an increase in the AMP/ATP ratio, which occurs during cellular energy stress. When ATP levels drop, AMP levels rise, leading to the activation of AMPK. This activation involves the phosphorylation of the AMPK alpha subunit at a specific threonine residue. Various upstream kinases, such as LKB1 and CAMKK2, are involved in this phosphorylation process.
