AMPK
Category: Pathways · Last updated
AMPK (5'-AMP-activated protein kinase) is a heterotrimeric serine/threonine kinase that senses cellular energy state through the ratio of AMP to ATP and orchestrates catabolic responses when energy is low.
Activation
AMPK is activated when:
- Cellular AMP rises (energy stress, glucose deprivation, hypoxia, exercise)
- The upstream kinase LKB1 phosphorylates the AMPK α-subunit Thr172
- Other upstream kinases (CaMKKβ) phosphorylate the same site in calcium-driven contexts
Downstream effects
Active AMPK:
- Stimulates glucose uptake (GLUT4 translocation in skeletal muscle, independent of insulin)
- Stimulates fatty-acid oxidation via inhibition of acetyl-CoA carboxylase
- Inhibits anabolic processes (mTOR, lipid synthesis, protein synthesis)
- Promotes mitochondrial biogenesis via PGC-1α
- Promotes autophagy via ULK1 phosphorylation
Relevance to research peptides
- MOTS-c · the mitochondrial-derived peptide activates AMPK in skeletal muscle and is one of the few endogenous peptides characterized as a direct AMPK activator (Lee et al., Cell Metab 2015; PMID 25738459)
See also
References
- Hardie DG. "AMPK — sensing energy while talking to other signaling pathways." Cell Metab. 2014;20(6):939-52.