P70S6 kinase phosphorylates AMPK on serine 491 to mediate leptin's effect on food intake Academic Article uri icon


MeSH Major

  • Adenylate Kinase
  • Eating
  • Leptin
  • Ribosomal Protein S6 Kinases, 70-kDa
  • Serine


  • The PI3K-AKT, mTOR-p70S6 kinase and AMPK pathways play distinct and critical roles in metabolic regulation. Each pathway is necessary for leptin's anorexigenic effects in the hypothalamus. Here we show that these pathways converge in an integrated phosphorylation cascade to mediate leptin action in the hypothalamus. We identify serine(491) on α2AMPK as the site of convergence and show that p70S6 kinase forms a complex with α2AMPK, resulting in phosphorylation on serine(491). Blocking α2AMPK-serine(491) phosphorylation increases hypothalamic AMPK activity, food intake, and body weight. Serine(491) phosphorylation is necessary for leptin's effects on hypothalamic α2AMPK activity, neuropeptide expression, food intake, and body weight. These results identify an inhibitory AMPK kinase, p70S6 kinase, and demonstrate that AMPK is a substrate for mTOR-p70S6 kinase. This discovery has broad biologic implications since mTOR-p70S6 kinase and AMPK have multiple, fundamental and generally opposing cellular effects that regulate metabolism, cell growth, and development.

publication date

  • July 3, 2012



  • Academic Article



  • eng

PubMed Central ID

  • PMC3407689

Digital Object Identifier (DOI)

  • 10.1016/j.cmet.2012.05.010

PubMed ID

  • 22727014

Additional Document Info

start page

  • 104

end page

  • 12


  • 16


  • 1