Mammalian target of rapamycin (mTOR)-dependent protein synthesis signaling pathway (mTOR pathway)

The mTOR-dependent protein synthesis signaling pathway is a critical cellular mechanism that regulates protein synthesis and cell growth. mTOR functions as a serine/threonine protein kinase and is the catalytic subunit of two distinct complexes, mTORC1 and mTORC2, which localize to different subcellular compartments. Upon activation by RHEB, mTORC1 localizes to the Ragulator-Rag complex on the lysosome surface where it becomes active in the presence of sufficient amino acids. The pathway is activated by amino acids, insulin, growth factors, mechanical stimuli, and phosphatidic acid, and inhibited by nutrient/energy deficiency and rapamycin (mTORC1 specific). It plays crucial roles in protein synthesis regulation, ribosome biogenesis, cell growth, mitochondrial metabolism, and cytoskeletal organization. Dysregulation is implicated in various conditions including metabolic disorders, muscle wasting, cellular senescence, and obesity, making it a significant target for therapeutic interventions.

Other names

mTOR pathway

Rapamycin (Sirolimus) inhibits mTORC1, resulting in the suppression of cellular senescence. It has a more complex effect on mTORC2, inhibiting it only in certain cell types under prolonged exposure.