Mechanistic target of rapamycin complex 1 (mTORC1) (mTORC1)

Mechanistic target of rapamycin complex 1 (mTORC1) is a highly conserved multi-protein serine/threonine kinase complex that functions as a master regulator of cellular metabolism and growth (Saxton & Sabatini, 2017, PubMed: 28235197). It integrates signals from growth factors, energy status, and nutrient availability, particularly amino acids like tryptophan (Laplante & Sabatini, 2012, PubMed: 21620004). In the IDO/TDO pathway, the depletion of tryptophan by indoleamine 2,3-dioxygenase (IDO) or tryptophan 2,3-dioxygenase (TDO) leads to the suppression of mTORC1 activity in T-cells, contributing to an immunosuppressive environment that allows tumors to evade the immune system (Munn & Mellor, 2013, PubMed: 23517318). Pharmacological modulation of mTORC1 is a cornerstone in treating various cancers and preventing organ transplant rejection. However, its central role in systemic metabolism and immunity leads to significant side effects such as metabolic disturbances and increased infection risk (StatPearls, NBK537184).

Other names

Mammalian target of rapamycin complex 1mTOR Complex 1RAptor-mTOR complexFK506-binding protein 12-rapamycin-associated protein 1 complex

mTORC1 is targeted by rapalogs (e.g., sirolimus) which act as allosteric inhibitors by binding to FKBP12 to sterically block substrate access to the kinase, and by second-generation mTOR inhibitors (TORKis) that compete with ATP at the catalytic site of the kinase domain (Saxton & Sabatini, 2017, PubMed: 28235197).