Gene

Cell biology

mTORC1

Mechanistic target of rapamycin

Philosophy

RHEB

RPTOR

Biology

Cell growth

Signal transduction

Cancer research

Computational biology

Genetics

Environmental ethics

Effector

Cell fate determination

Transcription factor

mTORC2

PI3K/AKT/mTOR pathway

Immunological Reviews

The evolutionarily conserved serine/threonine kinase mTOR (mechanistic target of rapamycin) forms the distinct protein complexes mTORC1 and mTORC2 and integrates signals from the environment to coordinate downstream signaling events and various cellular processes. T cells rely on mTOR activity for their development and to establish their homeostasis and functional fitness. Here, we review recent progress in our understanding of the upstream signaling and downstream targets of mTOR. We also provide an updated overview of the roles of mTOR in T‐cell development, homeostasis, activation, and effector‐cell fate decisions, as well as its important impacts on the suppressive activity of regulatory T cells. Moreover, we summarize the emerging roles of mTOR in T‐cell exhaustion and transdifferentiation. A better understanding of the contribution of mTOR to T‐cell fate decisions will ultimately aid in the therapeutic targeting of mTOR in human disease.

mTOR signaling at the crossroads of environmental signals and T‐cell fate decisions