A phosphatidylinositol 3-kinase/protein kinase B-independent activation of mammalian target of rapamycin signaling is sufficient to induce skeletal muscle hypertrophy.

ABSTRACT: It has been widely proposed that signaling by mammalian target of rapamycin (mTOR) is both necessary and sufficient for the induction of skeletal muscle hypertrophy. Evidence for this hypothesis is largely based on studies that used stimuli that activate mTOR via a phosphatidylinositol 3-kinase (PI3K)/protein kinase B (PKB)-dependent mechanism. However, the stimulation of signaling by PI3K/PKB also can activate several mTOR-independent growth-promoting events; thus, it is not clear whether signaling by mTOR is permissive, or sufficient, for the induction of hypertrophy. Furthermore, the presumed role of mTOR in hypertrophy is derived from studies that used rapamycin to inhibit mTOR; yet, there is very little direct evidence that mTOR is the rapamycin-sensitive element that confers the hype

SUBMITTER: Goodman CA 

PROVIDER: S-EPMC2938390 | biostudies-literature | 2010 Sep

REPOSITORIES: biostudies-literature