IndraLab

"Mtorc1 promotes protein synthesis by phosphorylating the eukaryotic initiation factor 4e (eif4e)- binding protein 1 (4e-bp1) and the p70 ribosomal s6 kinase 1 (s6k1). In vitro activation of p70alfa by mtor-catalyzed phosphorylation involving p70alfa thr-412. Mtor-catalyzed p70alfa phosphorylation in vitro is accompanied by a substantial restoration in p70alfa kinase activity toward its physiologic substrate, the 40 s ribosomal protein s6. In response to insulin and nutrients, mtorc1, consisting of mtor, raptor (regulatory-associated protein of mtor), and mlst8, is activated and phosphorylates eukaryotic initiation factor 4e-binding protein (4ebp) and p70 s6 kinase to promote protein synthesis and cell size."

"S6K1 is a positive regulator of protein synthesis, and its activity is induced by mTOR-mediated phosphorylation."

"Collectively, these results indicate that Arg, Leu, and Gln act coordinately to stimulate proliferation of pTr cells through activation of the MTOR-RPS6K-RPS6-EIF4EBP1 signal transduction pathway"

"Mtorc1 promotes protein synthesis by phosphorylating the eukaryotic initiation factor 4e (eif4e)- binding protein 1 (4e-bp1) and the p70 ribosomal s6 kinase 1 (s6k1). In vitro activation of p70alfa by mtor-catalyzed phosphorylation involving p70alfa thr-412. Mtor-catalyzed p70alfa phosphorylation in vitro is accompanied by a substantial restoration in p70alfa kinase activity toward its physiologic substrate, the 40 s ribosomal protein s6. In response to insulin and nutrients, mtorc1, consisting of mtor, raptor (regulatory-associated protein of mtor), and mlst8, is activated and phosphorylates eukaryotic initiation factor 4e-binding protein (4ebp) and p70 s6 kinase to promote protein synthesis and cell size."

"S6 kinases are under the control of the PI3K relative, mammalian Target Of Rapamycin (mTOR), which may serve an additional function as a checkpoint for amino acid availability."

"A regulatory link between p70s6k and pkb was demonstrated, as pdk1 was found to selectively phosphorylate p70s6k at thr229. More importantly, pdk1 activated p70s6k in vitro and in vivo, whereas the catalytically inactive pdk1 blocked insulin-induced activation of p70s6k. One of the most studied events controlled by ptdins(3,4,5)p3, comprises the activation of a of agc family protein kinases, including isoforms of protein kinase b (pkb)/akt, p70 ribosomal s6 kinase (s6k), serum- and glucocorticoid-induced protein kinase (sgk) and protein kinase c (pkc), which play crucial roles in regulating physiological processes relevant to metabolism, growth, proliferation and survival. Here, we review recent biochemical, genetic and structural studies on the 3-phosphoinositide-dependent protein kinase-1 (pdk1), which phosphorylates and activates the agc kinase members regulated by pi 3-kinase. We also discuss whether inhibitors of pdk1 might have chemotherapeutic potential in the treatment of cancers in which the pdk1-regulated agc kinases are constitutively activated. Phosphorylation and activation of p70s6k by pdk1."

"A regulatory link between p70s6k and pkb was demonstrated, as pdk1 was found to selectively phosphorylate p70s6k at thr229. More importantly, pdk1 activated p70s6k in vitro and in vivo, whereas the catalytically inactive pdk1 blocked insulin-induced activation of p70s6k. one of the most studied signalling events controlled by ptdins(3,4,5)p3, comprises the activation of a group of agc family protein kinases, including isoforms of protein kinase b (pkb)/akt, p70 ribosomal s6 kinase (s6k), serum- and glucocorticoid-induced protein kinase (sgk) and protein kinase c (pkc), which play crucial roles in regulating physiological processes relevant to metabolism, growth, proliferation and survival. Here, we review recent biochemical, genetic and structural studies on the 3-phosphoinositide-dependent protein kinase-1 (pdk1), which phosphorylates and activates the agc kinase members regulated by pi 3-kinase. We also discuss whether inhibitors of pdk1 might have chemotherapeutic potential in the treatment of cancers in which the pdk1-regulated agc kinases are constitutively activated."

"Mtorc1 promotes protein synthesis by phosphorylating the eukaryotic initiation factor 4e (eif4e)- binding protein 1 (4e-bp1) and the p70 ribosomal s6 kinase 1 (s6k1). In vitro activation of p70alfa by mtor-catalyzed phosphorylation involving p70alfa thr-412. Mtor-catalyzed p70alfa phosphorylation in vitro is accompanied by a substantial restoration in p70alfa kinase activity toward its physiologic substrate, the 40 s ribosomal protein s6. in response to insulin and nutrients, mtorc1, consisting of mtor, raptor (regulatory-associated protein of mtor), and mlst8, is activated and phosphorylates eukaryotic initiation factor 4e-binding protein (4ebp) and p70 s6 kinase to promote protein synthesis and cell size."

"mTORC1 catalyzes the phosphorylation of eIF4E binding protein-1 (4EBP1, also known as PHAS-I) and p70 S6 kinase 1 (S6K1)Phosphorylation of S6K1 at Thr-389"

"Mtorc1 promotes protein synthesis by phosphorylating the eukaryotic initiation factor 4e (eif4e)- binding protein 1 (4e-bp1) and the p70 ribosomal s6 kinase 1 (s6k1). In vitro activation of p70alfa by mtor-catalyzed phosphorylation involving p70alfa thr-412. Mtor-catalyzed p70alfa phosphorylation in vitro is accompanied by a substantial restoration in p70alfa kinase activity toward its physiologic substrate, the 40 s ribosomal protein s6. In response toinsulinand nutrients, mtorc1, consisting of mtor, raptor (regulatory-associated protein of mtor), and mlst8, is activated and phosphorylates eukaryotic initiation factor 4e-binding protein (4ebp) and p70 s6 kinase to promote protein synthesis and cell size."

"We report here that a mammalian recombinant p70alpha polypeptide, extracted in an inactive form from rapamycin-treated cells, can be directly phosphorylated by the mTOR kinase in vitro predominantly at the rapamycin-sensitive site Thr-412. mTOR-catalyzed p70alpha phosphorylation in vitro is accompanied by a substantial restoration in p70alpha kinase activity toward its physiologic substrate"