p150 target of rapamycin (TOR)-scaffold protein ; KIAA1303 ; RAPTOR
Categories
Elisa
Function
Involved in the control of the mammalian target of rapamycin complex 1 (mTORC1) activity which regulates cell growth and survival, and autophagy in response to nutrient and hormonal signals; functions as a scaffold for recruiting mTORC1 substrates. mTORC1 is activated in response to growth factors or amino-acids. Growth factor-stimulated mTORC1 activation involves a AKT1-mediated phosphorylation of TSC1-TSC2, which leads to the activation of the RHEB GTPase that potently activates the protein kinase activity of mTORC1. Amino-acid-signaling to mTORC1 requires its relocalization to the lysosomes mediated by the Ragulator complex and the Rag GTPases. Activated mTORC1 up-regulates protein synthesis by phosphorylating key regulators of mRNA translation and ribosome synthesis. mTORC1 phosphorylates EIF4EBP1 and releases it from inhibiting the elongation initiation factor 4E (eiF4E). mTORC1 phosphorylates and activates S6K1 at 'Thr-389', which then promotes protein synthesis by phosphorylating PDCD4 and targeting it for degradation.
Specificity
Natural and recombinant Human Regulatory-associated protein of mTOR
Subcellular Location
Cytoplasm Lysosome Targeting to lysosomes depends on amino acid availability.
Part of the mammalian target of rapamycin complex 1 (mTORC1) which contains MTOR, MLST8, RPTOR and AKT1S1. mTORC1 binds to and is inhibited by FKBP12-rapamycin. Binds directly to 4EBP1 and RPS6KB1 independently of its association with MTOR. Binds preferentially to poorly or non-phosphorylated forms of EIF4EBP1, and this binding is critical to the ability of MTOR to catalyze phosphorylation. Forms a complex with MTOR under both leucine-rich and -poor conditions. Interacts with ULK1 in a nutrient-dependent manner; the interaction is reduced during starvation. Interacts (when phosphorylated by AMPK) with 14-3-3 protein, leading to inhibit its activity.