P42346 (MTOR_RAT) Reviewed, UniProtKB/Swiss-Prot
Last modified June 11, 2014. Version 127. History...
Names and origin
|Protein names||Recommended name:|
Serine/threonine-protein kinase mTOR
FK506-binding protein 12-rapamycin complex-associated protein 1
FKBP12-rapamycin complex-associated protein
Mammalian target of rapamycin
Mechanistic target of rapamycin
Rapamycin target protein 1
|Organism||Rattus norvegicus (Rat) [Reference proteome]|
|Taxonomic identifier||10116 [NCBI]|
|Taxonomic lineage||Eukaryota › Metazoa › Chordata › Craniata › Vertebrata › Euteleostomi › Mammalia › Eutheria › Euarchontoglires › Glires › Rodentia › Sciurognathi › Muroidea › Muridae › Murinae › Rattus|
|Sequence length||2549 AA.|
|Protein existence||Evidence at protein level|
General annotation (Comments)
Serine/threonine protein kinase which is a central regulator of cellular metabolism, growth and survival in response to hormones, growth factors, nutrients, energy and stress signals. MTOR directly or indirectly regulates the phosphorylation of at least 800 proteins. Functions as part of 2 structurally and functionally distinct signaling complexes mTORC1 and mTORC2 (mTOR complex 1 and 2). Activated mTORC1 up-regulates protein synthesis by phosphorylating key regulators of mRNA translation and ribosome synthesis. This includes phosphorylation of EIF4EBP1 and release of its inhibition toward the elongation initiation factor 4E (eiF4E). Moreover, phosphorylates and activates RPS6KB1 and RPS6KB2 that promote protein synthesis by modulating the activity of their downstream targets including ribosomal protein S6, eukaryotic translation initiation factor EIF4B, and the inhibitor of translation initiation PDCD4. Stimulates the pyrimidine biosynthesis pathway, both by acute regulation through RPS6KB1-mediated phosphorylation of the biosynthetic enzyme CAD, and delayed regulation, through transcriptional enhancement of the pentose phosphate pathway which produces 5-phosphoribosyl-1-pyrophosphate (PRPP), an allosteric activator of CAD at a later step in synthesis, this function is dependent on the mTORC1 complex. Regulates ribosome synthesis by activating RNA polymerase III-dependent transcription through phosphorylation and inhibition of MAF1 an RNA polymerase III-repressor. In parallel to protein synthesis, also regulates lipid synthesis through SREBF1/SREBP1 and LPIN1. To maintain energy homeostasis mTORC1 may also regulate mitochondrial biogenesis through regulation of PPARGC1A. mTORC1 also negatively regulates autophagy through phosphorylation of ULK1. Under nutrient sufficiency, phosphorylates ULK1 at 'Ser-758', disrupting the interaction with AMPK and preventing activation of ULK1. Also prevents autophagy through phosphorylation of the autophagy inhibitor DAP. mTORC1 exerts a feedback control on upstream growth factor signaling that includes phosphorylation and activation of GRB10 a INSR-dependent signaling suppressor. Among other potential targets mTORC1 may phosphorylate CLIP1 and regulate microtubules. As part of the mTORC2 complex MTOR may regulate other cellular processes including survival and organization of the cytoskeleton. Plays a critical role in the phosphorylation at 'Ser-473' of AKT1, a pro-survival effector of phosphoinositide 3-kinase, facilitating its activation by PDK1. mTORC2 may regulate the actin cytoskeleton, through phosphorylation of PRKCA, PXN and activation of the Rho-type guanine nucleotide exchange factors RHOA and RAC1A or RAC1B. mTORC2 also regulates the phosphorylation of SGK1 at 'Ser-421'. Ref.4
ATP + a protein = ADP + a phosphoprotein.
Activation of mTORC1 by growth factors such as insulin involves AKT1-mediated phosphorylation of TSC1-TSC2, which leads to the activation of the RHEB GTPase a potent activator of the protein kinase activity of mTORC1. Insulin-stimulated and amino acid-dependent phosphorylation at Ser-1261 promotes autophosphorylation and the activation of mTORC1. Activation by amino acids requires relocalization of the mTORC1 complex to lysosomes that is mediated by the Ragulator complex and the Rag GTPases RRAGA, RRAGB, RRAGC and RRAGD. On the other hand, low cellular energy levels can inhibit mTORC1 through activation of PRKAA1 while hypoxia inhibits mTORC1 through a REDD1-dependent mechanism which may also require PRKAA1. The kinase activity of MTOR within the mTORC1 complex is positively regulated by MLST8 and negatively regulated by DEPTOR and AKT1S1. MTOR phosphorylates RPTOR which in turn inhibits mTORC1. MTOR is the target of the immunosuppressive and anti-cancer drug rapamycin which acts in complex with FKBP1A/FKBP12, and specifically inhibits its kinase activity. mTORC2 is also activated by growth factors, but seems to be nutrient-insensitive. It may be regulated by RHEB but in an indirect manner through the PI3K signaling pathway By similarity.
Part of the mammalian target of rapamycin complex 1 (mTORC1) which contains MTOR, MLST8, RPTOR, AKT1S1/PRAS40 and DEPTOR. The mTORC1 complex is a 1 Md obligate dimer of two stoichiometric heterotetramers with overall dimensions of 290 A x 210 A x 135 A. It has a rhomboid shape and a central cavity, the dimeric interfaces are formed by interlocking interactions between the two MTOR and the two RPTOR subunits. the MLST8 subunits forms distal foot-like protuberances, and contacts only one MTOR within the complex, while the small PRAS40 localizes to the midsection of the central core, in close proximity to RPTOR. Part of the mammalian target of rapamycin COmplex 2 (mTORC2) which contains MTOR, MLST8, PRR5, RICTOR, MAPKAP1 and DEPTOR. Interacts with PPAPDC3 and PML. Interacts with PRR5 and RICTOR; the interaction is direct within the mTORC2 complex. Interacts with UBQLN1. Interacts with TTI1 and TELO2. Interacts with CLIP1; phosphorylates and regulates CLIP1. Interacts with NBN By similarity.
Endoplasmic reticulum membrane; Peripheral membrane protein; Cytoplasmic side By similarity. Golgi apparatus membrane; Peripheral membrane protein; Cytoplasmic side By similarity. Mitochondrion outer membrane; Peripheral membrane protein; Cytoplasmic side By similarity. Lysosome By similarity. Cytoplasm By similarity. Nucleus › PML body By similarity. Note: Shuttles between cytoplasm and nucleus. Accumulates in the nucleus in response to hypoxia By similarity. Targeting to lysosomes depends on amino acid availability and RRAGA and RRAGB By similarity.
The kinase domain (PI3K/PI4K) is intrinsically active but has a highly restricted catalytic center By similarity.
The FAT domain forms three discontinuous subdomains of alpha-helical TPR repeats plus a single subdomain of HEAT repeats. The four domains pack sequentially to form a C-shaped a-solenoid that clamps onto the kinase domain By similarity.
Autophosphorylates when part of mTORC1 or mTORC2. Phosphorylation at Ser-1261, Ser-2159 and Thr-2164 promotes autophosphorylation. Phosphorylation in the kinase domain modulates the interactions of MTOR with RPTOR and PRAS40 and leads to increased intrinsic mTORC1 kinase activity By similarity.
Belongs to the PI3/PI4-kinase family.
Contains 1 FAT domain.
Contains 1 FATC domain.
Contains 32 HEAT repeats.
Contains 1 PI3K/PI4K domain.
Contains 16 TPR repeats.
Sequence annotation (Features)
|Feature key||Position(s)||Length||Description||Graphical view||Feature identifier|
|Chain||1 – 2549||2549||Serine/threonine-protein kinase mTOR||PRO_0000088810|
|Repeat||16 – 53||38||HEAT 1|
|Repeat||55 – 99||45||HEAT 2|
|Repeat||100 – 137||38||HEAT 3|
|Repeat||138 – 179||42||HEAT 4|
|Repeat||180 – 220||41||HEAT 5|
|Repeat||222 – 276||55||HEAT 6|
|Repeat||277 – 313||37||HEAT 7|
|Repeat||314 – 364||51||HEAT 8|
|Repeat||365 – 409||45||HEAT 9|
|Repeat||410 – 445||36||HEAT 10|
|Repeat||446 – 494||49||HEAT 11|
|Repeat||495 – 529||35||HEAT 12|
|Repeat||530 – 563||34||HEAT 13|
|Repeat||564 – 596||33||HEAT 14|
|Repeat||597 – 636||40||HEAT 15|
|Repeat||637 – 683||47||HEAT 16|
|Repeat||686 – 724||39||HEAT 17|
|Repeat||727 – 766||40||HEAT 18|
|Repeat||769 – 811||43||HEAT 19|
|Repeat||814 – 853||40||HEAT 20|
|Repeat||857 – 893||37||HEAT 21|
|Repeat||894 – 942||49||HEAT 22|
|Repeat||943 – 988||46||HEAT 23|
|Repeat||989 – 1027||39||HEAT 24|
|Repeat||1029 – 1068||40||HEAT 25|
|Repeat||1069 – 1105||37||HEAT 26|
|Repeat||1106 – 1144||39||HEAT 27|
|Repeat||1145 – 1188||44||HEAT 28|
|Repeat||1189 – 1225||37||HEAT 29|
|Repeat||1226 – 1273||48||HEAT 30|
|Repeat||1274 – 1311||38||HEAT 31|
|Repeat||1312 – 1345||34||HEAT 32|
|Repeat||1346 – 1382||37||TPR 1|
|Domain||1382 – 1982||601||FAT|
|Repeat||1383 – 1408||26||TPR 2|
|Repeat||1409 – 1442||34||TPR 3|
|Repeat||1443 – 1473||31||TPR 4|
|Repeat||1474 – 1507||34||TPR 5|
|Repeat||1508 – 1541||34||TPR 6|
|Repeat||1542 – 1574||33||TPR 7|
|Repeat||1575 – 1614||40||TPR 8|
|Repeat||1615 – 1649||35||TPR 9|
|Repeat||1650 – 1693||44||TPR 10|
|Repeat||1694 – 1731||38||TPR 11|
|Repeat||1732 – 1786||55||TPR 12|
|Repeat||1787 – 1846||60||TPR 13|
|Repeat||1898 – 1930||33||TPR 14|
|Repeat||1931 – 1970||40||TPR 15|
|Repeat||1971 – 2005||35||TPR 16|
|Domain||2182 – 2516||335||PI3K/PI4K|
|Domain||2517 – 2549||33||FATC|
|Region||1 – 651||651||Interaction with NBN By similarity|
|Region||2012 – 2144||133||Sufficient for interaction with the FKBP1A/rapamycin complex By similarity|
|Region||2258 – 2296||39||Interaction with MLST8 By similarity|
Amino acid modifications
|Modified residue||1||1||N-acetylmethionine By similarity|
|Modified residue||567||1||Phosphoserine By similarity|
|Modified residue||1162||1||Phosphothreonine By similarity|
|Modified residue||1218||1||N6-acetyllysine By similarity|
|Modified residue||1261||1||Phosphoserine By similarity|
|Modified residue||2159||1||Phosphoserine By similarity|
|Modified residue||2164||1||Phosphothreonine Ref.5|
|Modified residue||2446||1||Phosphothreonine; by RPS6KB1 By similarity|
|Modified residue||2448||1||Phosphoserine; by RPS6KB1 By similarity|
|Modified residue||2478||1||Phosphoserine By similarity|
|Modified residue||2481||1||Phosphoserine; by autocatalysis By similarity|
|||"Isolation of a protein target of the FKBP12-rapamycin complex in mammalian cells."|
Sabers C.J., Martin M.M., Brunn G.J., Williams J.M., Dumont F.J., Wiederrecht G., Abraham R.T.
J. Biol. Chem. 270:815-822(1995) [PubMed] [Europe PMC] [Abstract]
Cited for: NUCLEOTIDE SEQUENCE [MRNA].
|||"RAFT1: a mammalian protein that binds to FKBP12 in a rapamycin-dependent fashion and is homologous to yeast TORs."|
Sabatini D.M., Erdjument-Bromage H., Lui M., Tempst P., Snyder S.H.
Cell 78:35-43(1994) [PubMed] [Europe PMC] [Abstract]
Cited for: NUCLEOTIDE SEQUENCE [MRNA].
|||Lubec G., Kang S.U., Lubec S.|
Submitted (SEP-2007) to UniProtKB
Cited for: PROTEIN SEQUENCE OF 215-226 AND 533-541, IDENTIFICATION BY MASS SPECTROMETRY.
|||"RAFT1 phosphorylation of the translational regulators p70 S6 kinase and 4E-BP1."|
Burnett P.E., Barrow R.K., Cohen N.A., Snyder S.H., Sabatini D.M.
Proc. Natl. Acad. Sci. U.S.A. 95:1432-1437(1998) [PubMed] [Europe PMC] [Abstract]
Cited for: FUNCTION IN PHOSPHORYLATION OF RPS6KB1 AND EIF4EBP1.
|||"mTOR kinase domain phosphorylation promotes mTORC1 signaling, cell growth, and cell cycle progression."|
Ekim B., Magnuson B., Acosta-Jaquez H.A., Keller J.A., Feener E.P., Fingar D.C.
Mol. Cell. Biol. 31:2787-2801(2011) [PubMed] [Europe PMC] [Abstract]
Cited for: PHOSPHORYLATION AT THR-2164.
|+||Additional computationally mapped references.|
|L37085 mRNA. Translation: AAA65929.1.|
U11681 mRNA. Translation: AAA20091.1.
|RefSeq||NP_063971.1. NM_019906.1. |
3D structure databases
|SMR||P42346. Positions 2015-2114, 2517-2549. |
Protein-protein interaction databases
|BioGrid||248568. 4 interactions.|
|IntAct||P42346. 3 interactions.|
Protocols and materials databases
Genome annotation databases
|Ensembl||ENSRNOT00000014167; ENSRNOP00000014167; ENSRNOG00000009615. |
|UCSC||RGD:68371. rat. |
|RGD||68371. Mtor. |
Gene expression databases
Family and domain databases
|Gene3D||1.10.1070.11. 3 hits. |
220.127.116.11. 1 hit.
18.104.22.168. 4 hits.
22.214.171.124. 2 hits.
|InterPro||IPR011989. ARM-like. |
|Pfam||PF11865. DUF3385. 1 hit. |
PF02259. FAT. 1 hit.
PF02260. FATC. 1 hit.
PF00454. PI3_PI4_kinase. 1 hit.
PF08771. Rapamycin_bind. 1 hit.
|SMART||SM00146. PI3Kc. 1 hit. |
|SUPFAM||SSF47212. SSF47212. 1 hit. |
SSF48371. SSF48371. 5 hits.
SSF56112. SSF56112. 2 hits.
|PROSITE||PS51189. FAT. 1 hit. |
PS51190. FATC. 1 hit.
PS00915. PI3_4_KINASE_1. 1 hit.
PS00916. PI3_4_KINASE_2. 1 hit.
PS50290. PI3_4_KINASE_3. 1 hit.
|Accession||Primary (citable) accession number: P42346|
|Entry status||Reviewed (UniProtKB/Swiss-Prot)|
|Annotation program||Chordata Protein Annotation Program|
Index of protein domains and families