ID:LST8_HUMAN DESCRIPTION: RecName: Full=Target of rapamycin complex subunit LST8; Short=TORC subunit LST8; AltName: Full=G protein beta subunit-like; Short=Gable; Short=Protein GbetaL; AltName: Full=Mammalian lethal with SEC13 protein 8; Short=mLST8; FUNCTION: Subunit of both mTORC1 and mTORC2, which regulates cell growth and survival in response to nutrient and hormonal signals. 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. Within mTORC1, LST8 interacts directly with MTOR and enhances its kinase activity. In nutrient- poor conditions, stabilizes the MTOR-RPTOR interaction and favors RPTOR-mediated inhibition of MTOR activity. mTORC2 is also activated by growth factors, but seems to be nutrient-insensitive. mTORC2 seems to function upstream of Rho GTPases to regulate the actin cytoskeleton, probably by activating one or more Rho-type guanine nucleotide exchange factors. mTORC2 promotes the serum- induced formation of stress-fibers or F-actin. mTORC2 plays a critical role in AKT1 'Ser-473' phosphorylation, which may facilitate the phosphorylation of the activation loop of AKT1 on 'Thr-308' by PDK1 which is a prerequisite for full activation. mTORC2 regulates the phosphorylation of SGK1 at 'Ser-422'. mTORC2 also modulates the phosphorylation of PRKCA on 'Ser-657'. SUBUNIT: Part of the mammalian target of rapamycin complex 1 (mTORC1) which contains MTOR, MLST8, RPTOR, AKT1S1/PRAS40 and DEPTOR. mTORC1 binds to and is inhibited by FKBP12-rapamycin. Part of the mammalian target of rapamycin complex 2 (mTORC2) which contains MTOR, MLST8, PRR5, RICTOR, MAPKAP1 and DEPTOR. Contrary to mTORC1, mTORC2 does not bind to and is not sensitive to FKBP12- rapamycin. Interacts directly with MTOR and RPTOR. Interacts with RHEB. INTERACTION: P42345:MTOR; NbExp=4; IntAct=EBI-1387471, EBI-359260; Q8N122:RPTOR; NbExp=3; IntAct=EBI-1387471, EBI-1567928; SUBCELLULAR LOCATION: Cytoplasm (By similarity). TISSUE SPECIFICITY: Broadly expressed, with highest levels in skeletal muscle, heart and kidney. SIMILARITY: Belongs to the WD repeat LST8 family. SIMILARITY: Contains 7 WD repeats. SEQUENCE CAUTION: Sequence=EAW85539.1; Type=Erroneous gene model prediction;
The RNAfold program from the Vienna RNA Package is used to perform the secondary structure predictions and folding calculations. The estimated folding energy is in kcal/mol. The more negative the energy, the more secondary structure the RNA is likely to have.
ModBase Predicted Comparative 3D Structure on Q9BVC4
Front
Top
Side
The pictures above may be empty if there is no ModBase structure for the protein. The ModBase structure frequently covers just a fragment of the protein. You may be asked to log onto ModBase the first time you click on the pictures. It is simplest after logging in to just click on the picture again to get to the specific info on that model.
Orthologous Genes in Other Species
Orthologies between human, mouse, and rat are computed by taking the best BLASTP hit, and filtering out non-syntenic hits. For more distant species reciprocal-best BLASTP hits are used. Note that the absence of an ortholog in the table below may reflect incomplete annotations in the other species rather than a true absence of the orthologous gene.
Gene Ontology (GO) Annotations with Structured Vocabulary
Molecular Function: GO:0005515 protein binding GO:0043539 protein serine/threonine kinase activator activity
Biological Process: GO:0007050 cell cycle arrest GO:0016241 regulation of macroautophagy GO:0030838 positive regulation of actin filament polymerization GO:0031929 TOR signaling GO:0032008 positive regulation of TOR signaling GO:0032148 activation of protein kinase B activity GO:0032956 regulation of actin cytoskeleton organization GO:0038202 TORC1 signaling GO:0043087 regulation of GTPase activity GO:0050731 positive regulation of peptidyl-tyrosine phosphorylation GO:0071902 positive regulation of protein serine/threonine kinase activity GO:1900034 regulation of cellular response to heat
US Server
Sequence and Links to Tools and Databases 
Common Gene Haplotype Alleles 
