GTP-binding protein Rheb (Ras homolog enriched in brain)
1_MPQSK 6_ SRKIA 11_ ILGYR 16_ SVGKS 21_ SLTIQ 26_ FVEGQ 31_ FVDSY 36_ DPTIE 41_ NTFTK 46_ LITVN 51_ GQEYH 56_ LQLVD 61_ TAGQD 66_ EYSIF 71_ PQTYS 76_ IDING 81_ YILVY 86_ SVTSI 91_ KSFEV 96_ IKVIH 101_ GKLLD 106_ MVGKV 111_ QIPIM 116_ LVGNK 121_ KDLHM 126_ ERVIS 131_ YEEGK 136_ ALAES 141_ WNAAF 146_ LESSA 151_ KENQT 156_ AVDVF 161_ RRIIL 166_ EAEKM 171_ DGAAS 176_QGKSS
1: Small GTPase that acts as an allosteric activator of the canonical mTORC1 complex, an evolutionarily conserved central nutrient sensor that stimulates anabolic reactions and macromolecule biosynthesis to promote cellular biomass generation and growth (PubMed:12172553, PubMed:12271141, PubMed:12842888, PubMed:12869586, PubMed:12906785, PubMed:15340059, PubMed:15854902, PubMed:16098514, PubMed:20381137, PubMed:22819219, PubMed:24529379, PubMed:29416044, PubMed:32470140, PubMed:33157014, PubMed:25816988). In response to nutrients, growth factors or amino acids, specifically activates the protein kinase activity of MTOR, the catalytic component of the mTORC1 complex: acts by causing a conformational change that allows the alignment of residues in the active site of MTOR, thereby enhancing the phosphorylation of ribosomal protein S6 kinase (RPS6KB1 and RPS6KB2) and EIF4EBP1 (4E-BP1) (PubMed:29236692, PubMed:33157014). RHEB is also required for localization of the TSC-TBC complex to lysosomal membranes (PubMed:24529379). In response to starvation, RHEB is inactivated by the TSC-TBC complex, preventing activation of mTORC1 (PubMed:24529379, PubMed:33157014). Has low intrinsic GTPase activity (PubMed:15340059)