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The ragulator along with the Rag GTPases and v-ATPase are a part of an amino acid identifying pathway which are necessary for the localization of the mTORC1 to the lysosomal surface. The ragulator and v-ATPases reside on the lysosomal surface. The Rag GTPases cannot be directly bound to the lysosome because they lack the proteins necessary to bind to the lipid bilayer of the lysosome, so Rag GTPases must instead be anchored to the ragulator. The ragulator is bound to the surface via the V-ATPase The ragulator is a crystalized structure composed of five different subunits; LAMTOR 1, LAMTOR 2, LAMTOR 3, LAMTOR 4, LAMTOR 5. There are two sets of obligate heterodimers in the complex, LAMTOR 2/3 which sits right above LAMTOR 4/5. The LAMTOR 1 dimer does not have the same structure as the other subunits. LAMTOR 1 surrounds most of the two heterodimers, providing structure and keeping the heterodimers in place. When amino acids are present the subunits are folded and positioned in such a way that allows for the Rag-GTPases to be anchored to its primary docking site of LAMTOR 2/3 on the ragulator. The Rag-GTPases consist of two sets of heterodimers; RAGs A/B and RAGs C/D. Before Rag-GTPases can bind to the ragulator, Rag A/B must be GTP loaded via guanine nucleotide exchange factors (GEFs) and RAG C/D must be GDP loaded. Once Rag-GTPases are bound to the regulator complex, the mTORC1 can be translocated to the surface of the lysosome. At the lysosomal surface, the mTORC1 will then bind to Rheb but only if Rheb was first loaded to a GTP via GEFs. If there is enough amino acid and nutrients present, the mTORC1 will then be activated.