Regulator of the TOR pathway, a signaling cascade that promotes cell growth in response to growth factors, energy levels, and amino acids. As part of the Ragulator complex, recruits the Rag GTPases and the mTORC1 complex to lysosomes, a key step in activation of the TOR signaling cascade by amino acids. Adapter protein that enhances the efficiency of the MAP kinase cascade facilitating the activation of MAPK2. Interacts with MAP2K1/MEK1 and MAPK2. Interacts with MORG1. Part of the Ragulator complex composed of LAMTOR1, LAMTOR2 and LAMTOR3. Interacts with LAMTOR1; the interaction is direct. Belongs to the LAMTOR3 family. Note: This description may include information from UniProtKB.