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, may activate the TOR signaling cascade in response to amino acids. Adapter protein that may regulate the MAP kinase cascade. Part of the Ragulator complex composed of lamtor1, lamtor2, lamtor3, lamtor4 and lamtor5. The Ragulator complex interacts with slc38a9; the probable amino acid sensor. Component of the lysosomal folliculin complex (LFC). Belongs to the LAMTOR3 family.