A complex of LAMTOR1 to 5, known as Ragulator, interacts with Rag GTPases recruiting them to lysosomes, an essential step in mTORC1 activation (Sancak et al. 2010). LAMTOR1 is probably myristoylated and/or palmitoylated to enhance its assocation with the lysosomal surface, acting as a platform for the other members of the compex. Lamtor1 (Nada et al. 2009) and Lamtor2 (Teis et al. 2006) knockout mice exhibit severe growth retardation, severe defects in intracellular organelle organization and embryonic lethality. Partial reduction of LAMTOR2 in humans leads to reduced height (Bohn et al. 2007).