Ragulator complex protein LAMTOR5 (LAMTOR5)

As part of the Ragulator complex it is involved in amino acid sensing and activation of mTORC1, a signaling complex promoting cell growth in response to growth factors, energy levels, and amino acids. Activated by amino acids via a mechanism involving the lysosomal V-ATPase, the Ragulator functions as a guanine nucleotide exchange factor triggering the little GTPases Rag.

Activated Ragulator and Rag GTPases function as a scaffold recruiting mTORC1 to lysosomes where it is subsequently activated. When complexed to BIRC5, interferes with apoptosome assembly, preventing recruitment of pro-caspase-9 to oligomerized APAF1, thereby selectively suppressing apoptosis initiated via the mitochondrial/cytochrome c pathway.