Hepatitis B X-interacting protein (HBXIP, also known as LAMTOR5) was originally recognised for its association with the X protein of hepatitis B virus (HBV) and ability to down-regulate HBV replication []. When complexed to the anti-apoptotic protein survivin, HBXIP interferes with apoptosome assembly, preventing recruitment of pro-caspase-9 to oligomerised APAF1, thereby selectively suppressing apoptosis initiated via the mitochondrial/cytochrome c pathway []. HBXIP is one of the Ragulator components that are required for mTORC1 activation by amino acids []. It is also part of the AA (amino acid) sensing machinery in human CD4+ T cells [].
This entry represents the Ragulator complex protein LAMTOR2. The Ragulator complex consists of LAMTOR1, LAMTOR2, LAMTOR3, LAMTOR4 and LAMTOR5 []. The Ragulator complex is involved in amino acid sensing and activation of the mTORC1 signalling pathway. The complex is activated by amino acids through a mechanism involving the lysosomal V-ATPase, and functions as a guanine nucleotide exchange factor activating the small GTPases Rag [], []. This entry also includes uncharacterised proteins from bacteria and archaea.
