FEATURES

FAMILY

DESCRIPTION

Also known as LTOR1_HUMAN, LAMTOR1, C11orf59, PDRO. Key component of the Ragulator complex, a multiprotein complex 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 (PubMed:20381137, PubMed:22980980, PubMed:29158492). Activated by amino acids through a mechanism involving the lysosomal V-ATPase, the Ragulator plays a dual role for the small GTPases Rag (RagA/RRAGA, RagB/RRAGB, RagC/RRAGC and/or RagD/RRAGD): it (1) acts as a guanine nucleotide exchange factor (GEF), activating the small GTPases Rag and (2) mediates recruitment of Rag GTPases to the lysosome membrane (PubMed:22980980, PubMed:30181260, PubMed:31001086, PubMed:32686708, PubMed:36476874, PubMed:29158492, PubMed:28935770). Activated Ragulator and Rag GTPases function as a scaffold recruiting mTORC1 to lysosomes where it is in turn activated (PubMed:20381137, PubMed:22980980, PubMed:29158492). LAMTOR1 is directly responsible for anchoring the Ragulator complex to the lysosomal membrane (PubMed:31001086, PubMed:32686708). LAMTOR1 wraps around the other subunits of the Ragulator complex to hold them in place and interacts with the Rag GTPases, thereby playing a key role in the recruitment of the mTORC1 complex to lysosomes (PubMed:29285400, PubMed:29107538, PubMed:29123114, PubMed:28935770). Also involved in the control of embryonic stem cells differentiation via non-canonical RagC/RRAGC and RagD/RRAGD activation: together with FLCN, it is necessary to recruit and activate RagC/RRAGC and RagD/RRAGD at the lysosomes, and to induce exit of embryonic stem cells from pluripotency via non-canonical, mTOR-independent TFE3 inactivation (By similarity). Also required for late endosomes/lysosomes biogenesis it may regulate both the recycling of receptors through endosomes and the MAPK signaling pathway through recruitment of some of its components to late endosomes (PubMed:20381137, PubMed:22980980). May be involved in cholesterol homeostasis regulating LDL uptake and cholesterol release from late endosomes/lysosomes (PubMed:20544018). May also play a role in RHOA activation (PubMed:19654316). Part of the Ragulator complex composed of LAMTOR1, LAMTOR2, LAMTOR3, LAMTOR4 and LAMTOR5 (PubMed:20381137, PubMed:22980980, PubMed:29285400, PubMed:29107538, PubMed:29123114, PubMed:29158492, PubMed:28935770, PubMed:31601708, PubMed:32868926, PubMed:35338845, PubMed:36103527, PubMed:36697823). LAMTOR4 and LAMTOR5 form a heterodimer that interacts, through LAMTOR1, with a LAMTOR2, LAMTOR3 heterodimer (PubMed:20381137, PubMed:22980980). Interacts with LAMTOR2 and LAMTOR3; the interaction is direct (PubMed:20381137, PubMed:22980980). The Ragulator complex interacts with both the mTORC1 complex and heterodimers constituted of the Rag GTPases RagA/RRAGA, RagB/RRAGB, RagC/RRAGC and RagD/RRAGD; regulated by amino acid availability (PubMed:20381137, PubMed:22980980, PubMed:32868926). The Ragulator complex interacts with SLC38A9; the probable amino acid sensor (PubMed:25561175, PubMed:25567906, PubMed:22980980). Component of the lysosomal folliculin complex (LFC), composed of FLCN, FNIP1 (or FNIP2), RagA/RRAGA or RagB/RRAGB GDP-bound, RagC/RRAGC or RagD/RRAGD GTP-bound, and Ragulator (PubMed:31672913, PubMed:31704029). Associates with the lysosomal V-ATPase complex; interaction promotes the guanine nucleotide exchange factor (GEF) of the Ragulator complex (PubMed:36476874). Interacts with MMP14 (PubMed:19654316). Interacts with CDKN1B; prevents the interaction of CDKN1B with RHOA leaving RHOA in a form accessible to activation by ARHGEF2 (PubMed:19654316). Interacts with PIP4P1 (PubMed:29644770).

Also known as LTOR1_HUMAN, LAMTOR1, C11orf59, PDRO. Key component of the Ragulator complex, a multiprotein complex involved in amino acid sensing and activation of mTORC1, a signaling complex pro ...

EXTERNAL LINKS

LAMTOR1

Ragulator complex protein LAMTOR1

LAMTOR1

Molecular Synopsis