LAMTOR2
Function
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 (PubMed:20381137, PubMed:28935770, PubMed:29107538, PubMed:29123114, 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:28935770, PubMed:29107538, PubMed:29123114, PubMed:29158492, PubMed:30181260). Activated Ragulator and Rag GTPases function as a scaffold recruiting mTORC1 to lysosomes where it is in turn activated (PubMed:22980980, PubMed:29107538, PubMed:29123114, PubMed:29158492). Adapter protein that enhances the efficiency of the MAP kinase cascade facilitating the activation of MAPK2 (By similarity).
Involvement in disease
Immunodeficiency due to defect in MAPBP-interacting protein
ID-MAPBPIP
This form of primary immunodeficiency syndrome includes congenital neutropenia, partial albinism, short stature and B-cell and cytotoxic T-cell deficiency.
None
The disease is caused by variants affecting the gene represented in this entry.
Sequence Similarities
Belongs to the GAMAD family.
Cellular localization
- Late endosome membrane
- Peripheral membrane protein
- Cytoplasmic side
- Lysosome membrane
- Peripheral membrane protein
- Cytoplasmic side
- Recruited to lysosome and endosome membranes by LAMTOR1.
Alternative names
MAPBPIP, ROBLD3, HSPC003, LAMTOR2, Ragulator complex protein LAMTOR2, Endosomal adaptor protein p14, Late endosomal/lysosomal Mp1-interacting protein, Late endosomal/lysosomal adaptor and MAPK and MTOR activator 2, Mitogen-activated protein-binding protein-interacting protein, Roadblock domain-containing protein 3, MAPBP-interacting protein