MCRS1 binds and couples Rheb to amino acid-dependent mTORC1 activation.

Ras homolog enriched in brain (Rheb) is critical for mechanistic target of rapamycin complex 1 (mTORC1) activation in response to growth factors and amino acids (AAs). Whereas growth factors inhibit the tuberous sclerosis complex (TSC1-TSC2), a negative Rheb regulator, the role of AAs in Rheb activa...

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Detalles Bibliográficos
Autores: Fawal, Mohamad-Ali, Brandt, Marta, Djouder, Nabil
Tipo de recurso: artículo
Fecha de publicación:2015
País:España
Institución:Instituto de Salud Carlos III (ISCIII)
Repositorio:Repisalud
Idioma:inglés
OAI Identifier:oai:repisalud.isciii.es:20.500.12105/17551
Acceso en línea:http://hdl.handle.net/20.500.12105/17551
Access Level:acceso abierto
Palabra clave:Adenosine Triphosphate
Amino Acids
Animals
Blotting, Western
Cells, Cultured
Colorectal Neoplasms
Endocytosis
Fibroblasts
Fluorescent Antibody Technique
Humans
Immunoenzyme Techniques
Immunoprecipitation
Integrases
Descripción
Sumario:Ras homolog enriched in brain (Rheb) is critical for mechanistic target of rapamycin complex 1 (mTORC1) activation in response to growth factors and amino acids (AAs). Whereas growth factors inhibit the tuberous sclerosis complex (TSC1-TSC2), a negative Rheb regulator, the role of AAs in Rheb activation remains unknown. Here, we identify microspherule protein 1 (MCRS1) as the essential link between Rheb and mTORC1 activation. MCRS1, in an AA-dependent manner, maintains Rheb at lysosome surfaces, connecting Rheb to mTORC1. MCRS1 suppression in human cancer cells using small interference RNA or mouse embryonic fibroblasts using an inducible-Cre/Lox system reduces mTORC1 activity. MCRS1 depletion promotes Rheb/TSC2 interaction, rendering Rheb inactive and delocalizing it from lysosomes to recycling endocytic vesicles, leading to mTORC1 inactivation. These findings have important implications for signaling mechanisms in various pathologies, including diabetes mellitus and cancer.