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Glutamine and asparagine activate mTORC1 independently of Rag GTPases.

ABSTRACT: Nutrient sensing by cells is crucial, and when this sensing mechanism is disturbed, human disease can occur. mTOR complex 1 (mTORC1) senses amino acids to control cell growth, metabolism, and autophagy. Leucine, arginine, and methionine signal to mTORC1 through the well-characterized Rag GTPase signaling pathway. In contrast, glutamine activates mTORC1 through a Rag GTPase-independent mechanism that requires ADP-ribosylation factor 1 (Arf1). Here, using several biochemical and genetic approaches, we show that eight amino acids filter through the Rag GTPase pathway. Like glutamine, asparagine signals to mTORC1 through Arf1 in the absence of the Rag GTPases. Both the Rag-dependent and Rag-independent pathways required the lysosome and lysosomal function for mTORC1 activation. Our results show that mTORC1 is differentially regulated by amino acids through two distinct pathways.

SUBMITTER: Meng D

PROVIDER: S-EPMC7062167 | biostudies-literature | 2020 Mar

REPOSITORIES: biostudies-literature

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Glutamine and asparagine activate mTORC1 independently of Rag GTPases.

Meng Delong D Yang Qianmei Q Wang Huanyu H Melick Chase H CH Navlani Rishika R Frank Anderson R AR Jewell Jenna L JL

The Journal of biological chemistry 20200204 10

Nutrient sensing by cells is crucial, and when this sensing mechanism is disturbed, human disease can occur. mTOR complex 1 (mTORC1) senses amino acids to control cell growth, metabolism, and autophagy. Leucine, arginine, and methionine signal to mTORC1 through the well-characterized Rag GTPase signaling pathway. In contrast, glutamine activates mTORC1 through a Rag GTPase-independent mechanism that requires ADP-ribosylation factor 1 (Arf1). Here, using several biochemical and genetic approaches ...[more]

PMID: 32019866

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