Arg-78 of Nprl2 catalyzes GATOR1-stimulated GTP hydrolysis by the Rag GTPases
mTOR complex 1 (mTORC1) is a major regulator of cell growth and proliferation that coordinates nutrient inputs with anabolic and catabolic processes. Amino acid signals are transmitted to mTORC1 through the Rag GTPases, which directly recruit mTORC1 onto the lysosomal surface, its site of activation...
| Main Authors: | , , , |
|---|---|
| Other Authors: | |
| Format: | Article |
| Language: | English |
| Published: |
Elsevier BV
2021
|
| Online Access: | https://hdl.handle.net/1721.1/133348 |
| _version_ | 1826196086799204352 |
|---|---|
| author | Shen, Kuang Valenstein, Max L Gu, Xin Sabatini, David M |
| author2 | Whitehead Institute for Biomedical Research |
| author_facet | Whitehead Institute for Biomedical Research Shen, Kuang Valenstein, Max L Gu, Xin Sabatini, David M |
| author_sort | Shen, Kuang |
| collection | MIT |
| description | mTOR complex 1 (mTORC1) is a major regulator of cell growth and proliferation that coordinates nutrient inputs with anabolic and catabolic processes. Amino acid signals are transmitted to mTORC1 through the Rag GTPases, which directly recruit mTORC1 onto the lysosomal surface, its site of activation. The Rag GTPase heterodimer has a unique architecture that consists of two GTPase subunits, RagA or RagB bound to RagC or RagD. Their nucleotide-loading states are strictly controlled by several lysosomal or cytosolic protein complexes that directly detect and transmit the amino acid signals. GATOR1 (GTPase-activating protein (GAP) activity toward Rags-1), a negative regulator of the cytosolic branch of the nutrient-sensing pathway, comprises three subunits, Depdc5 (DEP domain–containing protein 5), Nprl2 (NPR2-like GATOR1 complex subunit), and Nprl3 (NPR3-like GATOR1 complex subunit), and is a GAP for RagA. GATOR1 binds the Rag GTPases via two modes: an inhibitory mode that holds the Rag GTPase heterodimer and has previously been captured by structural determination, and a GAP mode that stimulates GTP hydrolysis by RagA but remains structurally elusive. Here, using site-directed mutagenesis, GTP hydrolysis assays, coimmunoprecipitation experiments, and structural analysis, we probed the GAP mode and found that a critical residue on Nprl2, Arg-78, is the arginine finger that carries out GATOR1’s GAP function. Substitutions of this arginine residue rendered mTORC1 signaling insensitive to amino acid starvation and are found frequently in cancers such as glioblastoma. Our results reveal the biochemical bases of mTORC1 inactivation through the GATOR1 complex. |
| first_indexed | 2024-09-23T10:20:38Z |
| format | Article |
| id | mit-1721.1/133348 |
| institution | Massachusetts Institute of Technology |
| language | English |
| last_indexed | 2024-09-23T10:20:38Z |
| publishDate | 2021 |
| publisher | Elsevier BV |
| record_format | dspace |
| spelling | mit-1721.1/1333482023-02-17T20:19:53Z Arg-78 of Nprl2 catalyzes GATOR1-stimulated GTP hydrolysis by the Rag GTPases Shen, Kuang Valenstein, Max L Gu, Xin Sabatini, David M Whitehead Institute for Biomedical Research Massachusetts Institute of Technology. Department of Biology Howard Hughes Medical Institute Koch Institute for Integrative Cancer Research at MIT mTOR complex 1 (mTORC1) is a major regulator of cell growth and proliferation that coordinates nutrient inputs with anabolic and catabolic processes. Amino acid signals are transmitted to mTORC1 through the Rag GTPases, which directly recruit mTORC1 onto the lysosomal surface, its site of activation. The Rag GTPase heterodimer has a unique architecture that consists of two GTPase subunits, RagA or RagB bound to RagC or RagD. Their nucleotide-loading states are strictly controlled by several lysosomal or cytosolic protein complexes that directly detect and transmit the amino acid signals. GATOR1 (GTPase-activating protein (GAP) activity toward Rags-1), a negative regulator of the cytosolic branch of the nutrient-sensing pathway, comprises three subunits, Depdc5 (DEP domain–containing protein 5), Nprl2 (NPR2-like GATOR1 complex subunit), and Nprl3 (NPR3-like GATOR1 complex subunit), and is a GAP for RagA. GATOR1 binds the Rag GTPases via two modes: an inhibitory mode that holds the Rag GTPase heterodimer and has previously been captured by structural determination, and a GAP mode that stimulates GTP hydrolysis by RagA but remains structurally elusive. Here, using site-directed mutagenesis, GTP hydrolysis assays, coimmunoprecipitation experiments, and structural analysis, we probed the GAP mode and found that a critical residue on Nprl2, Arg-78, is the arginine finger that carries out GATOR1’s GAP function. Substitutions of this arginine residue rendered mTORC1 signaling insensitive to amino acid starvation and are found frequently in cancers such as glioblastoma. Our results reveal the biochemical bases of mTORC1 inactivation through the GATOR1 complex. 2021-10-27T19:52:16Z 2021-10-27T19:52:16Z 2019 2021-07-23T17:28:36Z Article http://purl.org/eprint/type/JournalArticle https://hdl.handle.net/1721.1/133348 en 10.1074/JBC.AC119.007382 Journal of Biological Chemistry Creative Commons Attribution 4.0 International license https://creativecommons.org/licenses/by/4.0/ application/pdf Elsevier BV Journal of Biological Chemistry |
| spellingShingle | Shen, Kuang Valenstein, Max L Gu, Xin Sabatini, David M Arg-78 of Nprl2 catalyzes GATOR1-stimulated GTP hydrolysis by the Rag GTPases |
| title | Arg-78 of Nprl2 catalyzes GATOR1-stimulated GTP hydrolysis by the Rag GTPases |
| title_full | Arg-78 of Nprl2 catalyzes GATOR1-stimulated GTP hydrolysis by the Rag GTPases |
| title_fullStr | Arg-78 of Nprl2 catalyzes GATOR1-stimulated GTP hydrolysis by the Rag GTPases |
| title_full_unstemmed | Arg-78 of Nprl2 catalyzes GATOR1-stimulated GTP hydrolysis by the Rag GTPases |
| title_short | Arg-78 of Nprl2 catalyzes GATOR1-stimulated GTP hydrolysis by the Rag GTPases |
| title_sort | arg 78 of nprl2 catalyzes gator1 stimulated gtp hydrolysis by the rag gtpases |
| url | https://hdl.handle.net/1721.1/133348 |
| work_keys_str_mv | AT shenkuang arg78ofnprl2catalyzesgator1stimulatedgtphydrolysisbytheraggtpases AT valensteinmaxl arg78ofnprl2catalyzesgator1stimulatedgtphydrolysisbytheraggtpases AT guxin arg78ofnprl2catalyzesgator1stimulatedgtphydrolysisbytheraggtpases AT sabatinidavidm arg78ofnprl2catalyzesgator1stimulatedgtphydrolysisbytheraggtpases |