Translation in amino acid-poor environments is limited by tRNAGln charging

  1. Natalya N Pavlova
  2. Bryan King
  3. Rachel H Josselsohn
  4. Sara Violante
  5. Victoria L Macera
  6. Santosha A Vardhana
  7. Justin R Cross
  8. Craig B Thompson  Is a corresponding author
  1. Memorial Sloan Kettering Cancer Center, United States
  2. Memorial Sloan Kettering Cance Center, United States
  3. Memorial Sloan-Kettering Cancer Center, United States

Abstract

An inadequate supply of amino acids leads to accumulation of uncharged tRNAs, which can bind and activate GCN2 kinase to reduce translation. Here, we show that glutamine-specific tRNAs selectively become uncharged when extracellular amino acid availability is compromised. In contrast, all other tRNAs retain charging of their cognate amino acids in a manner that is dependent upon intact lysosomal function. In addition to GCN2 activation and reduced total translation, the reduced charging of tRNAGln in amino acid-deprived cells also leads to specific depletion of proteins containing polyglutamine tracts including core binding factor α1, mediator subunit 12, transcriptional coactivator CBP and TATA-box binding protein. Treating amino acid-deprived cells with exogenous glutamine or glutaminase inhibitors restores tRNAGln charging and the levels of polyglutamine-containing proteins. Together, these results demonstrate that the activation of GCN2 and the translation of polyglutamine-encoding transcripts serve as key sensors of glutamine availability in mammalian cells.

Data availability

High-throughput sequencing data have been deposited in GEO (accession code GSE157276).

The following data sets were generated

Article and author information

Author details

  1. Natalya N Pavlova

    Cancer Biology and Genetics, Memorial Sloan Kettering Cancer Center, New York, United States
    Competing interests
    No competing interests declared.
  2. Bryan King

    Cancer Biology and Genetics, Memorial Sloan Kettering Cance Center, New York, United States
    Competing interests
    No competing interests declared.
  3. Rachel H Josselsohn

    Cancer Biology and Genetics, Memorial Sloan Kettering Cancer Center, New York, United States
    Competing interests
    No competing interests declared.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-6123-7744
  4. Sara Violante

    The Donald B. and Catherine C. Marron Cancer Metabolism Center, Memorial Sloan Kettering Cancer Center, New York, United States
    Competing interests
    No competing interests declared.
  5. Victoria L Macera

    Cancer Biology and Genetics, Memorial Sloan Kettering Cancer Center, New York, United States
    Competing interests
    No competing interests declared.
  6. Santosha A Vardhana

    Human Oncology and Pathogenesis Program, Memorial Sloan Kettering Cancer Center, New York, United States
    Competing interests
    No competing interests declared.
  7. Justin R Cross

    Cancer Biology and Genetics Program, Memorial Sloan-Kettering Cancer Center, New York, United States
    Competing interests
    No competing interests declared.
  8. Craig B Thompson

    Cancer Biology and Genetics Program, Memorial Sloan Kettering Cancer Center, New York, United States
    For correspondence
    thompsonc@mskcc.org
    Competing interests
    Craig B Thompson, C.B.T. is a founder of Agios Pharmaceuticals and a member of its scientific advisory board. He is also a former member of the Board of Directors and stockholder of Merck and Charles River Laboratories. He is a named inventor on patents related to cellular metabolism (see https://tinyurl.com/y35qvajq)..
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-3580-2751

Funding

National Cancer Institute (P30 CA 008748)

  • Craig B Thompson

Damon Runyon Cancer Research Foundation (DRG 2234-15)

  • Bryan King

The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.

Ethics

Animal experimentation: All animal experiments were conducted in accordance with policies and practices approved by the Memorial Sloan Kettering Cancer Center Institutional Animal Care and Use Committee (IACUC), and were carried out following the NIH guidelines for animal welfare (animal protocol #11-03-007). Every effort was made to minimize suffering.

Reviewing Editor

  1. Alan G Hinnebusch, Eunice Kennedy Shriver National Institute of Child Health and Human Development, United States

Version history

  1. Received: August 20, 2020
  2. Accepted: December 7, 2020
  3. Accepted Manuscript published: December 8, 2020 (version 1)
  4. Version of Record published: December 16, 2020 (version 2)

Copyright

© 2020, Pavlova et al.

This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.

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  1. Natalya N Pavlova
  2. Bryan King
  3. Rachel H Josselsohn
  4. Sara Violante
  5. Victoria L Macera
  6. Santosha A Vardhana
  7. Justin R Cross
  8. Craig B Thompson
(2020)
Translation in amino acid-poor environments is limited by tRNAGln charging
eLife 9:e62307.
https://doi.org/10.7554/eLife.62307

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