Autor: |
Natalya N Pavlova, Bryan King, Rachel H Josselsohn, Sara Violante, Victoria L Macera, Santosha A Vardhana, Justin R Cross, Craig B Thompson |
Jazyk: |
angličtina |
Rok vydání: |
2020 |
Předmět: |
|
Zdroj: |
eLife, Vol 9 (2020) |
Druh dokumentu: |
article |
ISSN: |
2050-084X |
DOI: |
10.7554/eLife.62307 |
Popis: |
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. |
Databáze: |
Directory of Open Access Journals |
Externí odkaz: |
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