Degradation of initiator tRNA Met by Xrn1/2 via its accumulation in the nucleus of heat-treated HeLa cells
Open Access
- 6 March 2013
- journal article
- research article
- Published by Oxford University Press (OUP) in Nucleic Acids Research
- Vol. 41 (8), 4671-4685
- https://doi.org/10.1093/nar/gkt153
Abstract
Stress response mechanisms that modulate the dynamics of tRNA degradation and accumulation from the cytoplasm to the nucleus have been studied in yeast, the rat hepatoma and human cells. In the current study, we investigated tRNA degradation and accumulation in HeLa cells under various forms of stress. We found that initiator tRNA Met (tRNA(iMet)) was specifically degraded under heat stress. Two exonucleases, Xrn1 and Xrn2, are involved in the degradation of tRNA(iMet) in the cytoplasm and the nucleus, respectively. In addition to degradation, we observed accumulation of tRNA(iMet) in the nucleus. We also found that the mammalian target of rapamycin (mTOR), which regulates tRNA trafficking in yeast, is partially phosphorylated at Ser2448 in the presence of rapamycin and/or during heat stress. Our results suggest phosphorylation of mTOR may correlate with accumulation of tRNA(iMet) in heat-treated HeLa cells.Keywords
This publication has 56 references indexed in Scilit:
- Angiogenin-Induced tRNA Fragments Inhibit Translation InitiationMolecular Cell, 2011
- tRNA structural and functional changes induced by oxidative stressCellular and Molecular Life Sciences, 2011
- Cancer Cell Survival Following DNA Damage-mediated Premature Senescence Is Regulated by Mammalian Target of Rapamycin (mTOR)-dependent Inhibition of Sirtuin 1Online Journal of Public Health Informatics, 2011
- Structural and biochemical studies of the 5′→3′ exoribonuclease Xrn1Nature Structural & Molecular Biology, 2011
- Angiogenin-induced tRNA-derived Stress-induced RNAs Promote Stress-induced Stress Granule Assembly*Online Journal of Public Health Informatics, 2010
- mTOR Ser-2481 Autophosphorylation Monitors mTORC-specific Catalytic Activity and Clarifies Rapamycin Mechanism of ActionJournal of Biological Chemistry, 2010
- Innate immune and chemically triggered oxidative stress modifies translational fidelityNature, 2009
- Angiogenin cleaves tRNA and promotes stress-induced translational repressionThe Journal of cell biology, 2009
- Retrograde nuclear accumulation of cytoplasmic tRNA in rat hepatoma cells in response to amino acid deprivationProceedings of the National Academy of Sciences of the United States of America, 2007
- Nonsense-mediated messenger RNA decay is initiated by endonucleolytic cleavage in DrosophilaNature, 2004