Stop codon context influences genome-wide stimulation of termination codon readthrough by aminoglycosides
Abstract
Stop codon readthrough (SCR) occurs when the ribosome miscodes at a stop codon. Such readthrough events can be therapeutically desirable when a premature termination codon (PTC) is found in a critical gene. To study SCR in vivo in a genome-wide manner, we treated mammalian cells with aminoglycosides and performed ribosome profiling. We find that in addition to stimulating readthrough of PTCs, aminoglycosides stimulate readthrough of normal termination codons (NTCs) genome-wide. Stop codon identity, the nucleotide following the stop codon, and the surrounding mRNA sequence context all influence the likelihood of SCR. In comparison to NTCs, downstream stop codons in 3'UTRs are recognized less efficiently by ribosomes, suggesting that targeting of critical stop codons for readthrough may be achievable without general disruption of translation termination. Finally, we find that G418-induced miscoding alters gene expression with substantial effects on translation of histone genes, selenoprotein genes, and S-adenosylmethionine decarboxylase (AMD1).
Data availability
Sequencing data have been deposited in GEO under accession number GSE138643.
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Stop Codon Context Influences Genome-Wide Stimulation of Termination Codon Readthrough by AminoglycosidesNCBI Gene Expression Omnibus, GSE138643.
Article and author information
Author details
Funding
Cystic Fibrosis Foundation (GREEN16G0)
- Jamie R Wangen
- Rachel Green
National Institutes of Health (T32 GM007445)
- Jamie R Wangen
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2020, Wangen & Green
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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