Codon usage biases co-evolve with transcription termination machinery to suppress premature cleavage and polyadenylation
Abstract
Codon usage biases are found in all genomes and influence protein expression levels. The codon usage effect on protein expression was thought to be mainly due to its impact on translation. Here we show that transcription termination is an important driving force for codon usage bias in eukaryotes. Using Neurospora crassa as a model organism, we demonstrated that introduction of rare codons results in premature transcription termination (PTT) within open reading frames and the abolishment of full-length mRNA. PTT is a wide-spread phenomenon in Neurospora and there is a strong negative correlation between codon usage bias and PTT events. Rare codons lead to the formation of putative poly(A) signals and PTT. A similar role for codon usage bias was also observed in mouse. Together, these results suggest that codon usage biases co-evolve with the transcription termination machinery to suppress premature termination of transcription and thus allow for optimal gene expression.
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Funding
National Institute of General Medical Sciences (R35GM118118)
- Yi Liu
Cancer Prevention and Research Institute of Texas (RP160268)
- Yi Liu
Welch Foundation (I-1560)
- Yi Liu
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2018, Zhou 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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