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bioRxiv · 10.1101/2022.01.27.477990

Nascent peptide-induced translation discontinuation in eukaryotes impacts biased amino acid usage in proteomes

Ito, Y.·Chadani, Y.·Niwa, T.·Yamakawa, A.·Machida, K.·Imataka, H.·Taguchi, H.
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Abstract

Robust translation elongation of any given amino acid sequence is a prerequisite to shape proteomes. Nevertheless, nascent peptides could destabilize ribosomes, since consecutive negatively charged residues in bacterial nascent chains stochastically can induce discontinuation of translation, in a phenomenon termed intrinsic ribosome destabilization (IRD). Here, we show that IRD also occurs in eukaryotic translation. Nascent chains enriched in aspartic acid (D) or glutamic acid (E) in the N-terminal regions could prematurely terminate translation, producing premature products as peptidyl-tRNA species. Although eukaryotic ribosomes are more robust to ensure uninterrupted translation, we found many endogenous D/E-rich peptidyl-tRNAs in the N-terminal regions in cells lacking a peptidyl-tRNA hydrolase, indicating that the translation of the N-terminal D/E-rich sequences poses an inherent risk. Indeed, a bioinformatics analysis revealed that the N-terminal regions of ORFs avoid D/E enrichment, implying that the translation defect partly restricts the overall amino acid usage in proteomes.

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Ito, Y., Chadani, Y., Niwa, T., Yamakawa, A., Machida, K., Imataka, H., Taguchi, H.. 2022-01-27. Nascent peptide-induced translation discontinuation in eukaryotes impacts biased amino acid usage in proteomes. https://doi.org/10.1101/2022.01.27.477990

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