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bioRxiv · 10.1101/2021.07.17.452746

A reference translatome map reveals two modes of protein evolution

Wacholder, A.·Acar, O.·Carvunis, A.-R.
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Abstract

Translation is the process by which ribosomes synthesize proteins. Ribosome profiling recently revealed that many short sequences previously thought to be noncoding are pervasively translated. To identify protein-coding genes in this noncanonical translatome, we combine an integrative framework for extremely sensitive ribosome profiling analysis, iRibo, with high-powered selection inferences tailored for short sequences. We construct a reference translatome for Saccharomyces cerevisiae comprising 5,400 canonical and almost 19,000 noncanonical translated elements. Only 14 noncanonical elements were evolving under detectable purifying selection. Surprisingly, a representative subset of translated elements lacking signatures of selection demonstrated involvement in processes including DNA repair, stress response and post-transcriptional regulation. Our results suggest that most translated elements are not conserved protein-coding genes and contribute to genotype-phenotype relationships through fast-evolving molecular mechanisms.

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Wacholder, A., Acar, O., Carvunis, A.-R.. 2021-07-17. A reference translatome map reveals two modes of protein evolution. https://doi.org/10.1101/2021.07.17.452746

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