Deep conservation of ribosome stall sites across RNA processing genes

Abstract

The rate of translation can vary considerably depending on the mRNA template. During the elongation phase the ribosome can transiently pause or permanently stall. A pause can provide the nascent protein with the required time to fold or be transported, while stalling can serve as quality control and trigger degradation of aberrant mRNA and peptide. Ribosome profiling has allowed for the genome-wide detection of such pause and stall sites, but due to library-specific biases, these predictions are often unreliable. Here, we address this by taking advantage of the deep conservation of the protein synthesis machinery, hypothesizing that similar conservation could exist for functionally important positions of ribosome slowdown - here collectively called stall sites. We analyze multiple ribosome profiling datasets from a phylogenetically diverse group of eukaryotes: yeast, fruit fly, zebrafish, mouse, and human and identify conserved stall sites. We find thousands of stall sites across multiple species, with proline, glycine, and negatively charged amino acids being the main facilitators of stalling. Many of the sites are found in RNA processing genes, suggesting that stalling might have a conserved regulatory effect on RNA metabolism. In summary, our results provide a rich resource for the study of conserved stalling and indicate possible roles of stalling in gene regulation.