Institute of Bioengineering (IBI), Ecole Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland.
Methods. 2022 Jul;203:10-16. doi: 10.1016/j.ymeth.2021.10.004. Epub 2021 Oct 18.
Protein synthesis is an energy consuming process characterised as a pivotal and highly regulated step in gene expression. The net protein output is dictated by a combination of translation initiation, elongation and termination rates that have remained difficult to measure. Recently, the development of ribosome profiling has enabled the inference of translation parameters through modelling, as this method informs on the ribosome position along the mRNA. Here, we present an automated, reproducible and portable computational pipeline to infer relative single-codon and codon-pair dwell times as well as gene flux from raw ribosome profiling sequencing data. As a case study, we applied our workflow to a publicly available yeast ribosome profiling dataset consisting of 57 independent gene knockouts related to RNA and tRNA modifications. We uncovered the effects of those modifications on translation elongation and codon selection during decoding. In particular, knocking out mod5 and trm7 increases codon-specific dwell times which indicates their potential tRNA targets, and highlights effects of nucleotide modifications on ribosome decoding rate.
蛋白质合成是一个耗能过程,其特征是基因表达中一个关键且高度调控的步骤。净蛋白输出由翻译起始、延伸和终止速率的组合决定,这些速率一直难以测量。最近,核糖体图谱分析的发展使通过建模推断翻译参数成为可能,因为这种方法可以了解核糖体在 mRNA 上的位置。在这里,我们提出了一种自动化、可重复和可移植的计算流程,用于从原始核糖体图谱测序数据中推断相对单密码子和密码子对停留时间以及基因通量。作为一个案例研究,我们将我们的工作流程应用于一个公开的酵母核糖体图谱数据集,该数据集由 57 个与 RNA 和 tRNA 修饰相关的独立基因敲除组成。我们揭示了这些修饰对翻译延伸和密码子选择在解码过程中的影响。特别是,敲除 mod5 和 trm7 增加了特定密码子的停留时间,这表明它们可能是 tRNA 的靶标,并突出了核苷酸修饰对核糖体解码速率的影响。