Department of Cellular and Molecular Pharmacology, University of California, San Francisco, San Francisco, CA 94158, USA.
Department of Biology, University of Pennsylvania, Philadelphia, PA 19104, USA.
Cell Rep. 2016 Feb 23;14(7):1787-1799. doi: 10.1016/j.celrep.2016.01.043. Epub 2016 Feb 11.
Ribosome-footprint profiling provides genome-wide snapshots of translation, but technical challenges can confound its analysis. Here, we use improved methods to obtain ribosome-footprint profiles and mRNA abundances that more faithfully reflect gene expression in Saccharomyces cerevisiae. Our results support proposals that both the beginning of coding regions and codons matching rare tRNAs are more slowly translated. They also indicate that emergent polypeptides with as few as three basic residues within a ten-residue window tend to slow translation. With the improved mRNA measurements, the variation attributable to translational control in exponentially growing yeast was less than previously reported, and most of this variation could be predicted with a simple model that considered mRNA abundance, upstream open reading frames, cap-proximal structure and nucleotide composition, and lengths of the coding and 5' UTRs. Collectively, our results provide a framework for executing and interpreting ribosome-profiling studies and reveal key features of translational control in yeast.
核糖体足迹分析为翻译提供了全基因组快照,但技术挑战可能会使其分析变得复杂。在这里,我们使用改进的方法来获得核糖体足迹图谱和 mRNA 丰度,这些方法更能真实地反映酿酒酵母中的基因表达。我们的结果支持了以下观点,即编码区的起始和与稀有 tRNA 匹配的密码子的翻译速度更慢。它们还表明,在一个包含十个残基的窗口内,仅具有三个碱性残基的新兴多肽往往会减缓翻译。通过改进的 mRNA 测量方法,在指数生长的酵母中归因于翻译控制的变异小于先前报道的,并且可以用一个简单的模型来预测大部分变异,该模型考虑了 mRNA 丰度、上游开放阅读框、帽近端结构和核苷酸组成以及编码区和 5'UTR 的长度。总的来说,我们的结果为执行和解释核糖体分析研究提供了一个框架,并揭示了酵母中翻译控制的关键特征。