Goz Eli, Mioduser Oriah, Diament Alon, Tuller Tamir
Department of Biomedical Engineering, Tel-Aviv University, Ramat Aviv 69978, Israel.
SynVaccine Ltd Ramat Hachayal, Tel Aviv 6971039, Israel.
DNA Res. 2017 Aug 1;24(4):333-342. doi: 10.1093/dnares/dsx005.
Deciphering the way gene expression regulatory aspects are encoded in viral genomes is a challenging mission with ramifications related to all biomedical disciplines. Here, we aimed to understand how the evolution shapes the bacteriophage lambda genes by performing a high resolution analysis of ribosomal profiling data and gene expression related synonymous/silent information encoded in bacteriophage coding regions.We demonstrated evidence of selection for distinct compositions of synonymous codons in early and late viral genes related to the adaptation of translation efficiency to different bacteriophage developmental stages. Specifically, we showed that evolution of viral coding regions is driven, among others, by selection for codons with higher decoding rates; during the initial/progressive stages of infection the decoding rates in early/late genes were found to be superior to those in late/early genes, respectively. Moreover, we argued that selection for translation efficiency could be partially explained by adaptation to Escherichia coli tRNA pool and the fact that it can change during the bacteriophage life cycle.An analysis of additional aspects related to the expression of viral genes, such as mRNA folding and more complex/longer regulatory signals in the coding regions, is also reported. The reported conclusions are likely to be relevant also to additional viruses.
解读基因表达调控方面如何编码在病毒基因组中是一项具有挑战性的任务,其影响涉及所有生物医学学科。在此,我们旨在通过对核糖体图谱数据以及噬菌体编码区域中编码的与基因表达相关的同义/沉默信息进行高分辨率分析,来了解进化如何塑造噬菌体λ基因。我们证明了在早期和晚期病毒基因中,针对同义密码子的不同组成存在选择证据,这与翻译效率适应不同噬菌体发育阶段有关。具体而言,我们表明,病毒编码区域的进化除其他因素外,还受到对具有更高解码率密码子的选择驱动;在感染的初始/进展阶段,早期/晚期基因的解码率分别高于晚期/早期基因。此外,我们认为对翻译效率的选择可以部分通过对大肠杆菌tRNA库的适应以及其在噬菌体生命周期中会发生变化这一事实来解释。本文还报道了对与病毒基因表达相关的其他方面的分析,如mRNA折叠以及编码区域中更复杂/更长的调控信号。所报道的结论可能也与其他病毒相关。