The impact of mistranslation on phenotypic variability and fitness

Phenotypic variation is widespread in natural populations, and can significantly alter their ecology and evolution. Phenotypic variation often reflects underlying genetic variation, but also manifests via non-heritable mechanisms. For instance, translation errors result in about 10% of cellular proteins carrying altered sequences. Thus, proteome diversification arising from translation errors can potentially generate phenotypic variability, in turn increasing variability in the fate of cells or of populations. However, the link between proteome diversity and phenotypic variability remains unverified. We manipulated mistranslation levels in Escherichia coli, and measured phenotypic variability between single cells (individual level variation), as well as replicate populations (population level variation). Monitoring growth and survival, we find that mistranslation indeed increases variation across E. coli cells, but does not consistently increase variability in growth parameters across r...

表型变异（Phenotypic variation）在自然种群中广泛存在，且能显著改变其生态与进化轨迹。表型变异通常反映潜在的遗传变异（genetic variation），但也可通过非遗传机制表现。例如，翻译错误（translation errors）导致约10%的细胞蛋白质携带改变的序列。因此，由翻译错误引发的蛋白质组（proteome）多样化可能产生表型变异性，进而增加细胞或种群命运的变异性。然而，蛋白质组多样性与表型变异性之间的关联尚未得到验证。我们操纵大肠杆菌（Escherichia coli）中的错译水平，并测量单细胞间的表型变异性（个体水平变异）以及复制种群间的表型变异性（种群水平变异）。通过监测生长与存活情况，我们发现错译确实增加了大肠杆菌细胞间的变异，但并未持续提升r...的生长参数变异。