Department of Biochemistry, University of Zurich, Zurich, Switzerland.
J Evol Biol. 2011 Jun;24(6):1284-97. doi: 10.1111/j.1420-9101.2011.02261.x. Epub 2011 Mar 28.
Nongenetic perturbations, such as environmental change or developmental noise, can induce novel phenotypes. If an induced phenotype appears recurrently and confers a fitness advantage, selection may promote its genetic stabilization. Nongenetic perturbations can thus initiate evolutionary innovation. Genetic variation that is not usually phenotypically visible may play an important role in this process. Populations under stabilizing selection on a phenotype that is robust to mutations can accumulate such variation. After nongenetic perturbations, this variation can produce new phenotypes. We here study the relationship between a phenotype's mutational robustness and a population's potential to generate novel phenotypic variation. To this end, we use a well-studied model of transcriptional regulation circuits that are important in many evolutionary innovations. We find that phenotypic robustness promotes phenotypic variability in response to nongenetic perturbations, but not in response to mutation. Our work suggests that nongenetic perturbations may initiate innovation more frequently in mutationally robust gene expression traits.
非遗传干扰，如环境变化或发育噪声，可诱导新的表型。如果一个诱导的表型反复出现并赋予适应优势，选择可能会促进其遗传稳定性。因此，非遗传干扰可以引发进化创新。在这个过程中，通常表型不可见的遗传变异可能发挥重要作用。在对突变具有稳健性的表型上受到稳定选择的种群可以积累这种变异。在非遗传干扰之后，这种变异可以产生新的表型。我们在这里研究表型的突变稳健性与种群产生新的表型变异的潜力之间的关系。为此，我们使用一个经过充分研究的转录调控回路模型，该模型在许多进化创新中很重要。我们发现，表型稳健性促进了对非遗传干扰的表型可变性，但不能促进对突变的表型可变性。我们的工作表明，非遗传干扰在突变稳健的基因表达性状中可能更频繁地引发创新。
