论文标题
基因表达噪声加速了生物振荡器的演变
Gene expression noise accelerates the evolution of a biological oscillator
论文作者
论文摘要
基因表达是一个生化过程，其中随机结合和未结合事件自然会在基因动力学中产生波动和细胞对细胞变异性。这些波动通常会对适当的生物学动力学和功能产生破坏性后果（例如，生物振荡器中时间和同步的损失）。在这里，我们表明，基因表达噪声违反直觉加速了生物振荡剂的演变，因此可以赋予生物体的好处。我们使用计算机模拟在不同水平的基因表达噪声下进化了两个生物振荡器的机械模型。我们首先表明，基因表达噪声在没有噪声的情况下无法振荡的参数空间区域中诱导振荡性动力学。然后，我们证明了这些噪声引起的振荡产生了一个健身景观，该景观通过突变朝着健壮和自我维持的振荡而迅速地引导进化。这些结果表明，噪声可以通过在分叉点之外揭示神秘的动态表型来帮助动态系统发展或学习新行为。
Gene expression is a biochemical process, where stochastic binding and un-binding events naturally generate fluctuations and cell-to-cell variability in gene dynamics. These fluctuations typically have destructive consequences for proper biological dynamics and function (e.g., loss of timing and synchrony in biological oscillators). Here, we show that gene expression noise counter-intuitively accelerates the evolution of a biological oscillator and, thus, can impart a benefit to living organisms. We used computer simulations to evolve two mechanistic models of a biological oscillator at different levels of gene expression noise. We first show that gene expression noise induces oscillatory-like dynamics in regions of parameter space that cannot oscillate in the absence of noise. We then demonstrate that these noise-induced oscillations generate a fitness landscape whose gradient robustly and quickly guides evolution by mutation towards robust and self-sustaining oscillation. These results suggest that noise can help dynamical systems evolve or learn new behavior by revealing cryptic dynamic phenotypes outside the bifurcation point.
