Meeuse Milou Wm, Hauser Yannick P, Morales Moya Lucas J, Hendriks Gert-Jan, Eglinger Jan, Bogaarts Guy, Tsiairis Charisios, Großhans Helge
Friedrich Miescher Institute for Biomedical Research (FMI), Basel, Switzerland.
University of Basel, Basel, Switzerland.
Mol Syst Biol. 2020 Jul;16(7):e9498. doi: 10.15252/msb.20209498.
Gene expression oscillators can structure biological events temporally and spatially. Different biological functions benefit from distinct oscillator properties. Thus, finite developmental processes rely on oscillators that start and stop at specific times, a poorly understood behavior. Here, we have characterized a massive gene expression oscillator comprising > 3,700 genes in Caenorhabditis elegans larvae. We report that oscillations initiate in embryos, arrest transiently after hatching and in response to perturbation, and cease in adults. Experimental observation of the transitions between oscillatory and non-oscillatory states at high temporal resolution reveals an oscillator operating near a Saddle Node on Invariant Cycle (SNIC) bifurcation. These findings constrain the architecture and mathematical models that can represent this oscillator. They also reveal that oscillator arrests occur reproducibly in a specific phase. Since we find oscillations to be coupled to developmental processes, including molting, this characteristic of SNIC bifurcations endows the oscillator with the potential to halt larval development at defined intervals, and thereby execute a developmental checkpoint function.
基因表达振荡器能够在时间和空间上构建生物事件。不同的生物学功能受益于不同的振荡器特性。因此，有限的发育过程依赖于在特定时间启动和停止的振荡器，而这种行为目前还知之甚少。在这里，我们对秀丽隐杆线虫幼虫中一个由超过3700个基因组成的大规模基因表达振荡器进行了表征。我们报告称，振荡在胚胎中启动，孵化后以及受到扰动时会短暂停止，并在成虫中停止。在高时间分辨率下对振荡状态和非振荡状态之间的转变进行实验观察，发现了一个在不变周期鞍结（SNIC）分岔附近运行的振荡器。这些发现限制了能够表示该振荡器的架构和数学模型。它们还揭示了振荡器的停止在特定阶段可重复发生。由于我们发现振荡与包括蜕皮在内的发育过程相关联，SNIC分岔的这一特性赋予了振荡器在特定间隔停止幼虫发育的潜力，从而执行发育检查点功能。
