Carrero G, Crawford E, Hendzel M J, de Vries G
Department of Mathematical and Statistical Sciences, University of Alberta, Edmonton, AB, T6G 2G1, Canada.
Bull Math Biol. 2004 Nov;66(6):1515-45. doi: 10.1016/j.bulm.2004.02.005.
Fluorescence recovery after photobleaching (FRAP) is an experimental technique used to measure the mobility of proteins within the cell nucleus. After proteins of interest are fluorescently tagged for their visualization and monitoring, a small region of the nucleus is photobleached. The experimental FRAP data are obtained by recording the recovery of the fluorescence in this region over time. In this paper, we characterize the fluorescence recovery curves for diffusing nuclear proteins undergoing binding events with an approximate spatially homogeneous structure. We analyze two mathematical models for interpreting the experimental FRAP data, namely a reaction-diffusion model and a compartmental model. Perturbation analysis leads to a clear explanation of two important limiting dynamical types of behavior exhibited by experimental recovery curves, namely, (1) a reduced diffusive recovery, and (2) a biphasic recovery characterized by a fast phase and a slow phase. We show how the two models, describing the same type of dynamics using different approaches, relate and share common ground. The results can be used to interpret experimental FRAP data in terms of protein dynamics and to simplify the task of parameter estimation. Application of the results is demonstrated for nuclear actin and type H1 histone.
光漂白后荧光恢复（FRAP）是一种用于测量细胞核内蛋白质流动性的实验技术。在将感兴趣的蛋白质进行荧光标记以便可视化和监测之后，细胞核的一个小区域被光漂白。通过记录该区域荧光随时间的恢复情况来获得实验性的FRAP数据。在本文中，我们对经历结合事件且具有近似空间均匀结构的扩散性核蛋白的荧光恢复曲线进行了表征。我们分析了两种用于解释实验性FRAP数据的数学模型，即反应扩散模型和区室模型。微扰分析对实验恢复曲线所呈现的两种重要的极限动力学行为类型给出了清晰解释，即：（1）扩散恢复降低，以及（2）以快速相和慢速相为特征的双相恢复。我们展示了这两种使用不同方法描述相同类型动力学的模型是如何关联并具有共同基础的。这些结果可用于根据蛋白质动力学来解释实验性FRAP数据，并简化参数估计任务。针对核肌动蛋白和H1组蛋白展示了结果的应用。
