Diffusion in inhomogeneous media: Theory and simulations applied to whole cell photobleach recovery
Diffusion in inhomogeneous media: Theory and simulations applied to whole cell photobleach recovery
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DOI：
10.1016/s0006-3495(00)76428-9
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发表时间：
2000-10-01
影响因子：
3.4
通讯作者：
Bekiranov, S
中科院分区：
文献类型：
--
作者：
Siggia, ED;Lippincott-Schwartz, J;Bekiranov, S
推导了非均匀各向同性介质中简单模型中扩散的连续介质描述，并进行了数值实现。扩散标记物的局部平均密度是从实验中输入的，以确定样本。然后，一个单独的附加参数，即有效扩散常数，允许从任何初始条件定量模拟扩散弛豫。利用这种模拟，可以模拟光漂白活细胞的大部分区域后内质网(ER)中荧光标记的蛋白质的恢复，并拟合有效扩散常数，该扩散常数是ER和标记的几何属性。这样的定量测量可以推断这个细胞器的拓扑结构和内部组织。
A continuum description for diffusion in a simple model for an inhomogeneous but isotropic media is derived and implemented numerically. The locally averaged density of diffusible marker is input from experiment to define the sample. Then a single additional parameter, the effective diffusion constant, permits the quantitative simulation of diffusive relaxation from any initial condition. Using this simulation, it is possible to model the recovery of a fluorescently tagged protein in the endoplasmic reticulum (ER) after photobleaching a substantial region of a live cell, and fit an effective diffusion constant which is a property both of the geometry of the ER and the marker. Such quantitative measurements permit inferences about the topology and internal organization of this organelle.