An image-based model of calcium waves in differentiated neuroblastoma cells
An image-based model of calcium waves in differentiated neuroblastoma cells
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DOI：
10.1016/s0006-3495(00)76281-3
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发表时间：
2000-07-01
影响因子：
3.4
通讯作者：
Loew, LM
中科院分区：
文献类型：
--
作者：
Fink, CC;Slepchenko, B;Loew, LM
在N1 E-115神经母细胞瘤细胞中，缓激肽诱导的三磷酸肌醇（InsP（3））介导的内质网（ER）释放产生的钙波已被成像。这一过程的模型是使用“虚拟细胞”建立的，虚拟细胞是一种通用的计算系统，用于整合实验图像、生物化学和电生理数据。模型的几何形状是基于一个细胞的钙波已被实验记录。相关细胞组分[InsP（3）受体（InsP（3）R）]、肌浆/内质网钙ATP酶（SERCA）泵、缓激肽受体和ER的分布基于3D共聚焦免疫荧光图像。在可能的情况下，使用已知的生物化学和电生理数据来约束模型。该模拟与实验钙波的空间和时间特征密切匹配。对InsP（3）释放后或不同细胞几何形状的钙信号的不同模式的预测得到了实验证实，从而有助于验证模型。关键成分的空间分布发生改变的模型表明，在轴突中心的波的起始来自于体细胞偏向的ER分布和InsP（3）产生偏向轴突的相互作用。模拟表明，移动的缓冲器（如指示器Fura-2）显着延迟启动和降低波的振幅。对钙扩散所起作用的分析表明，波的速度仅轻微依赖于钙扩散到邻近InsP（3）受体位点并激活其的能力。
Calcium waves produced by bradykinin-induced inositol-1,4,5-trisphosphate (InsP(3))-mediated release from endoplasmic reticulum (ER) have been imaged in N1E-115 neuroblastoma cells. A model of this process was built using the "virtual cell," a general computational system for integrating experimental image, biochemical, and electrophysiological data. The model geometry was based on a cell for which the calcium wave had been experimentally recorded. The distributions of the relevant cellular components [InsP(3) receptor (InsP(3)R)], sarcoplasmic/endoplasmic reticulum calcium ATPase (SERCA) pumps, bradykinin receptors, and ER were based on 3D confocal immunofluorescence images. Wherever possible, known biochemical and electrophysiological data were used to constrain the model. The simulation closely matched the spatial and temporal characteristics of the experimental calcium wave. Predictions on different patterns of calcium signals after InsP(3) uncaging or for different cell geometries were confirmed experimentally, thus helping to validate the model. Models in which the spatial distributions of key components are altered suggest that initiation of the wave in the center of the neurite derives from an interplay of soma-biased ER distribution and InsP(3) generation biased toward the neurite. Simulations demonstrate that mobile buffers (like the indicator fura-2) significantly delay initiation and lower the amplitude of the wave. Analysis of the role played by calcium diffusion indicated that the speed of the wave is only slightly dependent on the ability of calcium to diffuse to and activate neighboring InsP(3) receptor sites.