A spring-matrix model for pigment translocation in the red ovarian chromatophores of the freshwater shrimp Macrobrachium olfersi (Crustacea, Decapoda)
A spring-matrix model for pigment translocation in the red ovarian chromatophores of the freshwater shrimp Macrobrachium olfersi (Crustacea, Decapoda)
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DOI：
10.2307/25066668
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发表时间：
2008-04-01
影响因子：
1.6
通讯作者：
McNamara, John Campbell
中科院分区：
文献类型：
--
作者：
Boyle, Robert Tew;McNamara, John Campbell
基于作用于弹性色素基质的静息力平衡的变化，提出了一种淡水虾（Macrobrachium olfersi）红色卵巢色素细胞内色素颗粒运输的模型。该模型描述了一种色素运输机制，其中机械化学蛋白马达（如运动蛋白和肌球蛋白）交替拉伸和压缩结构统一的弹性色素基质。在颜料聚集和分散的快速阶段，弹簧基体的可量化性质服从胡克定律。色素质量的弹簧响应是由先前的红色色素浓缩激素或钙离子载体A23187诱导的色素易位动力学实验估计的。这两种易位效应都触发色素快速聚集的初始阶段，在完全聚集后，它们的去除或清除会产生色素快速分散阶段，随后是缓慢的色素易位。色素运输的快速阶段动力学与胡克定律相当一致，表明这些阶段代表了动能的释放，可能是由机械化学蛋白质马达产生的，并在转运的缓慢阶段以基质变形的形式储存。这种半定量模型应该有助于分析包含弹性成分的细胞内运输系统。
A model for intracellular transport of pigment granules in the red ovarian chromatophores of the freshwater shrimp Macrobrachium olfersi is proposed on the basis of shifts in the equilibrium of resting forces acting on an elastic pigment matrix. The model describes a pigment-transport mechanism in which mechanochemical protein motors like kinesin and myosin alternately stretch and compress a structurally unified, elastic pigment matrix. Quantifiable properties of the spring-matrix obey Hooke's Law during the rapid phases of pigment aggregation and dispersion. The spring-like response of the pigment mass is estimated from previous kinetic experiments on pigment translocation induced by red pigment concentrating hormone, or by the calcium ionophore A23187. Both translocation effectors trigger an initial phase of rapid pigment aggregation, and their removal or washout after complete aggregation produces a phase of rapid pigment dispersion, followed by slow pigment translocation. The rapid-phase kinetics of pigment transport are in reasonable agreement with Hooke's Law, suggesting that such phases represent the release of kinetic energy, probably produced by the mechanochemical protein motors and stored in the form of matrix deformation during the slow phases of translocation. This semiquantitative model should aid in analyzing intracellular transport systems that incorporate an elastic component.