Distinctive features of the biological catch bond in the jump-ramp force regime predicted by the two-pathway model.
Distinctive features of the biological catch bond in the jump-ramp force regime predicted by the two-pathway model.
复制标题
双路径模型预测的跳跃斜坡力状态中生物捕获键的显着特征。
DOI：
10.1103/physreve.72.010903
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发表时间：
2005
期刊：
影响因子：
--
通讯作者：
Sokurenko,EvgeniV
中科院分区：
文献类型：
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作者：
Pereverzev,YuriyV;Prezhdo,OlegV;Thomas,WendyE;Sokurenko,EvgeniV
在一个简单的模型，包括一个单一的结合状态和两个解结合途径的受体配体解结合的生物捕获键进行了分析。该模型详细研究了跳跃斜坡力制度，拉力迅速跳跃到一个有限的值，然后随时间线性斜坡。确定了两个定性标准，以区分捕捉债券从滑移债券。首先，断裂力概率密度的捕捉键表现出最大值-最小值对，这在有限的力量发展。相比之下，滑移粘结产生最大值，该最大值首先出现在零力处。第二，与滑动粘结相反，在较宽的斜坡率范围内，可以通过相对于最大概率的低力下的高断裂概率来识别捕获粘结，其中最大概率总是对应于最可能的断裂力。捕获债券的这两个独特的功能被掩盖了大的跳跃力，这表明捕获债券是最好的识别实验中的中等加载速率和小的跳跃力。在恒定的力制度的捕捉键的寿命有关的概率密度在跳跃斜坡制度，允许一个恒定的力，通过测量初始概率密度在跳跃斜坡实验与不同的跳跃力和固定的斜坡率，以确定键的寿命。关键的分析结果与-选择素/-选择素糖蛋白配体-1键说明。
The receptor-ligand unbinding in the biological catch bond is analyzed within a simple model that comprises a single bound state and two unbinding pathways. This model is investigated in detail for the jump-ramp force regime, where the pulling force quickly jumps to a finite value and then is ramped linearly with time. Two qualitative criteria are identified that distinguish the catch bond from the slip bond. First, the rupture force probability density of the catch-bond exhibits a maximum-minimum pair, which develops at finite forces. In contrast, the slip bond produces a maximum that first appears at zero force. Second, the catch bond can be identified over a wide range of ramp rates by high rupture probabilities at low forces relative to the probability at the maximum, in contrast to the slip bond, where the probability at the maximum always corresponds to the most likely rupture force. Both distinctive features of the catch bond are masked by large jump forces, indicating that the catch bond is best identified in experiments with moderate loading rates and small jump forces. The catch-bond lifetime in the constant force regime is related to the probability density in the jump-ramp regime, allowing one to determine the bond lifetime for a constant force by measuring the initial probability density in the jump-ramp experiments with different jump forces and a fixed ramp rate. The key analytic results are illustrated with the-selectin/-selectin glucoprotein ligand-1 bond.