Scaling of microtubule force-velocity curves obtained at different tubulin concentrations
Scaling of microtubule force-velocity curves obtained at different tubulin concentrations
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DOI：
10.1103/physrevlett.92.248101
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发表时间：
2004-06-18
影响因子：
8.6
通讯作者：
Dogterom, M
中科院分区：
文献类型：
--
作者：
Janson, ME;Dogterom, M
我们提出了一条描述微管平均生长速度响应机械力的衰减的曲线。当用零负载下的生长速度归一化时，在两个新的和一个先前研究的微管蛋白浓度下获得的曲线合并。这种缩放比例为与力无关的分子解离速率提供了直接证据，与布朗棘轮模型一致。此外，以高达 10 nm 的精度测量微管长度变化，揭示负载下的微管在不同生长速度之间突然切换。
We present a single curve that describes the decay in average growth velocity for microtubules in response to a mechanical force. Curves obtained at two new and one previously studied tubulin concentrations coalesce when normalized with the growth velocity at zero load. This scaling provides direct evidence for a force-independent molecular off rate, in agreement with Brownian ratchet models. In addition, microtubule length changes were measured with a precision up to 10 nm, revealing that microtubules under load abruptly switch between different growth velocities.