The interaction between actin and myosin V has been probed by measuring the unbinding force of individual actomyosin complexes using optical tweezers. Surprisingly, we found that in both the nucleotide-free and ADP-bound states single- and double-headed binding occurs with approximately the same probability. Estimation of the spring constant of individual actomyosin complexes confirmed that in each of the nucleotide states two distinct populations exist. These results confirm that optical nanometry can be used to reliably study the mechanism of how cytoskeleton molecular motors interact with their associated polymer lattices under solution conditions more closely resembling the intracellular environment.

中文翻译：

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负载和核苷酸状态如何影响分子运动肌球蛋白 V 的肌动蛋白丝结合模式


通过使用光镊测量单个肌动球蛋白复合物的解结合力，探究了肌动蛋白和肌球蛋白 V 之间的相互作用。令人惊讶的是，我们发现在无核苷酸和 ADP 结合状态下，单头和双头结合发生的概率大致相同。对单个肌动球蛋白复合物的弹簧常数的估计证实，在每种核苷酸状态下都存在两个不同的群体。这些结果证实，光学纳米技术可用于可靠地研究细胞骨架分子马达如何在更接近细胞内环境的溶液条件下与其相关聚合物晶格相互作用的机制。