Investigation of Multiple-Dynein Transport of Melanosomes by Non-Invasive Force Measurement using the Fluctuation Theorem
Investigation of Multiple-Dynein Transport of Melanosomes by Non-Invasive Force Measurement using the Fluctuation Theorem
复制标题
DOI：
10.1016/j.bpj.2018.11.2216
复制
发表时间：
2018-08
影响因子：
3.4
通讯作者：
Shin Hasegawa;T. Sagawa;Kazuho Ikeda;Y. Okada;Kumiko Hayashi
中科院分区：
文献类型：
--
作者：
Shin Hasegawa;T. Sagawa;Kazuho Ikeda;Y. Okada;Kumiko Hayashi
被称为黑素体的色素细胞器在激素的作用下分散或聚集在黑素团中。这些运动是由微管马达动力蛋白-2和细胞质动力蛋白介导的。然而，与动力蛋白不同的是，动力蛋白的力产生机制尚不清楚。在本研究中，为了解决这一问题，我们研究了斑马鱼黑色素细胞中动力蛋白介导的黑素体聚集。我们应用非平衡统计力学的涨落定理来估计动力蛋白在运输过程中作用在黑素体上的力，假设系统的能量与其涨落有关。我们的研究结果表明，多个产力单位合作运输单个黑素体。由于这种力量是由动力蛋白产生的，这表明多个动力蛋白携带一个单一的黑素体。其他细胞器也有协同运输的报道；因此，多运动运输可能是细胞内移动细胞器的普遍机制。
Pigment organelles known as melanosomes disperse or aggregate in a melanophore in response to hormones. These movements are mediated by the microtubule motors kinesin-2 and cytoplasmic dynein. However, the force generation mechanism of dynein, unlike that of kinesin, is not well understood. In this study, to address this issue, we investigated the dynein-mediated aggregation of melanosomes in zebrafish melanophores. We applied the fluctuation theorem of non-equilibrium statistical mechanics to estimate forces acting on melanosomes during transport by dynein, given that the energy of a system is related to its fluctuation. Our results demonstrate that multiple force-producing units cooperatively transport a single melanosome. Since the force is generated by dynein, this suggests that multiple dyneins carry a single melanosome. Cooperative transport has been reported for other organelles; thus, multiple-motor transport may be a universal mechanism for moving organelles within the cell.