通过膜纳米管的非线性材料和离子传输。
Nonlinear material and ionic transport through membrane nanotubes.
机构信息
Federal Research and Clinical Center of Physical-Chemical Medicine, Moscow 119435, Russia; Department of Molecular and Biological Physics, Moscow Institute of Physics and Technology, Institutskiy lane 9, Dolgoprudnyy, Moskow region 141700, Russia.
A.N. Frumkin Institute of Physical Chemistry and Electrochemistry, Russian Academy of Sciences, Moscow 119071, Russia.
出版信息
Biochim Biophys Acta Biomembr. 2021 Oct 1;1863(10):183677. doi: 10.1016/j.bbamem.2021.183677. Epub 2021 Jun 9.
Membrane nanotubes (NTs) and their networks play an important role in intracellular membrane transport and intercellular communications. The transport characteristics of the NT lumen resemble those of conventional solid-state nanopores. However, unlike the rigid pores, the soft membrane wall of the NT can be deformed by forces driving the transport through the NT lumen. This intrinsic coupling between the NT geometry and transport properties remains poorly explored. Using synchronized fluorescence microscopy and conductance measurements, we revealed that the NT shape was changed by both electric and hydrostatic forces driving the ionic and solute fluxes through the NT lumen. Far from the shape instability, the strength of the force effect is determined by the lateral membrane tension and is scaled with membrane elasticity so that the NT can be operated as a linear elastic sensor. Near shape instabilities, the transport forces triggered large-scale shape transformations, both stochastic and periodic. The periodic oscillations were coupled to a vesicle passage along the NT axis, resembling peristaltic transport. The oscillations were parametrically controlled by the electric field, making NT a highly nonlinear nanofluidic circuitry element with biological and technological implications.
细胞膜纳米管(NTs)及其网络在细胞内膜运输和细胞间通讯中起着重要作用。NT 腔的传输特性类似于传统的固态纳米孔。然而,与刚性孔不同的是,推动 NT 腔中物质运输的力会使 NT 的软膜壁发生变形。这种 NT 几何形状和传输特性之间的固有耦合仍未得到充分探索。通过同步荧光显微镜和电导测量,我们揭示了电和静水压两种驱动力均会改变 NT 的形状,从而推动离子和溶质通过 NT 腔。在远离形状不稳定性的情况下,力的作用强度取决于横向膜张力,并与膜弹性成比例,从而使 NT 能够作为线性弹性传感器运行。在接近形状不稳定性的情况下,传输力会引发大规模的形状变化,包括随机和周期性的变化。周期性的振荡与沿着 NT 轴的囊泡通过相耦合,类似于蠕动运输。振荡可以通过电场进行参数控制,使 NT 成为具有生物学和技术意义的高度非线性纳流电路元件。