Department of Physics and Astronomy, Ohio University, Athens, OH 45701, United States of America.
Phys Biol. 2020 Jun 19;17(4):046004. doi: 10.1088/1478-3975/ab907d.
Cytoplasmic dynein is an important molecular motor involved in the transport of vesicular and macromolecular cargo along microtubules in cells, often in conjunction with kinesin motors. Dynein is larger and more complex than kinesin and the mechanism and regulation of its movement is currently the subject of intense research. While it was believed for a long time that dynein motors are relatively weak in terms of the force they can generate, recent studies have shown that interactions with regulatory proteins confer large stall forces comparable to those of kinesin. This paper reports on a theoretical study which suggests that these large stall forces may be the result of an emergent, ATP-dependent, bistability resulting in a dynamic catch-bonding behavior that can cause the motor to switch between high and low load-force states.
细胞质动力蛋白是一种重要的分子马达,参与细胞内囊泡和大分子货物沿着微管的运输,通常与驱动蛋白马达一起发挥作用。动力蛋白比驱动蛋白更大、更复杂,其运动的机制和调节是当前研究的热点。虽然长期以来人们认为动力蛋白马达在产生力的能力方面相对较弱,但最近的研究表明,与调节蛋白的相互作用赋予了它们较大的停顿力,与驱动蛋白相当。本文报道了一项理论研究,该研究表明这些较大的停顿力可能是一种新兴的、依赖于 ATP 的双稳态的结果,导致了一种动态的捕获键合行为,使马达在高和低负载力状态之间切换。