2A-PL-1600 PDF
巨大分子モーター細胞質ダイニンの構造研究
Dyneins are large microtubule-based motor complexes (over 1000 kDa) that power a wide variety of cellular processes through the coordinated action of a number of subunits. The motor domain is located in the dynein heavy chain. Dynein’s domain organization has been revealed by EM and, more recently by X-ray crystallographic studies. The atomic structures show details of functional units constituting the motor domain, such as the ATP-hydrolyzing ring composed of six AAA+ modules, the long coiled-coil microtubule-binding stalk, and the force-generating rod-like linker. The structure uncovers how the linker and stalk interact with the ring unit, which should be critical for dynein’s motor activity. A crucial mechanism underlying the motile activity of cytoskeletal motor proteins is precise coupling between ATPase and track binding activities. In dynein, the stalk region separates these two activities with a long anti-parallel coiled-coil, so that it must mediate communication between them. Together with the X-ray structure of a functional dynein motor domain at 3.8 Å, we have solved the entire stalk domain including the microtubule-binding domain at higher resolution. In this presentation, I will discuss about dynein’s unique composite architecture and how to generate force and movements along microtubules.