Collective Dynamics of Cytoplasmic Dynein Motors In Vitro

Abstract

Molecular motors are necessary for fundamental biological functions such as cell division and intracellular transport. These processes, which can lead to concerted movements in the cell often rely on the interplay of a multitude of motors exerting forces on microtubules. While current insight into the mechano-chemistry of single motor proteins is quite advanced, it is not sufficient for understanding collective motor activity.Meiotic nuclear oscillations in the fission yeast Schizosaccharomyces pombe represent an easily accessible model process to study intracellular movements driven by a multitude of dynein motors [Vogel et al.]. We are developing a novel in vitro assay to identify the minimal set of components and conditions required to obtain oscillations similar to those in S. pombe. Initially we study the behavior of anti-parallel microtubule doublets [Leduc et al.] gliding on dynein. The parameters to be tested comprise motor density, ATP concentration and eventually the on- and off-rates of the motor proteins. The results of these investigations will provide insight into the collective behavior of motor proteins leading to large-scale movements in living cells.Vogel et al., PLoS Biol., 7 (2009)Leduc et al., in preparation