Characterization of the mechanical behaviour of an unusually short representative of the KIF1A family of kinesin motors

• Applicant: Professor Dr. Manfred Schliwa
• Subject Area: Biophysics
• Term: from 1999 to 2006
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 5175710

Kinesin, a common motor molecule in eukaryotic cells, derives its energy from the hydrolysis of ATP to power organelle transport. An important feature of kinesin is the ability of single molecules to advance without dissociating over distances of several micrometers along microtubules, even against forces of several piconewtons. This behavior, together with biochemical and structural observations, suggests that the two heads of kinesin interact by some hand-over-hand mechanism such that the motor progresses along the microtubule without falling off. However, the mechanism by which the heads generate forward movement, the role of the structural domains in the neck, and the nature of the interaction between the two heads remain unknown. Therefore, we propose to (1) investigate whether single-headed kinesin molecules can undergo conformational changes and generate force, (2) study the functional roles of several structural domains implicated in the hand-over-hand mechanism and (3) determine if mechanical strain coordinates the interaction between the two heads.The functional analysis of kinesin proposed in this application requires the combination of biophysical, molecular, and structural techniques which makes the collaboration of several groups indispensable. In our laboratory we intend to determine the conformational changes and forces generated by single wildtype and modified kinesins in in vitro motility assays using double laser trapping techniques. Kinesins with modified or deleted neck domains, truncated, and single-headed kinesin molecules will be created in close collaboration with Prof. Schliwa and Dr. Woehlke in their laboratory (University of Munich) and the functional consequences of these selective modifications will be analyzed. In addition, we plan to decorate microtubules with some of the kinesin motors to further characterize the functional significance of certain domains or modifications. The structural work will be carried out together with Prof. E. Mandelkow and Dr. E. M. Mandelkow (Max-Planck-Unit, Hamburg).

• DFG Programme: Priority Programmes
• Subproject of: SPP 1068: Molekulare Motoren