The Structural Basis of Fungal Kinesin Fuction

• Applicant: Privatdozent Dr. Günther Woehlke
• Subject Area: Biophysics
• Term: from 1999 to 2006
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 5175170

To date, there are three families of filament-dependent motor proteins known: myosins use actin filaments, dyneins and kinesins move along microtubules. All three classes use ATP hydrolysis as an energy source, and it is suspected that the molecular events underlying motility and force generation may be based on similar principles.The small size of kinesin makes it an advantageous model for studying motor protein function. Kinesin motility assays showed that single motor molecules are able to move stepwise and processively along microtubules. Kinetic experiments revealed that ATP turnover and microtubule binding are tightly coupled processes that keep the two heads of a dimer in alternating states. The crystal structures of the core motor and the adjacent neck domains gave important clues to the biochemical basis of the stepping process.We are using fungal conventional kinesins to study motor protein function because their unusually fast gliding velocity may help understand the mechanism of chemomechanical energy transduction. Comparison with other conventional kinesins may reveal the minimal structural requirements, and domains that influence kinetic parameters such as velocity, ATP turnover or processivity. Here, we propose structural studies on fungal kinesins in order to (1) elucidate the conformation of distinctive parts of fungal kinesins, and (2) understand the roles of the neck and hinge regions that have been found to significantly affect motor characteristics.

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