Motor proteins and methods for their use

A method of identifying a candidate agent as a modulator of function of a target protein wherein said target protein has microtubule stimulated ATPase activity and an amino acid sequence SEQ ID NO:2, SEQ ID NO:4, or SEQ ID NO:6 and said method comprises:

• a) adding a candidate agent to a mixture comprising said target protein under conditions which normally allow production of ADP or phosphate by said target protein;
• b) subjecting the mixture to a reaction that uses said ADP or phosphate as a substrate under conditions which normally allow the ADP or phosphate to be utilized;
• and
• c) determining the level of activity of the reaction wherein a change in said level between the presence and absence of said candidate agent indicates that said candidate agent is a modulator of said target protein function.