Novel motor proteins and methods for their use

Abstract

The invention provides isolated nucleic acid and amino acid sequences of HsKif9, antibodies to HsKif9, methods of screening for HsKif9 modulators using biologically active HsKif9, and kits for screening for HsKif9 modulators.

1 . An isolated nucleic acid sequence encoding a microtubule motor protein, wherein the motor protein has the following properties: (i) the protein's activity includes microtubule stimulated ATPase activity; and (ii) the protein has a sequence that has greater than 90% amino acid sequence identity to SEQ ID NO:2 or SEQ ID NO:4 as measured using a sequence comparison algorithm.  
     
     
         2 . An isolated nucleic acid sequence of  claim 1 , wherein the protein specifically binds to polyclonal antibodies generated against a protein comprising SEQ ID NO:2 or SEQ ID NO:4.  
     
     
         3 . An isolated nucleic acid sequence of  claim 1 , wherein the nucleic acid encodes SEQ ID NO:2 or SEQ ID NO:4.  
     
     
         4 . An isolated nucleic acid sequence of  claim 1 , wherein the nucleic acid has a nucleotide sequence of SEQ ID NO:1 or SEQ ID NO:3.  
     
     
         5 . An isolated nucleic acid sequence of  claim 1 , wherein the nucleic acid selectively hybridizes under stringent hybridization conditions to SEQ ID NO:1 or SEQ D NO:3.  
     
     
         6 . An expression vector comprising a nucleic acid encoding a microtubule motor protein, wherein the motor protein has the following properties: (i) the protein's activity includes microtubule stimulated ATPase activity; and (ii) the protein has a sequence that has greater than 90% amino acid sequence identity to SEQ ID NO:2 or SEQ ID NO:4 as measured using a sequence comparison algorithm.  
     
     
         7 . A host cell transfected with the vector of  claim 6 .  
     
     
         8 . An isolated microtubule motor protein, wherein the protein has greater than 90% amino acid sequence identity to SEQ ID NO:2 or SEQ ID NO:4 as measured using a sequence comparison algorithm.  
     
     
         9 . An isolated protein of  claim 8 , wherein the protein specifically binds to polyclonal antibodies generated against a protein comprising SEQ ID NO:2 or SEQ ID NO:4.  
     
     
         10 . An isolated protein of  claim 8 , wherein the protein is SEQ ID NO:2 or SEQ ID NO:4.  
     
     
         11 . An isolated protein of  claim 10 , wherein the protein has an amino acid sequence of SEQ ID NO:2.  
     
     
         12 . An isolated protein of  claim 10 , wherein the protein has an amino acid sequence of SEQ ID NO:4.  
     
     
         13 . A method for screening for modulators of HsKif9, the method comprising the steps of: 
 (i) providing biologically active HsKif9, wherein has the following properties: (i) activity including microtubule stimulated ATPase activity, and (ii) sequence that has greater than 90% amino acid sequence identity to SEQ ED NO:2 or SEQ ID NO:4 as measured using a sequence comparison algorithm;    (ii) contacting biologically active HsKif9 with a candidate agent in a test and control concentration; and    (iii) assaying for the level of HsKif9 activity, wherein the HsKif9 activity is selected from the group consisting of binding activity or ATPase activity, and wherein a change in activity between the test and control concentration indicates a modulator.    
     
     
         14 . A method of  claim 13 , wherein the screening occurs in a multi-well plate as part of a high-throughput screen.  
     
     
         15 . A method of  claim 13 , wherein the biologically active HsKif9 comprises an amino acid sequence of SEQ D NO:4.  
     
     
         16 . A compound that modulates HsKif9, wherein said compound is identified using the method of  claim 13 .  
     
     
         17 . An isolated nucleic acid comprising a sequence which has greater than 80% sequence identity with nucleotide SEQ ID NO:1 or SEQ ID NO:3.