Peptide Inhibitors of ABL Kinases
Provided are purified compounds comprising SEQ ID NO:1, where the tyrosine at residue ( 10 ) is phosphorylated. Also provided are purified compounds comprising SEQ ID NO:1, where the amino acid sequence of the compound is less than 400 amino acids. Additionally provided are methods of determining whether an agent is a candidate inhibitor of an Abl kinase. Further provided are methods of inhibiting an Abl kinase. Also provided are methods of treating a patient having a condition characterized by a mutant Abl kinase. Additionally provided are methods of treating a patient at risk for a condition characterized by a mutant Abl kinase. Methods of labeling an Abl kinase are also provided. Additionally, methods of isolating an Abl kinase from a tissue are provided.
1 . A method of determining whether an agent is a candidate inhibitor of an Abl kinase, the method comprising
contacting a peptide consisting of an amino acid sequence at least 85% homologous to one of SEQ ID NOs:1 and 5-18 with the agent in the presence of the Abl kinase; and
determining whether the peptide is bound to the Abl kinase,
wherein if the compound is not bound to the Abl kinase, then the agent is a candidate inhibitor of the Abl kinase, and if the peptide is bound to the Abl kinase, then the agent is not a candidate inhibitor of the Abl kinase.
2 . The method of claim 1 , wherein at least one tyrosine residue of the peptide is phosphorylated.
3 . The method of claim 1 , wherein the peptide comprises an amino acid sequence that is less than 400 amino acid residues.
4 . The method of claim 3 , wherein the peptide comprises an amino acid sequence that is less than 20 amino acid residues.
5 . The method of claim 3 , wherein the peptide comprises an amino acid sequence that is 14 amino acid residues.
6 . The method of claim 1 , wherein at least one of the peptide or the Abl kinase further comprises a detectable moiety.
7 . The method of claim 6 , wherein the detectable moiety is selected from the group consisting of a radioactive moiety, an antigen, a fluorescent moiety, or a His6 moiety.
8 . The method of claim 7 , wherein the detectable fluorescence of the fluorescent moiety changes intensity when the compound is combined with an Abl kinase.
9 . The method of claim 1 , wherein the determining step comprises measuring the apparent size of the peptide or Abl kinase under non-denaturing conditions.
10 . The method of claim 1 , further comprising assessing kinase activity of the Abl kinase in the presence of a candidate inhibitor.