Methods of screening molecular libraries and active molecules identified thereby

Abstract

The present invention provides a peptide having 2 to 10 amino acids or a derivative thereof which is able to restore wild type function of human p53, for use in therapy; and a method of screening a library of molecules for the ability of members of that library to restore or modify the function of a target protein in an intracellular environment, which method comprises introducing the library into host cells which have a reporter system which allows the identification of those cells in which the function of the target protein has been restored or modified.

1 . A peptide having 2 to 10 amino acids, which is able to restore wild type function of human p53.  
     
     
         2 - 26 . (canceled)  
     
     
         27 . The peptide of  claim 1  having 3 to 7 amino acids.  
     
     
         28 . The peptide of  claim 1  wherein the peptide incorporates the tri-peptide sequence WCT.  
     
     
         29 . The peptide of  claim 28  wherein the peptide incorporates the pentapeptide sequence M-G/M/V-WCT.  
     
     
         30 . The peptide of  claim 1  wherein the peptide has been modified at the C and/or N terminus to include a signaling or targeting moiety.  
     
     
         31 . The peptide of  claim 30  wherein the signaling or targeting moiety is selected from the group comprising folate and the HIV Tat translocation sequence.  
     
     
         32 . A method of treating cancer comprising administering to a patient in need thereof a peptide having 2 to 10 amino acids which is able to restore wild type function of human p53.  
     
     
         33 . The method of  claim 32  wherein the peptide has 3 to 7 amino acids.  
     
     
         34 . The method of  claim 32  wherein the peptide incorporates the tri-peptide sequence WCT.  
     
     
         35 . The method of  claim 34  wherein the peptide incorporates the pentapeptide sequence M-G/M/V-WCT.  
     
     
         36 . The method of  claim 32 , wherein the peptide has been modified at the C and/or N terminus to include a signaling or targeting moiety.  
     
     
         37 . The method of  claim 36  wherein the signaling or targeting moiety is selected from the group comprising folate and the HIV Tat translocation sequence.  
     
     
         38 . A method of screening a library of molecules for the ability of members of the library to restore or modify the function of a target protein in an intra-cellular environment, the method comprising introducing the library into host cells having a reporter system that allows for the identification of those cells in which the function of the target protein has been restored or modified.  
     
     
         39 . The method of  claim 38  wherein the target protein is a nucleic acid binding protein.  
     
     
         40 . The method of  claim 39  wherein the nucleic acid binding protein is p53.  
     
     
         41 . The method of  claim 38  wherein the reporter system comprises a reporter gene which is operably linked to a sequence of nucleotides that provides a binding site for the target protein or for a protein that associates with, or is a substrate for, the target protein.  
     
     
         42 . The method of  claim 41  wherein the reporter gene is operably linked to a p21 or Bax promoter.  
     
     
         43 . The method of  claim 41  wherein the protein product of the reporter gene includes a secretion signal peptide.  
     
     
         44 . The method of  claim 41  wherein the protein product of the reporter gene includes a transmembrane domain.  
     
     
         45 . The method of  claim 41  wherein the host cells have been transfected with the reporter gene.  
     
     
         46 . The method of  claim 38  wherein the molecular library is a peptide library.  
     
     
         47 . The method of  claim 46  wherein the peptides have 2-8 amino acids.  
     
     
         48 . The method of  claim 46  wherein the library is introduced into the host cells in the form of nucleic acid constructs which encode the peptide library.  
     
     
         49 . The method of  claim 46  wherein each member of the peptide library has the sequence M-G/M/V-(X) n , wherein n is an integer from 3 to 18, M is methionine, G is glycine, V is valine and each X, which may be the same or different, is any genetically coded amino acid.  
     
     
         50 . The method of  claim 38  wherein the molecular library has at least 500 different members.  
     
     
         51 . The method of  claim 38  wherein the host cells are eukaryotic cells.  
     
     
         52 . A pharmaceutical composition comprising a compound, identified by a method according to  claim 38 , which is able to restore wild-type function to a mutant protein.  
     
     
         53 . A method of treatment, wherein the condition is selected from cancer, cystic fibrosis, sickle cell anemia, phenylketonuria, multiple carboxylase deficiency, methylpurine DNA glycosylasedeficiency (MPG), ataxia and chemotherapy resistance due to mutations in the gene coding for methylguanine-DNA methyl transferase (MGMT), comprising administering to a patient in need thereof the pharmaceutical composition of  claim 52.