A monoclonal antibody against DNA binding helix of p53 protein

Three monoclonal antibodies (Mabs) were generated against p53 DNA-binding c ore domain. When tested by immunoprecipitation, Western blot and immunofluo rescence techniques, Mab 9E4, as well as 7D3 and 6B10 reacted with both wil d-type and various mutant p53 proteins. The epitopes recognized by Mabs 7D3 , 9E4 and 6B10 were located respectively within the amino acid residues 211 -220, 281-290 and 291-300 of human p53 protein. The epitope recognized by 9 E4 Mab coincides with helix 2, also called p53 DNA binding helix, which all ows the direct contact of the protein with its target DNA sequences. This a ntibody may be useful to study transcription-dependent and transcription-in dependent activities of wild-type and mutant p53 proteins.