Analysis of p53-RNA interactions in cultured human cells.
Tumor suppressor p53 is a well-characterized transcription factor that binds DNA. More enigmatic are the RNA-binding properties of p53 and their physiological relevance. We used three sensitive co-immunoprecipitation methods in an attempt to detect RNAs that tightly associate with p53 in cultured human cells. Although recombinant p53 protein binds RNA in a sequence-nonspecific mode, we do not detect specific in vivo RNA binding by p53. These results suggest that RNA binding is prevented by post-translational p53 modifications. A ribonucleoprotein (not p53) is purified by multiple IgG monoclonal antibodies (including anti-p53 antibodies) from both p53 +/+ and p53 null cells. Caution is therefore required in interpreting RNA co-immunoprecipitation experiments. Though not formally excluded, these results do not support models in which p53 binds specific RNA partners in vivo.
Riley
Kasandra J-L
KJ
Department of Biochemistry and Molecular Biology, Mayo Clinic College of Medicine, Rochester, MN 55905, USA.
James Maher
L
L
D001665:Binding Sites; D001943:Breast Neoplasms; D045744:Cell Line, Tumor; D006801:Humans; D011485:Protein Binding; D012313:RNA / Q000378:metabolism*; D016601:RNA-Binding Proteins / Q000378:metabolism*; D016159:Tumor Suppressor Protein p53 / Q000378:metabolism*
D016601:RNA-Binding Proteins; D016159:Tumor Suppressor Protein p53; D012313:RNA