Stimulation of p53-mediated Transcriptional Activation by the p53-binding Proteins, 53BP1 and 53BP2

• DOI: 10.1074/jbc.273.40.26061
• Publication Date: 2002-07-26T15:13:03Z
• Authors: Kuniyoshi Iwabuchi; Bin Li; Hillary F. Massa; Barbara J. Trask; Takayasu Date; Stanley Fields
• Keywords: Transcriptional Activation; 0301 basic medicine; Chromosomes, Human, Pair 15; Molecular Sequence Data; Intracellular Signaling Peptides and Proteins; Chromosome Mapping; Fluorescent Antibody Technique; Sequence Analysis, DNA; Phosphoproteins; Transfection; DNA-Binding Proteins; 03 medical and health sciences; Genes, ras; Suppression, Genetic; Chromosomes, Human, Pair 1; Tumor Cells, Cultured; Humans; Amino Acid Sequence; Cloning, Molecular; Tumor Suppressor Protein p53; Apoptosis Regulatory Proteins; Carrier Proteins

p53 is a tumor suppressor protein that controls cell proliferation by regulating the expression of growth control genes. In previous study, we identified two proteins, 53BP1 and 53BP2, are able to bind wild type but not mutant via DNA-binding domain p53. We isolated cDNAs expressing full-length human clone, which predicts 1972 residues can be detected in H358 lung carcinoma line. The <i>53BP1</i> <i>53BP2</i> genes were mapped chromosomes 15q15–21 1q41–42, respectively. Immunofluorescence studies showed three types staining patterns for as follows: both cytoplasmic nuclear, homogeneous nuclear dot pattern. contrast, 53BP2 localized exclusively cytoplasm, this pattern did change upon coexpression Although our study revealed simultaneously either or DNA carrying consensus binding site, enhanced p53-mediated transcriptional activation induced p53-dependent protein, suggesting these proteins might function signal transduction pathways promote activity.