Functionally distinct polymorphic sequences in the human genome that are targets for p53 transactivation.
The p53 tumor suppressor protein is a master regulatory transcription factor that coordinates cellular responses to DNA damage and cellular stress. Besides mutations in p53, or in proteins involved in the p53 response pathway, genetic variation in promoter response elements (REs) of p53 target genes is expected to alter biological responses to stress. To identify SNPs in p53 REs that may modify p53-controlled gene expression, we developed an approach that combines a custom bioinformatics search to identify candidate SNPs with functional yeast and mammalian cell assays to assess their effect on p53 transactivation. Among approximately 2 million human SNPs, we identified >200 that seem to disrupt functional p53 REs. Eight of these SNPs were evaluated in functional assays to determine both the activity of the putative RE and the impact of the candidate SNPs on transactivation. All eight candidate REs were functional, and in every case the SNP pair exhibited differential transactivation capacities. Additionally, six of the eight genes adjacent to these SNPs are induced by genotoxic stress or are activated directly by transfection with p53 cDNA. Thus, this strategy efficiently identifies SNPs that may differentially affect gene expression responses in the p53 regulatory pathway.
Tomso
Daniel J
DJ
Laboratory of Molecular Genetics, National Institute of Environmental Health Sciences, National Institutes of Health, Department of Health and Human Services, Research Triangle Park, NC 27709, USA.
Inga
Alberto
A
Menendez
Daniel
D
Pittman
Gary S
GS
Campbell
Michelle R
MR
Storici
Francesca
F
Bell
Douglas A
DA
Resnick
Michael A
MA
D001483:Base Sequence; D045744:Cell Line, Tumor; D019295:Computational Biology; D018076:DNA, Complementary / Q000235:genetics; D005786:Gene Expression Regulation; D015894:Genome, Human; D006801:Humans; D008156:Luciferases; D016297:Mutagenesis, Site-Directed; D010957:Plasmids / Q000235:genetics; D020641:Polymorphism, Single Nucleotide / Q000235:genetics; D011401:Promoter Regions, Genetic / Q000235:genetics; D020218:Response Elements / Q000235:genetics; D020133:Reverse Transcriptase Polymerase Chain Reaction; D016415:Sequence Alignment; D015533:Transcriptional Activation / Q000235:genetics*; D014162:Transfection; D016159:Tumor Suppressor Protein p53 / Q000235:genetics / Q000378:metabolism*; D015003:Yeasts
D018076:DNA, Complementary; D016159:Tumor Suppressor Protein p53; D008156:Luciferases