Wild-type but not mutant p53 activates the hepatocyte growth factor/scatter factor promoter.
p53 transactivates the expression of a variety of genes by binding to specific DNA sequences within the promoter. We have investigated the ability of wild-type p53 and a non-DNA binding p53 mutant to activate the hepatocyte growth factor/scatter factor (HGF/SF) promoter using chloramphenicol acetyltransferase reporter constructs. We also used deletion sequences of the HGF/SF promoter to identify which regions, if any, were responsible for p53 binding. Our results show that wild-type but not mutant p53 activates the HGF/SF promoter when using -3000 and -755 bp upstream of the HGF/SF gene. This activation is lost when promoter sequences covering -365 and -239 bp are used. Analysis of the DNA sequence between -365 and -755 bp shows one putative p53 half-site with 80% homology to the consensus sequence and another half-site 3 bases downstream of this with 100% homology to the consensus sequence. In contrast to previously identified p53 binding DNA sequences, the downstream half-site is inverted. We propose that the HGF/SF promoter can be activated by wild-type p53 in vivo and that this could be as a result of a novel form of sequence-specific DNA binding.
Metcalfe
A M
AM
MRC Clinical and Biochemical Magnetic Resonance Unit, Department of Biochemistry, University of Oxford, South Parks Road, Oxford OX1 3QU, UK.
Dixon
R M
RM
Radda
G K
GK
D016475:3T3 Cells; D000818:Animals; D001665:Binding Sites; D002461:Cell Line, Transformed; D005786:Gene Expression Regulation; D017228:Hepatocyte Growth Factor / Q000235:genetics*; D006801:Humans; D051379:Mice; D009154:Mutation; D011401:Promoter Regions, Genetic; D011993:Recombinant Fusion Proteins / Q000235:genetics; D015533:Transcriptional Activation; D016159:Tumor Suppressor Protein p53 / Q000235:genetics / Q000502:physiology*
D011993:Recombinant Fusion Proteins; D016159:Tumor Suppressor Protein p53; D017228:Hepatocyte Growth Factor