title: RBP-Jkappa binds to and represses transcription of the p53 tumor suppressor gene.
abstract: The tightly regulated expression of p53 contributes to genomic stability and transcription of the p53 gene is induced prior to cells entering S-phase, possibly as a mechanism to insure a rapid p53 response in the event of DNA damage. We have previously described the cloning of an additional 1000bp of upstream p53 sequences that play a role in the regulated expression of p53, and identified that C/EBPbeta-2 participates in inducing p53 gene expression in a cell cycle regulated fashion. This report deals with the transcriptional regulator, RBP-Jkappa, an essential target of the Notch receptor signaling pathway. It binds to the p53 promoter in a cell cycle regulation fashion and also serves to repress p53 gene expression. We conclude from these findings that the coordinate expression of C/EBPbeta-2 and RBP-Jkappa may be linked to p53 transcription during G(0) and as cells move into S-phase. Because defects in the Notch signaling pathway have been implicated in carcinogenesis, aberrant RBP-Jkappa expression and deregulated regulation of the p53 tumor suppressor could be an important step in some forms of cancers.
authors.affiliation: Department of Biological Sciences, University of South Carolina, Columbia, 29208, USA.
authors.forename: Kristy
authors.initials: K
authors.lastname: Boggs
authors.forename: Brystol
authors.initials: B
authors.lastname: Henderson
authors.forename: David
authors.initials: D
authors.lastname: Reisman
mesh_terms: D000818:Animals; D022782:CCAAT-Enhancer-Binding Protein-beta / Q000378:metabolism; D019556:COS Cells; D002453:Cell Cycle; D002460:Cell Line; D002522:Chlorocebus aethiops; D015536:Down-Regulation; D006367:HeLa Cells; D006801:Humans; D051819:Immunoglobulin J Recombination Signal Sequence-Binding Protein / Q000378:metabolism*; D051379:Mice; D011401:Promoter Regions, Genetic; D012097:Repressor Proteins / Q000378:metabolism*; D016192:Resting Phase, Cell Cycle; D016196:S Phase; D041701:Swiss 3T3 Cells; D014158:Transcription, Genetic; D014162:Transfection; D016159:Tumor Suppressor Protein p53 / Q000235:genetics* / Q000378:metabolism
chemical_list: D022782:CCAAT-Enhancer-Binding Protein-beta; D051819:Immunoglobulin J Recombination Signal Sequence-Binding Protein; C497571:Rbpj protein, mouse; D012097:Repressor Proteins; D016159:Tumor Suppressor Protein p53