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Yeast As a Chassis for Developing Functional Assays to Study Human P53
Published on: August 4, 2019
Deconstructing p53 transcriptional networks in tumor suppression
Kathryn T Bieging1, Laura D Attardi
1Department of Radiation Oncology, Stanford University School of Medicine, Stanford, CA 94305, USA.
Abstract:
p53 is a pivotal tumor suppressor that induces apoptosis, cell-cycle arrest and senescence in response to stress signals. Although p53 transcriptional activation is important for these responses, the mechanisms underlying tumor suppression have been elusive. To date, no single or compound mouse knockout of specific p53 target genes has recapitulated the dramatic tumor predisposition that characterizes p53-null mice. Recently, however, analysis of knock-in mice expressing p53 transactivation domain mutants has revealed a group of primarily novel direct p53 target genes that may mediate tumor suppression in vivo. We present here an overview of well-known p53 target genes and the tumor phenotypes of the cognate knockout mice, and address the recent identification of new p53 transcriptional targets and how they enhance our understanding of p53 transcriptional networks central for tumor suppression.
Insights
The tumor suppressor p53 protein
Area of Science:
- Molecular Biology
- Genetics
- Cancer Research
Background:
- The p53 protein is a crucial tumor suppressor involved in cellular responses to stress.
- Its role in tumor suppression is complex, with mechanisms not fully understood despite its importance.
- Existing knockout studies of known p53 target genes have not fully replicated p53-null mouse phenotypes.
Purpose of the Study:
- To review established p53 target genes and their associated tumor phenotypes.
- To discuss newly identified direct p53 target genes.
- To elucidate the role of novel p53 targets in tumor suppression.
Main Methods:
- Review of existing literature on p53 target genes and knockout mouse models.
- Analysis of data from knock-in mice expressing p53 transactivation domain mutants.
- Identification and characterization of novel direct p53 transcriptional targets.
Main Results:
- Established p53 target genes do not fully explain the tumor predisposition seen in p53-null mice.
- Novel direct p53 target genes have been identified through analysis of transactivation domain mutant mice.
- These novel targets are implicated in mediating tumor suppression in vivo.
Conclusions:
- Understanding p53's transcriptional network is key to comprehending tumor suppression.
- Newly identified p53 targets offer deeper insights into its tumor suppressor functions.
- Further research into these novel targets may reveal new therapeutic strategies for cancer.
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