Revealing a human p53 universe.

Area of Science:

• Genomics
• Molecular Biology
• Cancer Research

Background:

• p53 transcriptional networks are understood, but in vivo DNA interactions and transcriptional effects in humans are not fully characterized.
• A comprehensive understanding of p53's genome-wide binding and its influence on gene expression across diverse biological contexts is needed.

Purpose of the Study:

• To globally characterize p53 DNA binding and its relationship with gene expression in human biological systems.
• To investigate the impact of DNA sequence variations (spacers and mismatches) on p53 binding in vivo.
• To identify core and context-specific p53 target genes and elucidate p53's functional roles.

Main Methods:

• Analysis of 41 genome-wide ChIP-seq datasets, including gene expression data from 16 studies.
• Development of a common analysis pipeline for consistent data interpretation.
• Utilized the p53 BAER hub and UCSC browser for data visualization and accessibility.

Main Results:

• Characterized a large p53 genome-wide cistrome of over 900 directly targeted genes.
• Established that DNA spacers and mismatches affect p53 binding but not significantly the likelihood of expression once bound.
• Identified a core cistrome signature and cell- or treatment-specific signatures, revealing new p53 functions.

Conclusions:

• p53 plays a broad homeostatic role in human cells, impacting a wide range of biological processes.
• The findings provide a robust platform for basic and translational research on p53.
• Understanding p53's genome-wide interactions is crucial for deciphering its multifaceted roles in health and disease.