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Updated: May 10, 2026
07:34
A Method to Study de novo Formation of Chromatin Domains
Published on: August 23, 2019
Identification and Validation of a Putative Polycomb Responsive Element in the Human Genome
Hemant Bengani1, Shweta Mendiratta, Jayant Maini
1Dr. B. R. Ambedkar Centre for Biomedical Research, University of Delhi, Delhi, India.
Plos One
|June 28, 2013
Summary
Scientists identified a novel Polycomb Responsive Element (PRE-PIK3C2B) in human DNA that interacts with Polycomb group proteins (PcG) to regulate gene expression, demonstrating conserved epigenetic mechanisms.
Area of Science:
- Epigenetics
- Molecular Biology
- Genomics
Background:
- Epigenetic cellular memory relies on Polycomb and Trithorax group proteins, conserved across metazoans.
- Mammalian cis-acting elements interacting with these proteins remain poorly understood.
Purpose of the Study:
- To identify and characterize novel cis-acting elements involved in Polycomb-mediated epigenetic regulation in mammals.
- To investigate the function and mechanism of a newly identified Polycomb Responsive Element (PRE).
Main Methods:
- Reporter gene assays in HEK cells to assess regulatory function.
- In vitro binding assays and in vivo co-immunoprecipitation to study protein interactions.
- Chromatin immunoprecipitation to analyze histone modifications (H3K27me3, H3K4me3).
- Transgenic Drosophila models to evaluate PRE function in a different organism.
Main Results:
- A novel Polycomb Responsive Element, PRE-PIK3C2B, containing YY1 binding motifs was identified in the human PIK3C2B gene.
- PRE-PIK3C2B repressed reporter gene expression dependent on Polycomb group proteins (PcG).
- PRE-PIK3C2B directly bound YY1, recruited the PRC2 complex in vivo, and showed bivalent histone marks (H3K27me3/H3K4me3).
- Functional assays in Drosophila demonstrated PRE-PIK3C2B's ability to downregulate gene expression, exhibit variegation and pairing-sensitive silencing.
Conclusions:
- PRE-PIK3C2B functions as a crucial interaction site for Polycomb group proteins, mediating epigenetic gene regulation.
- The findings highlight conserved mechanisms of Polycomb-mediated epigenetic memory between mammals and Drosophila.
- This study provides new insights into the poorly understood cis-acting elements that govern Polycomb group protein function in mammals.
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