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Promoter Capture Hi-C: High-resolution, Genome-wide Profiling of Promoter Interactions
Published on: June 28, 2018
Latent regulatory potential of human-specific repetitive elements
Michelle C Ward1, Michael D Wilson, Nuno L Barbosa-Morais
1University of Cambridge, Cancer Research UK-Cambridge Institute, Cambridge CB2 0RE, UK.
Molecular Cell
|December 19, 2012
Summary
The human genome contains many repetitive elements that are usually silenced. In mice, human chromosome 21 regulatory regions, including transposable elements, can be activated, revealing latent genomic potential.
Area of Science:
- Genomics
- Epigenetics
- Transposable Elements
Background:
- Repetitive elements constitute over half of the human genome.
- These elements are often lineage-specific and silenced by genetic and epigenetic mechanisms.
- Understanding the regulation of repetitive elements is crucial for deciphering genome function.
Purpose of the Study:
- To investigate if a heterologous regulatory environment can activate silenced human repetitive elements.
- To explore the epigenetic changes associated with the activation of human regulatory regions in a mouse model.
Main Methods:
- Utilized a transchromosomic mouse strain carrying human chromosome 21.
- Analyzed histone modifications and DNA methylation patterns in somatic and germline tissues.
- Examined the impact of activated regions on nearby gene expression.
Main Results:
- Hundreds of locations on human chromosome 21 associated with activating histone modifications in the mouse nucleus.
- Activation of these regions, enriched with primate and human-specific transposable elements, influenced nearby gene expression.
- Observed changes in DNA methylation at CpG dinucleotides correlated with the activation of these regulatory regions.
Conclusions:
- Demonstrated that a heterologous regulatory environment can unlock the latent regulatory potential of the human repetitive genome.
- Highlighted the species-specific nature of epigenetic mechanisms controlling repetitive element regulation.
- Provides insights into the evolutionary dynamics and functional significance of transposable elements.
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