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Promoter Capture Hi-C: High-resolution, Genome-wide Profiling of Promoter Interactions
Published on: June 28, 2018
The comprehensive epigenome map of piRNA clusters
Shinpei Kawaoka1, Kahori Hara, Keisuke Shoji
1Department of Agricultural and Environmental Biology, Graduate School of Agricultural and Life Sciences, University of Tokyo, Yayoi, Tokyo, Japan. kawaokashinpei@gmail.com
Nucleic Acids Research
|December 22, 2012
Summary
PIWI-interacting RNA (piRNA) clusters are euchromatic, facilitating the capture of new genetic insertions. This euchromatic state enables the generation of piRNAs, crucial for silencing transposons in animal gonads.
Area of Science:
- Epigenetics
- RNA Biology
- Genomics
Background:
- PIWI-interacting RNA (piRNA) clusters function as defense centers against transposable elements in animal gonads.
- The genome-wide chromatin states and transcription mechanisms of piRNA clusters remain largely uncharacterized.
Purpose of the Study:
- To investigate the chromatin landscape of piRNA clusters.
- To elucidate the mechanism of piRNA precursor transcription.
Main Methods:
- Analysis of transcriptome, transcription start sites (TSSs), and chromatin landscape in the BmN4 cell line.
- Epigenomic mapping and RNA polymerase II enrichment analysis.
Main Results:
- Unique piRNA clusters exhibit a highly euchromatic (open chromatin) state.
- Transcription start sites (TSSs) transcribing piRNA precursors are enriched for RNA polymerase II.
- piRNA precursors possess 5'-cap structures and 3'-polyadenylation tails.
Conclusions:
- The open chromatin structure of piRNA clusters facilitates efficient capture of new genetic insertions.
- This mechanism is essential for generating piRNAs that provide anti-transposon defense in the germline.
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