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Updated: Jun 24, 2025
11:52
Analysis of LINE-1 Retrotransposition at the Single Nucleus Level
Published on: April 23, 2016
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LINE-1 transcription activates long-range gene expression.
Xiufeng Li1, Luyao Bie1, Yang Wang1
1Tsinghua University-Peking University Joint Center for Life Sciences, School of Life Sciences, Tsinghua University, Beijing, China.
Nature Genetics
|June 7, 2024
Summary
Long interspersed nuclear elements (LINE-1 or L1) activate distant genes. L1 elements are crucial for mammalian zygotic genome activation (ZGA), with L1 knockdown causing developmental arrest.
Area of Science:
- Genomics
- Molecular Biology
- Developmental Biology
Background:
- Long interspersed nuclear elements (LINE-1 or L1) comprise 17% of the human genome.
- The precise control and function of L1 elements in gene regulation remain largely unknown.
Purpose of the Study:
- To investigate the role of L1 transcription in regulating long-range gene expression.
- To identify genes that control L1 expression and understand L1's impact on distant genes.
Main Methods:
- Genome-wide CRISPR-Cas9 screening using an L1 5' UTR reporter in human cells.
- Analysis of physical interactions between L1 elements and distal target genes.
- L1 knockdown experiments in mouse embryos.
Main Results:
- L1 transcription was found to activate gene expression over long genomic distances.
- Knockout of regulatory genes significantly altered L1 expression and impacted distant gene expression.
- L1 elements physically interact with distal genes, with interaction strength correlating to L1 activity.
- L1 elements activate genes essential for zygotic genome activation (ZGA).
Conclusions:
- L1 elements play a critical role in activating long-range gene expression.
- L1 regulation is essential for mammalian zygotic genome activation (ZGA).
- Disruption of L1 function leads to developmental arrest in mouse embryos.
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