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Updated: Jul 18, 2026
11:52
Analysis of LINE-1 Retrotransposition at the Single Nucleus Level
Published on: April 23, 2016
Cell divisions are required for L1 retrotransposition.
Xi Shi1, Andrei Seluanov, Vera Gorbunova
1University of Rochester, 213 Hutchison Hall, River Campus, Rochester, NY 14627-0211, USA.
Molecular and Cellular Biology
|December 6, 2006
Summary
LINE-1 retrotransposons are inhibited in non-dividing cells. This cell cycle regulation of LINE-1 (L1) retrotransposition may protect tissues from harmful mutations.
Area of Science:
- Genomics
- Molecular Biology
- Cell Biology
Background:
- LINE-1 (L1) retrotransposons are abundant in genomes and can cause mutations.
- Host control mechanisms for L1 retrotransposition remain largely unknown.
Purpose of the Study:
- To investigate if the cell cycle influences LINE-1 (L1) retrotransposition in human cells.
Main Methods:
- Utilized a retrotransposition assay in cultured human cells, including cancer cells and primary fibroblasts.
- Examined L1 retrotransposition rates in cells arrested at different cell cycle stages (G1, S, G2, M) and during senescence.
Main Results:
- Retrotransposition was significantly inhibited in cells arrested at all cell cycle stages.
- L1 retrotransposition was also suppressed during cellular senescence.
- Reduced L1 transcript levels were observed in arrested cells, correlating with inhibited retrotransposition.
Conclusions:
- Cell cycle arrest strongly inhibits LINE-1 (L1) retrotransposition.
- Reduced L1 transcript levels are a likely mechanism for this inhibition in non-dividing cells.
- This regulation may protect somatic tissues from L1-induced mutations.
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