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Updated: May 13, 2026
11:52
Analysis of LINE-1 Retrotransposition at the Single Nucleus Level
Published on: April 23, 2016
Cell division promotes efficient retrotransposition in a stable L1 reporter cell line
Yi Xie1, Lajos Mates, Zoltán Ivics
1School of Molecular Biosciences and Center for Reproductive Biology, Washington State University, Pullman, WA, 99164, USA. wenfengan@vetmed.wsu.edu.
Mobile DNA
|March 19, 2013
Summary
Cell division significantly impacts the human genome by regulating Long interspersed element type one (L1) retrotransposition. Restricting L1 ribonucleoprotein (RNP) access to nuclear DNA during cell division may be a key regulatory mechanism.
Area of Science:
- Genomics
- Molecular Biology
- Cell Biology
Background:
- Long interspersed element type one (L1) retrotransposition actively modifies the human genome.
- L1 retrotransposition requires the formation of an L1 ribonucleoprotein (RNP) complex for nuclear entry.
- The role of cell division in regulating L1 retrotransposition is debated due to conflicting previous study results.
Purpose of the Study:
- To quantitatively investigate the effect of cell division on L1 retrotransposition.
- To clarify the role of cell cycle progression in L1 retrotransposition.
Main Methods:
- Developed a stable dual-luciferase L1 reporter cell line for quantitative monitoring.
- Utilized a bi-directional tetracycline-inducible promoter to drive L1 expression and a Renilla luciferase control.
- Arrested cells in different cell cycle stages and synchronized cells to analyze retrotransposition rates.
Main Results:
- Observed a 10-fold reduction in retrotransposition in cell-cycle arrested cells, even after normalization.
- Synchronized cells undergoing two mitoses showed 2.6-fold higher retrotransposition than those undergoing one mitosis.
- L1 expression levels were consistent between experimental groups.
Conclusions:
- Cell division plays a significant role in regulating L1 retrotransposition.
- Restricting L1 RNP access to nuclear DNA is a potential post-translational regulatory mechanism.
- Findings support cell division as a critical control point for L1 activity.
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