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Updated: Jul 11, 2026
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RNA Next-Generation Sequencing and a Bioinformatics Pipeline to Identify Expressed LINE-1s at the Locus-Specific Level
Published on: May 19, 2019
Context-specific regulation of LINE-1
Ivo Teneng1, Vilius Stribinskis, Kenneth S Ramos
1Department of Biochemistry and Molecular Biology, and Center for Genetics and Molecular Medicine, University of Louisville School of Medicine, Louisville, KY 40292, USA.
Genes to Cells : Devoted to Molecular & Cellular Mechanisms
|October 2, 2007
Summary
Cellular stress activates long interspersed nuclear element-1 (LINE-1) differently across cell types. The aryl hydrocarbon receptor (AHR) and oxidative stress are key factors influencing this gene activation response.
Area of Science:
- Molecular Biology
- Genomics
- Cell Biology
Background:
- Long interspersed nuclear element-1 (LINE-1 or L1) are retrotransposons that can impact genome stability.
- Cellular stress is known to influence the activity of repetitive elements like L1.
- The aryl hydrocarbon receptor (AHR) is a transcription factor involved in cellular responses to xenobiotics and stress.
Purpose of the Study:
- To investigate the contextual specificity of L1 activation by cellular stress.
- To determine the role of the AHR and oxidative stress in L1 gene activation.
Main Methods:
- Exposure of various cell lines (HeLa, HMEC, mVSMC, mK4) to different cellular stressors (benzo(a)pyrene, TCDD, UV irradiation).
- Measurement of L1 expression and transactivation of the L1Md-A5 promoter.
- Genetic and pharmacological manipulation to assess the involvement of AHR and oxidative stress.
Main Results:
- Benzo(a)pyrene (BaP) activated L1 expression and L1 promoter transactivation in all tested cell types.
- 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) and UV irradiation induced L1 only in HeLa cells.
- AHR and oxidative stress were identified as critical determinants for L1 inducibility by cellular stress.
Conclusions:
- L1 activation by cellular stress is context-dependent, varying significantly across different cell types.
- The AHR pathway and oxidative stress play crucial roles in modulating L1 responses to cellular stress.
- These findings highlight the complex interplay between environmental factors, cellular signaling, and mobile element activity.
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