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Updated: May 26, 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
L1 expression and regulation in humans and rodents
1School of Molecular Biosciences and Center for Reproductive Biology, Washington State University, Pullman, WA 99164, USA.
Frontiers in Bioscience (Elite Edition)
|December 29, 2011
Summary
Long interspersed elements type 1 (LINE-1s or L1s) impact mammalian genomes. This review compares L1 expression and regulation in humans and rodents, highlighting key differences and similarities in development.
Area of Science:
- Genomics
- Molecular Biology
- Developmental Biology
Background:
- Long interspersed elements type 1 (LINE-1s or L1s) are retrotransposons significantly impacting mammalian genomes.
- L1 transcription is primarily regulated by its 5' untranslated region (5'UTR), which exhibits substantial variation between human and rodent L1 families.
Purpose of the Study:
- To review and compare Long interspersed elements type 1 (L1) expression and regulation in human and rodent development.
- To highlight similarities and differences in L1 biology between species.
- To discuss the utility and challenges of L1 mouse models.
Main Methods:
- Comparative analysis of endogenous L1 expression patterns across human, rat, and mouse species.
- Examination of transcriptional and post-transcriptional regulatory factors including transcription factors, DNA methylation, piRNAs, RNAi, and host factors.
- Summary and contrast of findings from transgenic L1 mouse models versus endogenous L1 studies.
Main Results:
- Detailed comparison of L1 expression in cell lines, tumors, and normal somatic/germline tissues across developmental stages in humans and rodents.
- Identification of key regulatory factors influencing L1 expression at multiple levels.
- Contrasting insights from endogenous L1 studies and transgenic L1 mouse models.
Conclusions:
- L1 expression and regulation exhibit species-specific characteristics in human and rodent development.
- Understanding L1 regulation is crucial for comprehending its genomic impact.
- L1 mouse models offer valuable insights but require careful interpretation alongside endogenous studies.
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