Abstract
LINE-1 retrotransposons have the potential to cause DNA damage, contribute to genome instability, and induce an interferon response. Thus, accurate measurements of their expression, especially in disease contexts where genome instability and the interferon response are relevant, are of particular importance. Illumina-based bulk RNA sequencing remains the most abundant datatype for measuring gene expression. However, “active” expression from its own internal promoter is only one source of LINE-1 aligning reads in an RNA-seq experiment. With about half a million LINE-1 sequences scattered throughout the genome, many are incorporated into other transcripts that have nothing to do with LINE-1 activity. We call this “passive” co-transcription. Here we will describe how to use L1EM, a computational method that separates active from passive LINE-1 expression at the locus-specific level.
Key words
- Transposable elements
- LINE-1
- RNA-seq
- L1
- Short reads
- Co-transcription
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McKerrow, W. (2023). Quantification of LINE-1 RNA Expression from Bulk RNA-seq Using L1EM. In: Branco, M.R., de Mendoza Soler, A. (eds) Transposable Elements. Methods in Molecular Biology, vol 2607. Humana, New York, NY. https://doi.org/10.1007/978-1-0716-2883-6_7
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DOI: https://doi.org/10.1007/978-1-0716-2883-6_7
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