Related Experiment Video
Updated: Jul 12, 2025
11:52
Analysis of LINE-1 Retrotransposition at the Single Nucleus Level
Published on: April 23, 2016
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LINE-1 retrotransposons drive human neuronal transcriptome complexity and functional diversification.
Raquel Garza1,2, Diahann A M Atacho1,2, Anita Adami1,2
1Laboratory of Molecular Neurogenetics, Department of Experimental Medical Science, Wallenberg Neuroscience Center and Lund Stem Cell Center, BMC A11, Lund University, 221 84 Lund, Sweden.
Science Advances
|November 1, 2023
Summary
Long interspersed nuclear element-1 (L1) retrotransposons are active in the human brain, generating novel transcripts. These L1-derived RNAs contribute to human brain evolution and development.
Area of Science:
- Genetics
- Neuroscience
- Evolutionary Biology
Background:
- The genetic basis for human brain evolution, particularly its size and complexity, is not well understood.
- Long interspersed nuclear element-1 (L1) retrotransposons are known to introduce genetic diversity in primates, but their role in human physiology and brain evolution is unclear.
Purpose of the Study:
- To investigate the activity and function of L1 retrotransposons in the human brain.
- To determine the contribution of L1-derived genetic elements to human brain evolution and development.
Main Methods:
- Multiomics profiling of the human brain (developing and adult).
- Analysis of L1-derived transcripts, including chimeric and regulatory RNAs.
- CRISPR interference (CRISPRi) to silence the L1-derived long noncoding RNA LINC01876 in cerebral organoids.
Main Results:
- L1 promoters are dynamically active in both developing and adult human brains.
- Hundreds of developmentally regulated and cell type-specific L1 transcripts are generated, including chimeric transcripts and regulatory RNAs.
- The human-specific L1-derived long noncoding RNA LINC01876 is crucial for normal cerebral organoid development, with its silencing leading to reduced size and premature neural progenitor differentiation.
Conclusions:
- L1 retrotransposons contribute significantly to the complexity of the human transcriptome.
- L1-derived transcripts represent a novel layer of primate- and human-specific genetic information.
- These findings implicate L1 elements in the functional diversification and evolution of the human brain.
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