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Updated: Mar 17, 2026
11:52
Analysis of LINE-1 Retrotransposition at the Single Nucleus Level
Published on: April 23, 2016
8.8K
Exogenous retroelement integration in sperm and embryos affects preimplantation development.
C Kitsou1, L Lazaros1, S Bellou2
1Laboratory of Medical Genetics and Human ReproductionMedical School, Ioannina University, Ioannina, Greece.
Reproduction (Cambridge, England)
|July 25, 2016
Summary
Spermatozoa can incorporate and transfer exogenous retroelements, leading to retrotransposition events. Uncontrolled retroelement RNA expression negatively impacts embryo development and morphology.
Area of Science:
- Reproductive Biology
- Molecular Genetics
- Genomics
Background:
- Retroelement transcripts are present in gametes and regulated by epigenetic mechanisms.
- Retrotransposition is essential for retroelement propagation but uncontrolled expression can harm cells.
Purpose of the Study:
- To investigate retrotransposition in mouse spermatozoa.
- To assess the impact of uncontrolled retroelement RNA on early embryos.
Main Methods:
- In vitro fertilization using spermatozoa preincubated with tagged human (LINE-1, HERVK-10) or mouse (VL30) retroelements.
- Detection of retrotransposition via PCR, FACS analysis, and confocal microscopy.
Main Results:
- Sperm cells incorporate exogenous retroelements, favoring retrotransposition.
- Inhibiting sperm reverse transcriptase reduced retrotransposition frequency.
- Spermatozoa transferred exogenous retroelements to oocytes during fertilization.
- Overexpression of retroelement RNA impaired embryo morphology and development.
Conclusions:
- Spermatozoa can incorporate and transfer exogenous retroelements, potentially causing new retrotransposition events.
- Exogenous retroelement transfer to oocytes can lead to genetic alterations in spermatozoa and embryos.
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