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Real-Time Quantification of the Effects of IS200/IS605 Family-Associated TnpB on Transposon Activity
Published on: January 20, 2023
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Dosage compensation of transposable elements in mammals
Chunyao Wei1,2, Barry Kesner1,2, Uri Weissbein1,2
1Department of Molecular Biology, Massachusetts General Hospital, Boston, MA, USA.
Biorxiv : the Preprint Server for Biology
|January 7, 2025
Summary
Transposable elements (TEs) on the X chromosome are silenced during X-chromosome inactivation (XCI) but not X-autosome balance. This study reveals TEs
Area of Science:
- Epigenetics and Genomics
- Mammalian Developmental Biology
Background:
- Mammalian dosage compensation balances X chromosome gene expression between sexes.
- X-chromosome inactivation (XCI) silences one X chromosome in females.
- Xa-hyperactivation balances X-autosome gene dosage in both sexes.
Purpose of the Study:
- To investigate the role of transposable elements (TEs) in X-chromosome dosage compensation.
- To develop bioinformatic tools for analyzing TE expression and allelic origin.
- To determine if TEs are subject to XCI or Xa-hyperactivation.
Main Methods:
- Development of a novel bioinformatic pipeline for repetitive element analysis.
- Application of the pipeline to single-embryo So-Smart-Seq data.
- Analysis of TE silencing patterns during imprinted and random XCI.
Main Results:
- X-linked transposable elements (TEs) are significantly silenced during XCI, with variations based on parental imprinting, chromosomal position, and genetic background.
- Short interspersed nuclear elements (SINEs) may influence X-chromosome 3D organization during XCI.
- TEs do not undergo Xa-hyperactivation.
Conclusions:
- Transposable elements (TEs) participate in X-chromosome inactivation (XCI) but not Xa-hyperactivation.
- TEs are subject to epigenetic regulation during dosage compensation, unlike previously assumed.
- TEs' role in XCI has evolutionary and functional implications for genome regulation.
Keywords:
ES cellImprinted X inactivationLINELTRRandom X inactivationSINEX hyperactivationXistescapeemouse preimplantation embryononcodingrepetitive elementstransposable elementsMore Related Videos
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