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Updated: Jul 12, 2026
11:52
Analysis of LINE-1 Retrotransposition at the Single Nucleus Level
Published on: April 23, 2016
High processivity of the reverse transcriptase from a non-long terminal repeat retrotransposon
Arkadiusz Bibillo1, Thomas H Eickbush
1Department of Biology, University of Rochester, Rochester, New York 14627-0211, USA.
The Journal of Biological Chemistry
|July 9, 2002
Summary
The R2 retrotransposable element
Area of Science:
- Molecular Biology
- Genetics
- Evolutionary Biology
Background:
- Retrotransposable elements are mobile genetic sequences.
- R2 element specifically targets 28S rRNA genes in arthropods.
- R2 encodes a protein with endonuclease and reverse transcriptase (RT) activities.
Purpose of the Study:
- Compare R2 RT activity with avian myeloblastosis virus (AMV) RT.
- Investigate processivity, elongation rates, and template displacement.
- Understand the molecular mechanisms of R2 retrotransposition.
Main Methods:
- Processivity assays with heterogeneous RNA and poly(rA) templates.
- Comparative analysis of R2 RT and AMV RT kinetics.
- RNA displacement assays during cDNA synthesis.
Main Results:
- R2 RT exhibits significantly higher processivity than AMV RT.
- R2 RT shows slower dissociation from RNA templates, contributing to higher processivity.
- R2 RT possesses RNA displacement activity, unlike AMV RT.
- Elongation rates of both enzymes are comparable.
Conclusions:
- R2 RT's enhanced processivity and RNA displacement stem from higher affinity for upstream RNA.
- These properties facilitate efficient retrotransposition into target rRNA genes.
- R2 element provides a model for studying non-retroviral RT mechanisms.
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