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Transposon Mediated Integration of Plasmid DNA into the Subventricular Zone of Neonatal Mice to Generate Novel Models of Glioblastoma
Published on: February 22, 2015
The Tn10 synaptic complex can capture a target DNA only after transposon excision
1Department of Molecular and Cellular Biology, Harvard University, Cambridge, Massachusetts 02138, USA.
Cell
|April 18, 1997
Summary
Tn10 transposition involves nonreplicative, post-cleavage target DNA capture. This mechanism, unlike other transposons, involves stable double-end break complexes and influences evolutionary strategies.
Area of Science:
- Molecular Biology
- Genetics
- Biochemistry
Background:
- Transposable elements (TEs) are mobile DNA sequences.
- Tn10 is a well-studied TE known for its nonreplicative transposition mechanism.
Purpose of the Study:
- To investigate the mechanism of target DNA selection in Tn10 transposition.
- To determine when Tn10 commits to a target DNA molecule during transposition.
Main Methods:
- In vitro transposition assays.
- Detection of DNA-protein complexes using biochemical methods.
- Analysis of synaptic complex formation and DNA cleavage.
Main Results:
- Tn10 synaptic complexes commit to target DNA post-double-strand cleavage, forming stable noncovalent complexes.
- Commitment does not occur with uncleaved transposon ends.
- Preincubation of cleaved complexes with target DNA accelerates strand transfer.
- Tn10's post-cleavage target capture contrasts with pre-cleavage selection by Mu and Tn7.
Conclusions:
- Tn10 exhibits a unique post-cleavage target capture mechanism.
- This strategy may promote the evolution of composite elements but could be detrimental for other transposon types.
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