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Preparation of the Mgm101 Recombination Protein by MBP-based Tagging Strategy
Published on: June 25, 2013
Recombinant mitochondrial DNA molecules suggest a template switching ability for group-II-intron reverse
C H Sellem1, O Begel, A Sainsard-Chanet
1Centre de Génétique Moléculaire, Centre National de la Recherche Scientifique, Gif sur Yvette, France. Sellem@cgm.cnrs-gif.fr
Current Genetics
|February 15, 2000
Summary
Mitochondrial genome instability in Podospora anserina is linked to the mobile group-II intron COX1-i1. Its reverse transcriptase activity may cause DNA rearrangements during fungal aging and in mutants.
Area of Science:
- Molecular Biology
- Mycology
- Genetics
Background:
- Degenerative processes in Podospora anserina correlate with mitochondrial genome instability.
- The mobile group-II intron COX1-i1 (intron alpha) encodes a reverse transcriptase, contributing to this instability.
Purpose of the Study:
- To characterize mitochondrial recombinant DNA molecules formed by intron alpha.
- To investigate the role of reverse transcriptase activity in mitochondrial rearrangements.
Main Methods:
- Polymerase Chain Reaction (PCR) experiments were employed.
- Analysis of mitochondrial recombinant DNA molecules joining intron alpha 5' ends to tRNA 3' ends (including CCA motif).
Main Results:
- Characterized recombinant DNA molecules with specific junction structures.
- Proposed that RNA template switching by the intron alpha-encoded reverse transcriptase initiated these junctions.
Conclusions:
- The reverse transcriptase activity of COX1-i1 is a likely mechanism for mitochondrial rearrangements.
- This mechanism may contribute to degenerative syndromes and observed phenotypes in long-lived mutants of P. anserina.
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