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Determination of S-Phase Duration Using 5-Ethynyl-2'-deoxyuridine Incorporation in Saccharomyces cerevisiae
Published on: October 21, 2022
Nuclear mitochondrial DNA activates replication in Saccharomyces cerevisiae
Laurent Chatre1, Miria Ricchetti
1Departement d'Immunologie, Institut Pasteur, Paris, France.
Plos One
|March 17, 2011
Summary
Nuclear DNA fragments of mitochondrial origin (NUMTs) can promote nuclear DNA replication. These NUMTs act as origins of replication, impacting nuclear genome stability and function.
Area of Science:
- Molecular Biology
- Genetics
- Cell Biology
Background:
- Eukaryotic nuclear genomes contain DNA fragments from mitochondria, termed NUMTs.
- The functional significance of NUMT integration into the nuclear genome remains largely unknown.
- NUMTs have been linked to human germ-line diseases, highlighting their potential impact.
Purpose of the Study:
- To investigate the functional role of NUMTs in nuclear DNA replication.
- To determine if NUMTs can act as origins of DNA replication.
- To elucidate the impact of NUMTs on nuclear genome stability.
Main Methods:
- Analysis of autonomously replicating sequence (ARS) consensus motifs within NUMTs.
- Site-directed mutagenesis of ARS motifs to assess replication activity.
- 2D-gel electrophoresis of DNA replication intermediates in yeast mutants.
- Examination of NUMT sequences adjacent to or within ARS elements.
Main Results:
- NUMTs are enriched in ARS consensus motifs crucial for DNA replication.
- Mutating ARS motifs in NUMTs significantly reduces or abolishes DNA replication activity.
- NUMTs function as late chromosomal origins of replication in yeast.
- NUMTs can act as independent replication origins or enhance existing ones.
Conclusions:
- Mitochondrial DNA sequences integrated into the nuclear genome (NUMTs) actively promote nuclear DNA replication.
- NUMTs can serve as functional origins of replication, influencing the replication dynamics of the nuclear genome.
- These findings reveal a novel role for migratory mitochondrial DNA in shaping nuclear genome replication.
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