Mitochondrial DNA rearrangements associated with mF plasmid integration and plasmodial longevity in Physarum polycephalum.
Plasmodial cultures of Physarum polycephalum have defined life spans and undergo a reproducible decline (senescence) before losing the ability to be subcultured. Studies of the mtDNA of a long-lived Physarum strain, which does not undergo senescence, revealed a 7. 9-kb insertion in its mtDNA. This insertion is derived from a mitochondrial plasmid which enhances mitochondrial fusion and mtDNA recombination. Four different recombination events are required to convert the parental mtDNA to the form found in the long-lived strain. An additional recombination event, which deletes a 2.4-kb region of the insert from the long-lived strain, has been identified in the mtDNA of a normally senescing strain. These observations imply a mitochondrial involvement in the process of plasmodial senescence and implicate a region of the DNA derived from the mitochondrial plasmid as being necessary for plasmodial longevity.
Nakagawa
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Department of Molecular and Cell Biology, The University of Texas at Dallas, Richardson, TX 75080, USA.
Jones
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EP
Miller
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D000818:Animals; D001483:Base Sequence; D004271:DNA, Fungal / Q000235:genetics*; D004272:DNA, Mitochondrial / Q000235:genetics*; D015321:Gene Rearrangement / Q000235:genetics*; D008969:Molecular Sequence Data; D016839:Physarum polycephalum / Q000235:genetics* / Q000254:growth & development; D010957:Plasmids / Q000235:genetics*; D011995:Recombination, Genetic / Q000235:genetics; D015183:Restriction Mapping; D016415:Sequence Alignment; D017422:Sequence Analysis, DNA; D013997:Time Factors
D004271:DNA, Fungal; D004272:DNA, Mitochondrial