title: Mitochondrial DNA rearrangements associated with mF plasmid integration and plasmodial longevity in Physarum polycephalum.
abstract: 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.
authors.affiliation: Department of Molecular and Cell Biology, The University of Texas at Dallas, Richardson, TX 75080, USA.
authors.forename: C C
authors.initials: CC
authors.lastname: Nakagawa
authors.forename: E P
authors.initials: EP
authors.lastname: Jones
authors.forename: D L
authors.initials: DL
authors.lastname: Miller
mesh_terms: 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
chemical_list: D004271:DNA, Fungal; D004272:DNA, Mitochondrial