Abstract
A specific linear mitochondrial plasmid (mF) is genetically associated with the fusion of mitochondria in the true slime mould,Physarum polycephalum. In matings between mF+ and mF− strains, which respectively carry and do not carry the mF plasmid, mitochondrial fusion occurs in the zygote. Mitochondrial fusion induces recombination between specific sites in the mitochondrial DNA (mtDNA) and in the mF plasmid. To detect a region which is associated with the mitochondrial fusion in the mF plasmid, we isolated, by fluorescence microscopy, strains which showed defective mitochondrial fusion (Δmif −) from those which showed normal mitochondrial fusion (mif +). Analysis of the mitochondrial genomes of Δmif − strains showed only mtDNA which recombined with the mF plasmid in mitochondria. Comparison of this recombinant mtDNA in one Δmif − strain (NG 15) with that of amif + strain showed that a 2.2-kbp region, which included the integration site of the mF plasmid, was deleted in the Δmif − strain by recombination between the main mtDNA and the mF plasmid. In other strains, in addition to this deletion, a 6-kbp region which included both termini was deleted by recombination at six repeats of AAT sequences in the mF plasmid. Moreover, transcripts of the mF plasmid were not detected in NG15 by slot hybridization.
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Chan BS-S, Court DA, Vierula PJ, Bertrand H (1991) Thekalilo linear senescence-inducing plasmid ofNeurospora is an invertron and encodes DNA and RNA polymerases. Curr Genet 20:225–237
Court DA, Bertrand H (1992) Genetic organization and structural features ofmaranhar, a senescence-inducing linear mitochondrial plasmid ofNeurospora crassa. Curr Genet 22:385–397
Court DA, Griffiths AJF, Kraus SR, Russell PJ, Bertrand H (1991) A new senescence-inducing mitochondrial linear plasmid in fieldisolatedNeurospora crassa strains from India. Curr Genet 19: 129–137
Gott, JM, Visomirski LM, Hunter JL (1993) Substitutional and insertional RNA editing of the cytochrome c oxidase subunit 1 mRNA ofPhysarum polycephalum. J Biol Chem 268: 25483–25486
Hoffman HP, Avers CJ (1973) Mitochondrion of yeast: ultrastructural evidence for one giant, branched organelle per cell. Science 181:749–751
Kawano S, Kuroiwa T (1989) Transmission pattern of mitochondrial DNA during plasmodium formation inPhysarum polycephalum. J Gen Microbiol 135:1559–1566
Kawano S, Anderson RW, Nanba T, Kuroiwa T (1987) Polymorphism and uniparental inheritance of mitochondrial DNA inPhysarum polycephalum. J Gen Microbiol 133: 3175–3182
Kawano S, Takano H, Mori K, Kuroiwa T (1991 a) A mitochondrial plasmid that promotes mitochondrial fusion inPhysarum polycephalum. Protoplasma 160:167–169
Kawano S, Takano H, Mori K, Kuroiwa T (1991 b) The oldest laboratory strain ofPhysarum polycephalum. Physarum Newslett 22:70–75
Kawano S, Takano H, Imai J, Mori K, Kuroiwa T (1993) A genetic system controlling mitochondrial fusion in the slime mould,Physarum polycephalum. Genetics 133:213–224
Kirouac-Brunet J, Manson S, Pallotta D (1981) Multiple allelism at thematB locus inPhysarum polycephalum. Can J Genet Cytol 23: 9–16
Kuiper MTR, Sabourin JR, Lambowitz AM (1990) Identification of the reverse transcriptase encoded by the Mauriceville and Varkud mitochondrial plasmids ofNeurospora, J Biol Chem 12: 6936–6943
Mahendran R, Spottswood MS, Ghate A, Ling M-I, Jeng K, Miller DL (1994) Editing of the mitochondrial small subunit rRNA inPhysarum polycephalum. EMBO J 13:232–240
Meland S, Johansen S, Johansen T, Haugli K, Haugli FS (1991) Rapid disappearance of one parental mitochondrial genotype after isogamous mating in the myxomycetePhysarum polycephalum. Curr Genet 19:55–60
Miyakawa I, Aoi H, Sando N, Kuroiwa T (1984) Fluorescence microscopic studies of mitochondrial nucleoids during meiosis and sporulation in the yeast,Saccharomyces cerevisiae. J Cell Sci 66:21–38
Nishibayashi S, Kawano S, Kuroiwa T (1987) Light and electron microscopic observations of mitochondrial fusion in plasmodia-induced sporulation inPhysarum polycephalum. Cytologia 52: 599–614 Oeser B, Tudzynski P (1989) The linear mitochondrial plasmid pCIK1 of the phytophathogenic fungus Claviceps purpurea may code for a DNA polymerase and an RNA polymerase. Mol Gen Genet 217:132-140
Osafune T, Mihara S, Hase E, Ohkuro I (1972) Electron microscopic studies of the vegetative cellular life cycle ofChlamydomonas reinhardi Dangeard in synchronous culture. I. Some characteristics of changes in subcellular structures during the cell cycle, especially in the formation of giant mitochondria. Plant Cell Physiol 13:211–227
Sakai A, Yamashita H, Nemoto Y, Kawano S, Kuroiwa T (1991) Transcriptional activity of morphologically intact proplastid-nuclei (nucleoids) isolated from tobacco cultured cells. Plant Cell Physiol 32:835–843
Sando N, Miyakawa I, N Nishabayashi S, Kuroiwa T (1981) Arrangement of mitochondrial nucleoids during the life cycle ofSaccharomyces cerevisiae. J Gen Appl Microbiol 27:511–516
Schulte U, Lambowitz AM (1991) The LaBelle mitochondrial plasmid ofNeurospora intermedia encodes a novel DNA polymerase that may be derived from a reverse transcriptase. Mol Cell Biol 11:1696–1706
Stevens B (1981) In: Strathern JN, Jones EW, Broach JR (eds) The Molecular biology of yeastSaccharomyces cerevisiae, life cycle and inheritance. Cold Spring Harbor Laboratory, Cold Spring Harbor, New York, pp 471–504
Takano H, Kawano S, Suyama Y, Kuroiwa T (1990) Restriction map of the mitochondrial DNA of the true slime mould,Physarum polycephalum: linear form and long tandem duplication. Curr Genet 18:125–131
Takano H, Kawano S, Kuroiwa T (1991) Telomeric structures in a linear mitochondrial plasmid fromPhysarum polycephalum. Curr Genet 20:315–317
Takano H, Kawano S, Kuroiwa T (1992) Constitutive homologous recombination between mitochondrial DNA and a linear mitochondrial plasmid inPhysarum polycephalum. Curr Genet 22:221–227
Takano H, Kawano S, Kuroiwa T (1994 a) Complex terminal structure of a linear mitochondrial plasmid fromPhysarum polycephalum: three terminal inverted repeats and an ORF encoding DNA polymerase. Curr Genet 25:252–257
Takano H, Kawano S, Kuroiwa T (1994 b) Genetic organization of a linear mitochondrial plasmid (mF) that promotes mitochondrial fusion inPhysarum polycephalum. Curr Genet 26:506–511
Youngman PJ, Anderson RW, Holt CE (1981) Two multiallelic mating compatibility loci separately regulate zygote formation and zygote differentiation in the myxomycetePhysarum polycephalum. Genetics 97:513–530
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Takano, H., Mori, K., Kawano, S. et al. Rearrangements of mitochondrial DNA and the mitochondrial fusion-promoting plasmid (mF) are associated with defective mitochondrial fusion inPhysarum polycephalum . Curr Genet 29, 257–264 (1996). https://doi.org/10.1007/BF02221556
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DOI: https://doi.org/10.1007/BF02221556