Preliminary characterisation of chlorarachniophyte mitochondrial DNA.
The division Chlorarachniophyte comprises amoeboflagellate protists with complex chloroplasts derived from the endosymbiosis of a eukaryotic alga. Analysis of chlorarachniophyte chromosomal DNAs by pulsed-field gel electrophoresis revealed an apparently linear 36-kb chromosome that could not be ascribed to either the host or endosymbiont nuclei. A single eubacterial-like small subunit ribosomal RNA gene is encoded on this chromosome and phylogenetic analyses places this gene within a clade of mitochondrial genes from other eukaryotes. High resolution in situ hybridization demonstrates that transcripts of the small subunit ribosomal RNA gene encoded by the 36-kb chromosome are exclusively located in the mitochondria. The 36-kb chromosome thus likely represents a linear mitochondrial genome. Small amounts of an apparently dimeric (72 kb) form are also detectable in pulsed-field gel electrophoresis.
Plant Cell Biology Research Centre, School of Botany, University of Melbourne, Parkville, VIC, Australia.
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P
Gilson
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Waller
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McFadden
D000818:Animals; D001419:Bacteria / Q000145:classification / Q000235:genetics; D002736:Chloroplasts / Q000378:metabolism; D004272:DNA, Mitochondrial / Q000235:genetics* / Q000302:isolation & purification; D016054:DNA, Protozoan / Q000235:genetics* / Q000302:isolation & purification; D056890:Eukaryota / Q000145:classification / Q000235:genetics*; D005658:Fungi / Q000145:classification / Q000235:genetics; D006801:Humans; D017403:In Situ Hybridization; D007621:Karyotyping; D008928:Mitochondria / Q000378:metabolism; D010802:Phylogeny; D010944:Plants / Q000145:classification / Q000235:genetics; D014158:Transcription, Genetic
D004272:DNA, Mitochondrial; D016054:DNA, Protozoan