title: In organello replication and viral affinity of linear, extrachromosomal DNA of the ascomycete Ascobolus immersus.
abstract: Linear, extrachromosomal DNA's of the filamentous fungus Ascobolus immersus are localized within the mitochondria. These linear plasmids have no homology to the high molecular weight mtDNA (hmw mtDNA). For analysis of plasmid replication an in organello DNA synthesis system was developed, in which radionucleotides were incorporated into intact mitochondria. Plasmid DNA is labelled preferentially in this system. From replication analysis of a specific plasmid there is evidence of a virus-like protein-primed replication. Sequence analysis of this plasmid reveals that a viral DNA polymerase is encoded. Thus, these genetic elements presumably are viral remnants rather than true plasmids.
authors.affiliation: Ruhr-Universität Bochum, Lehrstuhl für Allgemeine Botanik, Federal Republic of Germany.
authors.forename: F
authors.initials: F
authors.lastname: Kempken
authors.forename: F
authors.initials: F
authors.lastname: Meinhardt
authors.forename: K
authors.initials: K
authors.lastname: Esser
mesh_terms: D000595:Amino Acid Sequence; D001203:Ascomycota / Q000235:genetics*; D001483:Base Sequence; D003062:Codon; D004261:DNA Replication; D004272:DNA, Mitochondrial / Q000302:isolation & purification; D004259:DNA-Directed DNA Polymerase / Q000378:metabolism; D005111:Extrachromosomal Inheritance; D005656:Fungal Proteins / Q000235:genetics; D008969:Molecular Sequence Data; D009693:Nucleic Acid Hybridization; D010957:Plasmids; D012150:Polymorphism, Restriction Fragment Length; D012689:Sequence Homology, Nucleic Acid; D014764:Viral Proteins / Q000235:genetics
chemical_list: D003062:Codon; D004272:DNA, Mitochondrial; D005656:Fungal Proteins; D014764:Viral Proteins; D004259:DNA-Directed DNA Polymerase