A novel family of mitochondrial plasmids associated with longevity mutants of Podospora anserina

• Published in: The Journal of biological chemistry Vol. 262; no. 5; pp. 2250 - 2255
• Main Authors: Turker, M.S., Domenico, J.M., Cummings, D.J.
• Format: Journal Article
• Language: English
• Published: Bethesda, MD Elsevier Inc 15-02-1987; American Society for Biochemistry and Molecular Biology
• Subjects: Ascomycota - genetics; Biological and medical sciences; CHAMPIGNON; DNA Restriction Enzymes - metabolism; DNA, Mitochondrial - analysis; Fundamental and applied biological sciences. Psychology; FUNGI; Gene Amplification; Genes. Genome; LONGEVIDAD; LONGEVITE; LONGEVITY; MITOCHONDRIA; MITOCHONDRIE; MITOCONDRIA; Molecular and cellular biology; Molecular genetics; MUTANT; MUTANTES; MUTANTS; Mutation; Nucleic Acid Conformation; NUCLEOTIDE; NUCLEOTIDES; NUCLEOTIDOS; PLASMIDE; PLASMIDIOS; PLASMIDS; Podospora anserina; Repetitive Sequences, Nucleic Acid; Fungi; Plasmid; Mitochondria; Podospora anserina; Ascomycetes; Longevity; Mutation; Genome; Thallophyta
• ISSN: 0021-9258; 1083-351X
• DOI: 10.1016/S0021-9258(18)61646-1

We have identified a novel family of plasmids, each containing very short monomeric units, in Podospora anserina longevity mutants. These plasmids, termed small mitochondrial DNAs (sMt-DNAs), are derived from a highly ordered 368-base pair region of the mitochondrial genome. A total of five direct repeat sequences and seven significant regions of dyad symmetry (i.e. palindromes) were found within a 434-base pair mitochondrial sequence, which includes this 368-base pair region. Mitochondrial DNA rearrangements accompany the formation of these small plasmids indicating their derivation from a plastic region of the mitochondrial genome. A possible relationship between the direct repeat sequences, the palindromic regions, and the excision process is discussed.