The kalilo Senescence Factor of Neurospora Intermedia: A Mitochondrial is-Element Derived from a Nuclear Plasmid

  • Helmut Bertrand
Part of the Basic Life Sciences book series (BLSC, volume 40)


The wild isolates of Neurospora intermedia from the Hawaiian island of Kauai consist of two classes: (a) “normal” strains that can be propagated virtually indefinitely by serial transfers of asexual spores (conidia), and (b) kalilo strains that go through a process of clonal deterioration and die after a very limited number of transfers, usually fewer than twenty (6). The process leading to vegetative death in kalilo strains has been defined as “senescence.” Senescence is characterized by the appearance of an abnormal stop-start growth phenotype in the mycelium (10) and by a progressive deterioration in mitochondrial functions, including a gradual disappearance of cytochromes aa 3 and b and an accumulation of rearranged mitochondrial chromosomes (mtDNA) (2). The rearrangements in the mtDNAs of senescing kalilo cultures consist primarily of large insertions, deletions, and inversions (2).


Insertion Sequence HindIII Fragment Asexual Spore Wild Isolate Subculture Series 
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  1. 1.
    Bertrand, H. (1983) Aging and senescence in fungi. In Intervention in the Aging Process, Part B; Basic Research and Preclinical Screening, W. Regelson and F.M. Sinex, eds. Alan R. Liss, Inc., New York, pp. 233–251.Google Scholar
  2. 2.
    Bertrand, H., B.S.-S. Chan, and A.J.F. Griffiths (1985) Insertion of a foreign nucleotide sequence into mitochondrial DNA causes senescence in Neurospora intermedia. Cell 41:877–884.PubMedCrossRefGoogle Scholar
  3. 3.
    Bertrand, H., A.J.F. Griffiths, D.A. Court, and CK. Cheng (1986) An extramitochondrial plasmid that is homologous to kalDNA insertion sequences in the mitochondrial chromosome of senescent cells of Neurospora intermedia. Cell (submitted for publication).Google Scholar
  4. 4.
    Bertrand, H., R.A. Collins, L.L. Stohl, R.R. Goewert, and A.M. Lambowitz (1980) Deletion mutants of Neurospora crassa mitochondrial DNA and their relationship to the “start-stop” growth phenotype. Proc. Natl. Acad. Sci., USA 77:6032–6036.PubMedCrossRefGoogle Scholar
  5. 5.
    Burke, J.M., and U.L. Raj Bhandary (1982) Intron within the large rRNA gene of N. crassa mitochondria: A long reading frame and a consensus sequence possibly important in splicing. Cell 31:509–520.PubMedCrossRefGoogle Scholar
  6. 6.
    Griffiths, A.J.F., and H. Bertrand (1984) Unstable cytoplasms in Hawaiian strains of Neurospora intermedia.Curr. Genet. 8:387–398.CrossRefGoogle Scholar
  7. 7.
    Gross, S.R., T. Hsieh, and P.H. Levine (1984) Intramolecular recombination as a source of mitochondrial chromosome heteromorphism in Neurospora. Cell 38:233–239.PubMedCrossRefGoogle Scholar
  8. 8.
    Lewin, B. (1985) Genes II, John Wiley and Sons, New York, pp. 573–645.Google Scholar
  9. 9.
    Osiewacz, H.D., and K. Esser (1984) The mitochondrial plasmid of Podospora anserina: A mobile intron of a mitochondrial gene. Curr. Genet. 8:299–305.CrossRefGoogle Scholar
  10. 10.
    Rieck, A., A.J.F. Griffiths, and H. Bertrand (1982) Mitochondrial variants of Neurospora intermedia from nature. Can. J. Genet. Cytol. 24:741–759.PubMedGoogle Scholar
  11. 11.
    Sanger, F., S. Nicklen, and A.R. Coulsen (1977) DNA sequencing with chain-terminating inhibitors. Proc. Natl. Acad. Sci., USA 74:5463–5467.PubMedCrossRefGoogle Scholar
  12. 12.
    Southern, E.M. (1975) Detection of specific sequences among DNA fragments separated by gel electrophoresis. J. Mol. Biol. 98:503–517.PubMedCrossRefGoogle Scholar
  13. 13.
    Steinhilber, W., and D.J. Cummings (1986) A DNA polymerase activity with characteristics of a reverse transcriptase in Podospora anserina. Curr. Genet. 10:389–392.PubMedCrossRefGoogle Scholar
  14. 14.
    Tzagoloff, A. (1982) The Mitochondrion, Plenum Press, New York.Google Scholar

Copyright information

© Plenum Press, New York 1986

Authors and Affiliations

  • Helmut Bertrand
    • 1
  1. 1.Department of BiologyUniversity of ReginaReginaCanada

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