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Journal article

Chromatin diminution leads to rapid evolutionary changes in the organization of the germ line genomes of the parasitic nematodes A. suum and P. univalens

  • Bachmann-Waldmann, Christa Zoology, Departement of Biology, University of Fribourg, Switzerland
  • Jentsch, Stephan Zoology, Departement of Biology, University of Fribourg, Switzerland
  • Tobler, Heinz Zoology, Departement of Biology, University of Fribourg, Switzerland
  • Müller, Fritz Zoology, Departement of Biology, University of Fribourg, Switzerland
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    04.12.2004
Published in:
  • Molecular and Biochemical Parasitology. - 2004, vol. 134, no. 1, p. 53-64
Ascaris suum
Parascaris univalens
chromatin diminution
genome evolution
English Chromatin diminution in the parasitic nematodes Ascaris suum and Parascaris univalens represents a rather complex molecular phenomenon that includes chromosomal breakage, DNA degradation and new telomere formation. At a given elimination site, DNA breakage and new telomere addition does not take place at a single chromosomal locus but at many different places within a several kilobase long chromosomal region, referred to as chromosomal breakage region (CBR). Here we describe the cloning and the characterisation of seven CBRs from A. suum and P. univalens and we show that the process has been conserved between the two species. A detailed sequence comparison provides evidence that the sequences of the CBRs and their flanking regions are not directly important for the specification of the elimination sites. Six out of the seven CBRs are conserved between the two nematode species, suggesting that they have already existed in a common ancestor. We present a hypothesis stating that the elimination process ensures the maintenance of a functional somatic genome and concomitantly allows extremely rapid and profound changes in the germ line genome, thereby allowing the development of new germ line specific functions and thus providing a selective advantage for the chromatin eliminating nematodes during further evolution.
Faculty
Faculté des sciences et de médecine
Department
Département de Biologie
Language
  • English
Classification
Biological sciences
License
License undefined
Identifiers
Persistent URL
https://folia.unifr.ch/unifr/documents/299795
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