Present address: University of Connecticut Health Center, Department of Biochemistry, Farmington CT06032, USA.
Genetic relationship of 32 cell lines of the Euplotes octocarinatus species complex revealed by random amplified polymorphic DNA (RAPD) fingerprinting
Article first published online: 4 JAN 2002
Volume 8, Issue 12, pages 1971–1979, December 1999
How to Cite
Möllenbeck, M. (1999), Genetic relationship of 32 cell lines of the Euplotes octocarinatus species complex revealed by random amplified polymorphic DNA (RAPD) fingerprinting. Molecular Ecology, 8: 1971–1979. doi: 10.1046/j.1365-294x.1999.00774.x
- Issue published online: 4 JAN 2002
- Article first published online: 4 JAN 2002
- Received 14 November 1998; revision received 8 April 1999;accepted 17 June 1999
- ciliated protozoa;
- genetic diversity;
- mating types;
- random amplified polymorphic DNA (RAPD);
- sibling species;
Random amplified polymorphic DNA (RAPD) fingerprinting was used in this study to determine the genetic relationship of different cell lines of the hypotrichous ciliate Euplotes octocarinatus. Stocks isolated from different habitats in the USA, and from a group of genetically recombined laboratory strains, were characterized. Band-sharing indices (D) for all possible pairwise comparisons revealed a remarkable genetic diversity between the different cell lines. Investigation of the genetic structure in natural populations found diversity — although to a different extent — in all populations investigated. No clonal structure could be observed, as proposed for several protozoa and recently shown for E. daidaleos. These findings suggest frequent conjugation in the populations of E. octocarinatus. No correlation between the genetic relationship of cell lines from different habitats and the distance between the corresponding sampling locations was found. Once separated geographically, the exchange of genetic material between populations appears to be nearly impossible. Therefore, these groups tend to separate into sibling species. The data generally support the occurrence of different syngens in the E. octocarinatus species complex. This finding is in accordance with our observation that the morphological ‘species’ of E. octocarinatus consists of several syngens or sibling species, similar to findings for the Paramecium aurelia-, Tetrahymena pyriformis- and E. vannus-species complexes.