Hotz
Fakultäten » Mathematisch-naturwissenschaftliche Fakultät » Evolutionsbiologie und Umweltwissenschaften, Institut für » Ecology & Environment » Dr. Hansjürg Hotz (ausgetreten) » Hotz
Completed research project
| Title / Titel | Repetitive DNA and germ line genome exclusion in water frog hybrids | ||||||||
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| Abstract (PDF, 14 KB) | |||||||||
| Summary / Zusammenfassung | A majority of the DNA of most eukaryotic organisms consists of multiply repeated sequences without known function. We characterize repetitive DNA in water frogs, in collaboration with Giorgio Mancino and coworkers (Pisa). Results include: (1) An abundant (2.5% of all DNA) tandemly arrayed centromeric satellite DNA is present on several chromosomes of Rana ridibunda, but not or in much lower frequency in Rana lessonae, the second parental species of clonally reproducting hybrids. A role of such centromeric satellites in the germ line genome exclusion of hybrids, although suggested, has not yet been demonstrated. (2) An abundant (10% of all DNA) family of repetitive DNA, similar to SINEs (highly repeated short sequences that occur in clusters interspersed thorughout eukaryotic genomes and are derived via retroposition, in most cases from tRNAs), occurs in clusters of tandemly arrayed repeats throughout all chromosomes of at least 10 species of western Palearctic water frogs but is absent from one African species. Sequence variation among 5 clones of this family from one Rana lessonae and among 2 clones from one Rana ridibunda is not lower than variation between these two species. Further research may reveal implications of this observation for ideas about evolution of SINEs and for effects of clonal inheritance in hybrid lineages on the parental species. |
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| Publications / Publikationen | Ragghianti, M.; Guerrini, F.; Bucci, S.; Mancino, G.; Hotz, H.; Uzzell, T. & Guex, G.-D. (1995): Molecular characterization of a centromeric satellite DNA in the hemiclonal hybrid frog Rana esculenta and its parental species. Chrom. Res. 3: 497-506. | ||||||||
| Keywords / Suchbegriffe | centromere, clonal reproduction, germ line, hybridogenesis, Rana esculenta group, repetitive DNA, satellite DNA, SINE-like retroposon | ||||||||
| Project leadership and contacts / Projektleitung und Kontakte |
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| Funding source(s) / Unterstützt durch |
SNF (Personen- und Projektförderung) |
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| In collaboration with / In Zusammenarbeit mit |
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| Duration of Project / Projektdauer | to Dec 2005 |