Doppelt-uniparentale Vererbung (DUI) mitochondrialer DNA bei Muscheln: Biologische Funktion und die Bedeutung von Zellkern/Mitochondrien-Interaktionen für die DUI-Regulierung (Genus Mytilus, Mytilidae, Bivalvia)
Final Report Abstract
Our studies provide evidence that Doubly Uniparental Inheritance (DUI) of mtDNA is involved in reproductive isolation between Mytilus species. This hypothesis is mainly supported by our multiple locus-specific dine shapes along a Baltic sampling transect. We demonstrate strong differences between haplotype frequencies of both M. edulis M and F genome and frequencies of M. edulis specific alleles of three nudear loci. These differences among markers support that reproductive isolation arising from genome-wide incompatibilities is weak, and that these discrepancies possibly result from genetic drift, hybrid zone movement, or marker-specific selection. A common dine centre for M7 lysin (involved in fertilization) and paternally transmitted mtDNA (M. edulis M genome, recombinant mt genome; causing nuclearmitochondrial incompatibilities in hybrids) suggest that these loci may play a role in reproductive isolation. Both M. edulis M genome and recombinant mt genome form strong dines and show restricted gene flow. The recombinant mt genome detected in our study consists of M edulis M genome regulatory sequences in the D-loop. This indicates that nuclear-mitochondrial incompatibility in Mytilus hybrids may not be caused by the interaction between the D-loop and nuclear encoded factors. Instead, interaction between mitochondrial proteins and nuclear encoded factors may be more important. To identify factors involved in DUI regulation and/or reproductive isolation, we applied the approach of selective antibody production. We provide evidence that maternally and paternally transmitted mt genomes are differentially regulated and likely provide different biological functions. The study revealed differences in copy number of M. edulis M genome and recombinant mt genome, relative to maternally transmitted mt genomes between different somatic tissues (posterior adductor muscle, foot) in males. This indicates a tissue-specific regulation and leads to the assumption that both genomes have a different function in males. However, no differences in copy number between M. edulis M genome and recombinant mt genomes were found in males from Hel and Helgoland. We could demonstrate that the copy number of recombinant mt genomes is higher in somatic tissue of Baltic M. trossulus females compared to the copy number of M. edulis M genome in somatic tissue of M. edulis females from Helgoland. This indicates regulatory differences with functional implications between different paternally transmitted mt genomes, at least in females.
Publications
- Mechanisms controlling interspecies gene flow in Baltic Mytilus populations (Bivalvia, Mytilidae). Annual meeting of "Deutsche Zoologische Gesellschaft (DZG)", Münster, September 2006
Stuckas, H., Stoof, K., Quesada, H. & Tiedemann, R.
- Analyses of sperm specific molecules in the Baltic Mytilus hybrid zone [Mytilus edulis, Mytilus trossulus). Museum of Natural History Berlin, Berlin, May 2008
Stuckas, H.
- Detection and characterization of gamete specific molecules in Mytilus edulis using selective antibody production. International workshop "Natural selection and speciation", Johannes Gutenberg University Mainz, February 2008
Stuckas, H., Messerschmidt, K., Putzler, S., Baumann, O., Schenk, J. A., Tiedemann, R. & Micheel, B.
- Reduced introgression of sperm M7 lysin alleles across the Baltic mussel hybrid zone {Mytilus edulis, Mytilus trossulus). International workshop "Natural selection and speciation". Johannes Gutenberg University Mainz, February 2008
Stuckas, H., Stoof, K., Quesada, H. & Tiedemann, R.
- (2009). Detection and characterization of gamete specific molecules in Mytilus edulis using selective antibody production. Molecular Reproduction and Development 76, 4-10
Stuckas, H., Messerschmidt, K., Putzler, S., Baumann, O., Schenk, J.A., Tiedemann, R. & Micheel, B.
- (2009). Evolutionary implications of discordant dines across the Baltic Mytilus hybrid zone (Mytilus edulis, Mytilus trossulus). Heredity 103, 146-156
Stuckas, H., Stoof, K., Quesada, H. & Tiedemann, R.
