Paternal mtDNA and maleness are co-inherited but not causally linked in mytilid mussels.
Ontology highlight
ABSTRACT: Background
In marine mussels of the genus Mytilus there are two mitochondrial genomes. One is transmitted through the female parent, which is the normal transmission route in animals, and the other is transmitted through the male parent which is an unusual phenomenon. In males the germ cell line is dominated by the paternal mitochondrial genome and the somatic cell line by the maternal. Research to date has not allowed a clear answer to the question of whether inheritance of the paternal genome is causally related to maleness.Methodology/principal findings
Here we present results from hybrid crosses, from triploid mussels and from observations of sperm mitochondria in fertilized eggs which clearly show that maleness and presence of the paternal mitochondrial genome can be decoupled. These same results show that the female mussel has exclusive control of whether her progeny will inherit the mitochondrial genome of the male parent.Conclusions/significance
These findings are important in our efforts to understand the mechanistic basis of this unusual mode of mitochondrial DNA inheritance that is common among bivalves.
SUBMITTER: Kenchington EL
PROVIDER: S-EPMC2736565 | biostudies-literature | 2009 Sep
REPOSITORIES: biostudies-literature
Publications
Paternal mtDNA and maleness are co-inherited but not causally linked in mytilid mussels.
Kenchington Ellen L EL Hamilton Lorraine L Cogswell Andrew A Zouros Eleftherios E
PloS one 20090911 9
<h4>Background</h4>In marine mussels of the genus Mytilus there are two mitochondrial genomes. One is transmitted through the female parent, which is the normal transmission route in animals, and the other is transmitted through the male parent which is an unusual phenomenon. In males the germ cell line is dominated by the paternal mitochondrial genome and the somatic cell line by the maternal. Research to date has not allowed a clear answer to the question of whether inheritance of the paternal ...[more]
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