Polymerase Chain Reaction (PCR) and direct sequencing of mtDNA from the ND5/6 gene region in Persian sturgeon Acipenser persicus from the southern Caspian Sea

A partial sequence of the mtDNA ND5 gene region was used for population study in Persian sturgeon (west and east areas of southern Caspian Sea). The result showed that although this approach was informative for phylogenetic study in sturgeon, it was less informative for population study in Persian sturgeon

A preliminary study on phylogenetic relationship between five sturgeon species in the Iranian coastline of the Caspian Sea

The phylogenetic relationship of five sturgeon species in the South Caspian Sea was investigated using mtDNA molecule. Sequence analysis of mtDNA D-loop region of five sturgeon species [Great sturgeon (Huso huso), Russian sturgeon (Acipenser gueldenstaedtii), Persian sturgeon (Acipenser persicus), Ship sturgeon (Acipenser nudiventris), Stellate sturgeon (Acipenser stellatus)] and DNA sequencing of two Escherichia coli cloned DNA fragments sized 758 bp and 922 bp was carried out. Sequence comparison of the mtDNA D-loop region between the five sturgeon species showed 100 % sequence identity. However comparison between a short (758 bp) and long (922bp) mtDNA D-loop region within Russian sturgeon showed a 5 bp differences. On the contrary a partial sequence of the mtDNA ND5 gene region showed high sequence and organic base variability in the five species. These results indicate that direct sequencing of ND5 gene provide more information for phylogenetic or population level studies in sturgeon species. The present study revealed a distinct classification among the five sturgeon species. On the basis of the phylogeny tree it is clear that a close evolutionary relationship exists between the great sturgeon and ship sturgeon that was verified in five phylogenetic trees. On the other hand a close resemblance was also seen between Persian and Russian sturgeon indicates that these two species have a closer evolutionary relationship. This study also showed a 2.2 % sequence divergence in sequence data for ND5 gene between Persian sturgeon and Russian sturgeon which indicated that these two species diverged from each other approximately one million years ago. However the verification of this calls for DNA sequencing of different genes

No evidence for presence of maternal mitochondrial DNA in the sperm of Mytilus galloprovincialis males

Species of the mussel family Mytilidae have a special mitochondrial DNA (mtDNA) transmission system, known as doubly uniparental inheritance (DUI), which consists of a maternally inherited (F) and a paternally inherited (M) mitochondrial genome. Females are normally homoplasmic for the F genome and males are heteroplasmic mosaics, with their somatic tissues dominated by the maternal and their gonads dominated by the paternal genome. Several studies have indicated that the maternal genome may often be present in the male germ line. Here we report the results from the examination of mtDNA in pure sperm from more than 30 males of Mytilus galloprovincialis. In all cases, except one, we detected only the M genome. In the sperm of one male, we detected a paternal genome with an F-like primary sequence that was different from the sequence of the maternal genome in the animal's somatic tissues. We conclude that the male germ line is protected against invasion by the maternal genome. This is important because fidelity of gamete-specific transmission of the two mitochondrial genomes is a basic requirement for the stability of DUI