phylogenetics
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elektronický časopis
- MeSH
- biologická evoluce MeSH
- druhová specificita MeSH
- fylogeneze MeSH
- genetický kód MeSH
- sekvence nukleotidů MeSH
- Konspekt
- Obecná genetika. Obecná cytogenetika. Evoluce
- NLK Obory
- biologie
- genetika, lékařská genetika
- biologie
- NLK Publikační typ
- elektronické časopisy
Ants in the genera Anochetus and Odontomachus belong to one of the largest clades in the subfamily Ponerinae, and are one of four lineages of ants possessing spring-loaded "trap-jaws." Here we present results from the first global species-level molecular phylogenetic analysis of these trap-jaw ants, reconstructed from one mitochondrial, one ribosomal RNA, and three nuclear protein-coding genes. Bayesian and likelihood analyses strongly support reciprocal monophyly for the genera Anochetus and Odontomachus. Additionally, we found strong support for seven trap-jaw ant clades (four in Anochetus and three in Odontomachus) mostly concordant with geographic distribution. Ambiguity remains concerning the closest living non-trap-jaw ant relative of the Anochetus+Odontomachus clade, but Bayes factor hypothesis testing strongly suggests that trap-jaw ants evolved from a short mandible ancestor. Ponerine trap-jaw ants originated in the early Eocene (52.5Mya) in either South America or Southeast Asia, where they have radiated rapidly in the last 30million years, and subsequently dispersed multiple times to Africa and Australia. These results will guide future taxonomic work on the group and act as a phylogenetic framework to study the macroevolution of extreme ant mouthpart specialization.
- MeSH
- Bayesova věta MeSH
- cytochromy b klasifikace genetika metabolismus MeSH
- Formicidae klasifikace genetika MeSH
- fylogeneze MeSH
- fylogeografie MeSH
- genetická variace MeSH
- RNA ribozomální 28S klasifikace genetika metabolismus MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Geografické názvy
- Afrika MeSH
- Austrálie MeSH
- jihovýchodní Asie MeSH
- Jižní Amerika MeSH
Peridinialean dinophytes include a unique evolutionary group of algae harboring a diatom as an endosymbiont (Kryptoperidiniaceae), whose phylogenetic origin and internal relationships are not fully resolved at present. Several interpretations of the thecal plate pattern present in Durinskia oculata currently compete and lead to considerable taxonomic confusion. Moreover, it is unclear at present whether the species is restricted to freshwater habitats, or occurs in the marine environment as well. We collected material at the type locality of D. oculata in the Czech Republic and established monoclonal strains. Dinophyte cells were studied using light and electron microscopy, and we also determined DNA sequences of several rRNA regions (including the Internal Transcribed Spacers) for molecular characterization and phylogenetics. The morphology of strain GeoM∗662 indicated a plate formula of Po, X, 4', 2a, 6″, 5c, 5s, 5‴, 2⁗, which was sustained also in form of a microscopic slide serving as an epitype. In the molecular DNA tree based on a matrix composed of concatenated rRNA sequences, strain GeoM∗662 showed a close relationship to other species of Durinskia, and the freshwater species clearly differs from the marine members. Two independent colonization events from the marine into the freshwater environment can be inferred within the Kryptoperidiniaceae. We provide a summarizing cladogram of dinophytes harboring a diatom as endosymbiont with evolutionary novelties indicated as well as a morphological key to the 6 species of Durinskia that are currently accepted.
- MeSH
- fylogeneze MeSH
- pravděpodobnostní funkce MeSH
- RNA ribozomální chemie genetika MeSH
- rozsivky cytologie genetika MeSH
- sekvenční analýza DNA MeSH
- Publikační typ
- časopisecké články MeSH
- Geografické názvy
- Česká republika MeSH
xiv, 333 s. : il. ; 27 cm
- MeSH
- genetika MeSH
- molekulární evoluce MeSH
- Publikační typ
- monografie MeSH
- Konspekt
- Biologické vědy
- NLK Obory
- genetika, lékařská genetika
- biologie
The presence of a nucleus and other membrane-bounded intracellular compartments is the defining feature of eukaryotic cells. Endosymbiosis accounts for the origins of mitochondria and plastids, but the evolutionary ancestry of the remaining cellular compartments is incompletely documented. Resolving the evolutionary history of organelle-identity encoding proteins within the endomembrane system is a necessity for unravelling the origins and diversification of the endogenously derived organelles. Comparative genomics reveals events after the last eukaryotic common ancestor (LECA), but resolution of events prior to LECA, and a full account of the intracellular compartments present in LECA, has proved elusive. We have devised and exploited a new phylogenetic strategy to reconstruct the history of the Rab GTPases, a key family of endomembrane-specificity proteins. Strikingly, we infer a remarkably sophisticated organellar composition for LECA, which we predict possessed as many as 23 Rab GTPases. This repertoire is significantly greater than that present in many modern organisms and unexpectedly indicates a major role for secondary loss in the evolutionary diversification of the endomembrane system. We have identified two Rab paralogues of unknown function but wide distribution, and thus presumably ancient nature; RabTitan and RTW. Furthermore, we show that many Rab paralogues emerged relatively suddenly during early metazoan evolution, which is in stark contrast to the lack of significant Rab family expansions at the onset of most other major eukaryotic groups. Finally, we reconstruct higher-order ancestral clades of Rabs primarily linked with endocytic and exocytic process, suggesting the presence of primordial Rabs associated with the establishment of those pathways and giving the deepest glimpse to date into pre-LECA history of the endomembrane system.
- MeSH
- eukaryotické buňky klasifikace enzymologie MeSH
- fylogeneze MeSH
- intracelulární membrány enzymologie MeSH
- klasifikace metody MeSH
- lidé MeSH
- molekulární evoluce MeSH
- molekulární sekvence - údaje MeSH
- rab proteiny vázající GTP genetika metabolismus MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- hodnotící studie MeSH
- práce podpořená grantem MeSH
We have revisited the mtDNA phylogeny of the bank vole Clethrionomys glareolus based on Sanger and next-generation Illumina sequencing of 32 complete mitochondrial genomes. The bank vole is a key study species for understanding the response of European fauna to the climate change following the Last Glacial Maximum (LGM) and one of the most convincing examples of a woodland mammal surviving in cryptic northern glacial refugia in Europe. The genomes sequenced included multiple representatives of each of the eight bank vole clades previously described based on cytochrome b (cob) sequences. All clades with the exception of the Basque - likely a misidentified pseudogene clade - were highly supported in all phylogenetic analyses and the relationships between the clades were resolved with high confidence. Our data extend the distribution of the Carpathian clade, the marker of a northern glacial refugium in the Carpathian Mountains, to include Britain and Fennoscandia (but not adjacent areas of continental Europe). The Carpathian sub-clade that colonized Britain and Fennoscandia had a somewhat different history from the sub-clade currently found in or close to the Carpathians and may have derived from a more north-westerly refugial area. The two bank vole populations that colonized Britain at the end of the last glaciation are for the first time linked with particular continental clades, the first colonists with the Carpathian clade and the second colonists with the western clade originating in a more southerly refugium in the vicinity of the Alps. We however found no evidence that a functional divergence of proteins encoded in the mitochondrial genome promoted the partial genetic replacement of the first colonists by the second colonists detected previously in southern Britain. We did identify one codon site that changed more often and more radically in the tree than expected and where the observed amino acid change may affect the reductase activity of the cytochrome bc1 complex, but the change was not specific to a particular clade. We also found an excess of radical changes to the primary protein structure for geographically restricted clades from southern Italy and Norway, respectively, possibly related to stronger selective pressure at the latitudinal extremes of the bank vole distribution. However, overall, we find little evidence of pervasive effects of deviation from neutrality on bank vole mtDNA phylogeography.
- MeSH
- Arvicolinae klasifikace genetika MeSH
- Bayesova věta MeSH
- biologická evoluce * MeSH
- cytochromy b genetika MeSH
- fylogeneze * MeSH
- fylogeografie MeSH
- genetická variace MeSH
- genom mitochondriální MeSH
- klimatické změny MeSH
- mitochondriální DNA genetika MeSH
- modely genetické MeSH
- pravděpodobnostní funkce MeSH
- sekvenční analýza DNA MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Geografické názvy
- Evropa MeSH
The two stork species that nest in Central Europe, Ciconia ciconia and Ciconia nigra, have been repeatedly shown to host the digenetic trematode Cathaemasia hians (Rudolphi, 1809) in their esophagus and muscular stomach. These host species differ in their habitat and food preferences, and the morphologic characters of C. hians isolates ex Ci. nigra and Ci. ciconia are not identical. These differences led to a previous proposal of two subspecies, Cathaemasia hians longivitellata Macko, 1960, and Cathaemasia hians hians Macko, 1960. We hypothesize that the Cathaemasia hians isolates ex Ci. nigra and Ci. ciconia represent two independent species. Therefore, in the present study, we performed the first molecular analyses of C. hians individuals that were consistent with the diagnosis of C. hians hians (ex Ci. nigra) and C. hians longivitellata (ex Ci. ciconia). The combined molecular and comparative morphological analyses of the central European Cathaemasia individuals ex Ci. nigra and Ci. ciconia led to the proposal of a split of C. hians into C. hians sensu stricto (formerly C. hians hians) and C. longivitellata sp. n. (formerly C. hians longivitellata). Morphological analyses confirmed that the length of the vitellaria is the key identification feature of the two previously mentioned species. Both Cathaemasia spp. substantially differ at the molecular level and have strict host specificity, which might be related to differences in the habitat and food preferences of the two stork species.
Malacosporeans represent a small fraction of myxozoan biodiversity with only two genera and three species described. They cycle between bryozoans and freshwater fish. In this study, we (i) microscopically examine and screen different freshwater/marine fish species from various geographic locations and habitats for the presence of malacosporeans using PCR; (ii) study the morphology, prevalence, host species/habitat preference and distribution of malacosporeans; (iii) perform small subunit/large subunit rDNA and Elongation factor 2 based phylogenetic analyses of newly gathered data, together with all available malacosporean data in GenBank; and (iv) investigate the evolutionary trends of malacosporeans by mapping the morphology of bryozoan-related stages, host species, habitat and geographic data on the small subunit rDNA-based phylogenetic tree. We reveal a high prevalence and diversity of malacosporeans in several fish hosts in European freshwater habitats by adding five new species of Buddenbrockia and Tetracapsuloides from cyprinid and perciform fishes. Comprehensive phylogenetic analyses revealed that, apart from Buddenbrockia and Tetracapsuloides clades, a novel malacosporean lineage (likely a new genus) exists. The fish host species spectrum was extended for Buddenbrockia plumatellae and Buddenbrockia sp. 2. Co-infections of up to three malacosporean species were found in individual fish. The significant increase in malacosporean species richness revealed in the present study points to a hidden biodiversity in this parasite group. This is most probably due to the cryptic nature of malacosporean sporogonic and presporogonic stages and mostly asymptomatic infections in the fish hosts. The potential existence of malacosporean life cycles in the marine environment as well as the evolution of worm- and sac-like morphology is discussed. This study improves the understanding of the biodiversity, prevalence, distribution, habitat and host preference of malacosporeans and unveils their evolutionary trends.
- MeSH
- biodiverzita * MeSH
- biologická evoluce * MeSH
- elongační faktor 2 genetika MeSH
- molekulární sekvence - údaje MeSH
- Myxozoa klasifikace cytologie genetika MeSH
- protozoální DNA genetika MeSH
- ribozomální DNA chemie genetika MeSH
- RNA ribozomální 18S genetika MeSH
- RNA ribozomální genetika MeSH
- ryby parazitologie MeSH
- sekvenční analýza DNA MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Mitochondrial genomes are readily sequenced with recent technology and thus evolutionary lineages can be densely sampled. This permits better phylogenetic estimates and assessment of potential biases resulting from heterogeneity in nucleotide composition and rate of change. We gathered 245 mitochondrial sequences for the Coleoptera representing all 4 suborders, 15 superfamilies of Polyphaga, and altogether 97 families, including 159 newly sequenced full or partial mitogenomes. Compositional heterogeneity greatly affected 3rd codon positions, and to a lesser extent the 1st and 2nd positions, even after RY coding. Heterogeneity also affected the encoded protein sequence, in particular in the nad2, nad4, nad5, and nad6 genes. Credible tree topologies were obtained with the nhPhyML ("nonhomogeneous") algorithm implementing a model for branch-specific equilibrium frequencies. Likelihood searches using RAxML were improved by data partitioning by gene and codon position. Finally, the PhyloBayes software, which allows different substitution processes for amino acid replacement at various sites, produced a tree that best matched known higher level taxa and defined basal relationships in Coleoptera. After rooting with Neuropterida outgroups, suborder relationships were resolved as (Polyphaga (Myxophaga (Archostemata + Adephaga))). The infraorder relationships in Polyphaga were (Scirtiformia (Elateriformia ((Staphyliniformia + Scarabaeiformia) (Bostrichiformia (Cucujiformia))))). Polyphagan superfamilies were recovered as monophyla except Staphylinoidea (paraphyletic for Scarabaeiformia) and Cucujoidea, which can no longer be considered a valid taxon. The study shows that, although compositional heterogeneity is not universal, it cannot be eliminated for some mitochondrial genes, but dense taxon sampling and the use of appropriate Bayesian analyses can still produce robust phylogenetic trees.
- MeSH
- brouci klasifikace genetika MeSH
- fylogeneze * MeSH
- genetická heterogenita * MeSH
- genom hmyzu * MeSH
- genom mitochondriální * MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH