BACKGROUND AND AIMS: Archipelagos provide a valuable framework for investigating phenotypic evolution under different levels of geographical isolation. Here, we analysed two co-distributed, widespread plant lineages to examine if incipient island differentiation follows parallel patterns of variation in traits related to dispersal and colonization. METHODS: Twenty-one populations of two anemochorous Canarian endemics, Kleinia neriifolia and Periploca laevigata, were sampled to represent mainland congeners and two contrasting exposures across all the main islands. Leaf size, seed size and dispersability (estimated as diaspore terminal velocity) were characterized in each population. For comparison, dispersability was also measured in four additional anemochorous island species. Plastid DNA data were used to infer genetic structure and to reconstruct the phylogeographical pattern of our focal species. KEY RESULTS: In both lineages, mainland-island phenotypic divergence probably started within a similar time frame (i.e. Plio-Pleistocene). Island colonization implied parallel increases in leaf size and dispersability, but seed size showed opposite patterns of variation between Kleinia and Periploca species pairs. Furthermore, dispersability in our focal species was low when compared with other island plants, mostly due to large diaspore sizes. At the archipelago scale, island exposure explained a significant variation in leaf size across islands, but not in dispersability or seed size. Combined analyses of genetic and phenotypic data revealed two consistent patterns: (1) extensive within-island but very limited among-island dispersal, and (2) recurrent phenotypic differentiation between older (central) and younger (peripheral) island populations. CONCLUSIONS: Leaf size follows a more predictable pattern than dispersability, which is affected by stochastic shifts in seed size. Increased dispersability is associated with high population connectivity at the island scale, but does not preclude allopatric divergence among islands. In sum, phenotypic convergent patterns between species suggest a major role of selection, but deviating traits also indicate the potential contribution of random processes, particularly on peripheral islands.

• MeSH
• Asteraceae * MeSH
• biologická evoluce * MeSH
• distribuce rostlin * MeSH
• fylogeografie MeSH
• ostrovy MeSH
• Periploca * MeSH
• zvláštnosti životní historie * MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Geografické názvy
• ostrovy MeSH
• Španělsko MeSH

Here, we present a comprehensive analysis of the H5N8/H5N5 highly pathogenic avian influenza (HPAI) virus strains detected in the Czech Republic during an outbreak in 2017. Network analysis of the H5 Hemagglutinin (HA) from 99% of the outbreak localities suggested that the diversity of the Czech H5N8/H5N5 viruses was influenced by two basic forces: local microevolution and independent incursions. The geographical occurrence of the central node H5 HA sequences revealed three eco-regions, which apparently played an important role in the origin and further spread of the local H5N8/HPAI variants across the country. A plausible explanation for the observed pattern of diversity is also provided.

• MeSH
• epidemický výskyt choroby MeSH
• fylogeneze MeSH
• genetická variace MeSH
• hemaglutininové glykoproteiny viru chřipky genetika   MeSH
• molekulární evoluce * MeSH
• ptačí chřipka u ptáků epidemiologie   virologie   MeSH
• ptáci klasifikace   virologie   MeSH
• virulence MeSH
• virus chřipky A, podtyp H5N8 klasifikace   genetika   izolace a purifikace   patogenita   MeSH
• virus chřipky A klasifikace   genetika   izolace a purifikace   patogenita   MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Geografické názvy
• Česká republika epidemiologie   MeSH

We used the mitochondrial control region and nuclear microsatellites to assess the distribution patterns, population structure, demography and landscape genetics for the hedgehogs Erinaceus europaeus and Erinaceus roumanicus in a transect of the mid-European zone of sympatry. E. roumanicus was less frequent and restricted to regions with lower altitudes. Demographic analyses suggested recent population growth in this species. A comparison of patterns in the spatial variability of mitochondrial and nuclear DNA indicated less sex-biased dispersal and higher levels of gene flow in E. roumanicus. No evidence of recent hybridisation or introgression was detected. We interpreted these results by comparing with phylogeographic and palaeontological studies as well as with the occurrence of hybridisation in the Russian contact zone. We propose that Central Europe was colonised by E. roumanicus by the beginning of the Neolithic period and that there was a subsequent reinforcement stage as well as the formation of a zone of sympatry after the complete reproductive isolation of both species.

• MeSH
• demografie MeSH
• fylogeografie MeSH
• genetická variace MeSH
• haplotypy MeSH
• ježkovití genetika   MeSH
• mikrosatelitní repetice MeSH
• mitochondriální DNA MeSH
• populační genetika MeSH
• reprodukční izolace MeSH
• sympatrie MeSH
• tok genů MeSH
• zvířata MeSH
• Check Tag
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Geografické názvy
• Evropa MeSH

• MeSH
• DNA bakterií chemie   MeSH
• lidé MeSH
• meningokoková meningitida epidemiologie   genetika   mikrobiologie   MeSH
• molekulární evoluce MeSH
• Neisseria meningitidis genetika   MeSH
• polymerázová řetězová reakce MeSH
• Check Tag
• lidé MeSH
• Geografické názvy
• Česká republika MeSH

SARS-CoV-2 has accumulated many mutations since its emergence in late 2019. Nucleotide substitutions leading to amino acid replacements constitute the primary material for natural selection. Insertions, deletions, and substitutions appear to be critical for coronavirus's macro- and microevolution. Understanding the molecular mechanisms of mutations in the mutational hotspots (positions, loci with recurrent mutations, and nucleotide context) is important for disentangling roles of mutagenesis and selection. In the SARS-CoV-2 genome, deletions and insertions are frequently associated with repetitive sequences, whereas C>U substitutions are often surrounded by nucleotides resembling the APOBEC mutable motifs. We describe various approaches to mutation spectra analyses, including the context features of RNAs that are likely to be involved in the generation of recurrent mutations. We also discuss the interplay between mutations and natural selection as a complex evolutionary trend. The substantial variability and complexity of pipelines for the reconstruction of mutations and the huge number of genomic sequences are major problems for the analyses of mutations in the SARS-CoV-2 genome. As a solution, we advocate for the development of a centralized database of predicted mutations, which needs to be updated on a regular basis.

• MeSH
• COVID-19 * genetika   MeSH
• lidé MeSH
• mutace MeSH
• mutageneze MeSH
• nukleotidy MeSH
• SARS-CoV-2 genetika   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• přehledy MeSH

A novel virus infecting elderberry was identified by high-throughput Illumina sequencing of double strand RNAs isolated form elderberry leaves. The complete genome sequence obtained (4512 nucleotides in length) shows an organization typical for aureusviruses, with five open reading frames (ORFs) and the typical ORF1-RT expression by the readthrough of an amber stop codon. The analysis of the RNA-dependent RNA polymerase (RdRp) and coat protein (CP) sequences showed the highest identity (respectively 75.7% and 55%) with the corresponding amino acid sequences of Pothos latent virus. These two values, below the species demarcation criteria for the genus, indicate that the detected virus is a new member of genus Aureusvirus, family Tombusviridae, with the proposed name Elderberry aureusvirus 1 (ElAV1). A survey confirmed the wide distribution of ElAV1 in elderberry in the Czech Republic. Phylogenetic analyses of RdRp and CP sequences showed distinct microevolution of geographically separated isolates, with a tendency for isolates coming from close localities or from the same region to cluster together but heterogeneity of viral populations down to a local scale was also observed. The symptomatology of the new virus is not fully clear, but many infected trees were either asymptomatic or showed mild chlorotic mosaics. More severe symptoms, potentially impacting yields of flowers or berries, were observed in plants with mixed infections of ElAV1 and other elderberry viruses. Further efforts are now needed to determine ElAV1 prevalence outside the Czech Republic and to unravel its epidemiology.

• MeSH
• bez černý virologie   MeSH
• fylogeneze MeSH
• genom virový * MeSH
• nemoci rostlin virologie   MeSH
• Tombusviridae klasifikace   genetika   izolace a purifikace   MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

Here, we present a study of the population genetic architecture and microevolution of the Egyptian fruit bat (Rousettus aegyptiacus) at the environmental margins in the Middle East using mitochondrial sequences and nuclear microsatellites. In contrast to the rather homogenous population structure typical of cave-dwelling bats in climax tropical ecosystems, a relatively pronounced isolation by distance and population diversification was observed. The evolution of this pattern could be ascribed to the complicated demographic history at higher latitudes related to the range margin fragmentation and complex geomorphology of the studied area. Lineages from East Africa and Arabia show divergent positions. Within the northwestern unit, the most marked pattern of the microsatellite data set is connected with insularity, as demonstrated by the separate status of populations from Saharan oases and Cyprus. These demes also exhibit a reduction in genetic variability, which is presumably connected with founder effects, drift and other potential factors related to island evolution as site-specific selection. Genetic clustering indicates a semipermeability of the desert barriers in the Sahara and Arabian Peninsula and a corridor role of the Nile Valley. The results emphasize the role of the island environment in restricting the gene flow in megabats, which is also corroborated by biogeographic patterns within the family, and suggests the possibility of nascent island speciation on Cyprus. Demographic analyses suggest that the colonization of the region was connected to the spread of agricultural plants; therefore, the peripatric processes described above might be because of or strengthened by anthropogenic changes in the environment.

• MeSH
• Bayesova věta MeSH
• Chiroptera genetika   MeSH
• genetická variace MeSH
• genotyp MeSH
• mikrosatelitní repetice MeSH
• mitochondriální DNA genetika   MeSH
• molekulární evoluce * MeSH
• molekulární sekvence - údaje MeSH
• ostrovy MeSH
• populační genetika * MeSH
• sekvenční analýza DNA MeSH
• shluková analýza MeSH
• tok genů MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Geografické názvy
• ostrovy MeSH
• Střední východ MeSH
• východní Afrika MeSH

Mixed infections and heteroresistance of Helicobacter pylori contribute to decreased efficacy of treatments. This study aimed to investigate frequency of clarithromycin heteroresistance and its link with mixed infections, medication history, and disease severity. A total of 40 pairs of H. pylori strains were isolated from the antrum and corpus of 97 patients. Susceptibility of the strains to clarithromycin was measured by agar dilution method. Site-specific mutations of 23S rRNA at A2143G, A2142G, and A2142C positions were analyzed by PCR and genomic relatedness of pairs of the strains was determined by random amplified polymorphic DNA (RAPD)-PCR. The results showed a prevalence of 35% (14/40) clarithromycin resistance. Diversity of the antrum and corpus isolates in resistance to clarithromycin was detected among 17.5% (7/40) of the patients. Similarly, diversity in MIC value was also detected in two patients infected with the sensitive strains. Significant difference in frequency of resistance was detected among patients with peptic ulcer disease (PUD) (MIC90 32 μg/mL) and severe gastritis (MIC90 16 μg/mL), compared with those who suffered from non-ulcer dyspepsia (NUD) (MIC90 8 μg/mL) and chronic gastritis (MIC90 0.25 μg/mL). MIC values showed 8-32 folds increased levels in the corpus. A2142G, A2143G, and A2142C mutations were detected in three, two, and two patients, respectively, but not observed in 46% of the resistant strains. RAPD-PCR fingerprints showed identical molecular patterns for the isolates of the corpus and antrum in each patient. In conclusion, microevolution of H. pylori strains during chronic infection, rather than mixed infection, and inappropriate medication appear to be main reasons of treatment failure in adults.

• MeSH
• antibakteriální látky farmakologie   MeSH
• bakteriální léková rezistence * účinky léků   genetika   MeSH
• dítě MeSH
• dospělí MeSH
• genetická variace MeSH
• Helicobacter pylori účinky léků   genetika   izolace a purifikace   MeSH
• infekce vyvolané Helicobacter pylori mikrobiologie   patologie   MeSH
• klarithromycin farmakologie   MeSH
• lidé středního věku MeSH
• lidé MeSH
• mikrobiální testy citlivosti MeSH
• mladiství MeSH
• mladý dospělý MeSH
• mutace MeSH
• polymerázová řetězová reakce MeSH
• RNA ribozomální 23S genetika   MeSH
• senioři MeSH
• žaludek mikrobiologie   MeSH
• Check Tag
• dítě MeSH
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• mladiství MeSH
• mladý dospělý MeSH
• mužské pohlaví MeSH
• senioři MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• Geografické názvy
• Írán MeSH

• MeSH
• sociální chování MeSH

• Konspekt
• Společenské vědy
• NLK Obory
• sociologie

• MeSH
• biologie MeSH
• Publikační typ
• monografie MeSH

• Konspekt
• Obecná biologie
• NLK Obory
• biologie