• MeSH
• nemoci štítné žlázy etiologie   chirurgie   MeSH
• tyreoidektomie MeSH

BACKGROUND: Downy mildews are the most speciose group of oomycetes and affect crops of great economic importance. So far, there is only a single deeply-sequenced downy mildew genome available, from Hyaloperonospora arabidopsidis. Further genomic resources for downy mildews are required to study their evolution, including pathogenicity effector proteins, such as RxLR effectors. Plasmopara halstedii is a devastating pathogen of sunflower and a potential pathosystem model to study downy mildews, as several Avr-genes and R-genes have been predicted and unlike Arabidopsis downy mildew, large quantities of almost contamination-free material can be obtained easily. RESULTS: Here a high-quality draft genome of Plasmopara halstedii is reported and analysed with respect to various aspects, including genome organisation, secondary metabolism, effector proteins and comparative genomics with other sequenced oomycetes. Interestingly, the present analyses revealed further variation of the RxLR motif, suggesting an important role of the conservation of the dEER-motif. Orthology analyses revealed the conservation of 28 RxLR-like core effectors among Phytophthora species. Only six putative RxLR-like effectors were shared by the two sequenced downy mildews, highlighting the fast and largely independent evolution of two of the three major downy mildew lineages. This is seemingly supported by phylogenomic results, in which downy mildews did not appear to be monophyletic. CONCLUSIONS: The genome resource will be useful for developing markers for monitoring the pathogen population and might provide the basis for new approaches to fight Phytophthora and downy mildew pathogens by targeting core pathogenicity effectors.

• MeSH
• biologická evoluce MeSH
• faktory virulence genetika   MeSH
• fosfolipidy metabolismus   MeSH
• fungální proteiny MeSH
• fylogeneze MeSH
• genom fungální * MeSH
• genomika metody   MeSH
• Helianthus mikrobiologie   MeSH
• heterozygot MeSH
• mikrosatelitní repetice MeSH
• oomycety klasifikace   genetika   metabolismus   MeSH
• Phytophthora genetika   MeSH
• promotorové oblasti (genetika) MeSH
• repetitivní sekvence nukleových kyselin MeSH
• sekundární metabolismus MeSH
• signální transdukce MeSH
• stanovení celkové genové exprese MeSH
• Publikační typ
• časopisecké články MeSH

Ticks and the pathogens they transmit constitute a growing burden for human and animal health worldwide. Traditionally, tick-borne pathogen detection has been carried out using PCR-based methods that rely in known sequences for specific primers design. This approach matches with the view of a 'single-pathogen' epidemiology. Recent results, however, have stressed the importance of coinfections in pathogen ecology and evolution with impact in pathogen transmission and disease severity. New approaches, including high-throughput technologies, were then used to detect multiple pathogens, but they all need a priori information on the pathogens to search. Thus, those approaches are biased, limited and conceal the complexity of pathogen ecology. Currently, next generation sequencing (NGS) is applied to tick-borne pathogen detection as well as to study the interactions between pathogenic and non-pathogenic microorganisms associated to ticks, the pathobiome. The use of NGS technologies have surfaced two major points: (i) ticks are associated to complex microbial communities and (ii) the relation between pathogens and microbiota is bidirectional. Notably, a new challenge emerges from NGS experiments, data analysis. Discovering associations among a high number of microorganisms is not trivial and therefore most current NGS studies report lists of microorganisms without further insights. An alternative to this is the combination of NGS with analytical tools such as network analysis to unravel the structure of microbial communities associated to ticks in different ecosystems.

• MeSH
• Bacteria izolace a purifikace   MeSH
• interakce hostitele a patogenu MeSH
• klíšťata mikrobiologie   MeSH
• koinfekce mikrobiologie   MeSH
• lidé MeSH
• mikrobiální interakce MeSH
• mikrobiota * MeSH
• nemoci přenášené klíšťaty diagnóza   mikrobiologie   MeSH
• vysoce účinné nukleotidové sekvenování MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• přehledy MeSH

BACKGROUND: Gene duplication has led to a most remarkable adaptation involved in vertebrates' host-pathogen arms-race, the major histocompatibility complex (MHC). However, MHC duplication history is as yet poorly understood in non-mammalian vertebrates, including birds. RESULTS: Here, we provide evidence for the evolution of two ancient avian MHC class IIB (MHCIIB) lineages by a duplication event prior to the radiation of all extant birds >100 million years ago, and document the role of concerted evolution in eroding the footprints of the avian MHCIIB duplication history. CONCLUSIONS: Our results suggest that eroded footprints of gene duplication histories may mimic birth-death evolution and that in the avian MHC the presence of the two lineages may have been masked by elevated rates of concerted evolution in several taxa. Through the presence of a range of intermediate evolutionary stages along the homogenizing process of concerted evolution, the avian MHCIIB provides a remarkable illustration of the erosion of multigene family duplication history.

• MeSH
• duplikace genu MeSH
• geny MHC třídy II genetika   MeSH
• molekulární evoluce * MeSH
• multigenová rodina genetika   MeSH
• ptáci genetika   MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

Pathogenic uncultivable treponemes, similar to syphilis-causing Treponema pallidum subspecies pallidum, include T. pallidum ssp. pertenue, T. pallidum ssp. endemicum and Treponema carateum, which cause yaws, bejel and pinta, respectively. Genetic analyses of these pathogens revealed striking similarity among these bacteria and also a high degree of similarity to the rabbit pathogen, Treponema paraluiscuniculi, a treponeme not infectious to humans. Genome comparisons between pallidum and non-pallidum treponemes revealed genes with potential involvement in human infectivity, whereas comparisons between pallidum and pertenue treponemes identified genes possibly involved in the high invasivity of syphilis treponemes. Genetic variability within syphilis strains is considered as the basis of syphilis molecular epidemiology with potential to detect more virulent strains, whereas genetic variability within a single strain is related to its ability to elude the immune system of the host. Genome analyses also shed light on treponemal evolution and on chromosomal targets for molecular diagnostics of treponemal infections.

• MeSH
• faktory virulence MeSH
• frambézie diagnóza   mikrobiologie   MeSH
• genetická variace MeSH
• králíci MeSH
• lidé MeSH
• molekulární evoluce MeSH
• molekulární typizace MeSH
• syfilis diagnóza   mikrobiologie   MeSH
• Treponema pallidum klasifikace   genetika   patogenita   MeSH
• zvířata MeSH
• Check Tag
• králíci MeSH
• lidé MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• přehledy MeSH

Anticipating how epidemics will spread across landscapes requires understanding host dispersal events that are notoriously difficult to measure. Here, we contrast host and virus genetic signatures to resolve the spatiotemporal dynamics underlying geographic expansions of vampire bat rabies virus (VBRV) in Peru. Phylogenetic analysis revealed recent viral spread between populations that, according to extreme geographic structure in maternally inherited host mitochondrial DNA, appeared completely isolated. In contrast, greater population connectivity in biparentally inherited nuclear microsatellites explained the historical limits of invasions, suggesting that dispersing male bats spread VBRV between genetically isolated female populations. Host nuclear DNA further indicated unanticipated gene flow through the Andes mountains connecting the VBRV-free Pacific coast to the VBRV-endemic Amazon rainforest. By combining Bayesian phylogeography with landscape resistance models, we projected invasion routes through northern Peru that were validated by real-time livestock rabies mortality data. The first outbreaks of VBRV on the Pacific coast of South America could occur by June 2020, which would have serious implications for agriculture, wildlife conservation, and human health. Our results show that combining host and pathogen genetic data can identify sex biases in pathogen spatial spread, which may be a widespread but underappreciated phenomenon, and demonstrate that genetic forecasting can aid preparedness for impending viral invasions.

• MeSH
• Bayesova věta MeSH
• biologická evoluce * MeSH
• Chiroptera virologie   MeSH
• genom virový MeSH
• interakce hostitele a patogenu * MeSH
• mikrosatelitní repetice genetika   MeSH
• roční období MeSH
• typy dědičnosti genetika   MeSH
• virus vztekliny genetika   MeSH
• vzteklina epidemiologie   MeSH
• zeměpis MeSH
• zvířata MeSH
• Check Tag
• mužské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Research Support, U.S. Gov't, Non-P.H.S. MeSH
• Geografické názvy
• Peru epidemiologie   MeSH

Parasitic trypanosomatids diverged from free-living kinetoplastid ancestors several hundred million years ago. These parasites are relatively well known, due in part to several unusual cell biological and molecular traits and in part to the significance of a few - pathogenic Leishmania and Trypanosoma species - as aetiological agents of serious neglected tropical diseases. However, the majority of trypanosomatid biodiversity is represented by osmotrophic monoxenous parasites of insects. In two lineages, novymonads and strigomonads, osmotrophic lifestyles are supported by cytoplasmic endosymbionts, providing hosts with macromolecular precursors and vitamins. Here we discuss the two independent origins of endosymbiosis within trypanosomatids and subsequently different evolutionary trajectories that see entrainment vs tolerance of symbiont cell divisions cycles within those of the host. With the potential to inform on the transition to obligate parasitism in the trypanosomatids, interest in the biology and ecology of free-living, phagotrophic kinetoplastids is beginning to enjoy a renaissance. Thus, we take the opportunity to additionally consider the wider relevance of endosymbiosis during kinetoplastid evolution, including the indulged lifestyle and reductive evolution of basal kinetoplastid Perkinsela.

• MeSH
• biodiverzita MeSH
• biologická evoluce * MeSH
• genom protozoální MeSH
• Kinetoplastida genetika   MeSH
• Leishmania genetika   fyziologie   MeSH
• molekulární evoluce MeSH
• symbióza * MeSH
• Trypanosoma genetika   fyziologie   MeSH
• Trypanosomatina genetika   MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• přehledy MeSH

Pathogens possess the ability to adapt and survive in some host species but not in others-an ecological trait known as host tropism. Transmitted through ticks and carried mainly by mammals and birds, the Lyme disease (LD) bacterium is a well-suited model to study such tropism. Three main causative agents of LD, Borrelia burgdorferi, B. afzelii, and B. garinii, vary in host ranges through mechanisms eluding characterization. By feeding ticks infected with different Borrelia species, utilizing feeding chambers and live mice and quail, we found species-level differences in bacterial transmission. These differences localize on the tick blood meal, and specifically complement, a defense in vertebrate blood, and a polymorphic bacterial protein, CspA, which inactivates complement by binding to a host complement inhibitor, Factor H (FH). CspA selectively confers bacterial transmission to vertebrates that produce FH capable of allele-specific recognition. CspA is the only member of the Pfam54 gene family to exhibit host-specific FH-binding. Phylogenetic analyses revealed convergent evolution as the driver of such uniqueness, and that FH-binding likely emerged during the last glacial maximum. Our results identify a determinant of host tropism in Lyme disease infection, thus defining an evolutionary mechanism that shapes host-pathogen associations.

• MeSH
• bakteriální proteiny genetika   metabolismus   MeSH
• biologická evoluce MeSH
• Borrelia burgdorferi genetika   růst a vývoj   imunologie   MeSH
• druhová specificita MeSH
• imunitní únik fyziologie   MeSH
• interakce hostitele a patogenu fyziologie   MeSH
• klíšťata MeSH
• komplement - faktor H metabolismus   MeSH
• křepelky a křepelovití MeSH
• lidé MeSH
• lymeská nemoc imunologie   přenos   MeSH
• myši MeSH
• tropismus virů fyziologie   MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Research Support, N.I.H., Extramural MeSH
• Research Support, U.S. Gov't, Non-P.H.S. MeSH

• MeSH
• biologická evoluce MeSH
• viry MeSH
• Publikační typ
• sborníky MeSH

• Konspekt
• Virologie
• NLK Obory
• virologie
• biologie

• MeSH
• Anaplasma phagocytophilum MeSH
• biologická adaptace genetika   fyziologie   MeSH
• biologická evoluce MeSH
• ekologie * MeSH
• genetická transkripce genetika   MeSH
• interakce hostitele a patogenu genetika   MeSH
• klíšťata mikrobiologie   MeSH
• klíště mikrobiologie   MeSH
• molekulární evoluce MeSH
• regulace genové exprese genetika   MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH