Host Dotaz Zobrazit nápovědu
- MeSH
- lidé MeSH
- nemoc štěpu proti hostiteli diagnóza etiologie terapie MeSH
- potransfuzní reakce * MeSH
- reakce štěpu proti hostiteli * MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- přehledy MeSH
Recent studies show that host switching is much more frequent than originally believed and constitutes an important driver in evolution of host-parasite associations. However, its frequency and ecological mechanisms at the population level have been rarely investigated. We address this issue by analyzing phylogeny and population genetics of an extensive sample, from a broad geographic area, for commonly occurring parasites of the genus Eimeria within the abundant rodent genera Apodemus, Microtus and Myodes, using two molecular markers. At the most basal level, we demonstrate polyphyletic arrangement, i.e. multiple origin, of the rodent-specific clusters within the Eimeria phylogeny, and strong genetic/phylogenetic structure within these lineages determined at least partially by specificities to different host groups. However, a novel and the most important observation is a repeated occurrence of host switches among closely related genetic lineages which may become rapidly fixed. Within the studied model, this phenomenon applies particularly to the switches between the eimerians from Apodemus flavicollis/Apodemus sylvaticus and Apodemus agrarius groups. We show that genetic differentiation and isolation between A. flavicollis/A. sylvaticus and A. agrarius faunas is a secondary recent event and does not reflect host-parasite coevolutionary history. Rather, it provides an example of rapid ecology-based differentiation in the parasite population.
- Klíčová slova
- Coevolution, Ecological fitting, Host specificity, Host switching, Parasite, Rodent,
- MeSH
- biodiverzita * MeSH
- časové faktory MeSH
- Coccidia klasifikace genetika fyziologie MeSH
- fylogeneze MeSH
- haplotypy genetika MeSH
- hostitelská specificita * MeSH
- interakce hostitele a parazita * genetika MeSH
- Murinae parazitologie MeSH
- populační genetika MeSH
- zeměpis MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Generalist parasites have the capacity to infect multiple hosts. The temporal pattern of host specificity by generalist parasites is rarely studied, but is critical to understanding what variables underpin infection and thereby the impact of parasites on host species and the way they impose selection on hosts. Here, the temporal dynamics of infection of four species of freshwater mussel by European bitterling fish (Rhodeus amarus) was investigated over three spawning seasons. Bitterling lay their eggs in the gills of freshwater mussels, which suffer reduced growth, oxygen stress, gill damage and elevated mortality as a result of parasitism. The temporal pattern of infection of mussels by European bitterling in multiple populations was examined. Using a Bernoulli Generalized Additive Mixed Model with Bayesian inference it was demonstrated that one mussel species, Unio pictorum, was exploited over the entire bitterling spawning season. As the season progressed, bitterling showed a preference for other mussel species, which were inferior hosts. Temporal changes in host use reflected elevated density-dependent mortality in preferred hosts that were already infected. Plasticity in host specificity by bitterling conformed with the predictions of the host selection hypothesis. The relationship between bitterling and their host mussels differs qualitatively from that of avian brood parasites.
- Klíčová slova
- Brood parasite, Host–parasite co-evolution, Oviposition, Spawning site, Superparasitism,
- MeSH
- Bayesova věta MeSH
- Cyprinidae MeSH
- hostitelská specificita * MeSH
- interakce hostitele a parazita * MeSH
- paraziti MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Mastomys natalensis-borne mammarenaviruses appear specific to subspecific M. natalensis taxa rather than to the whole species. Yet mammarenaviruses carried by M. natalensis are known to spill over and jump hosts in northern sub-Saharan Africa. Phylogeographic studies increasingly show that, like M. natalensis, small mammals in sub-Saharan Africa are often genetically structured into several subspecific taxa. Other mammarenaviruses may thus also form virus-subspecific host taxon associations. To investigate this, and if mammarenaviruses carried by M. natalensis in southern Africa are less prone to spill-over, we screened 1225 non-M. natalensis samples from Tanzania where many small mammal taxa meet. We found mammarenavirus RNA in 6 samples. Genetic/genomic characterisation confirmed they were not spill-over from M. natalensis. We detected host jumps among rodent tribe members and an association between mammarenaviruses and subspecific taxa of Mus minutoides and Grammomys surdaster, indicating host genetic structure may be crucial to understand virus distribution and host specificity.
- Klíčová slova
- Berega virus, Comparative phylogeography, Grammomys surdaster, Host genetic structure, Host jump, Host specificity, Mus minutoides, Ngerengere virus, Songea virus, Spill-over,
- MeSH
- Arenaviridae * genetika MeSH
- fylogeografie MeSH
- hostitelská specificita MeSH
- Murinae MeSH
- nemoci hlodavců * MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Geografické názvy
- Tanzanie MeSH
Monogenea (Platyhelminthes), mainly gill and fin ectoparasites of fish, are often recognized as host specific and morphologically and ecologically diverse. These parasites exhibit high species diversity at the level of host species or individual fish specimens. Using case studies, especially those widely performed in Dactylogyrus parasitizing cyprinoid fish, this article presents current knowledge on the ecology and evolution of congeneric gill monogeneans. The important aspects of the ecology of congeneric monogeneans are highlighted, in particular: host specificity expressed at several host levels (from strict specificity to phylogenetic specificity), microhabitat specificity expressed by restricted positions on fish gills to facilitate intraspecific mating, and the link between microhabitat preference and morphological adaptation (i.e., sclerotized structures of the haptor) or reproductive isolation. From the evolutionary perspective, this study focused on the processes of the speciation and diversification of congeneric monogeneans, highlighting the role of host switch as the most prominent coevolutionary event, accompanied in some cases mostly by intrahost speciation or cospeciation, as revealed by cophylogenetic studies. Here, important knowledge on evolutionary patterns of host specificity, microhabitat specificity, and morphological adaptation is presented. Host-specific monogeneans may represent an important tool for studying the historical biogeography of their hosts. Specifically, in the case of freshwater fish hosts exhibiting disjunctive distribution, they reflect both historical and contemporary contacts. The role of host-specific congeneric monogeneans in revealing historical intercontinental and intracontinental contacts between freshwater fish is highlighted. Finally, the importance of the role of genetic coadaptation, limiting the presence of host-specific monogeneans in hybrid fish, is emphasized.
TITLE: Monogènes spécifiques à leur hôte parasitant les poissons d’eau douce : écologie et évolution des associations hôtes-parasites. ABSTRACT: Les Monogènes (Plathelminthes), principalement ectoparasites des branchies et des nageoires des poissons, sont souvent reconnus comme spécifiques à leur hôte et diversifiés morphologiquement et écologiquement. Ces parasites présentent une grande diversité d’espèces au niveau des espèces hôtes ou des spécimens individuels de poissons. À l’aide d’études de cas (en particulier celles largement réalisées chez les Dactylogyrus parasitant les poissons cyprinoïdes), les connaissances actuelles sur l’écologie et l’évolution des monogènes branchiaux congénères sont présentées. Les aspects importants de l’écologie des monogènes congénères sont mis en évidence, en particulier la spécificité à l’hôte exprimée à plusieurs niveaux de l’hôte (de la spécificité stricte à la spécificité phylogénétique), la spécificité du microhabitat exprimée par des positions restreintes sur les branchies des poissons pour faciliter l’accouplement intraspécifique, et le lien entre la préférence du microhabitat et l’adaptation morphologique (c’est-à-dire les structures sclérifiées du hapteur) ou l’isolement reproductif. Du point de vue évolutif, l’étude a été concentrée sur les processus de spéciation et de diversification des monogènes congénères, soulignant le rôle du changement d’hôte comme l’événement coévolutif le plus important, accompagné surtout dans certains cas de spéciation ou de cospéciation intra-hôte, comme le révèlent les études cophylogénétiques. Des connaissances importantes sont présentées ici sur les modèles évolutifs de spécificité d’hôte, de spécificité de microhabitat et d’adaptation morphologique. Les monogènes spécifiques à l’hôte peuvent représenter un outil important pour étudier la biogéographie historique de leurs hôtes. Plus précisément, dans le cas des poissons d’eau douce hôtes présentant une distribution disjonctive, ils reflètent à la fois des contacts historiques et contemporains. Le rôle des monogènes congénères spécifiques à leur hôte dans la révélation des contacts intercontinentaux et intracontinentaux historiques entre poissons d’eau douce est mis en évidence. Enfin, l’importance du rôle de la coadaptation génétique limitant la présence de monogènes spécifiques à l’hôte chez les poissons hybrides est soulignée.
- Klíčová slova
- Fish parasites, Genetic coadaptation, Host specificity, Host-parasite coevolution, Monogeneans, Species coexistence,
- MeSH
- biologická evoluce * MeSH
- druhová specificita MeSH
- ekosystém MeSH
- fylogeneze MeSH
- hostitelská specificita * MeSH
- infekce červy třídy Trematoda veterinární parazitologie MeSH
- interakce hostitele a parazita * MeSH
- nemoci ryb * parazitologie MeSH
- ploštěnci fyziologie klasifikace genetika izolace a purifikace MeSH
- ryby parazitologie MeSH
- sladká voda * parazitologie MeSH
- Trematoda fyziologie klasifikace genetika MeSH
- žábry * parazitologie MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- přehledy MeSH
Host-parasite dynamics involve coevolutionary arms races, which may lead to host specialization and ensuing diversification. Our general understanding of the evolution of host specialization in brood parasites is compromised by a restricted focus on bird and insect lineages. The cuckoo catfish (Synodontis multipunctatus) is an obligate parasite of parental care of mouthbrooding cichlids in Lake Tanganyika. Given the ecological and taxonomic diversity of mouthbrooding cichlids in the lake, we hypothesized the existence of sympatric host-specific lineages in the cuckoo catfish. In a sample of 779 broods from 20 cichlid species, we found four species parasitized by cuckoo catfish (with prevalence of parasitism of 2%-18%). All parasitized cichlids were from the tribe Tropheini, maternal mouthbrooders that spawn over a substrate (rather than in open water). Phylogenetic analysis based on genomic (ddRAD sequencing) and mitochondrial (Dloop) data from cuckoo catfish embryos showed an absence of host-specific lineages. This was corroborated by analyses of genetic structure and co-ancestry matrix. Within host species, parasitism was not associated with any individual characteristic we recorded (parent size, water depth), but was costly as parasitized parents carried smaller clutches of their own offspring. We conclude that the cuckoo catfish is an intermediate generalist and discuss costs, benefits and constraints of host specialization in this species and brood parasites in general.
- Klíčová slova
- brood parasitism, fish, host specialisation, host-parasite relationship, interspecific interactions, social evolution,
- MeSH
- cichlidy * genetika MeSH
- fylogeneze MeSH
- hnízdění MeSH
- interakce hostitele a parazita genetika MeSH
- paraziti * MeSH
- sumci * genetika MeSH
- voda MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Názvy látek
- voda MeSH
The host-pathogen interaction represents a complex and dynamic biological system. The outcome of this interaction is dependent on the microbial pathogen properties to establish infection and the ability of the host to control infection. Although bacterial pathogens have evolved a variety of strategies to subvert host defense functions, several general mechanisms have been shown to be shared among these pathogens. As a result, host effectors that are critical for pathogen entry, survival and replication inside the host cells have become a new paradigm for antimicrobial targeting. This review focuses on the potential utility of a proteomics approach in defining the host-pathogen interaction from the host's perspective.
- MeSH
- bakteriální infekce imunologie metabolismus MeSH
- interakce hostitele a patogenu * MeSH
- lidé MeSH
- proteiny analýza MeSH
- proteom imunologie metabolismus MeSH
- proteomika metody MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- přehledy MeSH
- Názvy látek
- proteiny MeSH
- proteom MeSH
Analytical methods can offer insights into the structure of biological networks, but mechanisms that determine the structure of these networks remain unclear. We conducted a synthesis based on 111 previously published datasets to assess a range of ecological and evolutionary mechanisms that may influence the plant-associated fungal interaction networks. We calculated the relative host effect on fungal community composition and compared nestedness and modularity among different mycorrhizal types and endophytic fungal guilds. We also assessed how plant-fungal network structure was related to host phylogeny, environmental and sampling properties. Orchid mycorrhizal fungal communities responded most strongly to host identity, but the effect of host was similar among all other fungal guilds. Community nestedness, which did not differ among fungal guilds, declined significantly with increasing mean annual precipitation on a global scale. Orchid and ericoid mycorrhizal fungal communities were more modular than ectomycorrhizal and root endophytic communities, with arbuscular mycorrhizal fungi in an intermediate position. Network properties among a broad suite of plant-associated fungi were largely comparable and generally unrelated to phylogenetic distance among hosts. Instead, network metrics were predominantly affected by sampling and matrix properties, indicating the importance of study design in properly inferring ecological patterns.
- Klíčová slova
- endophytes, host specificity, macroecology, modularity, mycorrhizal fungi, nestedness, network analysis, phylogenetic distance,
- MeSH
- déšť MeSH
- hostitelská specificita MeSH
- houby fyziologie MeSH
- interakce hostitele a patogenu fyziologie MeSH
- rostliny mikrobiologie MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Systems biology approaches, especially in the big data era, have revolutionized modern parasitology. Of the many different molecules participating in parasite-host interactions, noncoding RNAs (ncRNAs) are now known to be (i) transmitted by the vector to possibly modulate vertebrate host responses and favor vector survival and (ii) regulated in the host by parasites to favor parasite survival. Here we provide an overview of the involvement of ncRNAs in the parasite-vector-host triad and their effect on host homeostasis based on recent advances and accumulating knowledge about the role of endogenous vertebrate noncoding RNAs in vertebrate host physiology.
- Klíčová slova
- arthropod vectors, epigenetics, miRNA, noncoding RNA, parasite–vertebrate–host interaction, pathogenesis,
- MeSH
- homeostáza fyziologie MeSH
- infekce přenášené vektorem * MeSH
- interakce hostitele a parazita genetika imunologie MeSH
- lidé MeSH
- nekódující RNA genetika imunologie MeSH
- obratlovci imunologie parazitologie MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- přehledy MeSH
- Názvy látek
- nekódující RNA MeSH
Parasitic helminths are destined to share niches with a variety of microbiota that inevitably influence their interaction with the host. To modulate the microbiome for their benefit and defend against pathogenic isolates, helminths have developed host defense peptides (HDPs) and proteins as integral elements of their immunity. These often exert a relatively nonspecific membranolytic activity toward bacteria, sometimes with limited or no toxicity toward host cells. With a few exceptions, such as nematode cecropin-like peptides and antibacterial factors (ABFs), helminthic HDPs are largely underexplored. This review scrutinizes current knowledge on the repertoire of such peptides in helminths and promotes their research as potential leads for an anti-infective solution to the burgeoning problem of antibiotic resistance.
- Klíčová slova
- antimicrobial peptides, helminths, host defense peptides, immunity, microbiome,
- MeSH
- Bacteria MeSH
- cizopasní červi * MeSH
- kationické antimikrobiální peptidy MeSH
- paraziti * MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- přehledy MeSH
- Názvy látek
- kationické antimikrobiální peptidy MeSH