Coevolution
Dotaz
Zobrazit nápovědu
Coevolution between bacteria and bacteriophages can be characterized as an infinitive constant evolutionary battle (phage-host arm race), which starts during phage adsorption and penetration into host cell, continues during phage replication inside the cells, and remains preserved also during prophage lysogeny. Bacteriophage may exist inside the bacterial cells in four forms with different evolutionary strategies: as a replicating virus during the lytic cycle, in an unstable carrier state termed pseudolysogeny, as a prophage with complete genome during the lysogeny, or as a defective cryptic prophage. Some defensive mechanisms of bacteria and virus countermeasures are characterized, and some evolutionary questions concerning phage-host relationship are discussed.
The importance of gene expression regulation in viruses based upon G-quadruplex may point to its potential utilization in therapeutic targeting. Here, we present analyses as to the occurrence of putative G-quadruplex-forming sequences (PQS) in all reference viral dsDNA genomes and evaluate their dependence on PQS occurrence in host organisms using the G4Hunter tool. PQS frequencies differ across host taxa without regard to GC content. The overlay of PQS with annotated regions reveals the localization of PQS in specific regions. While abundance in some, such as repeat regions, is shared by all groups, others are unique. There is abundance within introns of Eukaryota-infecting viruses, but depletion of PQS in introns of bacteria-infecting viruses. We reveal a significant positive correlation between PQS frequencies in dsDNA viruses and corresponding hosts from archaea, bacteria, and eukaryotes. A strong relationship between PQS in a virus and its host indicates their close coevolution and evolutionarily reciprocal mimicking of genome organization.
Two house mouse subspecies occur in Europe, eastern and northern Mus musculus musculus (Mmm) and western and southern Mus musculus domesticus (Mmd). A secondary hybrid zone occurs where their ranges meet, running from Scandinavia to the Black Sea. In this paper, we tested a hypothesis that the apicomplexan protozoan species Cryptosporidium tyzzeri has coevolved with the house mouse. More specifically, we assessed to what extent the evolution of this parasite mirrors divergence of the two subspecies. In order to test this hypothesis, we analysed sequence variation at five genes (ssrRNA, Cryptosporidium oocyst wall protein (COWP), thrombospondin-related adhesive protein of Cryptosporidium 1 (TRAP-C1), actin and gp60) in C. tyzzeri isolates from Mmd and Mmm sampled along a transect across the hybrid zone from the Czech Republic to Germany. Mmd samples were supplemented with mice from New Zealand. We found two distinct isolates of C. tyzzeri, each occurring exclusively in one of the mouse subspecies (C. tyzzeri-Mmm and C. tyzzeri-Mmd). In addition to genetic differentiation, oocysts of the C. tyzzeri-Mmd subtype (mean: 4.24×3.69μm) were significantly smaller than oocysts of C. tyzzeri-Mmm (mean: 4.49×3.90 μm). Mmm and Mmd were susceptible to experimental infection with both C. tyzzeri subtypes; however, the subtypes were not infective for the rodent species Meriones unguiculatus, Mastomys coucha, Apodemus flavicollis or Cavia porcellus. Overall, our results support the hypothesis that C. tyzzeri is coevolving with Mmm and Mmd.
- MeSH
- biologická evoluce * MeSH
- Cryptosporidium klasifikace genetika izolace a purifikace MeSH
- fylogeneze MeSH
- genetická variace MeSH
- genotyp MeSH
- kryptosporidióza veterinární MeSH
- molekulární sekvence - údaje MeSH
- myši MeSH
- nemoci hlodavců parazitologie MeSH
- protozoální proteiny genetika MeSH
- RNA ribozomální 18S genetika MeSH
- sekvenční analýza DNA MeSH
- shluková analýza MeSH
- zvířata MeSH
- Check Tag
- myši MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Research Support, N.I.H., Extramural MeSH
- Geografické názvy
- Česká republika MeSH
- Německo MeSH
BACKGROUND: Co-evolutionary arms-races result in spatio-temporally dynamic relationships between interacting species, e.g., brood parasites and their avian hosts. However, majority of avian co-evolutionary studies are limited to "snap-shots" of a single breeding season in an open-nesting host. In a long-term study (11 breeding seasons), we explored a unique system between the brood parasitic common cuckoo (Cuculus canorus) and its host, the common redstart (Phoenicurus phoenicurus) which is exceptional among all cuckoo hosts due to being a cavity nester. Conditions in cavities are different from open nests, e.g., lower risks of predation, more favourable microclimate, increased risks of unsuccessful eviction of host offspring by the cuckoo nestling. Different conditions in cavities thus can be expected to shape parasite-host coevolution differently from what is typically studied in open nesting hosts. RESULTS: In our highly parasitised nest-box population (32.5%, n = 569 nests) only 35.7% of cuckoo eggs were laid into the nest cup and incubated by redstarts. Host nests shifted availability to later into the breeding season from 2006 to 2016 and cuckoos followed this trend by also shifting their timing of parasitism. Although previous studies revealed that redstarts selectively eject experimental non-mimetic eggs (desertion was not a specific response to foreign eggs), the hosts never ejected naturally-laid cuckoo eggs or cuckoo eggs cross-fostered into naturally non-parasitised nests. We solve the long-standing debate about the origin of cuckoo eggs found on the nest rim: we gained the first direct video-recording evidence that eggs found on the nest rim were mislaid by parasites and not ejected by hosts. Naturally-parasitised nests were deserted more often (18.6%) than control non-parasitized nests (5.6%) or nests artificially parasitised by us (1.4%). This suggests that the sight of the laying cuckoo female is the primary cue that triggers egg rejection (by desertion) in this host. Review of data from this and other study sites (10 populations, n = 853 experiments) demonstrates high variability in rejection rates and shows that populations facing higher parasitism rates reject parasitic eggs with higher frequencies. Surprisingly, cuckoo chicks either growing solitarily or with redstart chicks did not differ in their fledging success. CONCLUSIONS: We suggest that the redstart is an ideal model system to study the flexibility and limits of brood parasite-host co-evolution in an extreme ecological setting.
- MeSH
- biologická evoluce * MeSH
- biologické modely * MeSH
- ekologie * MeSH
- hnízdění fyziologie MeSH
- kladení vajíček fyziologie MeSH
- ovum fyziologie MeSH
- paraziti fyziologie MeSH
- Passeriformes fyziologie MeSH
- ptáci fyziologie MeSH
- roční období MeSH
- zeměpis MeSH
- zvířata MeSH
- Check Tag
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- Geografické názvy
- Finsko MeSH
257 s. : il.
The range of hosts exploited by a parasite is determined by several factors, including host availability, infectivity and exploitability. Each of these can be the target of natural selection on both host and parasite, which will determine the local outcome of interactions, and potentially lead to coevolution. However, geographical variation in host use and specificity has rarely been investigated. Maculinea (= Phengaris) butterflies are brood parasites of Myrmica ants that are patchily distributed across the Palæarctic and have been studied extensively in Europe. Here, we review the published records of ant host use by the European Maculinea species, as well as providing new host ant records for more than 100 sites across Europe. This comprehensive survey demonstrates that while all but one of the Myrmica species found on Maculinea sites have been recorded as hosts, the most common is often disproportionately highly exploited. Host sharing and host switching are both relatively common, but there is evidence of specialization at many sites, which varies among Maculinea species. We show that most Maculinea display the features expected for coevolution to occur in a geographic mosaic, which has probably allowed these rare butterflies to persist in Europe. This article is part of the theme issue 'The coevolutionary biology of brood parasitism: from mechanism to pattern'.
- MeSH
- druhová specificita MeSH
- Formicidae parazitologie MeSH
- hnízdění * MeSH
- interakce hostitele a parazita * MeSH
- koevoluce * MeSH
- motýli fyziologie MeSH
- symbióza * MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Geografické názvy
- Evropa MeSH
Some of the species from the genus Neoparamoeba, for example N. perurans have been shown to be pathogenic to aquatic animals and thus have economic significance. They all contain endosymbiont, Perkinsela amoebae like organisms (PLOs). In this study we investigated phylogenetic ambiguities within the Neoparamoeba taxonomy and phylogenetic congruence between PLOs and their host Neoparamoeba to confirm the existence of a single ancient infection/colonisation that led to cospeciation between all PLOs and their host Neoparamoeba. DNA was extracted and rRNA genes from host amoeba and endosymbiont were amplified using PCR. Uncertainties in the Neoparamoeba phylogeny were initially resolved by a secondary phylogenetic marker, the internal transcribed spacer 2 (ITS2). The secondary structure of ITS2 was reconstructed for Neoparamoeba. The ITS2 was phylogenetically informative, separating N. pemaquidensis and N. aestuarina into distinct monophyletic clades and designating N. perurans as the most phylogenetically divergent Neoparamoeba species. The new phylogenetic data were used to verify the tree topologies used in cophylogenetic analyses that revealed strict phylogenetic congruence between endosymbiotic PLOs with their host Neoparamoeba. Strict congruence in the phylogeny of all PLOs and their host Neoparamoeba was demonstrated implying that PLOs are transmitted vertically from parent to daughter cell.
- MeSH
- Amoebozoa genetika parazitologie MeSH
- fylogeneze * MeSH
- Kinetoplastida klasifikace genetika fyziologie MeSH
- mezerníky ribozomální DNA genetika MeSH
- molekulární sekvence - údaje MeSH
- RNA ribozomální 18S genetika MeSH
- symbióza * MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
The entodiniomorphid ciliate Troglodytella abrassarti is a colonic mutualist of great apes. Its host specificity makes it a suitable model for studies of primate evolution. We explored molecular diversity of T. abrassarti with regard to large geographical distribution and taxonomic diversity of its most common host, the chimpanzee. We found a very low diversification of T. abrassarti in chimpanzees across Africa. Distribution of two types of T. abrassarti supports evolutionary separation of the Western chimpanzee, P. t. verus, from populations in Central and East Africa. Type I T. abrassarti is probably a derived form, which corresponds with the Central African origin of chimpanzees and a founder event leading to P. t. verus. Exclusivity of the respective types of T. abrassarti to Western and Central/Eastern chimpanzees corroborates the difference found between an introduced population of presumed Western chimpanzees on Rubondo Island and an autochthonous population in mainland Tanzania. The identity of T. abrassarti from Nigerian P. t. ellioti and Central African chimpanzees suggests their close evolutionary relationship. Although this contrasts with published mtDNA data, it corroborates current opinion on the exclusive position of P. t. verus within the chimpanzee phylogeny. The type of T. abrassarti occurring in Central and East African common chimpanzee was confirmed also in bonobos. This may point to the presence of an ancestral Type II found throughout the Lower Guinean rainforest dating back to the common Pan ancestor. Alternatively, the molecular uniformity of T. abrassarti may imply a historical overlap of the species' distribution ranges.
- MeSH
- Ciliophora genetika MeSH
- druhová specificita MeSH
- feces parazitologie MeSH
- fylogeneze MeSH
- genetická variace MeSH
- infekce prvoky kmene Ciliophora genetika parazitologie veterinární MeSH
- molekulární evoluce MeSH
- Pan troglodytes genetika parazitologie MeSH
- polymerázová řetězová reakce MeSH
- protozoální DNA analýza MeSH
- sekvenční analýza DNA MeSH
- shluková analýza MeSH
- symbióza genetika MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Geografické názvy
- subsaharská Afrika MeSH
Larger species tend to feed on abundant resources, which nonetheless have lower quality or degradability, the so-called Jarman-Bell principle. The "eat more" hypothesis posits that larger animals compensate for lower quality diets through higher consumption rates. If so, evolutionary shifts in metabolic scaling should affect the scope for this compensation, but whether this has happened is unknown. Here, we investigated this issue using termites, major tropical detritivores that feed along a humification gradient ranging from dead plant tissue to mineral soil. Metabolic scaling is shallower in termites with pounding mandibles adapted to soil-like substrates than in termites with grinding mandibles adapted to fibrous plant tissue. Accordingly, we predicted that only larger species of the former group should have more humified, lower quality diets, given their higher scope to compensate for such a diet. Using literature data on 65 termite species, we show that diet humification does increase with body size in termites with pounding mandibles, but is weakly related to size in termites with grinding mandibles. Our findings suggest that evolution of metabolic scaling may shape the strength of the Jarman-Bell principle.
- MeSH
- biologická evoluce * MeSH
- dieta * MeSH
- Isoptera genetika metabolismus MeSH
- mandibula MeSH
- velikost těla * MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
