Nejvíce citovaný článek - PubMed ID 17021158
Discovering how species' thermal limits evolve and vary spatially is crucial for predicting their vulnerability to ongoing environmental warming. Current evidence indicates that heat tolerance is less spatially variable than cold tolerance among species, presenting a major concern for organismal vulnerability in a rapidly warming world. This asymmetry in thermal limits has been supported by large-scale geographic studies, across latitudinal and elevational gradients (known as Brett's heat-invariant rule). Yet, how critical limits vary across finer spatial scales (e.g., across microenvironments) is less understood. Here, we show that minimum temperatures are more variable than maximum temperatures at large geographic scales (across latitude/elevation) but are less variable at local scales (within sites), in turn guiding spatial asymmetries in thermal tolerances. Using thermal tolerance measurements from amphibians, insects, and reptiles, we confirm the invariance of heat tolerance at large spatial scales and also find more variable heat than cold tolerances at local scales (an inverted Brett's heat-invariant rule at fine spatial scales). Our results suggest that regional- or global-level studies will likely obscure fine-scale structuring in thermal habitats and corresponding patterns of local heat tolerance adaptation. We emphasize that inferences based on broadscale geographic patterns obscure fine-scale variation in thermal physiology. For instance, a genetic basis for fine-scale variation in thermal physiology may reshuffle spatial and phylogenetic patterns of vulnerability.
- Klíčová slova
- Brett's heat‐invariant rule, elevation, latitude, local scale, macrophysiology, microclimate, spatial scales, amphibians, reptiles, insects, thermal tolerance limits,
- MeSH
- biologické modely MeSH
- ekosystém MeSH
- hmyz * fyziologie MeSH
- obojživelníci * fyziologie MeSH
- plazi * fyziologie MeSH
- vysoká teplota * MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
BACKGROUND: Booklice (psocids) in the genus Liposcelis (Psocoptera: Liposcelididae) are a group of important storage pests, found in libraries, grain storages, and food-processing facilities. Booklice are able to survive under heat treatment and typically possess high resistance to common fumigant insecticides, hence posing a threat to storage security worldwide. RESULTS: We assembled the genome of the booklouse, L. brunnea, the first genome reported in Psocoptera, using PacBio long-read sequencing, Illumina sequencing, and chromatin conformation capture (Hi-C) methods. After assembly, polishing, haplotype purging, and Hi-C scaffolding, we obtained 9 linkage groups (174.1 Mb in total) ranging from 12.1 Mb to 27.6 Mb (N50: 19.7 Mb), with the BUSCO completeness at 98.9%. In total, 15,543 genes were predicted by the Maker pipeline. Gene family analyses indicated the sensing-related gene families (OBP and OR) and the resistance-related gene families (ABC, EST, GST, UGT, and P450) expanded significantly in L. brunnea compared with those of their closest relatives (2 parasitic lice). Based on transcriptomic analysis, we found that the CYP4 subfamily from the P450 gene family functioned during phosphine fumigation; HSP genes, particularly those from the HSP70 subfamily, were upregulated significantly under high temperatures. CONCLUSIONS: We present a chromosome-level genome assembly of L. brunnea, the first genome reported for the order Psocoptera. Our analyses provide new insights into the gene family evolution of the louse clade and the transcriptomic responses of booklice to environmental stresses.
- Klíčová slova
- Liposcelis brunnea, booklice, genome assembly, high temperature tolerance, insecticide resistance, louse evolution,
- MeSH
- chromozomy MeSH
- genom mitochondriální * MeSH
- hmyz genetika MeSH
- Phthiraptera * genetika MeSH
- sekvenční analýza DNA MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Scaling evolutionary trees to time is essential for understanding the origins of clades. Recently developed methods allow including the entire fossil record known for the group of interest and eliminated the need for specifying prior distributions for node ages. Here we apply the fossilized birth-death (FBD) approach to reconstruct the diversification timeline of the viperines (subfamily Viperinae). Viperinae are an Old World snake subfamily comprising 102 species from 13 genera. The fossil record of vipers is fairly rich and well assignable to clades due to the unique vertebral and fang morphology. We use an unprecedented sampling of 83 modern species and 13 genetic markers in combination with 197 fossils representing 28 extinct taxa to reconstruct a time-calibrated phylogeny of the Viperinae. Our results suggest a late Eocene-early Oligocene origin with several diversification events following soon after the group's establishment. The age estimates inferred with the FBD model correspond to those from previous studies that were based on node dating but FBD provides notably narrower credible intervals around the node ages. Viperines comprise two African and an Eurasian clade, but the ancestral origin of the subfamily is ambiguous. The most parsimonious scenarios require two transoceanic dispersals over the Tethys Sea during the Oligocene.
- MeSH
- biologická evoluce MeSH
- biologické modely MeSH
- fylogeneze MeSH
- genetické markery * MeSH
- sekvenční analýza DNA MeSH
- Viperidae klasifikace genetika MeSH
- výpočetní biologie metody MeSH
- zkameněliny MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Názvy látek
- genetické markery * MeSH
The mechanisms of response to radiation exposure are conserved in plants and animals. The DNA damage response (DDR) pathways are the predominant molecular pathways activated upon exposure to radiation, both in plants and animals. The conserved features of DDR in plants and animals might facilitate interdisciplinary studies that cross traditional boundaries between animal and plant biology in order to expand the collection of biomarkers currently used for radiation exposure monitoring (REM) in environmental and biomedical settings. Genes implicated in trans-kingdom conserved DDR networks often triggered by ionizing radiation (IR) and UV light are deposited into biological databases. In this study, we have applied an innovative approach utilizing data pertinent to plant and human genes from publicly available databases towards the design of a 'plant radiation biodosimeter', that is, a plant and DDR gene-based platform that could serve as a REM reliable biomarker for assessing environmental radiation exposure and associated risk. From our analysis, in addition to REM biomarkers, a significant number of genes, both in human and Arabidopsis thaliana, not yet characterized as DDR, are suggested as possible DNA repair players. Last but not least, we provide an example on the applicability of an Arabidopsis thaliana-based plant system monitoring the role of cancer-related DNA repair genes BRCA1, BARD1 and PARP1 in processing DNA lesions.
- Klíčová slova
- DNA damage repair, bioinformatics, in silico analysis, ionizing radiation, plant radiation biodosimeter, ultraviolet radiation,
- Publikační typ
- časopisecké články MeSH
Retroviruses can create endogenous forms on infiltration into the germline cells of their hosts. These forms are then vertically transmitted and can be considered as genetic fossils of ancient viruses. All retrovirus genera, with the exception of deltaretroviruses, have had their representation identified in the host genome as a virus fossil record. Here we describe an endogenous Deltaretrovirus, identified in the germline of long-fingered bats (Miniopteridae). A single, heavily deleted copy of this retrovirus has been found in the genome of miniopterid species, but not in the genomes of the phylogenetically closest bat families, Vespertilionidae and Cistugonidae. Therefore, the endogenization occurred in a time interval between 20 and 45 million years ago. This discovery closes the last major gap in the retroviral fossil record and provides important insights into the history of deltaretroviruses in mammals.
- Klíčová slova
- Chiroptera, Deltaretroviruses, endogenous retroviruses,
- MeSH
- Chiroptera klasifikace genetika MeSH
- Deltaretrovirus genetika MeSH
- endogenní retroviry genetika MeSH
- fylogeneze MeSH
- genom * MeSH
- genomika metody MeSH
- konformace nukleové kyseliny MeSH
- konsenzuální sekvence MeSH
- molekulární evoluce MeSH
- otevřené čtecí rámce MeSH
- sekvence nukleotidů MeSH
- virové geny MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
The centromere drive model explaining rapid evolution of eukaryotic centromeres predicts higher frequency of positive selection acting on centromeric histone H3 (CenH3) in clades with asymmetric meiosis compared to the clades with only symmetric meiosis. However, despite the impression one might get from the literature, this key prediction of the centromere drive model has not only never been confirmed, but it has never been tested, because all the previous studies dealt only with the presence or absence instead of the frequency of positive selection. To provide evidence for or against different frequencies of positively selected CenH3 in asymmetrics and symmetrics, we have inferred the selective pressures acting on CenH3 in seventeen eukaryotic clades, including plants, animals, fungi, ciliates and apicomplexa, using codon-substitution models, and compared the inferred frequencies between asymmetrics and symmetrics in a quantitative manner. We have found that CenH3 has been evolving adaptively much more frequently in clades with asymmetric meiosis compared with clades displaying only symmetric meiosis which confirms the prediction of centromere drive model. Our findings indicate that the evolution of asymmetric meiosis required CenH3 to evolve adaptively more often to counterbalance the negative consequences of centromere drive.
- MeSH
- centromera genetika MeSH
- histony genetika MeSH
- houby genetika MeSH
- kodon genetika MeSH
- lidé MeSH
- meióza genetika MeSH
- molekulární evoluce * MeSH
- protein CENP-A genetika MeSH
- rostlinné proteiny genetika MeSH
- sekvenční seřazení MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Názvy látek
- CENPA protein, human MeSH Prohlížeč
- histony MeSH
- kodon MeSH
- protein CENP-A MeSH
- rostlinné proteiny MeSH
Hybridization between distinct species of animals and subsequent genetic introgression plays a considerable role in the speciation process and the emergence of adaptive characters. Fitness of between-species hybrids usually sharply decreases with the divergence time of the concerned species and the divergence depth, which still allows for a successful crossing differs among principal clades of vertebrates. Recently, a review of hybridization events among distinct lizard species revealed that lizards belong to vertebrates with a highly developed ability to hybridize. In spite of this, reliable reports of experimental hybridizations between genetically fairly divergent species are only exceptional. Here, we show the results of the crossing of two distinct allopatric species of eyelid geckos possessing temperature sex determination and lacking sex chromosomes: Eublepharis macularius distributed in Pakistan/Afghanistan area and E. angramainyu, which inhabits Mesopotamia and adjacent areas. We demonstrated that F1 hybrids were viable and fertile, and the introgression of E. angramainyu genes into the E. macularius genome can be enabled via a backcrossing. The examined hybrids (except those of the F2 generation) displayed neither malformations nor a reduced survival. Analyses of morphometric and coloration traits confirmed phenotypic distinctness of both parental species and their F1 hybrids. These findings contrast with long-term geographic and an evolutionary separation of the studied species. Thus, the occurrence of fertile hybrids of comparably divergent species, such as E. angramainyu and E. macularius, may also be expected in other taxa of squamates. This would violate the current estimates of species diversity in lizards.
- MeSH
- druhová specificita MeSH
- fenotyp * MeSH
- fertilita genetika MeSH
- genetická variace * MeSH
- hybridizace genetická genetika MeSH
- ještěři genetika MeSH
- pohlavní chromozomy MeSH
- zvířata MeSH
- Check Tag
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
BACKGROUND: A significant fraction of mammalian genomes is composed of endogenous retroviral (ERV) sequences that are formed by germline infiltration of various retroviruses. In contrast to other retroviral genera, lentiviruses only rarely form ERV copies. We performed a computational search aimed at identification of novel endogenous lentiviruses in vertebrate genomes. FINDINGS: Using the in silico strategy, we have screened 104 publicly available vertebrate genomes for the presence of endogenous lentivirus sequences. In addition to the previously described cases, the search revealed the presence of endogenous lentivirus in the genome of Malayan colugo (Galeopterus variegatus). At least three complete copies of this virus, denoted ELVgv, were detected in the colugo genome, and approximately one hundred solo LTR sequences. The assembled consensus sequence of ELVgv had typical lentivirus genome organization including three predicted accessory genes. Phylogenetic analysis placed this virus as a distinct subgroup within the lentivirus genus. The time of insertion into the dermopteran lineage was estimated to be more than thirteen million years ago. CONCLUSIONS: We report the discovery of the first endogenous lentivirus in the mammalian order Dermoptera, which is a taxon close to the Primates. Lentiviruses have infiltrated the mammalian germline several times across millions of years. The colugo virus described here represents possibly the oldest documented endogenization event and its discovery can lead to new insights into lentivirus evolution. This is also the first report of an endogenous lentivirus in an Asian mammal, indicating a long-term presence of this retrovirus family in Asian continent.
- MeSH
- endogenní retroviry klasifikace genetika MeSH
- fylogeneze MeSH
- Lentivirus klasifikace genetika MeSH
- molekulární evoluce MeSH
- pořadí genů MeSH
- savci virologie MeSH
- virové geny MeSH
- výpočetní biologie MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Geografické názvy
- Malajsie MeSH
It is notable that the occurrence of multiple sex chromosomes differs significantly between major lineages of amniote vertebrates. In this respect, birds are especially conspicuous, as multiple sex chromosomes have not been observed in this lineage so far. On the other hand, in mammals, multiple sex chromosomes have evolved many times independently. We hypothesize that this contrast can be related to the different involvement of sex-specific sex chromosomes in female meiosis subjected to the female meiotic drive under male versus female heterogamety. Essentially, the male-specific Y chromosome is not involved in female meiosis and is therefore sheltered against the effects of the female meiotic drive affecting the X chromosome and autosomes. Conversely, the Z and W sex chromosomes are both present in female meiosis. Nonrandom segregation of these sex chromosomes as a consequence of their rearrangements connected with the emergence of multiple sex chromosomes would result in a biased sex ratio, which should be penalized by selection. Therefore, the emergence of multiple sex chromosomes should be less constrained in the lineages with male rather than female heterogamety. Our broader phylogenetic comparison across amniotes supports this prediction. We suggest that our results are consistent with the widespread occurrence of female meiotic drive in amniotes.
- MeSH
- fylogeneze MeSH
- meióza fyziologie MeSH
- modely genetické MeSH
- plazi genetika MeSH
- pohlavní chromozomy genetika MeSH
- ptáci genetika MeSH
- savci genetika MeSH
- segregace chromozomů fyziologie MeSH
- typy dědičnosti genetika fyziologie MeSH
- zvířata MeSH
- Check Tag
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Among bird species, the most studied major histocompatibility complex (MHC) is the chicken MHC. Although the number of studies on MHC in free-ranging species is increasing, the knowledge on MHC variation in species closely related to chicken is required to understand the peculiarities of bird MHC evolution. Here we describe the variation of MHC class IIB (MHCIIB) exon 2 in a population of the Grey partridge (Perdix perdix), a species of high conservation concern throughout Europe and an emerging galliform model in studies of sexual selection. We found 12 alleles in 108 individuals, but in comparison to other birds surprisingly many sites show signatures of historical positive selection. Individuals displayed between two to four alleles both on genomic and complementary DNA, suggesting the presence of two functional MHCIIB loci. Recombination and gene conversion appear to be involved in generating MHCIIB diversity in the Grey partridge; two recombination breakpoints and several gene conversion events were detected. In phylogenetic analysis of galliform MHCIIB, the Grey partridge alleles do not cluster together, but are scattered through the tree instead. Thus, our results indicate that the Grey partridge MHCIIB is comparable to most other galliforms in terms of copy number and population polymorphism.
- MeSH
- alely MeSH
- druhová specificita MeSH
- exony genetika MeSH
- fylogeneze MeSH
- Galliformes genetika MeSH
- genová konverze * MeSH
- MHC antigeny II. třídy chemie genetika MeSH
- molekulární sekvence - údaje MeSH
- polymorfismus genetický * MeSH
- pravděpodobnostní funkce MeSH
- regulace genové exprese MeSH
- rekombinace genetická genetika MeSH
- sekvence aminokyselin MeSH
- sekvence nukleotidů MeSH
- sekvenční seřazení MeSH
- selekce (genetika) * MeSH
- substituce aminokyselin genetika MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Názvy látek
- MHC antigeny II. třídy MeSH