Since the publication of the first chicken genome sequence, we have encountered genes playing key roles in mammalian immunology, but being seemingly absent in birds. One of those was, until recently, Foxp3, the master transcription factor of regulatory T cells in mammals. Therefore, avian regulatory T cell research is still poorly standardized. In this study we identify a chicken ortholog of Foxp3 We prove sequence homology with known mammalian and sauropsid sequences, but also reveal differences in major domains. Expression profiling shows an association of Foxp3 and CD25 expression levels in CD4+CD25+ peripheral T cells and identifies a CD4-CD25+Foxp3high subset of thymic lymphocytes that likely represents yet undescribed avian regulatory T precursor cells. We conclude that Foxp3 is existent in chickens and that it shares certain functional characteristics with its mammalian ortholog. Nevertheless, pathways for regulatory T cell development and Foxp3 function are likely to differ between mammals and birds. The identification and characterization of chicken Foxp3 will help to define avian regulatory T cells and to analyze their functional properties and thereby advance the field of avian immunology.
- MeSH
- aktivace lymfocytů imunologie MeSH
- buněčná diferenciace imunologie MeSH
- forkhead transkripční faktory genetika MeSH
- genom genetika MeSH
- kur domácí genetika imunologie MeSH
- receptor interleukinu-2 - alfa-podjednotka metabolismus MeSH
- regulační T-lymfocyty imunologie MeSH
- sekvence aminokyselin genetika MeSH
- sekvence nukleotidů MeSH
- sekvenční analýza DNA MeSH
- sekvenční homologie MeSH
- sekvenční seřazení MeSH
- stanovení celkové genové exprese MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
The unicellular trypanosomatids belong to the phylum Euglenozoa and all known species are obligate parasites. Distinct lineages infect plants, invertebrates, and vertebrates, including humans. Genome data for marine diplonemids, together with freshwater euglenids and free-living kinetoplastids, the closest known nonparasitic relatives to trypanosomatids, recently became available. Robust phylogenetic reconstructions across Euglenozoa are now possible and place the results of parasite-focused studies into an evolutionary context. Here we discuss recent advances in identifying the factors shaping the evolution of Euglenozoa, focusing on ancestral features generally considered parasite-specific. Remarkably, most of these predate the transition(s) to parasitism, suggesting that the presence of certain preconditions makes a significant lifestyle change more likely.
- MeSH
- biologická evoluce * MeSH
- datové soubory jako téma MeSH
- Euglenozoa klasifikace genetika MeSH
- fylogeneze MeSH
- genom genetika MeSH
- infekce prvoky kmene Euglenozoa parazitologie MeSH
- lidé MeSH
- paraziti klasifikace genetika MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- přehledy MeSH
The widely distributed ray-finned fish genus Carassius is very well known due to its unique biological characteristics such as polyploidy, clonality, and/or interspecies hybridization. These biological characteristics have enabled Carassius species to be successfully widespread over relatively short period of evolutionary time. Therefore, this fish model deserves to be the center of attention in the research field. Some studies have already described the Carassius karyotype, but results are inconsistent in the number of morphological categories for individual chromosomes. We investigated three focal species: Carassius auratus, C. carassius and C. gibelio with the aim to describe their standardized diploid karyotypes, and to study their evolutionary relationships using cytogenetic tools. We measured length (q+plength) of each chromosome and calculated centromeric index (i value). We found: (i) The relationship between q+plength and i value showed higher similarity of C. auratus and C. carassius. (ii) The variability of i value within each chromosome expressed by means of the first quartile (Q1) up to the third quartile (Q3) showed higher similarity of C. carassius and C. gibelio. (iii) The fluorescent in situ hybridization (FISH) analysis revealed higher similarity of C. auratus and C. gibelio. (iv) Standardized karyotype formula described using median value (Q2) showed differentiation among all investigated species: C. auratus had 24 metacentric (m), 40 submetacentric (sm), 2 subtelocentric (st), 2 acrocentric (a) and 32 telocentric (T) chromosomes (24m+40sm+2st+2a+32T); C. carassius: 16m+34sm+8st+42T; and C. gibelio: 16m+22sm+10st+2a+50T. (v) We developed R scripts applicable for the description of standardized karyotype for any other species. The diverse results indicated unprecedented complex genomic and chromosomal architecture in the genus Carassius probably influenced by its unique biological characteristics which make the study of evolutionary relationships more difficult than it has been originally postulated.
- MeSH
- chromozomy genetika MeSH
- diploidie MeSH
- fylogeneze MeSH
- genetická variace genetika MeSH
- genom genetika MeSH
- hybridizace in situ fluorescenční metody MeSH
- kapři genetika MeSH
- karas zlatý genetika MeSH
- karyotyp MeSH
- karyotypizace metody MeSH
- mapování chromozomů metody MeSH
- polyploidie MeSH
- ryby genetika MeSH
- zvířata MeSH
- Check Tag
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
Vydání první 12 nečíslovaných stran : ilustrace (některé barevné) ; 30 cm
Naučný komiks pro děti, který se zaměřuje na dějiny genetiky a na genom a DNA.
- Konspekt
- Obecná genetika. Obecná cytogenetika. Evoluce
- Literatura pro děti a mládež (naučná)
- NLK Obory
- genetika, lékařská genetika
- dějiny lékařství
- NLK Publikační typ
- komiksy
- literatura pro děti a mládež
First edition 12 nečíslovaných stran : ilustrace (některé barevné) ; 30 cm
A comic book for children, that teaches about the history of genetics and about the genome and the DNA.
- Konspekt
- Obecná genetika. Obecná cytogenetika. Evoluce
- Literatura pro děti a mládež (naučná)
- NLK Obory
- genetika, lékařská genetika
- dějiny lékařství
- NLK Publikační typ
- komiksy
- literatura pro děti a mládež
Streptomyces sp. TR1341 was isolated from the sputum of a man with a history of lung and kidney tuberculosis, recurrent respiratory infections, and COPD. It produces secondary metabolites associated with cytotoxicity and immune response modulation. In this study, we complement our previous results by identifying the genetic features associated with the production of these secondary metabolites and other characteristics that could benefit the strain during its colonization of human tissues (virulence factors, modification of the host immune response, or the production of siderophores). We performed a comparative phylogenetic analysis to identify the genetic features that are shared by environmental isolates and human respiratory pathogens. The results showed a high genomic similarity of Streptomyces sp. TR1341 to the plant-associated Streptomyces sp. endophyte_N2, inferring a soil origin of the strain. Putative virulence genes, such as mammalian cell entry (mce) genes were not detected in the TR1341's genome. The presence of a type VII secretion system, distinct from the ones found in Mycobacterium species, suggests a different colonization strategy than the one used by other actinomycete lung pathogens. We identified a higher diversity of genes related to iron acquisition and demonstrated that the strain produces ferrioxamine B in vitro. These results indicate that TR1341 may have an advantage in colonizing environments that are low in iron, such as human tissue.
- MeSH
- fylogeneze MeSH
- genetické techniky MeSH
- genom genetika MeSH
- geny genetika MeSH
- lidé MeSH
- plíce mikrobiologie MeSH
- počet mikrobiálních kolonií metody MeSH
- Streptomyces * genetika izolace a purifikace MeSH
- tkáně mikrobiologie MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Our novel Python-based tool EVANGELIST allows the visualization of GC and repeats percentages along chromosomes in sequenced genomes and has enabled us to perform quantitative large-scale analyses on the chromosome level in fish and other vertebrates. This is a different approach from the prevailing analyses, i.e., analyses of GC% in the coding sequences that make up not more than 2% in human. We identified GC content (GC%) elevations in microchromosomes in ancient fish lineages similar to avian microchromosomes and a large variability in the relationship between the chromosome size and their GC% across fish lineages. This raises the question as to what extent does the chromosome size drive GC% as posited by the currently accepted explanation based on the recombination rate. We ascribe the differences found across fishes to varying GC% of repetitive sequences. Generally, our results suggest that the GC% of repeats and proportion of repeats are independent of the chromosome size. This leaves an open space for another mechanism driving the GC evolution in vertebrates.
- MeSH
- chromozomy genetika MeSH
- cytogenetika * MeSH
- genom genetika MeSH
- molekulární evoluce * MeSH
- obratlovci klasifikace genetika MeSH
- ptáci klasifikace genetika MeSH
- rekombinace genetická genetika MeSH
- repetitivní sekvence nukleových kyselin MeSH
- ryby klasifikace genetika MeSH
- zastoupení bazí genetika MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Myxozoans are highly diverse and globally distributed cnidarian endoparasites in freshwater and marine habitats. They have adopted a heteroxenous life cycle, including invertebrate and fish hosts, and have been associated with diseases in aquaculture and wild fish stocks. Despite their importance, genomic resources of myxozoans have proven difficult to obtain due to their miniaturized and derived genome character and close associations with fish tissues. The first 'omic' datasets have now become the main resource for a better understanding of host-parasite interactions, virulence, and diversity, but also the evolutionary history of myxozoans. In this review, we discuss recent genomic advances in the field and outline outstanding questions to be answered with continuous and improved efforts of generating myxozoan genomic data.
- MeSH
- genom genetika MeSH
- genomika trendy MeSH
- Myxozoa klasifikace genetika patogenita MeSH
- parazitární nemoci parazitologie přenos MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- přehledy MeSH
The evolutionary forces shaping life history divergence within species are largely unknown. Turquoise killifish display differences in lifespan among wild populations, representing an ideal natural experiment in evolution and diversification of life history. By combining genome sequencing and population genetics, we investigate the evolutionary forces shaping lifespan among wild turquoise killifish populations. We generate an improved reference genome assembly and identify genes under positive and purifying selection, as well as those evolving neutrally. Short-lived populations from the outer margin of the species range have small population size and accumulate deleterious mutations in genes significantly enriched in the WNT signaling pathway, neurodegeneration, cancer and the mTOR pathway. We propose that limited population size due to habitat fragmentation and repeated population bottlenecks, by increasing the genome-wide mutation load, exacerbates the effects of mutation accumulation and cumulatively contribute to the short adult lifespan.
- MeSH
- akumulace mutací * MeSH
- biologická evoluce MeSH
- dlouhověkost genetika MeSH
- ekosystém MeSH
- Fundulidae MeSH
- genom genetika MeSH
- hustota populace * MeSH
- modely u zvířat MeSH
- molekulární evoluce * MeSH
- stárnutí genetika MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
