Several divergent Cryptosporidium parvum subtypes have emerged in people in recent years, but their infectivity, pathogenicity, and genetic characteristics are unclear. In the present study, IFN-γ knockout C57BL/6 (GKO) mice were infected with the novel IIoA15G1 and IIpA11 subtypes of C. parvum and the common IIaA17G2R1 subtype. The genomes of these isolates were sequenced and compared with each other. Further gene tagging and deletion were performed on the most polymorphic virulence-associated cgd8_5420 gene encoding a hypothetical protein using the CRISPR/Cas9 technology. IIpA11 and IIoA15G1 were highly infectious in GKO mice, with an ID50 of 2.4 and 3.6 oocysts, respectively. The duration of oocyst shedding for IIpA11 (>58.0 ± 1.4 d) and IIoA15G1 (>57.5 ± 0.9 d) was significantly longer than for IIaA17G2R1 (5.5 ± 0.9 d; p < 0.001). One of the mice infected with IIpA11 died on day 33 post infection. The genomes of IIaA17G2R1, IIoA15G1, and IIpA11 had 203, 46839, and 47,122 single nucleotide polymorphisms, respectively, compared to C. parvum IOWA II. In contrast, only 3,361 nucleotide differences were found between IIoA15G1 and IIpA11, with several genes encoding invasion-associated mucin glycoproteins and cgd8_5420 encoding a secretory protein being highly polymorphic. The latter is mainly expressed in trophozoites, merozoites, and macrogametes. Deletion of this gene reduced the intensity of IIpA11 infection and increased the survival of infected mice. Therefore, the emerging IIoA15G1 and IIpA11 subtypes have divergent genomes compared to common IIa subtypes and are highly infectious and pathogenic in GKO mice. Several secretory proteins, including a variant protein encoded by the subtelomeric cgd8_5420 gene, are associated with differences in virulence between the two subtypes.
- Klíčová slova
- CRISPR/Cas9, Cryptosporidium, animal model, genomics, virulence,
- MeSH
- Cryptosporidium parvum * genetika patogenita klasifikace MeSH
- faktory virulence * genetika metabolismus MeSH
- genom protozoální MeSH
- kryptosporidióza * parazitologie MeSH
- myši inbrední C57BL MeSH
- myši knockoutované MeSH
- myši MeSH
- oocysty MeSH
- protozoální proteiny * genetika metabolismus MeSH
- virulence MeSH
- zvířata MeSH
- Check Tag
- myši MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Názvy látek
- faktory virulence * MeSH
- protozoální proteiny * MeSH
The leaves above the ear serve as a major source of carbohydrates for grain filling in maize. However, increasing the number of leaves above the ear to strengthen the source and improve maize yield remains challenging in modern maize breeding. Here, we clone the causative gene of the quantitative trait locus (QTL) associated with the number of leaves above the ear. The causative gene is the previously reported MADS-box domain-encoding gene Tunicate1 (Tu1), which is responsible for the phenotype of pod corn or Tunicate maize. We show that Tu1 can substantially increase the leaf number above the ear while maintaining the source‒sink balance. A distal upstream 5-base pair (bp) insertion of Tu1 originating from a popcorn landrace enhances its transcription, coregulates its plastochron activators and repressors, and increases the number of leaves above the ear. Field tests demonstrate that the 5-bp insertion of Tu1 can increase grain yields by 11.4% and 9.5% under regular and dense planting conditions, respectively. The discovery of this favorable Tu1 allele from landraces suggests that landraces represent a valuable resource for high-yield breeding of maize.
- MeSH
- alely MeSH
- fenotyp MeSH
- geneticky modifikované rostliny MeSH
- kukuřice setá * genetika růst a vývoj metabolismus MeSH
- listy rostlin * genetika růst a vývoj metabolismus MeSH
- lokus kvantitativního znaku * MeSH
- proteiny domény MADS genetika metabolismus MeSH
- regulace genové exprese u rostlin * MeSH
- rostlinné proteiny * genetika metabolismus MeSH
- šlechtění rostlin MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Názvy látek
- proteiny domény MADS MeSH
- rostlinné proteiny * MeSH
Symbiotic relationships between eukaryotes and prokaryotes played pivotal roles in the evolution of life and drove the emergence of specialized symbiotic structures in animals, plants and fungi. The host-evolved symbiotic structures of microbial eukaryotes - the vast majority of such hosts in nature - remain largely unstudied. Here we describe highly structured symbiosomes within three free-living anaerobic protists (Anaeramoeba spp.). We dissect this symbiosis using complete genome sequencing and transcriptomics of host and symbiont cells coupled with fluorescence in situ hybridization, and 3D reconstruction using focused-ion-beam scanning electron microscopy. The emergence of the symbiosome is underpinned by expansion of gene families encoding regulators of membrane trafficking and phagosomal maturation and extensive bacteria-to-eukaryote lateral transfer. The symbionts reside deep within a symbiosomal membrane network that enables metabolic syntrophy by precisely positioning sulfate-reducing bacteria alongside host hydrogenosomes. Importantly, the symbionts maintain connections to the Anaeramoeba plasma membrane, blurring traditional boundaries between ecto- and endosymbiosis.
In most studied eukaryotes, chromosomes are monocentric, with centromere activity confined to a single region. However, the rush family (Juncaceae) includes species with both monocentric (Juncus) and holocentric (Luzula) chromosomes, where centromere activity is distributed along the entire chromosome length. Here, we combine chromosome-scale genome assembly, epigenetic analysis, immuno-FISH and super-resolution microscopy to study the transition to holocentricity in Luzula sylvatica. We report repeat-based holocentromeres with an irregular distribution of features along the chromosomes. Luzula sylvatica holocentromeres are predominantly associated with two satellite DNA repeats (Lusy1 and Lusy2), while CENH3 also binds satellite-free gene-poor regions. Comparative repeat analysis suggests that Lusy1 plays a crucial role in centromere function across most Luzula species. Furthermore, synteny analysis between L. sylvatica (n = 6) and Juncus effusus (n = 21) suggests that holocentric chromosomes in Luzula could have arisen from chromosome fusions of ancestral monocentric chromosomes, accompanied by the expansion of CENH3-associated satellite repeats.
- MeSH
- centromera * genetika MeSH
- chromozomy rostlin * genetika MeSH
- DNA rostlinná genetika MeSH
- genom rostlinný MeSH
- hybridizace in situ fluorescenční MeSH
- molekulární evoluce MeSH
- repetitivní sekvence nukleových kyselin genetika MeSH
- satelitní DNA * genetika MeSH
- syntenie MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Názvy látek
- DNA rostlinná MeSH
- satelitní DNA * MeSH
OBJECTIVES: We performed a retrospective analysis of MRSA isolates collected at the university equine clinic including clinical isolates from 2008 to 2021 and screening environmental, equine and personnel isolates from 2016. METHODS: Screening and clinical samples were cultured on Brilliance MRSA 2 and Columbia agar (Oxoid), respectively, with enrichment for environmental samples. Antimicrobial susceptibility was assessed by disc diffusion. All the isolates were characterized by spa typing. Eighteen selected isolates were subjected to WGS with subsequent wgMLST clonal analysis. RESULTS: Among 75 MRSA isolates, five spa types were identified, the majority (n = 67; 89.33%) was t011. All isolates were resistant to cefoxitin and ampicillin and carried the mecA gene. In addition, the isolates were resistant to tetracycline (n = 74; 98.67%), gentamicin (n = 70; 93.33%), enrofloxacin (n = 54; 72.00%), sulfamethoxazole-trimethoprim (n = 5; 6.67%) and lincomycin (n = 3; 4.00%) with corresponding genetic markers for the resistance detected in the sequenced isolates. All 18 sequenced isolates belonged to ST398, 16 carried SCCmec type IVa and two carried SCCmec type Vc (5C2&5). Further, isolates carried aur, hlgA, hlgB and hlgC virulence genes, and five isolates carried sak and scn genes, which are part of the immune evasion cluster. Close genetic relatedness was found between isolates from the staff of the clinic and clinical samples of horses. CONCLUSIONS: Repeated introduction and long-term persistence of the equine LA-MRSA subclone (ST398-MRSA-IVa/Vc(5C2&5), t011) among the infected horses at the equine clinic with the colonization of personnel, and the environment contamination that might contribute to transmission were observed.
- MeSH
- antibakteriální látky * farmakologie MeSH
- bakteriální proteiny genetika MeSH
- koně mikrobiologie MeSH
- lidé MeSH
- methicilin rezistentní Staphylococcus aureus * genetika izolace a purifikace účinky léků klasifikace MeSH
- mikrobiální testy citlivosti * MeSH
- mikrobiologie životního prostředí MeSH
- mnohočetná bakteriální léková rezistence genetika MeSH
- multilokusová sekvenční typizace MeSH
- nemoci koní mikrobiologie MeSH
- nemocnice veterinární MeSH
- retrospektivní studie MeSH
- sekvenování celého genomu MeSH
- stafylokokové infekce * mikrobiologie veterinární epidemiologie MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Názvy látek
- antibakteriální látky * MeSH
- bakteriální proteiny MeSH
A novel negative-sense single-stranded RNA virus showing genetic similarity to viruses of the genus Rubodvirus has been found in raspberry plants in the Czech Republic and has tentatively been named raspberry rubodvirus 1 (RaRV1). Phylogenetic analysis confirmed its clustering within the group, albeit distantly related to other members. A screening of 679 plant and 168 arthropod samples from the Czech Republic and Norway revealed RaRV1 in 10 raspberry shrubs, one batch of Aphis idaei, and one individual of Orius minutus. Furthermore, a distinct isolate of this virus was found, sharing 95% amino acid identity in both the full nucleoprotein and partial sequence of the RNA-dependent RNA polymerase gene sequences, meeting the species demarcation criteria. This discovery marks the first reported instance of a rubodvirus infecting raspberry plants. Although transmission experiments under experimental conditions were unsuccessful, positive detection of the virus in some insects suggests their potential role as vectors for the virus.
- Klíčová slova
- HTS, Rubus, aphids, raspberry, rubodvirus,
- MeSH
- fylogeneze * MeSH
- negativní RNA-viry genetika klasifikace izolace a purifikace MeSH
- nemoci rostlin * virologie MeSH
- RNA virová genetika MeSH
- Rubus * virologie MeSH
- sekvenční analýza DNA MeSH
- shluková analýza MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Geografické názvy
- Česká republika MeSH
- Norsko MeSH
- Názvy látek
- RNA virová MeSH
Cryptosporidium is a leading cause of diarrheal-related deaths in children, especially in resource-poor settings. It also targets the immunocompromised, chronically infecting people living with HIV and primary immunodeficiencies. There is no vaccine or effective treatment. Although it is known from human cases and animal models that CD4+ T cells play a role in curbing Cryptosporidium, the role of CD8+ T cells remains to be defined. Using a Cryptosporidium tyzzeri mouse model, we show that gut-resident CD8+ intraepithelial lymphocytes (IELs) confer resistance to parasite growth. CD8+ IELs express and depend on the ligand-dependent transcription factor aryl hydrocarbon receptor (AHR). AHR deficiency reduces CD8+ IELs, decreases their cytotoxicity, and worsens infection. Transfer of CD8+ IELs rescues severely immunodeficient mice from death following Cryptosporidium challenge. Finally, dietary supplementation of the AHR pro-ligand indole-3-carbinol in newborn mice promotes resistance to infection. Therefore, common dietary metabolites augment the host immune response to cryptosporidiosis, protecting against disease.
- Klíčová slova
- Cryptosporidium, aryl hydrocarbon receptor, diet, indole-3-carbinol, intraepithelial lymphocytes,
- MeSH
- CD8-pozitivní T-lymfocyty MeSH
- Cryptosporidium * MeSH
- dieta MeSH
- dítě MeSH
- kryptosporidióza * parazitologie MeSH
- lidé MeSH
- ligandy MeSH
- myši MeSH
- zvířata MeSH
- Check Tag
- dítě MeSH
- lidé MeSH
- myši MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Názvy látek
- ligandy MeSH
UPF1-like helicases play roles in telomeric heterochromatin formation and X-chromosome inactivation, and also in monogenic variant surface glycoprotein (VSG) expression via VSG exclusion-factor-2 (VEX2), a UPF1-related protein in the African trypanosome. We show that VEX2 associates with chromatin specifically at the single active VSG expression site on chromosome 6, forming an allele-selective connection, via VEX1, to the trans-splicing locus on chromosome 9, physically bridging two chromosomes and the VSG transcription and splicing compartments. We further show that the VEX-complex is multimeric and self-regulates turnover to tightly control its abundance. Using single cell transcriptomics following VEX2-depletion, we observed simultaneous derepression of many other telomeric VSGs and multi-allelic VSG expression in individual cells. Thus, an allele-selective, inter-chromosomal, and self-limiting VEX1-2 bridge supports monogenic VSG expression and multi-allelic VSG exclusion.
- MeSH
- alely MeSH
- membránové glykoproteiny genetika MeSH
- telomery metabolismus MeSH
- Trypanosoma brucei brucei * metabolismus MeSH
- Trypanosoma * metabolismus MeSH
- trypanosomové variantní povrchové glykoproteiny metabolismus MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Názvy látek
- membránové glykoproteiny MeSH
- trypanosomové variantní povrchové glykoproteiny MeSH
As climate change continues, species pushed outside their physiological tolerance limits must adapt or face extinction. When change is rapid, adaptation will largely harness ancestral variation, making the availability and characteristics of that variation of critical importance. Here, we used whole-genome sequencing and genetic-environment association analyses to identify adaptive variation and its significance in the context of future climates in a small Palearctic mammal, the bank vole (Clethrionomys glareolus). We found that peripheral populations of bank vole in Britain are already at the extreme bounds of potential genetic adaptation and may require an influx of adaptive variation in order to respond. Analyses of adaptive loci suggest regional differences in climate variables select for variants that influence patterns of population adaptive resilience, including genes associated with antioxidant defense, and support a pattern of thermal/hypoxic cross-adaptation. Our findings indicate that understanding potential shifts in genomic composition in response to climate change may be key to predicting species' fate under future climates.
- MeSH
- Arvicolinae genetika MeSH
- fyziologická adaptace genetika MeSH
- genom MeSH
- hlodavci * genetika MeSH
- klimatické změny MeSH
- savci * genetika MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
To date, most molecular investigations of schistosomatids have focused principally on blood flukes (schistosomes) of humans. Despite the clinical importance of cercarial dermatitis in humans caused by Trichobilharzia regenti and the serious neuropathologic disease that this parasite causes in its permissive avian hosts and accidental mammalian hosts, almost nothing is known about the molecular aspects of how this fluke invades its hosts, migrates in host tissues and how it interacts with its hosts' immune system. Here, we explored selected aspects using a transcriptomic-bioinformatic approach. To do this, we sequenced, assembled and annotated the transcriptome representing two consecutive life stages (cercariae and schistosomula) of T. regenti involved in the first phases of infection of the avian host. We identified key biological and metabolic pathways specific to each of these two developmental stages and also undertook comparative analyses using data available for taxonomically related blood flukes of the genus Schistosoma. Detailed comparative analyses revealed the unique involvement of carbohydrate metabolism, translation and amino acid metabolism, and calcium in T. regenti cercariae during their invasion and in growth and development, as well as the roles of cell adhesion molecules, microaerobic metabolism (citrate cycle and oxidative phosphorylation), peptidases (cathepsins) and other histolytic and lysozomal proteins in schistosomula during their particular migration in neural tissues of the avian host. In conclusion, the present transcriptomic exploration provides new and significant insights into the molecular biology of T. regenti, which should underpin future genomic and proteomic investigations of T. regenti and, importantly, provides a useful starting point for a range of comparative studies of schistosomatids and other trematodes.
- MeSH
- biologická adaptace * MeSH
- interakce hostitele a patogenu * MeSH
- kachny parazitologie MeSH
- metabolické sítě a dráhy genetika MeSH
- molekulární sekvence - údaje MeSH
- Schistosomatidae genetika růst a vývoj MeSH
- sekvenční analýza DNA MeSH
- stadia vývoje MeSH
- stanovení celkové genové exprese * MeSH
- výpočetní biologie * MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
