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1.
ISME J ; 18(1)2024 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-38691426

RESUMO

DPANN archaea are a diverse group of microorganisms that are thought to rely on an ectosymbiotic lifestyle; however, the cell biology of these cell-cell interactions remains largely unknown. We applied live-cell imaging and cryo-electron tomography to the DPANN archaeon Nanobdella aerobiophila and its host, revealing two distinct life cycle stages. Free cells possess archaella and are motile. Ectobiotic cells are intimately linked with the host through an elaborate attachment organelle. Our data suggest that free cells may actively seek a new host, while the ectobiotic state is adapted to mediate intricate interaction with the host.


Assuntos
Simbiose , Estágios do Ciclo de Vida , Microscopia Crioeletrônica , Nanoarchaeota/crescimento & desenvolvimento , Nanoarchaeota/genética , Tomografia com Microscopia Eletrônica
2.
Nat Commun ; 15(1): 3747, 2024 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-38702310

RESUMO

In malaria parasites, the regulation of mRNA translation, storage and degradation during development and life-stage transitions remains largely unknown. Here, we functionally characterized the DEAD-box RNA helicase PfDOZI in P. falciparum. Disruption of pfdozi enhanced asexual proliferation but reduced sexual commitment and impaired gametocyte development. By quantitative transcriptomics, we show that PfDOZI is involved in the regulation of invasion-related genes and sexual stage-specific genes during different developmental stages. PfDOZI predominantly participates in processing body-like mRNPs in schizonts but germ cell granule-like mRNPs in gametocytes to impose opposing actions of degradation and protection on different mRNA targets. We further show the formation of stress granule-like mRNPs during nutritional deprivation, highlighting an essential role of PfDOZI-associated mRNPs in stress response. We demonstrate that PfDOZI participates in distinct mRNPs to maintain mRNA homeostasis in response to life-stage transition and environmental changes by differentially executing post-transcriptional regulation on the target mRNAs.


Assuntos
RNA Helicases DEAD-box , Plasmodium falciparum , Proteínas de Protozoários , RNA Mensageiro , RNA Helicases DEAD-box/metabolismo , RNA Helicases DEAD-box/genética , Plasmodium falciparum/genética , Plasmodium falciparum/metabolismo , Plasmodium falciparum/crescimento & desenvolvimento , RNA Mensageiro/metabolismo , RNA Mensageiro/genética , Proteínas de Protozoários/metabolismo , Proteínas de Protozoários/genética , Ribonucleoproteínas/metabolismo , Ribonucleoproteínas/genética , Estágios do Ciclo de Vida/genética , RNA de Protozoário/metabolismo , RNA de Protozoário/genética , Estabilidade de RNA , Humanos , Malária Falciparum/parasitologia
3.
PLoS One ; 19(5): e0299154, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38709802

RESUMO

The fall armyworm (FAW), Spodoptera frugiperda (JE Smith) (Lepidoptera: Noctuidae), an invasive agricultural pest, has significantly impacted crop yields across Africa. This study investigated the relationship between temperature and FAW life history traits, employing life cycle modeling at temperatures of 20, 25, 28, 30, and 32°C. The development time for eggs, larvae, and pupae varied from 0-3 days, 10-18 days, and 7-16 days, respectively. The optimal temperature range for immature stage survival and female fecundity was identified as 21-25°C, with the intrinsic rate of increase (rm) and gross reproductive rate (GRR) peaking at 25-28°C. Model validation confirmed the accuracy of these findings. The research further projected the Establishment Risk Index (ERI), Activity Index (AI), and Generation Index (GI) for FAW under current and future climates (2050 and 2070) using RCP 2.6 and RCP 8.5 scenarios. Results indicate that RCP 2.6 leads to a reduction in high-risk FAW areas, particularly in central Africa. Conversely, RCP 8.5 suggests an increase in areas conducive to FAW activity. These findings highlight the impact of climate policy on pest dynamics and the importance of incorporating climatic factors into pest management strategies. The study predicts a potential decrease in FAW prevalence in West Africa by 2070 under aggressive climate mitigation, providing a basis for future FAW management approaches.


Assuntos
Estágios do Ciclo de Vida , Spodoptera , Temperatura , Zea mays , Animais , Spodoptera/fisiologia , Spodoptera/crescimento & desenvolvimento , África , Zea mays/parasitologia , Zea mays/crescimento & desenvolvimento , Tábuas de Vida , Feminino , Larva/fisiologia , Larva/crescimento & desenvolvimento
4.
J Invertebr Pathol ; 204: 108105, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38614293

RESUMO

Myxozoans are obligate parasites with complex life cycles, typically infecting fish and annelids. Here, we examined annelids from fish farm pond sediments in the Beit Shean Valley, in the Syrian-African Rift Valley, Israel, for myxozoan infections. We examined 1486 oligochaetes, and found 74 (5 %) were infected with actinospore stages. We used mitochondrial 16S sequencing to infer identity of 25 infected annelids as species of Potamothrix, Psammoryctides, Tubifex and Dero. We identified 7 myxozoan types from collective groups Neoactinomyxum and Sphaeractinomyxon, and characterized them by small subunit ribosomal DNA sequencing. The Neoactinomyxum type was genetically most similar (∼93 %) to cyprinid fish-infecting Myxobolus spp. The six Sphaeractinomyxon types were genetically similar (93-100 %) to Mugilid-infecting Myxobolus spp.; with one being the previously unknown actinospore stage of a myxospore that infects mullet from aquaculture from the Israeli coast of the Mediterranean Sea. As the farm pond system is artificial and geographically isolated from the Mediterranean, the presence of at least seven myxozoans in their annelid hosts demonstrates introduction and establishment of these parasites in a novel, brackish environment.


Assuntos
Aquicultura , Myxozoa , Lagoas , Animais , Myxozoa/genética , Myxozoa/fisiologia , Lagoas/parasitologia , Estágios do Ciclo de Vida , Doenças Parasitárias em Animais/parasitologia , Israel , Doenças dos Peixes/parasitologia
5.
Sci Rep ; 14(1): 7797, 2024 04 02.
Artigo em Inglês | MEDLINE | ID: mdl-38565565

RESUMO

Bacterial pathogens adapt and replicate within host cells, while host cells develop mechanisms to eliminate them. Using a dual proteomic approach, we characterized the intra-macrophage proteome of the facultative intracellular pathogen, Francisella novicida. More than 900 Francisella proteins were identified in infected macrophages after a 10-h infection. Biotin biosynthesis-related proteins were upregulated, emphasizing the role of biotin-associated genes in Francisella replication. Conversely, proteins encoded by the Francisella pathogenicity island (FPI) were downregulated, supporting the importance of the F. tularensis Type VI Secretion System for vacuole escape, not cytosolic replication. In the host cell, over 300 proteins showed differential expression among the 6200 identified during infection. The most upregulated host protein was cis-aconitate decarboxylase IRG1, known for itaconate production with antimicrobial properties in Francisella. Surprisingly, disrupting IRG1 expression did not impact Francisella's intracellular life cycle, suggesting redundancy with other immune proteins or inclusion in larger complexes. Over-representation analysis highlighted cell-cell contact and actin polymerization in macrophage deregulated proteins. Using flow cytometry and live cell imaging, we demonstrated that merocytophagy involves diverse cell-to-cell contacts and actin polymerization-dependent processes. These findings lay the groundwork for further exploration of merocytophagy and its molecular mechanisms in future research.Data are available via ProteomeXchange with identifier PXD035145.


Assuntos
Francisella tularensis , Tularemia , Animais , Francisella tularensis/genética , Actinas/metabolismo , Biotina/metabolismo , Proteômica , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Macrófagos/metabolismo , Estágios do Ciclo de Vida , Tularemia/microbiologia , Ilhas Genômicas
6.
Environ Monit Assess ; 196(5): 416, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38570390

RESUMO

The research conducts a life cycle assessment (LCA) on wastewater treatment (WWT) methods-membrane bioreactor (MBR), soil biotechnology (SBT), and bio-electrochemical constructed wetlands (BCW)-in comparison with the conventional activated sludge process (ASP). Employing SimaPro v9.5 with a cradle-to-gate system boundary, the analysis utilizes the IMPACT 2002 + method, employing per cubic meter of treated wastewater as the functional unit. The analysis shows that SBT exhibits the lowest environmental impacts among the considered WWT methods. The global warming potential was 0.0996 kg CO2 eq. for SBT, 1.33 kg CO2 eq. for MBR, 0.131 kg CO2 eq. for BCW, and 0.544 kg CO2 eq. for ASP. BCW demonstrates a 75.91% decrease, while MBR exhibits a 144.48% increase compared to ASP. Notably, electricity consumption emerges as the primary contributor to environmental impact in MBR and ASP. The resource impact category varies with a 138.15% increase in MBR and an 83.41% decrease in SBT compared to ASP. Additionally, the research indicates that the high human health impact observed in MBR results mainly from increased carcinogens (0.00176 kg C2H3Cl eq.), non-carcinogens (0.01 kg C2H3Cl eq.), and ionizing radiation (3.34 Bq C-14 eq.). The findings underscore the importance of considering treatment efficiency and broader environmental implications in selecting WWT methods. As the world emphasizes sustainability, such LCA studies provide valuable insights for making informed decisions in wastewater management.


Assuntos
Eliminação de Resíduos Líquidos , Águas Residuárias , Humanos , Animais , Eliminação de Resíduos Líquidos/métodos , Dióxido de Carbono , Monitoramento Ambiental , Solo , Estágios do Ciclo de Vida
7.
PeerJ ; 12: e17161, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38560466

RESUMO

The life history of a parasite describes its partitioning of assimilated resources into growth, reproduction, and transmission effort, and its precise timing of developmental events. The life cycle, in contrast, charts the sequence of morphological stages from feeding to the transmission forms. Phenotypic plasticity in life history traits can reveal how parasites confront variable environments within hosts. Within the protist phylum Apicomplexa major clades include the malaria parasites, coccidians, and most diverse, the gregarines (with likely millions of species). Studies on life history variation of gregarines are rare. Therefore, life history traits were examined for the gregarine Monocystis perplexa in its host, the invasive earthworm Amynthas agrestis at three sites in northern Vermont, United States of America. An important value of this system is the short life-span of the hosts, with only seven months from hatching to mass mortality; we were thus able to examine life history variation during the entire life cycle of both host and parasite. Earthworms were collected (N = 968 over 33 sample periods during one host season), then parasites of all life stages were counted, and sexual and transmission stages measured, for each earthworm. All traits varied substantially among individual earthworm hosts and across the sites. Across sites, timing of first appearance of infected earthworms, date when transmission stage (oocysts packed within gametocysts) appeared, date when number of both feeding (trophic) cells and gametocysts were at maximum, and date when 100% of earthworms were infected differed from 2-8 weeks, surprising variation for a short season available for parasite development. The maximal size of mating cells varied among hosts and across sites and this is reflected in the number of oocysts produced by the gametocyst. A negative trade-off was observed for the number of oocysts and their size. Several patterns were striking: (1) Prevalence reached 100% at all sites by mid season, only one to three weeks after parasites first appeared in the earthworms. (2) The number of parasites per host was large, reaching 300 × 103 cells in some hosts, and such high numbers were present even when parasites first appeared in the host. (3) At one site, few infected earthworms produced any oocysts. (4) The transmission rate to reach such high density of parasites in hosts needed to be very high for a microbe, from >0.33% to >34.3% across the three sites. Monocystis was one of the first protist parasites to have its life cycle described (early 19th century), but these results suggest the long-accepted life cycle of Monocystis could be incomplete, such that the parasites may be transmitted vertically (within the earthworm's eggs) as well as horizontally (leading to 100% prevalence) and merogony (asexual replication) could be present, not recognized for Monocystis, leading to high parasitemia even very early in the host's season.


Assuntos
Apicomplexa , Características de História de Vida , Oligoquetos , Parasitos , Animais , Oligoquetos/parasitologia , Reprodução , Estágios do Ciclo de Vida , Oocistos
8.
Br Dent J ; 236(7): 545-551, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38609622

RESUMO

Background Health care is a significant contributor to climate change. Global pressure for a change towards a more sustainable way of providing dental health care has resulted in the creation of the Green Impact Toolkit, which is comprised of a list of suggested changes that dental practices can make to become more sustainable in a number of categories, such as procurement, waste and water.Aims To compare the effectiveness of changes suggested by the Green Impact Toolkit.Materials and methods A comparative life cycle assessment (LCA) was conducted using the Ecoinvent database v3.8 and these data were processed using OpenLCA v1.10.3 software.Results The carbon footprint per patient was significantly reduced after the recommendations were implemented. For instance, using water from a rainwater collection tank instead of the mains supply saved 30 g CO2eq (carbon dioxide equivalents) per patient, a 90% reduction in carbon footprint.Discussion This comparative LCA identified some effective changes which can be easily made by a dental practice. Nevertheless, some actions require some initial financial investment and may be difficult to implement in a busy modern dental practice setting.Conclusion The findings from this study can be used to guide dental practices to making choices which are more sustainable and eco-friendly in the future.


Assuntos
Pegada de Carbono , Água , Humanos , Animais , Software , Estágios do Ciclo de Vida
9.
Lancet Planet Health ; 8 Suppl 1: S18, 2024 04.
Artigo em Inglês | MEDLINE | ID: mdl-38632913

RESUMO

BACKGROUND: Given the urgency of transitioning towards sustainable nutrition, dietary shifts that provide co-benefits to human health and the environment are imperative. There is currently no database of the environmental impacts of foods that reflects Canada's unique geographical and agri-climatic context and regional inputs and emissions. To determine sustainable diets, harmonising nutritional considerations with environmental impacts is also essential for an equitable comparison of foods. We aimed to develop a Canadian Food Life Cycle Inventory database and a multidimensional index to enable a joint assessment of the health and environmental impacts of foods in Canada. METHODS: The Canadian Food Life Cycle Inventory database uses life cycle assessment methodology to evaluate environmental impacts. The datasets mirror Canada's food consumption patterns, averaging the spectrum of agricultural practices weighted by domestic production and import shares. The database is structured according to the nomenclature and categorisation of the Canadian Nutrient File. Environmental sustainability is assessed using a cradle-to-grave approach, including indicators such as greenhouse gas emissions, eutrophication, particulate matter, freshwater usage, land use, non-renewable energy consumption, and food loss and waste. Environmental impacts are quantified through an environmental impact score (EIS) assigned to each impact category for a given food. The EIS-nutrition (EIS-N) integrates the evaluation of nutritional quality with environmental impacts using Nutri-Score, a validated food nutrient-profiling tool. The EIS-N is modelled as a ratio of the EIS to the Nutri-Score values. FINDINGS: Preliminary results show the greatest environmental impacts for animal-based foods, particularly beef, in agreement with current literature. Foods with greater nutritional quality also generally show greater environmental sustainability, with some exceptions for particular impact categories. INTERPRETATION: The database and index have potential to serve as powerful tools to support researchers, policy makers, and consumers, harnessing big data to drive efficient food and climate solutions for systems transformation. FUNDING: Province of Ontario and University of Toronto, CIHR SMART Healthy Cities Training Platform, and University of Toronto's Temerty Faculty of Medicine.


Assuntos
Meio Ambiente , Alimentos , Animais , Bovinos , Humanos , Dieta , Estágios do Ciclo de Vida , Ontário
10.
PeerJ ; 12: e17087, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38623496

RESUMO

Background: Spodoptera frugiperda (FAW) is a pest that poses a significant threat to corn production worldwide, causing millions of dollars in losses. The species has evolved into two strains (corn and rice) that differ in their genetics, reproductive isolation, and resistance to insecticides and Bacillus thuringiensis endotoxins. The microbiota plays an important role in insects' physiology, nutrient acquisition, and response to chemical and biological controls. Several studies have been carried out on FAW microbiota from larvae guts using laboratory or field samples and a couple of studies have analyzed the corn strain microbiota across its life cycle. This investigation reveals the first comparison between corn strain (CS) and rice strain (RS) of FAW during different developmental insect stages and, more importantly, endosymbiont detection in both strains, highlighting the importance of studying both FAW populations and samples from different stages. Methods: The composition of microbiota during the life cycle of the FAW corn and rice strains was analyzed through high-throughput sequencing of the bacterial 16S rRNA gene using the MiSeq system. Additionally, culture-dependent techniques were used to isolate gut bacteria and the Transcribed Internal Spacer-ITS, 16S rRNA, and gyrB genes were examined to enhance bacterial identification. Results: Richness, diversity, and bacterial composition changed significantly across the life cycle of FAW. Most diversity was observed in eggs and males. Differences in gut microbiota diversity between CS and RS were minor. However, Leuconostoc, A2, Klebsiella, Lachnoclostridium, Spiroplasma, and Mucispirilum were mainly associated with RS and Colidextribacter, Pelomonas, Weissella, and Arsenophonus to CS, suggesting that FAW strains differ in several genera according to the host plant. Firmicutes and Proteobacteria were the dominant phyla during FAW metamorphosis. Illeobacterium, Ralstonia, and Burkholderia exhibited similar abundancies in both strains. Enterococcus was identified as a conserved taxon across the entire FAW life cycle. Microbiota core communities mainly consisted of Enterococcus and Illeobacterium. A positive correlation was found between Spiroplasma with RS (sampled from eggs, larvae, pupae, and adults) and Arsenophonus (sampled from eggs, larvae, and adults) with CS. Enterococcus mundtii was predominant in all developmental stages. Previous studies have suggested its importance in FAW response to B. thuringensis. Our results are relevant for the characterization of FAW corn and rice strains microbiota to develop new strategies for their control. Detection of Arsenophonus in CS and Spiroplasma in RS are promising for the improvement of this pest management, as these bacteria induce male killing and larvae fitness reduction in other Lepidoptera species.


Assuntos
Bacillus thuringiensis , Microbiota , Oryza , Animais , Masculino , Spodoptera/genética , Zea mays/genética , Oryza/genética , RNA Ribossômico 16S/genética , Estágios do Ciclo de Vida , Larva/genética , Bacillus thuringiensis/genética , Microbiota/genética
11.
Glob Chang Biol ; 30(4): e17285, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38660809

RESUMO

Climate warming is affecting the suitability and utilization of coastal habitats by marine fishes around the world. Phenological changes are an important indicator of population responses to climate-induced changes but remain difficult to detect in marine fish populations. The design of large-scale monitoring surveys does not allow fine-grained temporal inference of population responses, while the responses of ecologically and economically important species groups such as small pelagic fish are particularly sensitive to temporal resolution. Here, we use the longest, highest resolution time series of species composition and abundance of marine fishes in northern Europe to detect possible phenological shifts in the small pelagic North Sea herring. We detect a clear forward temporal shift in the phenology of nearshore habitat use by small juvenile North Sea herring. This forward shift might be linked to changes in water temperatures in the North Sea. We next assessed the robustness of the effects we found with respect to monitoring design. We find that reducing the temporal resolution of our data to reflect the resolution typical of larger surveys makes it difficult to detect phenological shifts and drastically reduces the effect sizes of environmental covariates such as seawater temperature. Our study therefore shows how local, long-term, high-resolution time series of fish catches are essential to understand the general phenological responses of marine fishes to climate warming and to define ecological indicators of system-level changes.


Assuntos
Mudança Climática , Ecossistema , Peixes , Animais , Mar do Norte , Peixes/fisiologia , Peixes/crescimento & desenvolvimento , Temperatura , Estágios do Ciclo de Vida , Estações do Ano
12.
Int J Biol Macromol ; 266(Pt 2): 131314, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38569995

RESUMO

Breeding of the black soldier fly is carried out to produce proteins. It is accompanied by releases during the life cycle of this insect. This work is a study of the valorization of these rejects through the production of chitins and chitosans with controlled characteristics. An extraction process is developed with an order of treatments and reaction conditions that provide chitins with high contents. These contents increase as the stages of the life cycle progress and drop for the adult. However, the exuviae chitins present organic impurities which will be eliminated at the N-deacetylation reaction for pupe and after a purification treatment for chitosan from larval stages. All these chitins have an α structure although certain physicochemical characteristics of the larval exuviae chitins are close to those presented by γ chitin. The observed shifts are linked to the effect of impurities rather than to a difference in structure. N-deacetylation of chitins makes possible the valorization of all rejects by the production of pure chitosans with high yields which retain a porous structure for the exuviae and fibrous for the adult which allow complementary applications. These chitosans are highly to completely deacetylated and their molar masses can vary depending on the process and life stage.


Assuntos
Quitina , Quitosana , Quitosana/química , Animais , Quitina/química , Dípteros/metabolismo , Dípteros/química , Dípteros/crescimento & desenvolvimento , Acetilação , Larva , Cruzamento , Estágios do Ciclo de Vida , Fenômenos Químicos
13.
Ecotoxicol Environ Saf ; 277: 116355, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38669871

RESUMO

The neonicotinoid insecticide thiamethoxam (TMX) is widely used to protect crops against insect pests. Despite some desirable properties such as its low toxicity to birds and mammals, concerns have been raised about its toxicity to non-target arthropods, including freshwater insects like chironomids. Whereas multiple studies have investigated chronic effects of neonicotinoids in chironomid larvae at standardized laboratory conditions, a better understanding of their chronic toxicity under variable temperatures and exposure is needed for coherent extrapolation from the laboratory to the field. Here, we developed a quantitative mechanistic effect model for Chironomus riparius, to simulate the species' life history under dynamic temperatures and exposure concentrations of TMX. Laboratory experiments at four different temperatures (12, 15, 20, 23 °C) and TMX concentrations between 4 and 51 µg/L were used to calibrate the model. Observed concentration-dependent effects of TMX in C. riparius included slower growth, later emergence, and higher mortality rates with increasing concentrations. Furthermore, besides a typical accelerating effect on the organisms' growth and development, higher temperatures further increased the effects associated with TMX. With some data-informed modeling decisions, most prominently the inclusion of a size dependence that makes larger animals more sensitive to TMX, the model was parametrized to convincingly reproduce the data. Experiments at both a constant (20 °C) and a dynamically increasing temperature (15-23 °C) with pulsed exposure were used to validate the model. Finally, the model was used to simulate realistic exposure conditions using two reference exposure scenarios measured in Missouri and Nebraska, utilizing a moving time window (MTW) and either a constant temperature (20 °C) or the measured temperature profiles belonging to each respective scenario. Minimum exposure multiplication factors leading to a 10% effect (EP10) in the survival at pupation, i.e., the most sensitive endpoint found in this study, were 25.67 and 21.87 for the Missouri scenario and 38.58 and 44.64 for the Nebraska scenario, when using the respective temperature assumptions. While the results illustrate that the use of real temperature scenarios does not systematically modify the EPx in the same direction (making it either more or less conservative when used as a risk indicator), the advantage of this approach is that it increases the realism and thus reduces the uncertainty associated with the model predictions.


Assuntos
Chironomidae , Inseticidas , Larva , Temperatura , Tiametoxam , Animais , Tiametoxam/toxicidade , Chironomidae/efeitos dos fármacos , Inseticidas/toxicidade , Larva/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Estágios do Ciclo de Vida/efeitos dos fármacos , Neonicotinoides/toxicidade
14.
PLoS Pathog ; 20(4): e1011906, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38669269

RESUMO

The apicomplexan parasite Cryptosporidium is a leading cause of childhood diarrhea in developing countries. Current treatment options are inadequate and multiple preclinical compounds are being actively pursued as potential drugs for cryptosporidiosis. Unlike most apicomplexans, Cryptosporidium spp. sequentially replicate asexually and then sexually within a single host to complete their lifecycles. Anti-cryptosporidial compounds are generally identified or tested through in vitro phenotypic assays that only assess the asexual stages. Therefore, compounds that specifically target the sexual stages remain unexplored. In this study, we leveraged the ReFRAME drug repurposing library against a newly devised multi-readout imaging assay to identify small-molecule compounds that modulate macrogamont differentiation and maturation. RNA-seq studies confirmed selective modulation of macrogamont differentiation for 10 identified compounds (9 inhibitors and 1 accelerator). The collective transcriptomic profiles of these compounds indicates that translational repression accompanies Cryptosporidium sexual differentiation, which we validated experimentally. Additionally, cross comparison of the RNA-seq data with promoter sequence analysis for stage-specific genes converged on a key role for an Apetala 2 (AP2) transcription factor (cgd2_3490) in differentiation into macrogamonts. Finally, drug annotation for the ReFRAME hits indicates that an elevated supply of energy equivalence in the host cell is critical for macrogamont formation.


Assuntos
Criptosporidiose , Cryptosporidium , Estágios do Ciclo de Vida , Proteínas de Protozoários , Criptosporidiose/parasitologia , Criptosporidiose/tratamento farmacológico , Proteínas de Protozoários/metabolismo , Proteínas de Protozoários/genética , Estágios do Ciclo de Vida/efeitos dos fármacos , Cryptosporidium/efeitos dos fármacos , Cryptosporidium/genética , Cryptosporidium/metabolismo , Fatores de Transcrição/metabolismo , Fatores de Transcrição/genética , Animais , Humanos , Bibliotecas de Moléculas Pequenas/farmacologia
15.
Theor Popul Biol ; 157: 86-117, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38615922

RESUMO

We approach the questions, what part of evolutionary change results from selection, and what is the adaptive information flow into a population undergoing selection, as a problem of quantifying the divergence of typical trajectories realized under selection from the expected dynamics of their counterparts under a null stochastic-process model representing the absence of selection. This approach starts with a formulation of adaptation in terms of information and from that identifies selection from the genetic parameters that generate information flow; it is the reverse of a historical approach that defines selection in terms of fitness, and then identifies adaptive characters as those amplified in relative frequency by fitness. Adaptive information is a relative entropy on distributions of histories computed directly from the generators of stochastic evolutionary population processes, which in large population limits can be approximated by its leading exponential dependence as a large-deviation function. We study a particular class of generators that represent the genetic dependence of explicit transitions around reproductive cycles in terms of stoichiometry, familiar from chemical reaction networks. Following Smith (2023), which showed that partitioning evolutionary events among genetically distinct realizations of lifecycles yields a more consistent causal analysis through the Price equation than the construction from units of selection and fitness, here we show that it likewise yields more complete evolutionary information measures.


Assuntos
Evolução Biológica , Aptidão Genética , Seleção Genética , Modelos Genéticos , Processos Estocásticos , Genética Populacional , Estágios do Ciclo de Vida , Dinâmica Populacional
16.
Environ Sci Pollut Res Int ; 31(21): 31467-31478, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38635093

RESUMO

Titanium dioxide nanoparticle (TiO2-NP) exposure has raised significant concern due to their potential toxicity and adverse ecological impacts. Despite their ubiquitous presence in various environmental compartments, the long-term consequences of TiO2-NPs remain poorly understood. In this study, we combined data of in vivo toxicity and modeling to investigate the potential negative impacts of TiO2-NP exposure. We employed the nematode Caenorhabditis elegans, an environmental organism, to conduct a full life cycle TiO2-NP toxicity assays. Moreover, to assess the potential impact of TiO2-NP toxicity on population dynamics, we applied a stage-constructed matrix population model (MPM). Results showed that TiO2-NPs caused significant reductions in reproduction, survival, and growth of parental C. elegans (P0) at the examined concentrations. Moreover, these toxic effects were even more pronounced in the subsequent generation (F1) when exposed to TiO2-NPs. Furthermore, parental TiO2-NP exposure resulted in significant toxicity in non-exposed C. elegans progeny (TiO2-NPs free), adversely affecting their reproduction, survival, and growth. MPM analysis revealed decreased transition probabilities of surviving (Pi), growth (Gi), and fertility (Fi) in scenarios with TiO2-NP exposure. Additionally, the population growth rate (λmax) was found to be less than 1 in both P0 and F1, indicating a declining population trend after successive generations. Sensitivity analysis pinpointed L1 larvae as the most vulnerable stage, significantly contributing to the observed population decline in both P0 and F1 generations under TiO2-NP exposure. Our findings provide insight into the potential risk of an environmental organism like nematode by life cycle exposure to TiO2-NPs.


Assuntos
Caenorhabditis elegans , Titânio , Animais , Titânio/toxicidade , Caenorhabditis elegans/efeitos dos fármacos , Reprodução/efeitos dos fármacos , Nanopartículas Metálicas/toxicidade , Nanopartículas/toxicidade , Estágios do Ciclo de Vida/efeitos dos fármacos
17.
PLoS One ; 19(4): e0300438, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38687812

RESUMO

Gryllus bimaculatus (Orthoptera: Gryllidae) is widely considered an excellent nutrient source for food and feed. Despite its economic importance, there is limited information on the impact of temperature on the bionomics of this cricket to guide its effective and sustainable mass production in its geographical range. The biological parameters of G. bimaculatus were investigated at eight different temperatures ranging from 20-40˚C. The Insect Life-Cycle Modelling (ILCYM) program was used to fit linear and non-linear functions to the data to describe the influence of temperature on life history parameters and its farmability under the current and projected climate for 2050. Our results revealed that G. bimaculatus was able to complete its lifecycle in the temperature range of 20°C to 37°C with a maximum finite rate of population increase (= 1.14) at 35°C. The developmental time of G. bimaculatus decreased with increasing temperature. The least developmental time and mortality were attained at 32°C. The highest wet length and mass of G. bimaculatus occurred at 32°C. The lowest temperature threshold for G. bimaculatus egg and nymph development was approximated using linear regression functions to be at 15.9°C and 16.2°C with a temperature constant of 108.7 and 555.6 degree days. The maximum fecundity (2301.98 eggs per female), net reproductive rate (988.42 daughters/ generation), and intrinsic rate of natural increase (0.134 days) were recorded at 32°C and the shortest doubling of 5.2 days was observed at 35°C. Based on our findings G. bimaculatus can be farmed in countries with temperatures ranging between 20 and 37°C around the globe. These findings will help the cricket farmers understand and project the cricket population dynamics around the world as influenced by temperature, and as such, will contribute to more efficient farming.


Assuntos
Gryllidae , Temperatura , Animais , Gryllidae/crescimento & desenvolvimento , Gryllidae/fisiologia , Feminino , Masculino , Estágios do Ciclo de Vida
18.
Zootaxa ; 5418(2): 140-158, 2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38480366

RESUMO

The life cycle of Cerroneuroterus minutulus (Giraud, 1859), a species previously known only from its asexual generation, is closed. Our study demonstrates that C. minutulus exhibits the heterogony typical of Cynipini species, with alternating sexual and asexual generations. The identity of the sexual generation is demonstrated by laboratory experiments and confirmed by molecular data, with Cerroneuroterus aggregatus (Wachtl, 1880) determined to be the sexual generation, and junior synonym, of Cerroneuroterus minutulus (Giraud, 1859). Illustrations and diagnoses for adults and galls, observations on biology and distribution information are provided as is a detailed redescription of the sexual generation of C. minutulus.


Assuntos
Himenópteros , Quercus , Vespas , Animais , Estágios do Ciclo de Vida
19.
BMC Vet Res ; 20(1): 104, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38491459

RESUMO

BACKGROUND: members of the genus Sarcocystis are intracellular obligate protozoan parasites classified within the phylum Apicomplexa and have an obligate heteroxenous life cycle involving two hosts. A more comprehensive understanding of the prevalence and geographic range of different Sarcocystis species in marine ecosystems is needed globally and nationally. Hence, the objective of this study was to document the incidence of Sarcocystis infection in sharks within the aquarium ecosystem of Egypt and to identify the species through the characterization of the SSU rDNA gene. METHODS: All organs of the mako shark specimen underwent macroscopic screening to detect the existence of a Sarcocystis cyst. Ten cysts were collected from the intestine and processed separately to extract the genomic DNA. The polymerase chain reaction (PCR) was accomplished by amplifying a specific 18S ribosomal RNA (rRNA) gene fragment. Subsequently, the resulting amplicons were subjected to purification and sequencing processes. RESULTS: Macroscopic examination of the mako shark intestinal wall sample revealed the presence of Sarcocystis cysts of various sizes and shapes, and sequencing of the amplicons from Sarcocystis DNA revealed a 100% nucleotide identity with the sequence of Sarcocystis tenella recorded from sheep in Iran; The mako shark sequence has been deposited in the GeneBank with the accession number OQ721979. This study presents the first scientific evidence demonstrating the presence of the Sarcocystis parasite in sharks, thereby documenting this specific marine species as a novel intermediate host in the Sarcocystis life cycle. CONCLUSIONS: This is the first identification of Sarcocystis infection in sharks, and we anticipate it will be an essential study for future screenings and establishing effective management measures for this disease in aquatic ecosystems.


Assuntos
Sarcocystis , Tubarões , Animais , Ovinos/genética , Sarcocystis/genética , Ecossistema , Tubarões/genética , Filogenia , Oceano Índico , DNA Ribossômico , Estágios do Ciclo de Vida
20.
Parasitol Res ; 123(3): 147, 2024 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-38433153

RESUMO

Strigea falconis is a common parasite of birds of prey and owls widely distributed in the Holarctic. We aimed to characterise S. falconis from Iceland via integrative taxonomic approach and to contribute to the understanding of its circulation in the Holarctic. We recovered adult S. falconis from two gyrfalcons (Falco rusticolus) collected in 2011 and 2012 in Iceland (Reykjanes Peninsula, Westfjords) and characterised them by morphological and molecular genetic (D2 of rDNA, cox1, ND1 of the mDNA) methods. We provide the first species record of S. falconis in Iceland which to the best of our knowledge is its northernmost distributional range. The presence of S. falconis in Iceland is surprising, as there are no suitable intermediate hosts allowing completion of its life cycle. Gyrfalcons are fully sedentary in Iceland; thus, the only plausible explanation is that they acquired their infection by preying upon migratory birds arriving from Europe. Our data indicate that the most likely candidates are Anseriformes and Charadriiformes. Also, we corroborate the wide geographical distribution of S. falconis, as we found a high degree of similarity between our haplotypes and sequences of mesocercariae from frogs in France and of a metacercaria from Turdus naumanni in Japan, and adults from Buteo buteo and Circus aeruginosus from the Czech Republic. The case of Strigea falconis shows the advantages of a complex life cycle and also depicts its pitfalls when a parasite is introduced to a new area with no suitable intermediate hosts. In Iceland, gyrfalcons are apparently dead-end hosts for S. falconis.


Assuntos
Falconiformes , Trematódeos , Animais , Islândia/epidemiologia , Trematódeos/genética , Europa (Continente) , Estágios do Ciclo de Vida
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