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1.
Evolution ; 77(1): 1-12, 2023 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-36622707

RESUMO

In some asexual species, parthenogenetic females occasionally produce males, which may strongly affect the evolution and maintenance of asexuality if they cross with related sexuals and transmit genes causing asexuality to their offspring ("contagious parthenogenesis"). How these males arise in the first place has remained enigmatic, especially in species with sex chromosomes. Here, we test the hypothesis that rare, asexually produced males of the crustacean Artemia parthenogenetica are produced by recombination between the Z and W sex chromosomes during non-clonal parthenogenesis, resulting in ZZ males through loss of heterozygosity at the sex determination locus. We used RAD-sequencing to compare asexual mothers with their male and female offspring. Markers on several sex-chromosome scaffolds indeed lost heterozygosity in all male but no female offspring, suggesting that they correspond to the sex-determining region. Other sex-chromosome scaffolds lost heterozygosity in only a part of the male offspring, consistent with recombination occurring at a variable location. Alternative hypotheses for the production of these males (such as partial or total hemizygosity of the Z) could be excluded. Rare males are thus produced because recombination is not entirely suppressed during parthenogenesis in A. parthenogenetica. This finding may contribute to explaining the maintenance of recombination in these asexuals.


Assuntos
Artemia , Partenogênese , Feminino , Animais , Masculino , Artemia/genética , Partenogênese/genética , Heterozigoto , Recombinação Genética , Reprodução Assexuada
2.
J Environ Manage ; 329: 117092, 2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-36571950

RESUMO

Artemia egg shell loaded with nano-magnesium (shell-Mg) can be used to recover phosphorus from wastewater. The exhausted Artemia egg shell-Mg (denoted as shell-Mg-P) can be used as a slow-release fertilizer for phosphorus reuse. However, due to the coexistence of heavy metal ions in the environment, the application of slow-release fertilizer for phosphorus removal and reuse may have potential risks. In this paper, the potential risks of Pb2+, Cd2+, Zn2+ and Cu2+ in phosphorus wastewater and soil were studied from the formation and application process of shell-Mg-P. The result showed that shell-Mg adsorbed Pb2+, Cd2+, Zn2+ and Cu2+ in phosphate wastewater during the formation of shell-Mg-P and became shell-Mg-P-metal hybrid biomaterial. Although the experiment proved that the existence of heavy metal ions did not affect the phosphorus slow-release behavior of slow-release fertilizer, but the heavy metal ions in the shell-Mg-P-metal were also slow released. The pot experiment results confirmed that the slow-release phosphorus fertilizers (shell-Mg-P and shell-Mg-P-metal) in the soil polluted in low concentration of heavy metals can reduce the amount of heavy metals in whole wheat seedlings and promote wheat seedling growth. However, the application of slow-release fertilizers increased the translocation efficiency (TFR to SL) of metal from root (R) to aboveground part (stem and leaves, SL), promoted the transportation of heavy metals from roots to the stems and leaves, and increased the safety risk of the wheat seedling edible. Therefore, besides the positive role of slow-release fertilizers in retaining heavy metals and reducing the amount of heavy metals in whole seedlings, the risk that it may aggravate the translocation of heavy metals to stems and leaves should be paid more attention, so as to ensure the safe and reliable application of slow-release fertilizers.


Assuntos
Metais Pesados , Poluentes do Solo , Animais , Fertilizantes/análise , Fósforo , Artemia , Cádmio , Casca de Ovo/química , Chumbo , Poluentes do Solo/análise , Metais Pesados/análise , Medição de Risco , Solo , Triticum , Plântula/química
3.
Genes (Basel) ; 13(11)2022 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-36360234

RESUMO

The understanding of sex determination and differentiation in animals has recently made remarkable strides through the use of advanced research tools. At the gene level, the Mab-3-related transcription factor (Dmrt) gene family, which encodes for the typical DNA-binding doublesex/Mab-3 (DM) domain in their protein, is known for its contribution to sex determination and differentiation in insects. In this study, DNA-binding DM domain screening has identified eight transcripts from Artemia franciscana transcriptomic that encode proteins containing one conserved DNA-binding DM domain. The genome mapping confirmed that these eight transcripts are transcribed from six different loci on the A. franciscana genome assembly. One of those loci, the Af.dsx-4 locus, is closely related to Doublesex, a gene belonging to the Dmrt gene family. This locus could be transcribed into three alternative transcripts, namely Af.dsx4, Af.dsxF and Af.dsxM. While Af.dsx4 and Af.dsxF could putatively be translated to form an identical Af.dsxF protein of 186 aa long, Af.dsxM translates for an Af.dsxM protein of 289 aa long but shares a DNA-binding DM domain. Interestingly, Af.dsxF and Af.dsxM are confirmed as sex-specific transcripts, Af.dsxF is only present in females, and Af.dsxM is only present in male individuals. The results suggest that the sex-specific splicing mechanism of the doublesex described in insects is also present in A. franciscana. Af.dxs-4 locus can be used in further studies to clarify the sex determination pathways in A. fracnciscana.


Assuntos
Processamento Alternativo , Artemia , Animais , Feminino , Masculino , Artemia/genética , Splicing de RNA , DNA
4.
J Vis Exp ; (188)2022 10 11.
Artigo em Inglês | MEDLINE | ID: mdl-36314836

RESUMO

Natural products have been used since ancient times to produce medicines. Nowadays, there are plenty of chemotherapeutic drugs obtained from natural sources and used against a plethora of diseases. Unfortunately, most of these compounds often display systemic toxicity and adverse effects. In order to better evaluate the tolerability of selected potentially bioactive samples, brine shrimp (Artemia salina) is generally used as a model in lethality studies. The A. salina test is based on the ability of the studied bioactive compounds to kill the microcrustaceans in their larval stage (nauplii). This method represents a convenient starting point for cytotoxicity studies, as well as for the general toxicity screening of synthetic, semisynthetic, and natural products. It can be considered a simple, quick, and low-cost assay, compared to many other assays (in vitro cells or yeast strains, zebrafish, rodents) generally suitable for the aforementioned purposes; moreover, it can be easily performed even without any specific training. Overall, A. salina assay represents a useful tool for the preliminary toxicity evaluation of selected compounds and the bio-guided fractionation of natural product extracts.


Assuntos
Artemia , Produtos Biológicos , Animais , Peixe-Zebra , Bioensaio , Larva , Produtos Biológicos/farmacologia
5.
Aquat Toxicol ; 252: 106320, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36206704

RESUMO

Artemia spp. represent models species widely used in ecotoxicological studies due to its simple and fast manipulation in laboratory conditions that makes this crustacean well adaptable to several methodological approaches. Although cysts hatching, swimming behavior, reproductive success and mortality are the main endpoints used for the determination of toxicity, the detection of slight alterations induced by certain substances found at low concentrations in the environment may require more sensitive biomarkers. For this reason, the identification of DNA or chromosomal damages has been proposed as an additional and appreciable endpoint for the ecotoxicological assessment of environmental chemicals. Concerning Artemia models, only few studies indicated that the exposure to organic and inorganic compounds (i.e. pesticides, nanoparticles, bacterial products or heavy metals) can reduce the survival and fitness through the onset of DNA breaks or the dysregulation of key genes. In contrast, literature research revealed a lot of works primarily focusing on the mortality and hatching rates of Artemia nauplii and cysts despite the well-known low sensitivity of these species. The present review reports the current state of knowledge concerning the effects induced by various chemicals, including organic and inorganic compounds, on the common parameters and genotoxicity in both Artemia franciscana and Artemia salina. Advantages and limitations of Artemia spp. models in eco-toxicological investigations together with the most used classes of compounds are briefly discussed. Moreover, a mention is also addressed to scarce availability of literature data focusing on genotoxic effects and the great reliability of molecular approaches observed in this poorly sensitive model organism. Thus, the opportunity to take advantage of genotoxic analyses has also been highlighted, by suggesting this approach as a novel endpoint to be used for the eco-toxicological assessment of several stressors.


Assuntos
Cistos , Praguicidas , Poluentes Químicos da Água , Animais , Artemia , Poluentes Químicos da Água/toxicidade , Reprodutibilidade dos Testes , Praguicidas/farmacologia , Dano ao DNA , Biomarcadores
6.
Microbiol Spectr ; 10(5): e0268922, 2022 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-36154441

RESUMO

Indole signaling is viewed as a potential target for antivirulence therapy against antibiotic-resistant pathogens because of its link with the production of virulence factors. This study examined the antimicrobial and antivirulence properties of 44 indoles toward Vibrio campbellii. Based on the results, 17 halogenated indole analogues were selected, as they significantly improved the survival of brine shrimp larvae challenged with V. campbellii. Specifically, 6-bromoindole, 7-bromoindole, 4-fluoroindole, 5-iodoindole, and 7-iodoindole showed a high protective effect, improving the survival of brine shrimp to over 80% even at a low concentration of 10 µM. To explore the impact of selected indole analogues on bacterial virulence phenotypes, swimming motility, biofilm formation, protease activity, and hemolytic activity of V. campbellii were determined. The results showed that all of the 17 selected indole analogues decreased swimming motility at both 10 µM and 100 µM. Most of the indole analogues decreased biofilm formation at a concentration of 100 µM. In contrast, only a slightly decreased protease activity and no effect on hemolytic activity were observed at both concentrations. To our knowledge, this is the first study of the structure-activity relation of halogenated indole analogues with respect to virulence inhibition of a pathogenic bacterium in an in vivo host model system, and the results demonstrate the potential of these compounds in applications aiming at the protection of shrimp from vibriosis, a major disease in aquaculture. IMPORTANCE Bacterial diseases are a major problem in the aquaculture industry. In order to counter this problem, farmers have been using antibiotics, and this has led to the evolution and spread of antibiotic resistance. In order for the aquaculture industry to further grow in a sustainable way, novel and sustainable methods to control diseases are needed. We previously reported that indole signaling is a valid target for the development of novel therapies to control disease caused by Vibrio campbellii and related bacteria, which are among the major bacterial pathogens in aquaculture. In the present study, we identified indole analogues that are more potent in protecting brine shrimp (a model organism for shrimp) from V. campbellii. To our knowledge, this is the first study of the structure-activity relation of halogenated indole analogues with respect to virulence inhibition of a pathogenic bacterium in an in vivo host model system.


Assuntos
Anti-Infecciosos , Vibrio , Animais , Antibacterianos/farmacologia , Anti-Infecciosos/farmacologia , Artemia/microbiologia , Vida Livre de Germes , Indóis/farmacologia , Peptídeo Hidrolases/farmacologia , Virulência/genética , Fatores de Virulência/genética
7.
J Biol Inorg Chem ; 27(7): 611-629, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36149503

RESUMO

The pollution of aquatic ecosystems due to the elevated concentration of a variety of contaminants, such as metal ions, poses a threat to humankind, as these ecosystems are in high relevance with human activities and survivability. The exposure in heavy metal ions is responsible for many severe chronic and pathogenic diseases and some types of cancer as well. Metal ions of the groups 11 (Cu, Ag, Au), 12 (Zn, Cd, Hg), 14 (Sn, Pb) and 15 (Sb, Bi) highly interfere with proteins leading to DNA damage and oxidative stress. While, the detection of these contaminants is mainly based on physicochemical analysis, the chemical determination, however, is deemed ineffective in some cases because of their complex nature. The development of biological models for the evaluation of the presence of metal ions is an attractive solution, which provides more insights regarding their effects. The present work critically reviews the reports published regarding the toxicity assessment of heavy metal ions through Allium cepa and Artemia salina assays. The in vivo toxicity of the agents is not only dose depended, but it is also strongly affected by their ligand type. However, there is no comprehensive study which compares the biological effect of chemical agents against Allium cepa and Artemia salina. Reports that include metal ions and complexes interaction with either Allium cepa or Artemia salina bio-indicators are included in the review.


Assuntos
Mercúrio , Metais Pesados , Animais , Artemia/metabolismo , Cádmio/metabolismo , Química Bioinorgânica , Ecossistema , Humanos , Íons/metabolismo , Chumbo , Ligantes , Mercúrio/farmacologia , Metais Pesados/metabolismo , Metais Pesados/toxicidade , Cebolas
8.
Bull Environ Contam Toxicol ; 109(6): 1150-1154, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35997791

RESUMO

This study aims to describe a simple and environmentally friendly procedure for producing silver nanoparticles (AgNPs) using Paeonia kesrouanensis (P. kesrouanensis) extracts and to determine the toxic effect in the aquatic environment. The morphologies, size, size distributions, and structural properties were analyzed using SEM-EDX, TEM, DLS, zeta potential, FTIR, and XRD. AgNPs were applied to Artemia salina (A.salina), aquatic organism individuals at 7 different concentrations (0.0, 0.2, 1, 5, 10, 25, 50 mg/L) for 24, 48, and 72 h. AgNPs accumulation and elimination, ion release amounts, and the survival rates of organisms were determined at periods of 24, 48, and 72nd hours. The highest accumulation was observed at the 24th hour at the 50 mg/L exposure level. The survival rate decreased as exposure time increased at all concentrations.


Assuntos
Nanopartículas Metálicas , Paeonia , Humanos , Animais , Artemia , Prata/toxicidade , Prata/química , Nanopartículas Metálicas/toxicidade , Nanopartículas Metálicas/química , Extratos Vegetais/química
9.
Fish Shellfish Immunol ; 128: 38-49, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35917889

RESUMO

Nuclear factor-κB (NF-κB) plays a role as a rheostatic transcription factor in regulating intestinal inflammation, and its disruption or constitutive activation leads to inflammation and injury. However, the molecular mechanisms of NF-κB regulation remain largely unknown. In this study, the NF-κB-regulated host defenses against pathogen infections and facilitation of IL17 expression during stimulation with different bacteria were investigated. Intestinal inflammation was induced by dextran sulfate sodium, and NF-κB activity was inhibited in an intestinal injury model. Mannose receptor C type, ABF1/2, serpin B13, lysozyme, and ß-arrestin were significantly controlled by NF-κB in the inflamed intestinal tissue. High levels of NF-κB activation resulted in less pervasive intestinal damage and the maintenance of intestinal barrier integrity. Intestinal injury robustly increased the expression of IL17. NF-κB activation was enhanced by IL17 deficiency in the intestinal injury model. IL17 inhibition aggravated intestinal inflammation, leading to loss of epithelial architecture and the infiltration of inflammatory cells. These data suggest that NF-κB and IL17 play key mediator roles in the maintenance of gut epithelial integrity and immune homeostasis.


Assuntos
NF-kappa B , Serpinas , Animais , Artemia , Sulfato de Dextrana/metabolismo , Inflamação/induzido quimicamente , Inflamação/metabolismo , Mucosa Intestinal/metabolismo , Muramidase/metabolismo , NF-kappa B/metabolismo , Serpinas/metabolismo , beta-Arrestinas/metabolismo
10.
Chemosphere ; 307(Pt 4): 136094, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35995200

RESUMO

Polystyrene (PS) is selected as a representative nanoplastic and persistent pollutant for its difficult degradation and wide application. The environmental risk assessment of PS is obstructed by the toxic dye-based fluorescent PS, which false positives could be induced by the leakage of dye. For high biocompatibility, low toxicity, hydrophilicity, good water dispersibility, strong fluorescent stability, graphene oxide quantum dots (o-CQDs) are selected and embedded into PS microspheres, i.e., o-CQDs@PS, by microemulsion polymerization and denoted as CPS. Meanwhile, the sizes of CPS, e.g., 100, 150, and 200 nm, could be controlled by optimizing the type and number of water-soluble initiators. The anti-interference, low toxicity, and in vivo fluorescent tracing of CPS are proven by the coexistence of metals (including Fe2+, Fe3+, K+, Ba2+, Al3+, Zn2+, Mg2+, Ca2+, and Na+) on the fluorescence intensity of CPS, the growth of Chlorella pyrenoidosa and Artemia cysts as aquatic phytoplankton and zooplankton cultured with CPS, and the transfer of CPS from water into brine shrimp. In the concentration range of 0.1-100 mg/L, CPS can be quantitatively determined, which is suitable for coastal water and wastewater treatment plants. Therefore, CPS with standard size is suitable as reference material of PS.


Assuntos
Chlorella , Poluentes Ambientais , Nanosferas , Pontos Quânticos , Animais , Artemia/metabolismo , Poluentes Ambientais/metabolismo , Grafite , Microplásticos , Poliestirenos/toxicidade , Pontos Quânticos/toxicidade , Água/metabolismo
11.
Molecules ; 27(15)2022 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-35956946

RESUMO

Biomphalaria glabrata snails constitute the main vector of schistosomiasis in Brazil, and Bauhinia monandra Kurz, the leaves of which contain BmoLL lectin with biocidal action, is a plant widely found on continents in which the disease is endemic. This work describes the composition of B. monandra preparations and the effect on embryos and adult snails, their reproduction parameters and hemocytes. We also describe the results of a comet assay after B. glabrata exposure to sublethal concentrations of the preparations. Additionally, the effects of the preparations on S. mansoni cercariae and environmental monitoring with Artemia salina are described. In the chemical evaluation, cinnamic, flavonoid and saponin derivatives were detected in the two preparations assessed, namely the saline extract and the fraction. Both preparations were toxic to embryos in the blastula, gastrula, trochophore, veliger and hippo stages (LC50 of 0.042 and 0.0478; 0.0417 and 0.0419; 0.0897 and 0.1582; 0.3734 and 0.0974; 0.397 and 0.0970 mg/mL, respectively) and to adult snails (LC50 of 6.6 and 0.87 mg/mL, respectively), which were reproductively affected with decreased egg deposition. In blood cell analysis, characteristic cells for apoptosis, micronucleus and binucleation were detected, while for comet analysis, different degrees of nuclear damage were detected. The fraction was able to cause total mortality of the cercariae and did not present environmental toxicity. Therefore, B. monandra preparations are promising in combating schistosomiasis since they can control both the intermediate host and eliminate the infectious agent, besides being safe to the environment.


Assuntos
Bauhinia , Biomphalaria , Esquistossomose , Animais , Artemia , Folhas de Planta , Schistosoma mansoni
12.
Genetics ; 222(2)2022 09 30.
Artigo em Inglês | MEDLINE | ID: mdl-35977389

RESUMO

Eurasian brine shrimp (genus Artemia) have closely related sexual and asexual lineages of parthenogenetic females, which produce rare males at low frequencies. Although they are known to have ZW chromosomes, these are not well characterized, and it is unclear whether they are shared across the clade. Furthermore, the underlying genetic architecture of the transmission of asexuality, which can occur when rare males mate with closely related sexual females, is not well understood. We produced a chromosome-level assembly for the sexual Eurasian species Artemia sinica and characterized in detail the pair of sex chromosomes of this species. We combined this new assembly with short-read genomic data for the sexual species Artemia sp. Kazakhstan and several asexual lineages of Artemia parthenogenetica, allowing us to perform an in-depth characterization of sex-chromosome evolution across the genus. We identified a small differentiated region of the ZW pair that is shared by all sexual and asexual lineages, supporting the shared ancestry of the sex chromosomes. We also inferred that recombination suppression has spread to larger sections of the chromosome independently in the American and Eurasian lineages. Finally, we took advantage of a rare male, which we backcrossed to sexual females, to explore the genetic basis of asexuality. Our results suggest that parthenogenesis is likely partly controlled by a locus on the Z chromosome, highlighting the interplay between sex determination and asexuality.


Assuntos
Artemia , Partenogênese , Animais , Artemia/genética , Feminino , Genoma , Masculino , Partenogênese/genética , Reprodução/genética , Cromossomos Sexuais/genética
13.
J Ethnopharmacol ; 298: 115564, 2022 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-35940467

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Matcha green tea (Camellia sinensis) based-supplements have been widely used since they present a greater content of phenolic compounds than traditional green tea, which is popularly used in the treatment of diabetes. However, there are few studies on the effectiveness and safety of matcha supplements. AIM OF THE STUDY: This work aimed to evaluate the efficacy and safety of this supplement in endothelial cells (EA.hy926) in the hyperglycemic model and in vivo Artemia salina. MATERIALS AND METHODS: To assess the effect of Matcha herbal supplement (MHS), EA. hy926 endothelial cells were treated with 20 µg/mL of MHS for 24 h, in a hyperglycemic medium with 35 mM glucose. After treatment, cells were trypsinized and centrifuged at 4 °C and 47×g for 5 min. The pellet was used to determine the reaction products to thiobarbituric acid and the levels of nitric oxide. Electron transport chain activity and ATP levels were also evaluated. Intracellular pH, apoptosis, and mitochondrial membrane depolarization were evaluated by flow cytometry. MHS chemical characterization was performed by HPLC-UV and total phenolic content analysis. The evaluation of the antioxidant capacity of MHS was performed by 2,2-diphenyl-1-picrylhydrazyl radical scavenger assay. To determine the in vivo acute toxicity of MHS, an A. salina assay was conducted, using 0,2 mL of different concentrations of MHS (10, 50, 100, 250, 500, 750 and 1000 µg/mL). The LD50 values were obtained by interpolation of 50% (y = 50) of the dead individuals in the trend curves. RESULTS: Our data showed that MHS was able to avoid oxidative and nitrosative stress induced by hyperglycemia, demonstrating important antioxidant activity. However, it was observed that MHS reduced up to 90% the activity of the four-electron transport complexes, reducing the ATP production of the endothelial cells. In the toxicity assay performed in Artemia salina, MHS showed mild toxicity (LD50 = 0,4 mg/mL). The major compounds found in MHS were epigallocatechin gallate, epicatechin, rutin, kaempferol, and quercetin. CONCLUSIONS: This data draws attention to the fact that supplements with high content of phenolic compounds, capable of avoiding oxidative and nitrosative stress can have a dual effect and, simultaneously to antioxidant activity, can induce toxicity in different cell types.


Assuntos
Camellia sinensis , Trifosfato de Adenosina , Animais , Antioxidantes/análise , Antioxidantes/farmacologia , Artemia , Camellia sinensis/química , Suplementos Nutricionais/análise , Suplementos Nutricionais/toxicidade , Células Endoteliais , Humanos , Fenóis/análise , Fenóis/toxicidade , Chá/química
14.
FEMS Microbiol Ecol ; 98(10)2022 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-36036952

RESUMO

The microbial community associated with animals (microbiome) is essential for development, physiology, and health of host organisms. A critical step to understand the assembly of microbiomes is to determine how effectively bacteria colonize and establish within the host. Bacteria commonly colonize hosts through vertical transmission, passively from the environment, or through food consumption. Using the prey feeding method (PFM), we test transmittance of Bacillus velezensis, Pseudoalteromonas spiralis, and Vibrio alginolyticus to Nematostella vectensis using two prey, Artemia salina and Brachionus plicatilis. We compare PFM to a solution uptake method (SUM) to quantify the concentration of bacteria in these host organisms, with plate counts. Larvae had a similar uptake with SUM at 6 h but had greater concentrations at 48 h versus PFM. Juveniles acquired similar concentrations at 6 h for SUM and PFM using B. plicatilis and A. salina. At 2 days, the quantity of bacteria vectored from PFM increased. After 7 days the CFUs decreased 2-fold with B. plicatilis and A. salina relative to the 2-day concentrations, and further decreased after 14 days. Therefore, prey-mediated methods provide greater microbe transplantation than SUM after 24 h, supporting this approach as a more successful inoculation method of individual bacterial species.


Assuntos
Rotíferos , Anêmonas-do-Mar , Animais , Artemia/microbiologia , Bactérias/genética , Larva/microbiologia
15.
Am Nat ; 200(2): E52-E76, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35905400

RESUMO

AbstractDetermining how and how often asexual lineages emerge within sexual species is central to our understanding of sex-asex transitions and the long-term maintenance of sex. Asexuality can arise "by transmission" from an existing asexual lineage to a new one through different types of crosses. The occurrence of these crosses, cryptic sex, variations in ploidy, and recombination within asexuals greatly complicates the study of sex-asex transitions, as they preclude the use of standard phylogenetic methods and genetic distance metrics. In this study we show how to overcome these challenges by developing new approaches to investigate the origin of the various asexual lineages of the brine shrimp Artemia parthenogenetica. We use a large sample of asexuals, including all known polyploids, and their sexual relatives. We combine flow cytometry with mitochondrial and nuclear DNA data. We develop new genetic distance measures and methods to compare various scenarios describing the origin of the different lineages. We find that all diploid and polyploid A. parthenogenetica likely arose within the past 80,000 years through successive and nested hybridization events that involved backcrosses with different sexual species. All A. parthenogenetica have the same common ancestor and therefore likely carry the same asexuality gene(s) and reproduce by automixis. These findings radically change our view of sex-asex transitions in this group and show the importance of considering scenarios of asexuality by transmission. The methods developed are applicable to many other asexual taxa.


Assuntos
Artemia , Reprodução Assexuada , Animais , Artemia/genética , Partenogênese/genética , Filogenia , Poliploidia , Reprodução Assexuada/genética
16.
Sci Total Environ ; 842: 156807, 2022 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-35750161

RESUMO

This study evaluated the bioconcentration metrics, organ-specific distribution, and trophic consequences of silver nanoparticles along a Dunaliella salina-Artemia salina-Poecilia reticulata food chain. To this end, accumulation, tissue-specific distribution, bioconcentration and biomagnification factors, and trophic toxicity of AgNPs were quantitatively investigated along di- and tri-trophic food chains. Overall, silver accumulation increased markedly in intestine and liver tissues, carcass, and embryos of guppy fish with rising exposure concentrations and reducing trophic levels. Following trophic and waterborne exposure, AgNPs illustrated a regular tendency in following order: intestine > liver > embryos > carcass. BCF displayed values of 826, 131, and ≈ 1000 for microalgae, brine shrimp, and guppy fish, respectively. Moreover, BMF showed values <1.00 for 48-h post-hatched nauplii and guppy fish received AgNPs-exposed phytoplankton, yet >1.00 for the liver and whole body of guppy fish treated with AgNPs-exposed nauplii through algae and water, indicating that AgNPs could be biomagnified from the second to third trophic level, but not from the first to second or third levels. Furthermore, the waterborne and trophic exposure of AgNPs considerably induced oxidative stress and reproductive toxicity. Together, this study demonstrated that AgNPs could be biomagnified across trophic chain and consequently cause trophic toxicity.


Assuntos
Nanopartículas Metálicas , Poluentes Químicos da Água , Animais , Artemia , Peixes , Cadeia Alimentar , Nanopartículas Metálicas/toxicidade , Fitoplâncton , Prata/toxicidade , Poluentes Químicos da Água/toxicidade , Zooplâncton
17.
Dev Biol ; 489: 178-184, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35732224

RESUMO

The brine shrimp, Artemia franciscana, has a body plan composed of 11 thoracic segments, followed by 2 genital segments, and then 6 additional abdominal segments. Previous studies of Artemia reported that expression of the posterior-most Hox gene, Abdominal-B (Abd-B), is restricted to the genital segments and is not observed posteriorly in the abdomen at any developmental stage. This report was remarkable because it suggested that the Artemia abdomen posterior to the genital segments was a novel body region of 6 segments that bore no homology to any region in other crustaceans and was unique amongst arthropods in being a Hox-free segmented domain outside of the head. In this study, we used RT-PCR, antibody staining, and in situ hybridization on various stages of Artemia nauplii to show that Abd-B mRNA and protein are in fact expressed throughout the abdominal segments during Artemia development, but this expression later retracts to the two genital segments (G1, G2) and the T11 appendages. This suggests that Abd-B does play a role in specifying abdominal segment identity in all crustaceans that have been examined and suggests a common evolutionary origin for the crustacean abdomen.


Assuntos
Artemia , Proteínas de Homeodomínio , Abdome , Animais , Artemia/genética , Artemia/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Proteínas de Homeodomínio/metabolismo , Fatores de Transcrição/metabolismo
18.
J Exp Zool A Ecol Integr Physiol ; 337(7): 768-775, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35713191

RESUMO

Gammarus aequicauda is the most abundant amphipod species in the Crimean hypersaline lakes, and is predatory upon other invertebrate species, suppressing their populations. The authors studied a time balance during the feeding of G. aequicauda in the presence of two prey species. The different variants of prey composition were: (1) two Artemia sp., (2) two chironomid larvae, and (3) one Artemia sp. and one chironomid larva. The duration of the experiments differed and continued until both prey were consumed. The experiments were carried out in vessels with and without bottom sediments. The result showed that in vessels with and without sediments in the case of both species of prey, the time to the capture of the first prey did not depend on whether Artemia sp. or chironomid larva was the first prey; the time differences are statistically insignificant. The duration of eating prey in all experimental variants depended on the kind of prey, and those differences were highly significant. The average hourly consumption rate was dependent on prey composition and order of prey capture and eating. The maximum consumption for two prey was when both were brine shrimp. In vessels without sediments and containing both Artemia sp. and chironomid larva the consumption rate was higher if the first caught prey was Artemia sp. rather than сhironomid larva. The order of prey eating did not influence a ration size in vessels with bottom sediments. When both prey were chironomid larvae, the total diet did not practically differ in vessels with or without sediments.


Assuntos
Anfípodes , Chironomidae , Animais , Artemia , Comportamento Alimentar/fisiologia , Larva/fisiologia , Comportamento Predatório/fisiologia
19.
Bioorg Chem ; 124: 105832, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35500502

RESUMO

Thiosemicarbazides (TSCs), dithiocarbamates (DTCs) and their molecular conjugates are promising drug targets. However, hybrids of DTCs with TSCs themselves are rarely investigated. Thus, studies were initiated to synthesize novel system derived from TSC-DTCs to examine their pharmacological applications. The targeted conjugates were designed and synthesized from aryl TSC and aryl DTCs in moderate to good yields. The structures of synthesized compounds were confirmed through FT-IR, 1H NMR, 13C NMR and mass spectrometry. The conjugates have been tested for antioxidant and anticancer activities. The in vitro antioxidant activity was performed using 1,1-diphenyl-2-picryl hydrazyl (DPPH) free radical scavenging assay, hydrogen peroxide scavenging assay and nitric oxide assay and was also compared with aryl DTCs and aryl TSCs to explore potential of newly synthesized hybrids. The preliminary anticancer screening for cytotoxicity was performed using brine shrimp lethality bioassay using Artemia salina shrimps. Anticancer screening was determined against NCI60 human tumor cell lines at NCI, USA. The results revealed that, newly synthesized hybrids are more active as compared to aryl DTCs and aryl TSCs. Among the tested conjugates for antioxidant screening, 3b was found to be more active than the standard ascorbic acid. The IC50 value of 3b were 8.96 ± 0.089, 10.7 ± 0.016 and 12.29 ± 0.086 µg/ml for DPPH, hydrogen peroxide scavenging assay and nitric oxide assay respectively, whereas IC50 values for standard were 11.75 ± 0.015, 12.03 ± 0.107 and 16.66 ± 0.242 µg/ml respectively. Since hybrids are more active than aryl DTCs and aryl TSCs, only newly synthesized hybrids were screened for anticancer potential. For cytotoxicity screening, compound 3b was found to be most active among synthesized conjugates with LD50 value of 33.86 µg/ml. For anticancer screening, the compounds 3c and 3d were found to be potent among synthesized series with percent growth inhibition of 22 to 44% when screened against colon cancer cell lines whereas, compound 3b showed growth inhibition of 40% for selective leukemia cell line, K-562. The compounds 3b, 3c and 3d with strong electron-withdrawing groups were found to be the most active antioxidant and anticancer agents among the synthesized conjugates.


Assuntos
Antineoplásicos , Antioxidantes , Animais , Antineoplásicos/química , Antineoplásicos/farmacologia , Antioxidantes/química , Antioxidantes/farmacologia , Artemia , Linhagem Celular Tumoral , Proliferação de Células , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Peróxido de Hidrogênio/farmacologia , Óxido Nítrico/farmacologia , Semicarbazidas , Espectroscopia de Infravermelho com Transformada de Fourier
20.
Toxins (Basel) ; 14(5)2022 04 28.
Artigo em Inglês | MEDLINE | ID: mdl-35622559

RESUMO

Phlorotannins have been proven to contain numerous bioactive compounds that have potential to be applied in variety industries, including cosmetics, functional foods, nutraceuticals, environmental management, and medicine. The larvicidal and growth-inhibiting properties of phlorotannins have been extensively studied in various organisms. However, the toxicity of the phloroglucinol oligomer of phlorotannin is unclear, especially in Artemia salina, Daphnia magna, Lactuca sativa, and Chlorella vulgaris, which are commonly used in many bioassays. Therefore, research using these four organisms should be designed to provide basic information about the toxic effects of phlorotannins and phloroglucinol. This study aimed to evaluate the larvicidal and inhibitory properties of phlorotannins and phloroglucinol on A. salina, D. magna, L. sativa, and C. vulgaris. Phlorotannin extract and phloroglucinol were administered at various concentrations to each test organism. The survival rate of A. salina nauplii and D. magna neonates was observed every 24 h to 72 h, whereas the L. sativa seed germination and inhibition rate of C. vulgaris were observed up to 96 h. The results showed that the 24 h LC50 of phlorotannin on A. salina and D. magna were 10.67 and 1.32 mg/mL, respectively. The germination inhibition of L. sativa was 53.3% with a seed growth of less than 4 mm after 96 h upon exposure to 1 mg/mL of phlorotannin. Freshwater and seawater C. vulgaris experienced yield inhibition of 39.47 and 43.46%, respectively, when 2 mg/mL of phlorotanin was added. These results indicate that phlorotannin affects the survival and growth of the test organisms, so its use as a pesticide, herbicide, and algaecide agent for environmental and aquaculture applications can be further studied.


Assuntos
Artrópodes , Chlorella vulgaris , Herbicidas , Animais , Aquicultura , Artemia , Floroglucinol/toxicidade
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