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1.
Genes (Basel) ; 14(9)2023 08 24.
Artigo em Inglês | MEDLINE | ID: mdl-37761811

RESUMO

Genetic diversity and population structuring for the species Haemogogus leucocelaenus, a sylvatic vector of yellow fever virus, were found to vary with the degree of agricultural land use and isolation of fragments of Atlantic Forest in municipalities in the state of São Paulo where specimens were collected. Genotyping of 115 mitochondrial SNPs showed that the populations with the highest indices of genetic diversity (polymorphic loci and mean pairwise differences between the sequences) are found in areas with high levels of agricultural land use (northeast of the State). Most populations exhibited statistically significant negative values for the Tajima D and Fu FS neutrality tests, suggesting recent expansion. The results show an association between genetic diversity in this species and the degree of agricultural land use in the sampled sites, as well as signs of population expansion of this species in most areas, particularly those with the highest forest edge densities. A clear association between population structuring and the distance between the sampled fragments (isolation by distance) was observed: samples from a large fragment of Atlantic Forest extending along the coast of the state of São Paulo exhibited greater similarity with each other than with populations in the northwest of the state.


Assuntos
Culicidae , Febre Amarela , Animais , Febre Amarela/genética , Brasil , Mosquitos Vetores/genética , Florestas
2.
Int J Mol Sci ; 24(13)2023 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-37445595

RESUMO

There is evidence that IL-22 and IL-17 participate in the pathogenesis of allergic asthma. To investigate the role of IL-22, we used IL-22 deficient mice (IL-22 KO) sensitized and challenged with ovalbumin (OVA) and compared with wild type (WT) animals exposed to OVA. IL-22 KO animals exposed to OVA showed a decreased number and frequency of eosinophils, IL-5 and IL-13 in the airways, reduced mucus production and pulmonary inflammation. In addition, IL-22 KO animals exhibited a decreased percentage and number of lung CD11c+CD11b+ cells and increased apoptosis of eosinophils. Th17 cell transfer generated from IL-22 KO to animals previously sensitized and challenged with OVA caused a reduction in eosinophil frequency and number in the airways compared to animals transferred with Th17 cells generated from WT mice. Therefore, IL-22 is deleterious with concomitant secretion of IL-17. Our findings show a pro-inflammatory role for IL-22, confirmed in a model of allergen-free and allergen-specific immunotherapy. Moreover, during the comorbidity asthma and pneumonia that induces neutrophil inflammation, IL-22 was not detrimental. Our results show that targeting IL-22 would negatively affect the survival of eosinophils, reduce the expansion or migration of CD11c+CD11b+ cells, and negatively regulate allergic asthma.


Assuntos
Asma , Pneumonia , Camundongos , Animais , Interleucina-17/genética , Asma/patologia , Pulmão/patologia , Eosinófilos , Pneumonia/patologia , Alérgenos , Comorbidade , Ovalbumina , Modelos Animais de Doenças , Líquido da Lavagem Broncoalveolar , Camundongos Endogâmicos BALB C
3.
Microorganisms ; 11(5)2023 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-37317119

RESUMO

Anopheles darlingi is a major malaria vector in the Amazon region and, like other vectors, harbors a community of microorganisms with which it shares a network of interactions. Here, we describe the diversity and bacterial composition from the midguts and salivary glands of lab-reared and field-captured An. darlingi using metagenome sequencing of the 16S rRNA gene. The libraries were built using the amplification of the region V3-V4 16S rRNA gene. The bacterial community from the salivary glands was more diverse and richer than the community from the midguts. However, the salivary glands and midguts only showed dissimilarities in beta diversity between lab-reared mosquitoes. Despite that, intra-variability was observed in the samples. Acinetobacter and Pseudomonas were dominant in the tissues of lab-reared mosquitoes. Sequences of Wolbachia and Asaia were both found in the tissue of lab-reared mosquitoes; however, only Asaia was found in field-captured An. darlingi, but in low abundance. This is the first report on the characterization of microbiota composition from the salivary glands of An. darlingi from lab-reared and field-captured individuals. This study can provide invaluable insights for future investigations regarding mosquito development and interaction between mosquito microbiota and Plasmodium sp.

4.
Biomolecules ; 13(3)2023 03 17.
Artigo em Inglês | MEDLINE | ID: mdl-36979487

RESUMO

Mosquito females of the genus Mansonia (Blanchard) can be a nuisance to humans and animals since they are voraciously hematophagous and feed on the blood of a variety of vertebrates. Despite their relevance, there is a lack of investigation into the blood-feeding patterns of the Mansonia species. Knowledge of the host preference is crucial in establishing the public health importance of a mosquito species and its potential to be involved in the transmission dynamics of pathogens. Species that are primarily anthropophilic can be more effective in spreading vector-borne pathogens to humans. In this study, we used an Illumina Nextera sequencing protocol and the QIIME2 workflow to assess the diversity of DNA sequences extracted in the ingested blood of mosquito species to evaluate the overall and local host choices for three species: Ma. titillans, Ma. Amazonensis, and Ma. humeralis, in rural areas alongside the Madeira River in the vicinities of the Santo Antonio Energia (SAE) reservoir in the municipality of Porto Velho, Rondônia, Western Brazil. By performing our analysis pipeline, we have found that host diversity per collection site showed a significant heterogeneity across the sample sites. In addition, in rural areas, Ma. amazonensis present a high affinity for B. taurus, Ma. humeralis shows an overall preference for C. familiaris and B. taurus, but also H. sapiens and E. caballus in urban areas, and Ma. titillans showed more opportunistic behavior in rural areas, feeding on wild animals and G. gallus, though with an overall preference for H. sapiens.


Assuntos
Culicidae , Humanos , Animais , Feminino , Brasil , Mosquitos Vetores , Comportamento Alimentar , Saúde Pública
5.
Microorganisms ; 10(7)2022 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-35889116

RESUMO

The quality of aquatic ecosystems is a major public health concern. The assessment and management of a freshwater system and the ecological monitoring of microorganisms that are present in it can provide indicators of the environment and water quality to protect human and animal health. with bacteria is. It is a major challenge to monitor the microbiological bacterial contamination status of surface water associated with anthropogenic activities within rivers and freshwater reservoirs. Understanding the composition of aquatic microbial communities can be beneficial for the early detection of pathogens, improving our knowledge of their ecological niches, and characterizing the assemblages of microbiota responsible for the degradation of contaminants and microbial substrates. The present study aimed to characterize the bacterial microbiota of water samples collected alongside the Madeira River and its small tributaries in rural areas near the Santo Antonio Energia hydroelectric power plant (SAE) reservoir in the municipality of Porto Velho, Rondonia state, Western Brazil. An Illumina 16s rRNA metagenomic approach was employed and the physicochemical characteristics of the water sample were assessed. We hypothesized that both water metagenomics and physicochemical parameters would vary across sampling sites. The most abundant genera found in the study were Acinetobacter, Deinococcus, and Pseudomonas. PERMANOVA and ANCOM analysis revealed that collection points sampled at the G4 location presented a significantly different microbiome compared to any other group, with the Chlamidomonadaceae family and Enhydrobacter genus being significantly more abundant. Our findings support the use of metagenomics to assess water quality standards for the protection of human and animal health in this microgeographic region.

6.
Infect Genet Evol ; 103: 105341, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35878819

RESUMO

In high abundance, females of the genus Mansonia (Blanchard) can be a nuisance to humans and animals because they are voraciously hematophagous and feed on the blood of a myriad of vertebrates. The spatial-temporal distribution pattern of Mansonia species is associated with the presence of their host plants, usually Eichhornia crassipes, E. azurea, Ceratopteris pteridoides, Limnobium laevigatum, Pistia stratiotes, and Salvinia sp. Despite their importance, there is a lack of investigation on the dispersion and population genetics of Mansonia species. Such studies are pivotal to evaluating the genetic structuring, which ultimately reflects populational expansion-retraction patterns and dispersal dynamics of the mosquito, particularly in areas with a history of recent introduction and establishment. The knowledge obtained could lead to better understanding of how anthropogenic changes to the environment can modulate the population structure of Mansonia species, which in turn impacts mosquito population density, disturbance to humans and domestic animals, and putative vector-borne disease transmission patterns. In this study, we present an Illumina NGS sequencing protocol to obtain whole-mitogenome sequences of Mansonia spp. to assess the microgeographic genetic diversity and dispersion of field-collected adults. The specimens were collected in rural environments in the vicinities of the Santo Antônio Energia (SAE) hydroelectric reservoir on the Madeira River.


Assuntos
Ascaridídios , Culicidae , Malvaceae , Adulto , Animais , Brasil/epidemiologia , Feminino , Genética Populacional , Humanos , Mitocôndrias , Mosquitos Vetores , Rios
7.
BMC Genomics ; 23(1): 282, 2022 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-35395723

RESUMO

BACKGROUND: Bees are the most important group of pollinators worldwide and their populations are declining. In natural conditions, Apis mellifera depends exclusively on food from the field to meet its physiological demands. In the period of scarcity, available resources are insufficient and artificial supplementation becomes essential for maintaining the levels of vitamins, proteins, carbohydrates, and minerals of colonies. Among these minerals, zinc is essential in all living systems, particularly for the regulation of cell division and protein synthesis, and is a component of more than 200 metalloenzymes. RESULTS: The total RNA extracted from the brain tissue of nurse bees exposed to different sources and concentrations of zinc was sequenced. A total of 1,172 genes in the treatment that received an inorganic source of zinc and 502 genes that received an organic source of zinc were found to be differentially expressed among the control group. Gene ontology enrichment showed that zinc can modulate important biological processes such as nutrient metabolism and the molting process. CONCLUSIONS: Our results indicate that zinc supplementation modulates the expression of many differentially expressed genes and plays an important role in the development of Apis mellifera bees. All the information obtained in this study can contribute to future research in the field of bee nutrigenomics.


Assuntos
Transcriptoma , Zinco , Animais , Abelhas/genética , Encéfalo , Suplementos Nutricionais , Nutrigenômica , Zinco/farmacologia
8.
Parasit Vectors ; 15(1): 106, 2022 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-35346342

RESUMO

BACKGROUND: In Brazil, malaria is concentrated in the Amazon Basin, where more than 99% of the annual cases are reported. The main goal of this study was to investigate the population structure and genetic association of the biting behavior of Nyssorhynchus (also known as Anopheles) darlingi, the major malaria vector in the Amazon region of Brazil, using low-coverage genomic sequencing data. METHODS: Samples were collected in the municipality of Mâncio Lima, Acre state, Brazil between 2016 and 2017. Different approaches using genotype imputation and no gene imputation for data treatment and low-coverage sequencing genotyping were performed. After the samples were genotyped, population stratification analysis was performed. RESULTS: Weak but statistically significant stratification signatures were identified between subpopulations separated by distances of approximately 2-3 km. Genome-wide association studies (GWAS) were performed to compare indoor/outdoor biting behavior and blood-seeking at dusk/dawn. A statistically significant association was observed between biting behavior and single nucleotide polymorphism (SNP) markers adjacent to the gene associated with cytochrome P450 (CYP) 4H14, which is associated with insecticide resistance. A statistically significant association between blood-seeking periodicity and SNP markers adjacent to genes associated with the circadian cycle was also observed. CONCLUSION: The data presented here suggest that low-coverage whole-genome sequencing with adequate processing is a powerful tool to genetically characterize vector populations at a microgeographic scale in malaria transmission areas, as well as for use in GWAS. Female mosquitoes entering houses to take a blood meal may be related to a specific CYP4H14 allele, and female timing of blood-seeking is related to circadian rhythm genes.


Assuntos
Anopheles , Malária , Animais , Anopheles/genética , Vetores de Doenças , Feminino , Estudo de Associação Genômica Ampla , Mosquitos Vetores/genética
9.
Genes (Basel) ; 12(11)2021 10 25.
Artigo em Inglês | MEDLINE | ID: mdl-34828299

RESUMO

Mosquito susceptibility to Plasmodium spp. infection is of paramount importance for malaria occurrence and sustainable transmission. Therefore, understanding the genetic features underlying the mechanisms of susceptibility traits is pivotal to assessing malaria transmission dynamics in endemic areas. The aim of this study was to investigate the susceptibility of Nyssorhynchus darlingi-the dominant malaria vector in Brazil-to Plasmodium spp. using a reduced representation genome-sequencing protocol. The investigation was performed using a genome-wide association study (GWAS) to identify mosquito genes that are predicted to modulate the susceptibility of natural populations of the mosquito to Plasmodium infection. After applying the sequence alignment protocol, we generated the variant panel and filtered variants; leading to the detection of 202,837 SNPs in all specimens analyzed. The resulting panel was used to perform GWAS by comparing the pool of SNP variants present in Ny. darlingi infected with Plasmodium spp. with the pool obtained in field-collected mosquitoes with no evidence of infection by the parasite (all mosquitoes were tested separately using RT-PCR). The GWAS results for infection status showed two statistically significant variants adjacent to important genes that can be associated with susceptibility to Plasmodium infection: Cytochrome P450 (cyp450) and chitinase. This study provides relevant knowledge on malaria transmission dynamics by using a genomic approach to identify mosquito genes associated with susceptibility to Plasmodium infection in Ny. darlingi in western Amazonian Brazil.


Assuntos
Anopheles , Malária/genética , Plasmodium/patogenicidade , Animais , Anopheles/genética , Anopheles/parasitologia , Brasil , Suscetibilidade a Doenças , Vetores de Doenças , Feminino , Genética Populacional , Estudo de Associação Genômica Ampla/veterinária , Biblioteca Genômica , Interações Hospedeiro-Parasita/genética , Malária/parasitologia , Malária/transmissão , Mosquitos Vetores/genética , Mosquitos Vetores/parasitologia , Polimorfismo de Nucleotídeo Único
10.
Artigo em Inglês | MEDLINE | ID: mdl-34495263

RESUMO

Trachoma is a keratoconjunctivitis caused by Chlamydia trachomatis, considered an important leading cause of preventable blindness in the world. This study aimed at verifying if flies can be the vectors for trachoma in our municipality. Flies were assessed in the households of children diagnosed with inflammatory trachoma at the municipality of Botucatu, Sao Paulo State, Brazil. Fly traps were placed in the backyard of the houses during 24 h, in each of the four weather seasons, over a period of one year. The collected dipterans were taxonomically classified and the presence of Chlamydia trachomatis in the flies was evidenced by using the Polymerase Chain Reaction (PCR). During the studied period, 2,188 flies were collected, mainly during the summer and the spring. The most common identified fly was Musca domestica. All fly samples were negative for Chlamydia trachomatis but several other different bacteria were identified in these flies. The authors concluded that flies are probably not the vectors for trachoma in the studied area. Further studies should be conducted to evaluate other possible factors responsible for the maintenance of the disease in our environment.


Assuntos
Dípteros , Gonorreia , Tracoma , Animais , Brasil/epidemiologia , Chlamydia trachomatis/genética , Tracoma/epidemiologia
11.
Cells ; 10(7)2021 07 08.
Artigo em Inglês | MEDLINE | ID: mdl-34359902

RESUMO

The microbiota of the gut-lung axis affects local and far-reaching immune responses and might also trigger chronic and inflammatory diseases. We hypothesized that gut dysbiosis induced by obesity, which coexists in countries with a high tuberculosis burden, aggravates the host susceptibility and the pulmonary damage tolerance. To assess our hypothesis, we used a model of high-fat diet (HFD)-induced obesity, followed by infection of C57BL/6 mice with Mycobacterium tuberculosis. We showed that obesity increased the susceptibility, the pulmonary inflammation and IFN-γ levels in M. tuberculosis-infected mice. During the comorbidity obesity and tuberculosis, there is an increase of Bacteroidetes and Firmicutes in the lungs, and an increase of Firmicutes and butyrate in the feces. Depletion of gut microbiota by antibiotic treatment in the obese infected mice reduced the frequencies of CD4+IFN-γ+IL-17- cells and IFN-γ levels in the lungs, associated with an increase of Lactobacillus. Our findings reinforce the role of the gut-lung axis in chronic infections and suggest that the gut microbiota modulation may be a potential host-directed therapy as an adjuvant to treat TB in the context of IFN-γ-mediated immunopathology.


Assuntos
Disbiose/etiologia , Disbiose/microbiologia , Interferon gama/biossíntese , Obesidade/complicações , Obesidade/microbiologia , Pneumonia/microbiologia , Tuberculose/complicações , Imunidade Adaptativa , Animais , Carga Bacteriana , Suscetibilidade a Doenças , Disbiose/imunologia , Transplante de Microbiota Fecal , Fezes/microbiologia , Feminino , Leucócitos/metabolismo , Pulmão/imunologia , Pulmão/microbiologia , Pulmão/patologia , Camundongos Endogâmicos C57BL , Microbiota , Obesidade/imunologia , Pneumonia/imunologia , Tuberculose/imunologia
12.
An Acad Bras Cienc ; 93(2): e20200452, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34076039

RESUMO

Microsatellite primers pairs were developed for the Neotropical tree Roupala montana var. brasiliensis for use in studies on genetic diversity, mating system, and gene flow. Forty-two primer pairs were developed, resulting in 27 polymorphic loci, with two to 27 alleles per locus. The primer pairs were validated against 34 R. montana var. brasiliensis adult trees from four populations. The observed (H o) and expected (H e)heterozygosities ranged among loci from 0.061 to 0.930 (mean of 0.544) and from 0.116 to 0.950 (mean of 0.700), respectively. Null alleles were observed for ten loci. No genotypic linkage disequilibrium was detected in any pair of loci. This set of loci is suitable for population genetic studies of the species.


Assuntos
Repetições de Microssatélites , Proteaceae/genética , Genética Populacional , Genótipo , Polimorfismo Genético
13.
PLoS One ; 16(4): e0246215, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33831004

RESUMO

Vale do Rio Juruá in western Acre, Brazil, is a persistent malaria transmission hotspot partly due to fish farming development that was encouraged to improve local standards of living. Fish ponds can be productive breeding sites for Amazonian malaria vector species, including Nyssorhynchus darlingi, which, combined with high human density and mobility, add to the local malaria burden.This study reports entomological profile of immature and adult Ny. darlingi at three sites in Mâncio Lima, Acre, during the rainy and dry season (February to September, 2017). From 63 fishponds, 10,859 larvae were collected, including 5,512 first-instar Anophelinae larvae and 4,927 second, third and fourth-instars, of which 8.5% (n = 420) were Ny. darlingi. This species was most abundant in not-abandoned fishponds and in the presence of emerging aquatic vegetation. Seasonal analysis of immatures in urban landscapes found no significant difference in the numbers of Ny. darlingi, corresponding to equivalent population density during the rainy to dry transition period. However, in the rural landscape, significantly higher numbers of Ny. darlingi larvae were collected in August (IRR = 5.80, p = 0.037) and September (IRR = 6.62, p = 0.023) (dry season), compared to February (rainy season), suggesting important role of fishponds for vector population maintenance during the seasonal transition in this landscape type. Adult sampling detected mainly Ny. darlingi (~93%), with similar outdoor feeding behavior, but different abundance according to landscape profile: urban site 1 showed higher peaks of human biting rate in May (46 bites/person/hour), than February (4) and September (15), while rural site 3 shows similar HBR during the same sampling period (22, 24 and 21, respectively). This study contributes to a better understanding of the larvae biology of the main malaria vector in the Vale do Rio Juruá region and, ultimately will support vector control efforts.


Assuntos
Anopheles/fisiologia , Aquicultura , Malária , Mosquitos Vetores/fisiologia , Lagoas , Estações do Ano , Animais , Brasil , Larva/fisiologia , Dinâmica Populacional
14.
mBio ; 12(2)2021 03 30.
Artigo em Inglês | MEDLINE | ID: mdl-33785632

RESUMO

The mosquito microbiota is composed of several lineages of microorganisms whose ecological roles and evolutionary histories have yet to be investigated in depth. Among these microorganisms, Asaia bacteria play a prominent role, given their abundance in the gut, reproductive organs, and salivary glands of different mosquito species, while their presence has also been reported in several other insects. Notably, Asaia has great potential as a tool for the control of mosquito-borne diseases. Here, we present a wide phylogenomic analysis of Asaia strains isolated from different species of mosquito vectors and from different populations of the Mediterranean fruit fly (medfly), Ceratitis capitata, an insect pest of worldwide economic importance. We show that phylogenetically distant lineages of Asaia experienced independent genome reductions, despite following a common pattern, characterized by the early loss of genes involved in genome stability. This result highlights the role of specific metabolic pathways in the symbiotic relationship between Asaia and the insect host. Finally, we discovered that all but one of the Asaia strains included in the study possess the pyrethroid hydrolase gene. Phylogenetic analysis revealed that this gene is ancestral in Asaia, strongly suggesting that it played a role in the establishment of the symbiotic association between these bacteria and the mosquito hosts. We propose that this gene from the symbiont contributed to initial pyrethroid resistance in insects harboring Asaia, also considering the widespread production of pyrethrins by several plants.IMPORTANCE We have studied genome reduction within several strains of the insect symbiont Asaia isolated from different species/strains of mosquito and medfly. Phylogenetically distant strains of Asaia, despite following a common pattern involving the loss of genes related to genome stability, have undergone independent genome reductions, highlighting the peculiar role of specific metabolic pathways in the symbiotic relationship between Asaia and its host. We also show that the pyrethroid hydrolase gene is present in all the Asaia strains isolated except for the South American malaria vector Anopheles darlingi, for which resistance to pyrethroids has never been reported, suggesting a possible involvement of Asaia in determining resistance to insecticides.


Assuntos
Acetobacteraceae/genética , Proteínas de Bactérias/metabolismo , Ceratitis capitata/microbiologia , Culicidae/microbiologia , Genoma Bacteriano , Filogenia , Simbiose , Acetobacteraceae/classificação , Acetobacteraceae/isolamento & purificação , Acetobacteraceae/fisiologia , Animais , Proteínas de Bactérias/genética , Ceratitis capitata/efeitos dos fármacos , Ceratitis capitata/fisiologia , Culicidae/efeitos dos fármacos , Culicidae/fisiologia , Evolução Molecular , Tamanho do Genoma , Resistência a Inseticidas , Inseticidas/farmacologia , Masculino , Piretrinas/farmacologia
15.
Sci Rep ; 10(1): 22190, 2020 12 17.
Artigo em Inglês | MEDLINE | ID: mdl-33335128

RESUMO

Multiple sclerosis is an autoimmune disease that affects the myelinated central nervous system (CNS) neurons and triggers physical and cognitive disabilities. Conventional therapy is based on disease-modifying drugs that control disease severity but can also be deleterious. Complementary medicines have been adopted and evidence indicates that yeast supplements can improve symptoms mainly by modulating the immune response. In this investigation, we evaluated the therapeutic potential of Saccharomyces cerevisiae and its selenized derivative (Selemax) in experimental autoimmune encephalomyelitis (EAE). Female C57BL/6 mice submitted to EAE induction were orally supplemented with these yeasts by gavage from day 0 to day 14 after EAE induction. Both supplements determined significant reduction in clinical signs concomitantly with diminished Th1 immune response in CNS, increased proportion of Foxp3+ lymphocytes in inguinal and mesenteric lymph nodes and increased microbiota diversity. However, Selemax was more effective clinically and immunologically; it reduced disease prevalence more sharply, increased the proportion of CD103+ dendritic cells expressing high levels of PD-L1 in mesenteric lymph nodes and reduced the intestinal inflammatory process more strongly than S. cerevisiae. These results suggest a clear gut-brain axis modulation by selenized S. cerevisiae and suggest their inclusion in clinical trials.


Assuntos
Suplementos Nutricionais , Encefalomielite Autoimune Experimental/etiologia , Encefalomielite Autoimune Experimental/metabolismo , Imunomodulação , Mucosa Intestinal/imunologia , Mucosa Intestinal/metabolismo , Saccharomyces cerevisiae/imunologia , Animais , Sistema Nervoso Central/imunologia , Sistema Nervoso Central/metabolismo , Sistema Nervoso Central/patologia , Suscetibilidade a Doenças , Encefalomielite Autoimune Experimental/patologia , Tolerância Imunológica , Contagem de Linfócitos , Camundongos , Subpopulações de Linfócitos T/imunologia , Subpopulações de Linfócitos T/metabolismo
16.
J Venom Anim Toxins Incl Trop Dis ; 26: e20200004, 2020 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-32518557

RESUMO

BACKGROUND: The nutritional requirements of honeybees (Apis mellifera) for their complete development need to be supplied through food sources available in the environment, since honeybees are insects that depend directly on blossoming food sources. However, at certain times a food-supply reduction can promote nutritional stress, thus necessitating food supplementation for maintenance or production stimulus of the colonies. Thus, the determination of optimal energy supplementation can assist in the maintenance and production of colonies. METHODS: Twenty Apis mellifera beehives were used (with five beehives per treatment): CTL, control (without feeding); SJ, sugarcane juice; SS, sugar syrup; and IS, inverted sucrose. We evaluated the food consumption, population development, and physiological state (expression of vitellogenin and hexamerin 70a genes) of each colony. RESULTS: The results showed that the supplementation of colonies with sugar syrup resulted in an intermediate consumption level (894.6 ± 291 mL) and better development (384.9 ± 237.3 and 158.3 ± 171.6 cm2, sealed and open brood, respectively). Furthermore, this diet ensured that the colonies were in a good physiological state, as bees fed this diet presented the highest relative expression levels of vitellogenin and hexamerin 70a among all the diets tested. CONCLUSIONS: Therefore, sugar syrup is concluded to be the best artificial energetic food for use in the supplementation of honeybee colonies.

17.
Mol Phylogenet Evol ; 151: 106896, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32562821

RESUMO

The reconstruction of relationships within recently radiated groups is challenging even when massive amounts of sequencing data are available. The use of restriction site-associated DNA sequencing (RAD-Seq) to this end is promising. Here, we assessed the performance of RAD-Seq to infer the species-level phylogeny of the rapidly radiating genus Cereus (Cactaceae). To examine how the amount of genomic data affects resolution in this group, we used datasets and implemented different analyses. We sampled 52 individuals of Cereus, representing 18 of the 25 species currently recognized, plus members of the closely allied genera Cipocereus and Praecereus, and other 11 Cactaceae genera as outgroups. Three scenarios of permissiveness to missing data were carried out in iPyRAD, assembling datasets with 30% (333 loci), 45% (1440 loci), and 70% (6141 loci) of missing data. For each dataset, Maximum Likelihood (ML) trees were generated using two supermatrices, i.e., only SNPs and SNPs plus invariant sites. Accuracy and resolution were improved when the dataset with the highest number of loci was used (6141 loci), despite the high percentage of missing data included (70%). Coalescent trees estimated using SVDQuartets and ASTRAL are similar to those obtained by the ML reconstructions. Overall, we reconstruct a well-supported phylogeny of Cereus, which is resolved as monophyletic and composed of four main clades with high support in their internal relationships. Our findings also provide insights into the impact of missing data for phylogeny reconstruction using RAD loci.


Assuntos
Evolução Biológica , Cactaceae/genética , Genoma de Planta , Análise de Sequência de DNA , Sequência de Bases , Bases de Dados Genéticas , Loci Gênicos , Especiação Genética , Funções Verossimilhança , Filogenia , Polimorfismo de Nucleotídeo Único/genética , Análise de Componente Principal
18.
Mol Phylogenet Evol ; 142: 106642, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31605812

RESUMO

Hybridization and introgression between species in contact/hybrid zones provide important insight into the genetic and ecological mechanisms of speciation. Cactaceae represents the most important radiation of true succulent angiosperms in the New World. This diversification continues to date, with species experiencing few intrinsic barriers to gene flow and the frequent occurrence of natural hybridization. Here, we used RAD-Seq single-nucleotide polymorphism (SNP) data to investigate the genetic architecture of hybridization in four hybrid zones hosting Melocactus concinnus and four congeneric species (M. ernestii, M. glaucescens, M. paucispinus, and M. zehntneri). Our results revealed that M. concinnus is highly promiscuous in sympatric areas and hybridizes with various species distributed in Morro do Chapéu (Diamantina Plateau, Bahia), eastern Brazil. However, the contemporary genomic introgression among the investigated species is very low (c. 2-5%), confirming that even in the face of hybridization, Melocactus species maintain their genetic integrity. The genomic cline approach showed a large fraction of loci deviating from a model of neutral introgression, where most of the loci are consistent with selection favoring parental genotypes. Our results suggest the occurrence of weak premating but strong postmating reproductive isolation in the analyzed cactus species. Furthermore, as most of the Melocactus species are restricted in distribution, hybridization might negatively affect their integrity if hybrids replace the parental species.


Assuntos
Cactaceae/genética , Hibridização Genética , Brasil , Fluxo Gênico , Introgressão Genética , Polimorfismo de Nucleotídeo Único , Isolamento Reprodutivo , Simpatria
19.
J. venom. anim. toxins incl. trop. dis ; 26: e20200004, 2020. tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1135153

RESUMO

The nutritional requirements of honeybees (Apis mellifera) for their complete development need to be supplied through food sources available in the environment, since honeybees are insects that depend directly on blossoming food sources. However, at certain times a food-supply reduction can promote nutritional stress, thus necessitating food supplementation for maintenance or production stimulus of the colonies. Thus, the determination of optimal energy supplementation can assist in the maintenance and production of colonies. Methods: Twenty Apis mellifera beehives were used (with five beehives per treatment): CTL, control (without feeding); SJ, sugarcane juice; SS, sugar syrup; and IS, inverted sucrose. We evaluated the food consumption, population development, and physiological state (expression of vitellogenin and hexamerin 70a genes) of each colony. Results: The results showed that the supplementation of colonies with sugar syrup resulted in an intermediate consumption level (894.6 ± 291 mL) and better development (384.9 ± 237.3 and 158.3 ± 171.6 cm2, sealed and open brood, respectively). Furthermore, this diet ensured that the colonies were in a good physiological state, as bees fed this diet presented the highest relative expression levels of vitellogenin and hexamerin 70a among all the diets tested. Conclusions: Therefore, sugar syrup is concluded to be the best artificial energetic food for use in the supplementation of honeybee colonies.(AU)


Assuntos
Animais , Abelhas/crescimento & desenvolvimento , Expressão Gênica , Suplementos Nutricionais , Criação de Abelhas
20.
Sci Rep ; 9(1): 15492, 2019 10 29.
Artigo em Inglês | MEDLINE | ID: mdl-31664152

RESUMO

Aedes aegypti is the most synanthropic and anthropophilic mosquito of Culicidae. This species always cohabits with humans and is extremely opportunistic. Vector dispersal is directly related to the ability of the females on successfully finding a mate in a generally patchy urban scenario. In the present work, we investigate transcriptional changes in Ae. aegypti females during the courtship process and after mating. We observe a substantial alteration in gene expression triggered just upon contact with Ae. aegypti males, which in turn was not fully correlated to the changes triggered by the contact. After analysing shared significant differentially regulated genes between conspecific contact and insemination, the major part of the observed transcriptomic change triggered by contact is reversed after mating, indicating an intermediary situation between naive and mating conditions that we hypothesize to be crucial for mating success. Upon contact, several chemosensory related genes are repressed, especially odorant binding proteins. Most of these genes return to higher expression rates after mating. None of these genes are significantly regulated by the encounter of a different species, Aedes albopictus. The results presented here might be applied to an innovative control approach focusing on the semiochemical systems of mosquitoes in an effort to disrupt undesirable host-insect interaction to reduce the risk of pathogen transmission to humans.


Assuntos
Aedes/fisiologia , Perfilação da Expressão Gênica , Comportamento Sexual Animal , Animais , Feminino , Masculino , Mosquitos Vetores
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