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1.
J Invertebr Pathol ; 203: 108057, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38176675

RESUMO

Nitric oxide (NO) is a simple molecule involved in many biological processes and functions in the cardiovascular, neural, and immune systems. In recent years, NO has also been recognized as a crucial messenger in communication between the nervous and immune systems. Together with NO, catecholamines are the main group of neurotransmitters involved in cross-talk between the nervous and immune systems. Catecholamines such as noradrenaline, can act on immune cells through adrenoreceptors (ARs) present on the cell surface, and NO can cross the cell membrane and interact with secondary messengers, modulating catecholamine production. Here, we analyzed the mutual modulation by noradrenaline and NO in Phallusia nigra immune cells for specific subtypes of ARs. We also investigated the involvement of protein kinases A and C as secondary messengers to these specific subtypes of ARs in the adrenergic signaling pathway that culminates in NO modulation, and the phylogenetic distribution of ARs in deuterostome genomes. This analysis provided evidence for single-copy orthologs of α1, α2 and ß-AR in ascidian genomes, suggesting that NO and NA act on a less diverse set of ARs in urochordates. Pharmacological assays showed that high levels of NO can induce ascidian immune cells to produce catecholamines. We also observed that protein kinases A and C are the secondary messengers involved in downstream modulation of NO production through an ancestral ß-AR. Taken together, these results provide new information on NO as a modulator of immune cells, and reveal the molecules involved in the signaling pathway of ARs. The results also indicate that ARs may participate in NO modulation. Finally, our results suggest that the common ancestor of urochordates possessed a less complex system of ARs required for immune action and diverse pharmacological responses, since the α-ARs are phylogenetically more related to D1-receptors than are the ß-ARs.


Assuntos
Óxido Nítrico , Urocordados , Animais , Filogenia , Catecolaminas/metabolismo , Norepinefrina , Proteínas Quinases
2.
An Acad Bras Cienc ; 94(suppl 3): e20211361, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36417609

RESUMO

Since the first reported case of COVID-19 in Brazil, the public and private educational system started to close. Up to November 2020, scientific discussions about the return of schooling activities have been rarely performed by the national scientific community and police-makers. The great delay of school returning in Brazil contrasts with successful international strategies of school reopening worldwide and seems counterintuitive with the reopening of non-essential activities. Here, important issues to be considered before and during school reopening are reviewed and discussed. COVID-19 testing is essential to avoid disease spreading, but high cost of individual RT-qPCRs impairs an extensive testing strategy for school returning. To reduce costs and increase the speed of diagnosis, we tested the efficiency of a pooled-sample PCR strategy in a cohort of the educational staff in the city of Macaé/RJ, finding five asymptomatic individuals (0,66%) among the 754 people tested. Thus, a polled-sample PCR testing strategy of the educational staff might prevent infection spreading in schools at a reasonable cost. We discuss how our test strategy could be coupled with internationally recognized safety rules to allow for a safe school return and how countries from different world regions are dealing with educational activities during COVID-19 pandemic.


Assuntos
COVID-19 , Humanos , COVID-19/epidemiologia , Pandemias , Teste para COVID-19 , Brasil/epidemiologia , Instituições Acadêmicas
3.
Int J Mol Sci ; 23(19)2022 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-36232806

RESUMO

The SARS-CoV-2 virus infection led to millions of deaths during the COVID-19 pandemic. Hundreds of workers from several other Brazilian cities, as well as from other countries, arrive daily in Macaé to work in the oil supply chain, making this city a putative hotspot for the introduction of new viral lineages. In this study, we performed a genomic survey of SARS-CoV-2 samples from Macaé during the first outbreak of COVID-19, combined with clinical data and a molecular integrative analysis. First, phylogenomic analyses showed a high occurrence of viral introduction events and the establishment of local transmissions in Macaé, including the ingression and spread of the B.1.1.28 lineage in the municipality from June to August 2020. Second, SARS-CoV-2 mutations were identified in patients with distinct levels of COVID-19 severity. Third, molecular interactions of the mutated spike protein from three B.1.1.33 local samples and human ACE2 showed higher interactions than that of the wild-type spike protein from the ancestral virus. Altogether, these results elucidate the SARS-CoV-2 genomic profile in a strategic Brazilian city and further explore the functional aspects of SARS-CoV-2 with a characterization of emerging viral mutations associated with clinical data and the potential targets for drug development against SARS-CoV-2.


Assuntos
COVID-19 , SARS-CoV-2 , Enzima de Conversão de Angiotensina 2 , Brasil/epidemiologia , COVID-19/epidemiologia , Genômica , Humanos , Mutação , Pandemias , Filogenia , SARS-CoV-2/genética , Glicoproteína da Espícula de Coronavírus/genética
4.
Fish Shellfish Immunol ; 109: 41-50, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33285170

RESUMO

Dopamine (DA) is an important molecule that plays a role in the nervous and immune systems. DA is produced by a wide variety of animals and it is considered one of the oldest neurotransmitters. However, its specific function in immune cells has not been completely revealed. In a group of chordate animals, the ascidians, DA is reported to be produced by cells in the central nervous system (CNS); however, no dopaminergic receptor in their genomes has been described until now. Because this is an integrating characteristic of the ascidian dopamine system, here it was investigated the pharmacology, function, and phylogeny of DA and dopaminergic receptors (DRs) in the modulation of nitric oxide (NO) in the Phallusia nigra immune cells. The data disclosed, for the first time, that DA modulates NO production by immune cells. Its modulation probably occurs though adrenergic receptors, which display a special characteristic, in that they are capable of binding to noradrenaline (NA) and DA. A pharmacological analysis revealed that receptors present on the ascidian immune cells showed a high affinity to butaclamol, a non-selective D2-class receptor, increasing NO production. In addition, calcium intracellular mobilization was observed when DA was added to immune cells. In conclusion, the data revealed novel insights about the presence of catecholaminergic receptors (CRs) on the P. nigra immune cells, indicating that ascidian CRs have special pharmacological characteristics that are worth highlighting from an evolutionary point of view.


Assuntos
Dopamina/farmacologia , Neurotransmissores/farmacologia , Receptores de Dopamina D2/metabolismo , Transdução de Sinais/efeitos dos fármacos , Urocordados/imunologia , Animais , Dopamina/metabolismo , Filogenia
5.
Parasitology ; 148(8): 934-946, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33827719

RESUMO

Trichomonas vaginalis is a parasite of the human urogenital tract and the causative agent of trichomoniasis, a sexually transmitted disease of worldwide importance. This parasite is usually found as a motile flagellated trophozoite. However, when subjected to stressful microenvironmental conditions, T. vaginalis trophozoites can differentiate into peculiar cyst-like stages, which exhibit notable physiological resistance to unfavourable conditions. Although well documented in morphological and proteomic terms, patterns of gene expression changes involved in the cellular differentiation into cyst-like stages are mostly unknown. The real-time reverse transcription polymerase chain reaction (RT-qPCR) is recognized as a sensitive and accurate method for quantification of gene expression, providing fluorescence-based data that are proportional to the amount of a target RNA. However, the reliability of relative expression studies depends on the validation of suitable reference genes, which RNAs exhibit a minimum of variation between tested conditions. Here, we attempt to determine suitable reference genes to be used as controls of invariant expression during cold-induced in vitro differentiation of T. vaginalis trophozoites into cyst-like forms. Furthermore, we reveal that the mRNA from the meiotic recombinase Dmc1 is upregulated during this process, indicating that cryptic sexual events may take place in cyst-like stages of T. vaginalis.


Assuntos
Regulação da Expressão Gênica no Desenvolvimento/genética , Meiose/genética , Trichomonas vaginalis/crescimento & desenvolvimento , Trichomonas vaginalis/genética , Proteínas de Ciclo Celular/genética , Temperatura Baixa , Proteínas de Ligação a DNA/genética , Humanos , RNA Mensageiro/metabolismo , Valores de Referência , Regulação para Cima
6.
PLoS Genet ; 13(7): e1006868, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28671979

RESUMO

Gene regulatory networks (GRNs) evolve as a result of the coevolutionary processes acting on transcription factors (TFs) and the cis-regulatory modules they bind. The zinc-finger TF zelda (zld) is essential for the maternal-to-zygotic transition (MZT) in Drosophila melanogaster, where it directly binds over thousand cis-regulatory modules to regulate chromatin accessibility. D. melanogaster displays a long germ type of embryonic development, where all segments are simultaneously generated along the whole egg. However, it remains unclear if zld is also involved in the MZT of short-germ insects (including those from basal lineages) or in other biological processes. Here we show that zld is an innovation of the Pancrustacea lineage, being absent in more distant arthropods (e.g. chelicerates) and other organisms. To better understand zld´s ancestral function, we thoroughly investigated its roles in a short-germ beetle, Tribolium castaneum, using molecular biology and computational approaches. Our results demonstrate roles for zld not only during the MZT, but also in posterior segmentation and patterning of imaginal disc derived structures. Further, we also demonstrate that zld is critical for posterior segmentation in the hemipteran Rhodnius prolixus, indicating this function predates the origin of holometabolous insects and was subsequently lost in long-germ insects. Our results unveil new roles of zld in different biological contexts and suggest that changes in expression of zld (and probably other major TFs) are critical in the evolution of insect GRNs.


Assuntos
Proteínas de Drosophila/genética , Desenvolvimento Embrionário/genética , Evolução Molecular , Redes Reguladoras de Genes/genética , Fatores de Transcrição/genética , Animais , Padronização Corporal/genética , Besouros/genética , Proteínas de Drosophila/biossíntese , Drosophila melanogaster/genética , Drosophila melanogaster/crescimento & desenvolvimento , Regulação da Expressão Gênica no Desenvolvimento , Proteínas Nucleares , Regiões Promotoras Genéticas , Interferência de RNA , Fatores de Transcrição/biossíntese , Ativação Transcricional/genética , Asas de Animais/crescimento & desenvolvimento
7.
BMC Biol ; 15(1): 62, 2017 07 31.
Artigo em Inglês | MEDLINE | ID: mdl-28756775

RESUMO

BACKGROUND: The duplication of genes can occur through various mechanisms and is thought to make a major contribution to the evolutionary diversification of organisms. There is increasing evidence for a large-scale duplication of genes in some chelicerate lineages including two rounds of whole genome duplication (WGD) in horseshoe crabs. To investigate this further, we sequenced and analyzed the genome of the common house spider Parasteatoda tepidariorum. RESULTS: We found pervasive duplication of both coding and non-coding genes in this spider, including two clusters of Hox genes. Analysis of synteny conservation across the P. tepidariorum genome suggests that there has been an ancient WGD in spiders. Comparison with the genomes of other chelicerates, including that of the newly sequenced bark scorpion Centruroides sculpturatus, suggests that this event occurred in the common ancestor of spiders and scorpions, and is probably independent of the WGDs in horseshoe crabs. Furthermore, characterization of the sequence and expression of the Hox paralogs in P. tepidariorum suggests that many have been subject to neo-functionalization and/or sub-functionalization since their duplication. CONCLUSIONS: Our results reveal that spiders and scorpions are likely the descendants of a polyploid ancestor that lived more than 450 MYA. Given the extensive morphological diversity and ecological adaptations found among these animals, rivaling those of vertebrates, our study of the ancient WGD event in Arachnopulmonata provides a new comparative platform to explore common and divergent evolutionary outcomes of polyploidization events across eukaryotes.


Assuntos
Evolução Molecular , Duplicação Gênica , Genoma , Aranhas/genética , Animais , Feminino , Masculino , Sintenia
8.
Genesis ; 55(5)2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-28432816

RESUMO

The hemiptera Rhodnius prolixus is a blood-feeding insect and a primary vector of Trypanosoma cruzi, the etiological agent of the Chagas disease. Over the past century, Rhodnius has been the subject of intense investigations, which have contributed to unveil important aspects of metabolism and physiology in insects. Recent technological innovations are helping dissect the genetic and molecular underpinnings of Rhodnius embryogenesis and organogenesis, thus fostering the use of this important species in the fields of developmental and evolutionary biology. Rhodnius represents also an excellent system to study development under stressful conditions, since the embryo must develop in the presence of a large amount of blood-derived reactive oxygen species. With a recently sequenced genome, small among other Hemiptera, and the identification of basic elements for all classical development pathways, functional studies in this species are revealing novel aspects of insect development and evolution. Here we review early studies on this model insect and how this paved the way for recent functional studies using the kissing bug.


Assuntos
Insetos Vetores/crescimento & desenvolvimento , Rhodnius/crescimento & desenvolvimento , Animais , Desenvolvimento Embrionário , Evolução Molecular , Insetos Vetores/genética , Insetos Vetores/fisiologia , Rhodnius/genética , Rhodnius/fisiologia
9.
Genesis ; 55(5)2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-28432834

RESUMO

The development of a digestive system is an essential feature of bilaterians. Studies of the molecular control of gut formation in arthropods have been studied in detail in the fruit fly Drosophila melanogaster. However, little is known in other arthropods, especially in noninsect arthropods. To better understand the evolution of arthropod alimentary system, we investigate the molecular control of gut development in the spider Parasteatoda tepidariorum (Pt), the primary chelicerate model species for developmental studies. Orthologs of the ectodermal genes Pt-wingless (Pt-wg) and Pt-hedgehog (Pt-hh), of the endodermal genes, Pt-serpent (Pt-srp) and Pt-hepatocyte-nuclear factor-4 (Pt-hnf4) and of the mesodermal gene Pt-twist (Pt-twi) are expressed in the same germ layers during spider gut development as in D. melanogaster. Thus, our expression data suggest that the downstream molecular components involved in gut development in arthropods are conserved. However, Pt-forkhead (Pt-fkh) expression and function in spiders is considerably different from its D. melanogaster ortholog. Pt-fkh is expressed before gastrulation in a cell population that gives rise to endodermal and mesodermal precursors, suggesting a possible role for this factor in specification of both germ layers. To test this hypothesis, we knocked down Pt-fkh via RNA interference. Pt-fkh RNAi embryos not only fail to develop a proper gut, but also lack the mesodermal Pt-twi expressing cells. Thus, in spiders Pt-fkh specifies endodermal and mesodermal germ layers. We discuss the implications of these findings for the evolution and development of gut formation in Ecdysozoans.


Assuntos
Regulação da Expressão Gênica no Desenvolvimento , Intestinos/embriologia , Aranhas/genética , Animais , Feminino , Camadas Germinativas/embriologia , Camadas Germinativas/metabolismo , Mucosa Intestinal/metabolismo , Masculino , Aranhas/embriologia , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
10.
Brain Behav Immun ; 61: 289-296, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28089640

RESUMO

The stress response is a complex mechanism, which includes changes in the immune system to enable organisms to maintain homeostasis. The neurohormones dopamine, noradrenaline (NA) and adrenalin are responsible for the physiological modulations that occur during acute stress. In the present study, we analyzed the effects of NA on the immune system specific to nitric-oxide (NO) production by subpopulations of immune cells (hemocytes) of the ascidian Phallusia nigra. We also investigated the capability of immune cells to produce catecholamine (CA). Finally, we tested the involvement of protein kinase A (PKA) and C (PKC) in the NA downstream signaling pathway. The results revealed that NA can reduce NO production by P. nigra hemocytes threefold, and that signet-ring cells, univacuolar refractile granulocytes and morula cells are the cell types most involved in this event. A challenge effected with Zymosan A induced CA production, and co-incubation with both inhibitors of the second messengers PKA and PKC revealed the involvement of these molecules in the adrenergic pathway of P. nigra hemocytes. Taken together, these results suggest that NO production can be down-regulated by NA through α- and ß-adrenoceptors via the second messengers PKA and PKC.


Assuntos
Catecolaminas/metabolismo , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Hemócitos/metabolismo , Proteína Quinase C/metabolismo , Transdução de Sinais/fisiologia , Urocordados/metabolismo , Animais , Óxido Nítrico/biossíntese
11.
Mar Drugs ; 14(2)2016 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-26821032

RESUMO

Dengue is considered a serious public health problem in many tropical regions of the world including Brazil. At the moment, there is no viable alternative to reduce dengue infections other than controlling the insect vector, Aedes aegypti Linnaeus. In the continuing search for new sources of chemicals targeted at vector control, natural products are a promising alternative to synthetic pesticides. In our work, we investigated the toxicity of a bioactive compound extracted from the red alga Laurencia dendroidea J. Agardh. The initial results demonstrated that crude extracts, at a concentration of 5 ppm, caused pronounced mortality of second instar A. aegypti larvae. Two molecules, identified as (-)-elatol and (+)-obtusol were subsequently isolated from crude extract and further evaluated. Assays with (-)-elatol showed moderate larvicidal activity, whereas (+)-obtusol presented higher toxic activity than (-)-elatol, with a LC50 value of 3.5 ppm. Histological analysis of the larvae exposed to (+)-obtusol revealed damage to the intestinal epithelium. Moreover, (+)-obtusol-treated larvae incubated with 2 µM CM-H2DCFDA showed the presence of reactive oxygen species, leading us to suggest that epithelial damage might be related to redox imbalance. These results demonstrate the potential of (+)-obtusol as a larvicide for use against A. aegypti and the possible mode of action of this compound.


Assuntos
Inseticidas/farmacologia , Laurencia/química , Sesquiterpenos/farmacologia , Aedes , Animais , Brasil , Dengue/transmissão , Controle de Insetos/métodos , Insetos Vetores , Inseticidas/administração & dosagem , Inseticidas/isolamento & purificação , Larva/efeitos dos fármacos , Dose Letal Mediana , Espécies Reativas de Oxigênio/metabolismo , Sesquiterpenos/administração & dosagem , Sesquiterpenos/isolamento & purificação
13.
Int J Mol Sci ; 16(4): 6631-44, 2015 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-25811926

RESUMO

Polyphosphates have been found in all cell types examined to date and play diverse roles depending on the cell type. In eukaryotic organisms, polyphosphates have been mainly investigated in mammalian cells with few studies on insects. Some studies have demonstrated that a pyrophosphatase regulates polyphosphate metabolism, and most of them were performed on trypanosomatids. Here, we investigated the effects of sPPase gene knocked down in oogenesis and polyphosphate metabolism in the red flour beetle (Tribolium castaneum). A single sPPase gene was identified in insect genome and is maternally provided at the mRNA level and not restricted to any embryonic or extraembryonic region during embryogenesis. After injection of Tc-sPPase dsRNA, female survival was reduced to 15% of the control (dsNeo RNA), and egg laying was completely impaired. The morphological analysis by nuclear DAPI staining of the ovarioles in Tc-sPPase dsRNA-injected females showed that the ovariole number is diminished, degenerated oocytes can be observed, and germarium is reduced. The polyphosphate level was increased in cytoplasmic and nuclear fractions in Tc-sPPase RNAi; Concomitantly, the exopolyphosphatase activity decreased in both fractions. Altogether, these data suggest a role for sPPase in the regulation on polyphosphate metabolism in insects and provide evidence that Tc-sPPase is essential to oogenesis.


Assuntos
Proteínas de Insetos , Oogênese , Polifosfatos/metabolismo , Pirofosfatases/genética , Tribolium/enzimologia , Animais , Feminino , Regulação da Expressão Gênica no Desenvolvimento , Técnicas de Silenciamento de Genes , Proteínas de Insetos/metabolismo , Filogenia , Pirofosfatases/metabolismo
14.
Artigo em Inglês | MEDLINE | ID: mdl-38460106

RESUMO

Spiders produce webs, which are still a largely unexplored source of antibacterial compounds, although the reports of its application in the medical field. Therefore, this study aims to present an integrative review of the antibacterial activity of spider webs. The research was conducted using Google Scholar, Scielo, Web of Science, PubMed, ScienceDirect, Medline EBSCO, LILACS, and Embase. The inclusion criteria were original articles written in English that studied the antibiotic properties of the web or isolated compounds tested. The studies were compared according to the spider species studied, the type of web, treatment of the sample, type of antimicrobial test, and the results obtained. Nine hundred and seventy-three publications were found, and after applying the inclusion and exclusion criteria, sixteen articles were selected. Bacterial inhibition was found in seven studies against various species of bacteria such as Escherichia coli, Klebsiella pneumoniae, Staphylococcus aureus, Salmonella Typhi, Bacillus megaterium, Listeria monocytogenes, Acinetobacter baumannii, Streptococcus pneumoniae, Pasteurella multocida, and Bacillus subtilis. Additionally, there was no apparent relationship between the proximity of the spider species evaluated in the studies and the presence or absence of activity. Methodological problems detected may affected the reproducibility and reliability of the results in some studies, such as the lack of description of the web or microorganism strain, as well as the absence of adequate controls and treatments to sterilize the sample. Spider webs can be a valuable source of antibiotics; however, more studies are needed to confirm the real activity of the web or components involved.

15.
Insect Biochem Mol Biol ; : 104154, 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38972513

RESUMO

Chagas disease affects around 8 million people globally, with Latin America bearing approximately 10,000 deaths each year. Combatting the disease relies heavily on vector control methods, necessitating the identification of new targets. Within insect genomes, genes harboring small open reading frames (smORFs - < 100 amino acids) present numerous potential candidates. In our investigation, we elucidate the pivotal role of the archetypal smORF-containing gene, mille-pattes/polished-rice/tarsalless (mlpt/pri/tal), in the post-embryonic development of the kissing bug Rhodnius prolixus. Injection of double-stranded RNA targeting mlpt (dsmlpt) during nymphal stages yields a spectrum of phenotypes hindering post-embryonic growth. Notably, fourth or fifth stage nymphs subjected to dsmlpt do not undergo molting. These dsmlpt nymphs display heightened mRNA levels of JHAMT-like and EPOX-like, enzymes putatively involved in the juvenile hormone (JH) pathway, alongside increased expression of the transcription factor Kr-h1, indicating changes in the hormonal control. Histological examination reveals structural alterations in the hindgut and external cuticle of dsmlpt nymphs compared to control (dsGFP) counterparts. Furthermore, significant changes in the vector's digestive physiology were observed, with elevated hemozoin and glucose levels in the posterior midgut of dsmlpt nymphs. Importantly, dsmlpt nymphs exhibit impaired metacyclogenesis of Trypanosoma cruzi, the causative agent of Chagas disease, underscoring the crucial role of proper gut organization in parasite differentiation. Thus, our findings constitute the first evidence of a smORF-containing gene's regulatory influence on vector physiology, parasitic cycle, and disease transmission.

16.
PeerJ ; 10: e14547, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36540807

RESUMO

Objective: To analyze the long-term dynamics of antibodies against SARS-CoV-2 and understand the impact of age, gender, and viral load on patients' immunological response. Methods: Serum samples were obtained from 231 COVID-19 positive patients from Macaé, in Rio de Janeiro state, in Brazil, from June 2020 until January 2021. The production of IgA, IgM, IgG, and IgE against S glycoprotein was analyzed using the S-UFRJ assay, taking into account the age, gender, and viral load. Results: Analysis of antibody production over 7 months revealed that IgA positivity gradually decreased after the first month. Additionally, the highest percentage of IgM positivity occurred in the first month (97% of patients), and declined after this period, while IgG positivity remained homogeneous for all 7 months. The same analysis for IgE revealed that almost all samples were negative. The comparison of antibody production between genders showed no significant difference. Regarding the age factor and antibody production, patients aged ≥60 years produced almost twice more IgA than younger ones (17-39 years old). Finally, a relationship between viral load and antibody production was observed only for older patients. Conclusions: Our work provides an overview of long-term production of antibodies against SARS-CoV-2, suggesting prolonged production of IgA and IgM antibodies for 3 months and continued IgG production for over 7 months. In addition, it identified a correlation between viral load and IgM titers in the older group and, finally, different IgA production between the age groups.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , Feminino , Masculino , Adolescente , Adulto Jovem , Adulto , Anticorpos Antivirais , Imunoglobulina G , Brasil/epidemiologia , Imunoglobulina M , Imunoglobulina A , Imunoglobulina E
17.
Dev Biol ; 345(1): 80-93, 2010 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-20510683

RESUMO

The formation of the BMP gradient which patterns the DV axis in flies and vertebrates requires several extracellular modulators like the inhibitory protein Sog/Chordin, the metalloprotease Tolloid (Tld), which cleaves Sog/Chordin, and the CR domain protein Twisted gastrulation (Tsg). While flies and vertebrates have only one sog/chordin gene they possess several paralogues of tld and tsg. A simpler and probably ancestral situation is observed in the short-germ beetle Tribolium castaneum (Tc), which possesses only one tld and one tsg gene. Here we show that in T. castaneum tld is required for early BMP signalling except in the head region and Tc-tld function is, as expected, dependent on Tc-sog. In contrast, Tc-tsg is required for all aspects of early BMP signalling and acts in a Tc-sog-independent manner. For comparison with Drosophila melanogaster we constructed fly embryos lacking all early Tsg activity (tsg;;srw double mutants) and show that they still establish a BMP signalling gradient. Thus, our results suggest that the role of Tsg proteins for BMP gradient formation has changed during insect evolution.


Assuntos
Evolução Molecular , Proteínas de Insetos/genética , Insetos/genética , Filogenia , Animais , Padronização Corporal/genética , Proteínas Morfogenéticas Ósseas/genética , Proteínas Morfogenéticas Ósseas/metabolismo , Proteínas de Drosophila/genética , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/embriologia , Drosophila melanogaster/genética , Embrião não Mamífero/embriologia , Embrião não Mamífero/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Imuno-Histoquímica , Hibridização In Situ , Proteínas de Insetos/classificação , Proteínas de Insetos/metabolismo , Insetos/classificação , Insetos/embriologia , Interferência de RNA , Metaloproteases Semelhantes a Toloide/genética , Metaloproteases Semelhantes a Toloide/metabolismo , Tribolium/embriologia , Tribolium/genética
18.
DNA Res ; 28(5)2021 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-34240112

RESUMO

Small open reading frames (small ORFs/sORFs/smORFs) are potentially coding sequences smaller than 100 codons that have historically been considered junk DNA by gene prediction software and in annotation screening; however, the advent of next-generation sequencing has contributed to the deeper investigation of junk DNA regions and their transcription products, resulting in the emergence of smORFs as a new focus of interest in systems biology. Several smORF peptides were recently reported in non-canonical mRNAs as new players in numerous biological contexts; however, their relevance is still overlooked in coding potential analysis. Hence, this review proposes a smORF classification based on transcriptional features, discussing the most promising approaches to investigate smORFs based on their different characteristics. First, smORFs were divided into non-expressed (intergenic) and expressed (genic) smORFs. Second, genic smORFs were classified as smORFs located in non-coding RNAs (ncRNAs) or canonical mRNAs. Finally, smORFs in ncRNAs were further subdivided into sequences located in small or long RNAs, whereas smORFs located in canonical mRNAs were subdivided into several specific classes depending on their localization along the gene. We hope that this review provides new insights into large-scale annotations and reinforces the role of smORFs as essential components of a hidden coding DNA world.


Assuntos
Peptídeos , RNA não Traduzido , Sequenciamento de Nucleotídeos em Larga Escala , Fases de Leitura Aberta , Peptídeos/genética , RNA Mensageiro/genética , RNA não Traduzido/genética
19.
PeerJ ; 9: e11214, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33954044

RESUMO

The fish embryo test (FET) is an alternative to the classic freshwater toxicity test used to assess environmental hazards and risks to fish. This test has been standardized and adopted by the Organization for Economic and Cooperation and Development (OECD). As salinity may affect the substances' toxicity, we describe the development of an alternative euryhaline test species for embryonic ecotoxicological tests: the Brazilian silverside Atherinella brasiliensis (Quoy & Gaimard, 1825). This species is broadly distributed along the coast of South America and is able to inhabit a broad range of environmental and saline conditions. Ours is the first study on the maintenance of a native South American species for natural reproduction and the generation of embryos for tests. The embryos used are transparent and possess fluorescent cells which have only been seen in a few species and which may be used as markers, making it an alternative assessment tool for the lethal and sublethal substances in marine and estuarine environments. We provide a detailed description and analysis of embryonic development under different salinities and temperatures. The embryos and larvae developed in similar ways at different salinities, however as temperatures increased, mortality also increased. We considered the effects of the reference toxicants Zn2+ and SDS using a protocol similar to the FET that was standardized for zebrafish. Brazilian silverside embryos are as sensitive as freshwater, or euryhaline fish, to the surfactant but are more resistant to metals prior to hatching. We were able to show the advantages of the Brazilian silverside as a model for a marine fish embryo test (FETm) with high levels of reproducibility and little contaminated waste.

20.
Sci Rep ; 11(1): 20121, 2021 10 11.
Artigo em Inglês | MEDLINE | ID: mdl-34635707

RESUMO

The Brazilian strategy to overcome the spread of COVID-19 has been particularly criticized due to the lack of a national coordinating effort and an appropriate testing program. Here, a successful approach to control the spread of COVID-19 transmission is described by the engagement of public (university and governance) and private sectors (hospitals and oil companies) in Macaé, state of Rio de Janeiro, Brazil, a city known as the National Oil Capital. In 2020 between the 17th and 38th epidemiological week, over two percent of the 206,728 citizens were subjected to symptom analysis and RT-qPCR testing by the Federal University of Rio de Janeiro, with positive individuals being notified up to 48 h after swab collection. Geocodification and spatial cluster analysis were used to limit COVID-19 spreading in Macaé. Within the first semester after the outbreak of COVID-19 in Brazil, Macaé recorded 1.8% of fatalities associated with COVID-19 up to the 38th epidemiological week, which was at least five times lower than the state capital (10.6%). Overall, considering the successful experience of this joint effort of private and public engagement in Macaé, our data suggest that the development of a similar strategy countrywise could have contributed to a better control of the COVID-19 spread in Brazil. Quarantine decree by the local administration, comprehensive molecular testing coupled to scientific analysis of COVID-19 spreading, prevented the catastrophic consequences of the pandemic as seen in other populous cities within the state of Rio de Janeiro and elsewhere in Brazil.


Assuntos
Teste de Ácido Nucleico para COVID-19/estatística & dados numéricos , COVID-19/epidemiologia , Pandemias/estatística & dados numéricos , SARS-CoV-2/isolamento & purificação , Adolescente , Adulto , Idoso , Brasil/epidemiologia , COVID-19/diagnóstico , COVID-19/transmissão , COVID-19/virologia , Cidades/epidemiologia , Cidades/estatística & dados numéricos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , RNA Viral/isolamento & purificação , SARS-CoV-2/genética , Adulto Jovem
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