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1.
J Biol Chem ; 298(4): 101723, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35157847

RESUMO

A wide range of protein acyl modifications has been identified on enzymes across various metabolic processes; however, the impact of these modifications remains poorly understood. Protein glutarylation is a recently identified modification that can be nonenzymatically driven by glutaryl-CoA. In mammalian systems, this unique metabolite is only produced in the lysine and tryptophan oxidative pathways. To better understand the biology of protein glutarylation, we studied the relationship between enzymes within the lysine/tryptophan catabolic pathways, protein glutarylation, and regulation by the deglutarylating enzyme sirtuin 5 (SIRT5). Here, we identify glutarylation on the lysine oxidation pathway enzyme glutaryl-CoA dehydrogenase (GCDH) and show increased GCDH glutarylation when glutaryl-CoA production is stimulated by lysine catabolism. Our data reveal that glutarylation of GCDH impacts its function, ultimately decreasing lysine oxidation. We also demonstrate the ability of SIRT5 to deglutarylate GCDH, restoring its enzymatic activity. Finally, metabolomic and bioinformatic analyses indicate an expanded role for SIRT5 in regulating amino acid metabolism. Together, these data support a feedback loop model within the lysine/tryptophan oxidation pathway in which glutaryl-CoA is produced, in turn inhibiting GCDH function via glutaryl modification of GCDH lysine residues and can be relieved by SIRT5 deacylation activity.


Assuntos
Glutaril-CoA Desidrogenase , Lisina , Sirtuínas , Animais , Glutaril-CoA Desidrogenase/metabolismo , Lisina/metabolismo , Camundongos , Oxirredução , Processamento de Proteína Pós-Traducional , Sirtuínas/metabolismo , Triptofano/metabolismo
2.
Cell Mol Life Sci ; 77(23): 4957-4976, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31927610

RESUMO

Macrophages are key effector cells in obesity-associated inflammation. G protein-coupled receptor kinase 2 (GRK2) is highly expressed in different immune cell types. Using LysM-GRK2+/- mice, we uncover that a reduction of GRK2 levels in myeloid cells prevents the development of glucose intolerance and hyperglycemia after a high fat diet (HFD) through modulation of the macrophage pro-inflammatory profile. Low levels of myeloid GRK2 confer protection against hepatic insulin resistance, steatosis and inflammation. In adipose tissue, pro-inflammatory cytokines are reduced and insulin signaling is preserved. Macrophages from LysM-GRK2+/- mice secrete less pro-inflammatory cytokines when stimulated with lipopolysaccharide (LPS) and their conditioned media has a reduced pathological influence in cultured adipocytes or naïve bone marrow-derived macrophages. Our data indicate that reducing GRK2 levels in myeloid cells, by attenuating pro-inflammatory features of macrophages, has a relevant impact in adipose-liver crosstalk, thus preventing high fat diet-induced metabolic alterations.


Assuntos
Tecido Adiposo/metabolismo , Dieta Hiperlipídica , Quinase 2 de Receptor Acoplado a Proteína G/metabolismo , Fígado/metabolismo , Células Mieloides/metabolismo , Obesidade/metabolismo , Adipócitos/efeitos dos fármacos , Adipócitos/metabolismo , Adipócitos/patologia , Tecido Adiposo Branco/patologia , Animais , Meios de Cultivo Condicionados/farmacologia , Citoproteção/efeitos dos fármacos , Fígado Gorduroso/complicações , Fígado Gorduroso/patologia , Microbioma Gastrointestinal/efeitos dos fármacos , Glucose/metabolismo , Intolerância à Glucose/metabolismo , Hipertrofia , Inflamação/patologia , Insulina/metabolismo , Resistência à Insulina , Macrófagos Peritoneais/efeitos dos fármacos , Macrófagos Peritoneais/metabolismo , Camundongos Endogâmicos C57BL , Modelos Biológicos , Células Mieloides/efeitos dos fármacos , Obesidade/complicações , Transdução de Sinais/efeitos dos fármacos , Aumento de Peso/efeitos dos fármacos
3.
BMC Plant Biol ; 18(1): 105, 2018 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-29866051

RESUMO

BACKGROUND: The release of phytosiderephores (PS) to the rhizosphere is the main root response to iron (Fe) deficiency in graminaceous plants. We have investigated the role of the Fe status in the shoot as well as of the signaling pathways controlled by three relevant phytoregulators - indolacetic acid (IAA), ethylene and nitric oxide (NO) - in the regulation of this root response in Fe-starved wheat plants. To this end, the PS accumulation in the nutrient solution and the root expression of the genes encoding the nicotianamine aminotransferase (TaNAAT) and ferritin (TaFER) have been evaluated in plants subjected to different treatments. RESULTS: The application of Fe to leaves of Fe-deficient plants prevented the increase in both PS root release and TaNAAT gene expression thus showing the relevant role of the shoot to root communication in the regulation of PS root release and some steps of PS biosynthesis. Experiments with specific hormone inhibitors showed that while ethylene and NO did not positively regulate Fe-deficiency induced PS root release, auxin plays an essential role in the regulation of this process. Moreover, the application of IAA to Fe-sufficient plants promoted both PS root release and TaNAAT gene expression thus indicating that auxin might be involved in the shoot to root signaling network regulating Fe-deficiency root responses in wheat. CONCLUSIONS: These results therefore indicate that PS root release in Fe-deficient wheat plants is directly modulated by the shoot Fe status through signaling pathways involving, among other possible effectors, auxin.


Assuntos
Ácido Azetidinocarboxílico/análogos & derivados , Ácidos Indolacéticos/metabolismo , Ferro/metabolismo , Reguladores de Crescimento de Plantas/metabolismo , Sideróforos/metabolismo , Triticum/fisiologia , Ácido Azetidinocarboxílico/metabolismo , Deficiências de Ferro , Folhas de Planta/genética , Folhas de Planta/fisiologia , Raízes de Plantas/genética , Raízes de Plantas/fisiologia , Brotos de Planta/genética , Brotos de Planta/fisiologia , Transdução de Sinais , Triticum/genética
4.
Pharmacol Res ; 108: 46-56, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-27073018

RESUMO

Endothelial cells (EC) are able to actively control vascular permeability, coagulation, blood pressure and angiogenesis. Most recently, a role for endothelial cells in the immune response has been described. Therefore, the endothelium has a dual role controlling homeostasis but also being the first line for host defence and tissue damage repair thanks to its ability to mount an inflammatory response. Endothelial cells have been shown to express pattern-recognition receptors (PRR) including Toll-like receptors (TLR) that are activated in response to stimuli within the bloodstream including pathogens and damage signals. TLRs are strategic mediators of the immune response in endothelial cells but they also regulate the angiogenic process critical for tissue repair. Nevertheless, endothelial activation and angiogenesis can contribute to some pathologies. Thus, inappropriate endothelial activation, also known as endothelial dysfunction, through TLRs contributes to tissue damage during autoimmune and inflammatory diseases such as atherosclerosis, hypertension, ischemia and diabetes associated cardiovascular diseases. Also TLR induced angiogenesis is required for the growth of some tumors, atherosclerosis and rheumatoid arthritis, among others. In this review we discuss the importance of various TLRs in modulating the activation of endothelial cells and their importance in immunity to infection and vascular disease as well as their potential as therapeutic targets.


Assuntos
Células Endoteliais/imunologia , Inflamação/imunologia , Neovascularização Patológica/imunologia , Receptores Toll-Like/imunologia , Doenças Vasculares/imunologia , Animais , Descoberta de Drogas , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/patologia , Humanos , Inflamação/tratamento farmacológico , Inflamação/patologia , Terapia de Alvo Molecular , Neovascularização Patológica/tratamento farmacológico , Neovascularização Patológica/patologia , Neovascularização Fisiológica/efeitos dos fármacos , Doenças Vasculares/tratamento farmacológico , Doenças Vasculares/patologia
5.
Mol Phylogenet Evol ; 80: 281-96, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25132127

RESUMO

Genetic factors have direct and indirect impacts in the viability of endangered species. Assessing their genetic diversity levels and population structure is thus fundamental for conservation and management. In this paper we use mitochondrial and nuclear markers to address phylogeographic and demographic data on the critically endangered Anaecypris hispanica, using a broad sampling set which covered its known distribution area in the Iberian Peninsula. Our results showed that the populations of A. hispanica are strongly differentiated (high and significant ФST and FST values, corroborated by the results from AMOVA and SAMOVA) and genetically diversified. We suggest that the restricted gene flow between populations may have been potentiated by ecological, hydrological and anthropogenic causes. Bayesian skyline plots revealed a signal for expansion for all populations (tMRCA between 68kya and 1.33Mya) and a genetic diversity latitudinal gradient was detected between the populations from the Upper (more diversified) and the Lower (less diversified) Guadiana river basin. We postulate a Pleistocenic westwards colonization route for A. hispanica in the Guadiana river basin, which is in agreement with the tempo and mode of paleoevolution of this drainage. The colonization of River Guadalquivir around 60kya with migrants from the Upper Guadiana, most likely by stream capture, is also suggested. This study highlights the view that critically endangered species facing range retreats (about 47% of its known populations have disappeared in the last 15years) are not necessarily small and genetically depleted. However, the extinction risk is not negligible since A. hispanica faces the combined effect of several deterministic and stochastic negative factors and, moreover, recolonization events after localized extinctions are very unlikely to occur due to the strong isolation of populations and to the patchily ecologically-conditioned distribution of fish. The inferred species distribution models highlight the significant contribution of temperature seasonality and isothermality to A. hispanica occurrence in Guadiana environments and emphasize the importance of stable climatic conditions for the preservation of this species. Given the strong population structure, high percentage of private haplotypes and virtual absence of inter-basin gene flow we suggest that each A. hispanica population should be considered as an independent Operational Conservation Unit and that ex-situ and in-situ actions should be conducted in parallel to allow for the long-term survival of the species and the preservation of the genetic integrity of its populations.


Assuntos
Cyprinidae/genética , Secas , Espécies em Perigo de Extinção , Inundações , Variação Genética , Animais , Teorema de Bayes , Conservação dos Recursos Naturais , DNA Mitocondrial/genética , Fluxo Gênico , Haplótipos , Modelos Genéticos , Filogenia , Filogeografia , Dinâmica Populacional , Rios , Análise de Sequência de DNA , Espanha
6.
PLoS One ; 18(1): e0280828, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36696430

RESUMO

The 2020 Vice-Presidential debate afforded the opportunity to examine online reactions toward a woman of color, Kamala Harris, and a white man, Mike Pence, as they vied for the same position. We collected tweets from the Twitter API related to Harris and Pence, mainly using neutral hashtags. We examined keywords for gender and race slurs and conducted a multivariate analysis of tweet sentiment. Gender and racial slurs surface in both Harris and Pence datasets, showcasing the insidious nature of sexist and racist stereotypes that seep into online conversations regarding a high-status job debate. As anticipated, tweets regarding Harris contained a higher proportion of racist and sexist curse words, highlighting greater levels of harassment and "intersectional," multi-ethnic/gender attacks. Racial insults targeting Blacks or Asians were more negative than those associated with Whites. Unexpectedly, tweets related to Harris were more positive in average sentiment than those regarding Pence. Yet, there were significantly more retweets, and more negativity of retweets, relating to Harris than to Pence, underscoring the relatively widespread broadcasting of derogatory messages about Harris. Overall, we found that harassing messages toward the candidates reinforced traditional race and gender stereotypes and bolstered the status of those who posted negative content by attaining more retweets. Harassers routinely invoked well-worn, stereotypical insults in their attacks, especially when targeting a multiracial woman.


Assuntos
Mídias Sociais , Masculino , Feminino , Humanos , Grupos Raciais , Asiático , Comunicação , Comportamento Estereotipado
7.
Soc Sci Med ; 316: 114265, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-34366168

RESUMO

RATIONALE: Black Lives Matter (BLM) is a social movement against systematic injustice and police violence toward Black people whose goal is to ensure their safety and the expression of their culture. As BLM gained momentum, counter-movements emerged, such as All Lives Matter (ALM), White Lives Matter (WLM), and Blue Lives Matter (BlueLM). Because they undermine support for Black people's safety and culture, exposure to stances against BLM can be a race-related stressor. Although the perception of racial discrimination has been associated with negative health outcomes in Black people, it is not clear whether exposure to negative stances on a race-related social issue is associated with worse health outcomes. OBJECTIVE: We investigated whether living in areas of the United States with a high prevalence of negative stances on BLM is associated with worse health outcomes, such as higher body mass index (BMI) and prevalence of obesity. METHODS: We scraped geo-coded tweets (N = 51,020) that contained #BLM, #ALM, #WLM, and #BlueLM from 2014 to 2016. We determined the stances of the tweets on BLM using machine learning algorithms and aggregated stances at the metropolitan or micropolitan statistical area (MMSA) levels. Participants' BMI and obesity status were derived from the 2017 BRFSS SMART data in 76 MMSAs, as compiled by the Centers for Disease Control and Prevention (N = 20,530). RESULTS: After controlling for individual- and regional-level covariates, regional measures of racism and police brutality rate, and baseline BMI in 2014 aggregated on MMSA level, Black people had a higher BMI and prevalence of obesity in areas that showed higher negative stances on BLM. Stances against BLM were positively associated with implicit racism against Black people and can be an acute race-related stressor associated with negative downstream health outcomes. CONCLUSION: Negative societal sentiments around race-related issues may be detrimental to the health outcomes of minority populations.


Assuntos
Obesidade , Racismo , Humanos , Estados Unidos/epidemiologia , Obesidade/epidemiologia , Atitude , Índice de Massa Corporal , Polícia
8.
Int J Biometeorol ; 56(2): 319-32, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21553333

RESUMO

The present experimental work is dedicated to the analysis of the effect of walking on the thermal insulation of the air layer (I (a)) and on the convective heat transfer coefficients (h (conv)) of the human body. Beyond the standing static posture, three step rates were considered: 20, 30 and 45 steps/min. This corresponds to walking speeds of approximately 0.23, 0.34 and 0.51 m/s, respectively. The experiments took place in a climate chamber with an articulated thermal manikin with 16 independent parts. The indoor environment was controlled through the inner wall temperatures since the objective of the tests was restricted to the influence of the walking movements under calm conditions. Five set points were selected: 10, 15, 20, 25 and 30°C, and the operative temperature within the test chamber varied between 11.9 and 29.6°C. The highest and lowest I ( a ) values obtained were equal to 0.87 and 0.71 clo, respectively, and the reduction in insulation due to walking ranged between 9.8 and 11.5%. The convective coefficients (h (conv)) for the whole body and for the different body segments were also determined for each step rate. In the case of the whole body, for the standing static reference posture, the mean value of h (conv) was equal to 3.3 W/m(2)°C and a correlation [Nu = Nu(Gr)] for natural convection is also presented in good agreement with previous results. For the other postures, the values of h (conv) were equal to 3.7, 3.9 and 4.2 W/m(2)°C, respectively for 20, 30 and 45 steps/min.


Assuntos
Regulação da Temperatura Corporal/fisiologia , Convecção , Manequins , Temperatura Cutânea/fisiologia , Condutividade Térmica , Caminhada/fisiologia , Algoritmos , Humanos , Modelos Biológicos , Temperatura
9.
Front Plant Sci ; 13: 803013, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35185979

RESUMO

Many studies have shown the close relationship between the beneficial action of soil and sedimentary humic acids on the growth of plants cultivated in calcareous soils and their ability to improve Fe plant nutrition. These results have been ascribed to the humic acid (HA) capability to improve Fe solubility and bioavailability. However, other effects more related to a humic acid action on the specific mechanisms activated in roots of plants under Fe deficiency cannot be ruled out. Although this question has been studied in dicotyledonous plants, in graminaceous plants there are no specific studies. Here we investigate the ability of a humic acid extracted from peat (HA) to improve Fe nutrition in wheat plants cultivated under Fe deficient and sufficient conditions. The results show that HA can improve the physiological status of Fe deficient wheat plants by alleviating some of the deleterious consequences of Fe deficiency on plant development and increasing the plant ability to secrete phytosiderophores to the nutrient solution. This action of HA is associated with increases in the Fe-active pool in leaves that might be related to the mobilization of the Fe complexed by HA resulting from the interaction of HA with the phytosiderophores in the nutrient solution. The Fe translocation from the root to the shoot may be favored by the action of trans-Zeatin Riboside (tZR) since the leaf concentration of this phytohormone was enhanced by HA in Fe deficient plants.

10.
Sci Rep ; 12(1): 22124, 2022 12 21.
Artigo em Inglês | MEDLINE | ID: mdl-36543927

RESUMO

Marine species exhibiting wide distributional ranges are frequently subdivided into discrete genetic units over limited spatial scales. This is often due to specific life-history traits or oceanographic barriers that prevent gene flow. Fine-scale sampling studies revealed distinct phylogeographic patterns in the northeastern Atlantic and the Mediterranean, ranging from panmixia to noticeable population genetic structure. Here, we used mitochondrial sequence data to analyse connectivity in the bogue Boops boops throughout most of its widespread distribution. Our results identified the existence of three clades, one comprising specimens from the Azores and eastern Atlantic/Mediterranean, another with individuals from the Canary Islands, Madeira and Cape Verde archipelagos, and the third with samples from Mauritania only. One of the branches of the northern subtropical gyre (Azores Current) that drifts towards the Gulf of Cádiz promotes a closer connection between the Azores, southern Portugal and the Mediterranean B. boops populations. The Almería-Oran Front, widely recognised as an oceanographic barrier for many organisms to cross the Atlantic-Mediterranean divide, does not seem to affect the dispersal of this benthopelagic species. The southward movement of the Cape Verde Frontal Zone during the winter, combined with the relatively short duration of the pelagic larval stage of B. boops, may be potential factors for preventing the connectivity between the Atlantic oceanic archipelagos and Mauritania shaping the genetic signature of this species.


Assuntos
Mitocôndrias , Perciformes , Humanos , Animais , Filogenia , Filogeografia , Açores , Portugal , Perciformes/genética , Oceano Atlântico , Variação Genética , Mar Mediterrâneo
11.
J Sci Food Agric ; 91(9): 1569-75, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21656770

RESUMO

BACKGROUND: Some authors suggest that the absence of tillage in agricultural soils might have an influence on the efficiency of nitrogen applied in the soil surface. In this study we investigate the influence of no-tillage and soil characteristics on the efficiency of a urease inhibitor (N-(n-butyl)thiophosphoric triamide, NBPT) and a nitrification inhibitor (diciandiamide, DCD) in decreasing ammonia volatilization from urea and ammonium nitrate (AN), respectively. RESULTS: The results indicate that ammonia volatilization in soils amended with urea was significantly higher than in those fertilized with AN. Likewise, the main soil factors affecting ammonia volatilization from urea are clay and sand soil contents. While clay impedes ammonia volatilization, sand favours it. The presence of organic residues on soil surface (no-tillage) tends to increase ammonia volatilization from urea, although this fact depended on soil type. The presence of NBPT in urea fertilizer significantly reduced soil ammonia volatilization. This action of NBPT was negatively affected by acid soil pH and favoured by soil clay content. CONCLUSION: The presence of organic residues on soil surface amended with urea increased ammonia volatilization, and was particularly high in sandy compared with clay soils. Application of NBPT reduced ammonia volatilization although its efficiency is reduced in acid soils. Concerning AN fertilization, there were no differences in ammonia volatilization with or without DCD in no-tillage soils.


Assuntos
Amônia/metabolismo , Fertilizantes , Substâncias Húmicas , Nitrificação , Nitrogênio/metabolismo , Solo , Urease/antagonistas & inibidores , Agricultura/métodos , Silicatos de Alumínio , Argila , Inibidores Enzimáticos , Concentração de Íons de Hidrogênio , Nitratos/metabolismo , Compostos Organofosforados , Caules de Planta , Dióxido de Silício , Triticum , Ureia/metabolismo , Volatilização
12.
J Interpers Violence ; 36(7-8): 3117-3141, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-29756558

RESUMO

Throughout North America, indigenous women experience higher rates of intimate partner violence and sexual violence than any other ethnic group, and so it is of particular importance to understand sources of support for Native American women. In this article, we use social network analysis to study the relationship between social integration and women's access to domestic violence support by examining the recommendations they would give to another woman in need. We ask two main questions: First, are less integrated women more likely to make no recommendation at all when compared with more socially integrated women? Second, are less integrated women more likely than more integrated women to nominate a formal source of support rather than an informal one? We use network data collected from interviews with 158 Canadian women residing in an indigenous community to measure their access to support. We find that, in general, less integrated women are less likely to make a recommendation than more integrated women. However, when they do make a recommendation, less integrated women are more likely to recommend a formal source of support than women who are more integrated. These results add to our understanding of how access to two types of domestic violence support is embedded in the larger set of social relations of an indigenous community.


Assuntos
Violência Doméstica , Violência por Parceiro Íntimo , Delitos Sexuais , Canadá , Feminino , Humanos , Integração Social , Apoio Social
13.
Front Immunol ; 12: 660065, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34234775

RESUMO

Toll-like receptors (TLRs) play a crucial role in the recognition of pathogen-derived components as a first line of defense against infections. It has been suggested that depending on the nature of the pathogens, TLRs activation induce a distinct cytokine profile that may contribute to the polarization of the acquired immune response. Here, we investigated the early MAPK signaling activation via TLR4 and TLR2 receptors and its impact in differential cytokine profile by macrophages. We found that TLR2 ligands activated MAPKs p38 and ERK earlier compared to the TLR4 ligand LPS in macrophages. Higher IL-10/IL-12 and IL-10/TNF-α ratios were also observed at later time points in response to TLR2 ligands compared to LPS. The results also indicate an earlier activation of the phosphatase MKP-1 and that MKP-1 KO macrophages show a prolongation in p38 phosphorylation in response to TLR2 stimulation. Furthermore, p38 is critical for IL-10 expression in response to TLR2 ligands, which triggers the macrophage change to a M2 and regulatory phenotype in contrast to the M1 phenotype induced by TLR4 activation. Therefore, the early TLR2-mediated p38 induction contributes for the high IL-10 production, likely as a virulence strategy to suppress host Th1 response against certain types of pathogens.


Assuntos
Fosfatase 1 de Especificidade Dupla/imunologia , Interleucina-10/imunologia , Macrófagos/imunologia , Receptor 2 Toll-Like/imunologia , Proteínas Quinases p38 Ativadas por Mitógeno/imunologia , Animais , Células Cultivadas , Citocinas/genética , Citocinas/imunologia , Citocinas/metabolismo , Diglicerídeos/farmacologia , Fosfatase 1 de Especificidade Dupla/genética , Fosfatase 1 de Especificidade Dupla/metabolismo , Ativação Enzimática/imunologia , Expressão Gênica/efeitos dos fármacos , Expressão Gênica/imunologia , Interleucina-10/genética , Interleucina-10/metabolismo , Lipopeptídeos/farmacologia , Lipopolissacarídeos/farmacologia , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Oligopeptídeos/farmacologia , Fosforilação/efeitos dos fármacos , Células RAW 264.7 , Receptor 2 Toll-Like/genética , Receptor 2 Toll-Like/metabolismo , Receptor 4 Toll-Like/genética , Receptor 4 Toll-Like/imunologia , Receptor 4 Toll-Like/metabolismo , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
14.
Mitochondrial DNA A DNA Mapp Seq Anal ; 32(4): 115-119, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33576693

RESUMO

Marine fisheries management models have traditionally considered biological parameters and geopolitical boundaries. The result is the existence of fisheries management units that do not match genetic populations. However, this panorama is changing with the contribution of genetic and genomic data. Pagellus bogaraveo is a commercially important sparid in the northeast Atlantic, with three stock components being considered by ICES: the Celtic Sea and Bay of Biscay, Atlantic Iberian waters and the Azores. The northern stock collapsed (1975-1985) and is essential to characterize the genetic makeup of the species, particularly in the Iberian Peninsula, where it is managed as a single stock. The mitochondrial control region was used to screen the intraspecific diversity and population structure of individuals from six locations across the species range. The genetic diversity found is similar among sites, and there is differentiation between the Azores and the remaining locations.


Assuntos
Genética Populacional , Genoma Mitocondrial , Dourada , Animais , DNA Mitocondrial/genética , Pesqueiros , Dourada/genética
15.
Front Immunol ; 12: 748303, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35140704

RESUMO

The Toll-like receptor 4 (TLR4)/myeloid differentiation protein-2 (MD-2) complex is considered the major receptor of the innate immune system to recognize lipopolysaccharides (LPSs). However, some atypical LPSs with different lipid A and core saccharide moiety structures and compositions than the well-studied enterobacterial LPSs can induce a TLR2-dependent response in innate immune cells. Ochrobactrum intermedium, an opportunistic pathogen, presents an atypical LPS. In this study, we found that O. intermedium LPS exhibits a weak inflammatory activity compared to Escherichia coli LPS and, more importantly, is a specific TLR4/TLR2 agonist, able to signal through both receptors. Molecular docking analysis of O. intermedium LPS predicts a favorable formation of a TLR2/TLR4/MD-2 heterodimer complex, which was experimentally confirmed by fluorescence resonance energy transfer (FRET) in cells. Interestingly, the core saccharide plays an important role in this interaction. This study reveals for the first time TLR4/TLR2 heterodimerization that is induced by atypical LPS and may help to escape from recognition by the innate immune system.


Assuntos
Endotoxinas/farmacologia , Lipopolissacarídeos/farmacologia , Receptor 2 Toll-Like/metabolismo , Receptor 4 Toll-Like/metabolismo , Animais , Linhagem Celular , Células HEK293 , Humanos , Imunidade Inata/efeitos dos fármacos , Inflamação/metabolismo , Lipídeo A/farmacologia , Camundongos Endogâmicos C57BL , Camundongos Knockout , Simulação de Acoplamento Molecular
16.
PeerJ ; 9: e11730, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34306828

RESUMO

BACKGROUND: Understanding the interplay between climate and current and historical factors shaping genetic diversity is pivotal to infer changes in marine species range and communities' composition. A phylogeographical break between the Atlantic and the Mediterranean has been documented for several marine organisms, translating into limited dispersal between the two basins. METHODS: In this study, we screened the intraspecific diversity of 150 individuals of the Madeira rockfish (Scorpaena maderensis) across its distributional range (seven sampling locations in the Atlantic and Mediterranean basins) using the mitochondrial control region and the nuclear S7 first intron. RESULTS: The present work is the most comprehensive study done for this species, yielding no genetic structure across sampled locations and no detectable Atlantic-Mediterranean break in connectivity. Our results reveal deep and hyper-diverse bush-like genealogies with large numbers of singletons and very few shared haplotypes. The genetic hyper-diversity found for the Madeira rockfish is relatively uncommon in rocky coastal species, whose dispersal capability is limited by local oceanographic patterns. The effect of climate warming on the distribution of the species is discussed.

17.
PeerJ ; 8: e9098, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32391212

RESUMO

BACKGROUND: Extensive knowledge on the genetic characterization of marine organisms has been assembled, mainly concerning the spatial distribution and structuring of populations. Temporal monitoring assesses not only the stability in genetic composition but also its trajectory over time, providing critical information for the accurate forecast of changes in genetic diversity of marine populations, particularly important for both fisheries and endangered species management. We assessed fluctuations in genetic composition among different sampling periods in the western Portuguese shore in three fish species. METHODS: White seabream Diplodus sargus, sand smelt Atherina presbyter and shanny Lipophrys pholis were chosen, because of their genetic patterns in distinct ecological environments, insight into historical and contemporary factors influencing population effective size (N e ), and degree of commercial exploitation. Samples were obtained near Lisbon between 2003 and 2014 and screened for genetic variation with mitochondrial and nuclear markers. Analyses included genealogies, genetic diversities, temporal structures and contemporary N e . RESULTS: For mtDNA no temporal structure was detected, while for nDNA significant differences were recorded between some sampling periods for the shanny and the sand smelt. Haplotype networks revealed deep genealogies, with various levels of diversification. The shanny revealed a smaller N e /generation when compared to the other species, which, in turn, revealed no evidence of genetic drift for most study periods. These results highlight the fact that temporal variations in genetic pool composition should be considered when evaluating the population structure of fish species with long distance dispersal, which are more vulnerable to recruitment fluctuations.

18.
Sci Rep ; 10(1): 12707, 2020 07 29.
Artigo em Inglês | MEDLINE | ID: mdl-32728141

RESUMO

The displacement of species from equatorial latitudes to temperate locations following the increase in sea surface temperatures is among the significant reported consequences of climate change. Shifts in the distributional ranges of species result in fish communities tropicalisation, i.e., high latitude colonisations by typically low latitude distribution species. These movements create new interactions between species and new trophic assemblages. The Senegal seabream, Diplodus bellottii, may be used as a model to understand the population genetics of these invasions. In the last decades, this species has undergone an outstanding range expansion from its African area of origin to the Atlantic coast of the Iberian Peninsula, where now occurs abundantly. Mitochondrial and nuclear markers revealed a striking high haplotypic nucleotide and genetic diversity values, along with significant population differentiation throughout the present-day geographical range of the Senegal seabream. These results are not consistent with the central-marginal hypothesis, nor with the expectations of a leptokurtic distribution of individuals, as D. bellottii seems to be able to retain exceptional levels of diversity in marginal and recently colonised areas. We discuss possible causes for hyperdiversity and lack of geographical structure and subsequent implications for fisheries.


Assuntos
DNA Mitocondrial/genética , Marcadores Genéticos , Mitocôndrias/genética , Dourada/fisiologia , Animais , Mudança Climática , Europa (Continente) , Variação Genética , Genética Populacional , Haplótipos , Espécies Introduzidas , Mauritânia , Filogeografia , Dinâmica Populacional , Portugal , Dourada/genética , Senegal , Espanha
19.
J Agric Food Chem ; 56(10): 3721-31, 2008 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-18452297

RESUMO

The design, synthesis, and biological evaluation of phosphoramide derivatives as urease inhibitors to reduce the loss of ammonia has been carried out. Forty phosphorus derivatives were synthesized and their inhibitory activities evaluated against that of jack bean urease. In addition, in vivo assays have been carried out. All of the compounds were characterized by IR, (1)H NMR, MS, and elemental microanalysis. In some cases, detailed molecular modeling studies were carried out, and these highlighted the interaction between the enzyme active center and the compounds and also the characteristics related to their activity as urease inhibitors. According to the IC(50) values for in vitro inhibitory activity, 12 compounds showed values below 1 microM and 8 of them represent improvements of activity in comparison to the commercial urease inhibitor N-n-butylthiophosphorictriamide (NBPT) (100 nM) (AGROTAIN). On the basis of the activity results and the conclusions of the molecular modeling study, a structural model for new potential inhibitors has been defined.


Assuntos
Amidas/química , Amidas/farmacologia , Desenho de Fármacos , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/farmacologia , Ácidos Fosfóricos/química , Ácidos Fosfóricos/farmacologia , Urease/antagonistas & inibidores , Sítios de Ligação , Estrutura Molecular , Fosforamidas , Relação Estrutura-Atividade , Urease/química
20.
J Anthropol Sci ; 96: 53-73, 2018 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-30321137

RESUMO

The FLK West sequence is divided into six fluvial stratigraphic levels, each of which provided archaeological materials. In the present paper we outline the major similarities and differences displayed by the lithic assemblages in FLK W, particularly the lower assemblages, which have yielded more objects than the upper ones. The differences noted in the absence-presence and frequency of LCTs may be explained in occupational terms, while the similarities in raw material selection, core reduction and flake retouching patterns indicate homogeneous cultural decisions and cognitive skills. We conclude that these assemblages were likely formed by the same hominin group or taxon and, therefore, the assemblage variability registered would correspond to different expressions of the same economic structure.


Assuntos
Fósseis , Hominidae/fisiologia , Tecnologia/história , Comportamento de Utilização de Ferramentas , Animais , Antropologia Física , História Antiga , Tanzânia
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