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Human adenovirus-36 (HAdV-36) infection has been linked to obesity, low lipid levels, and improvements in blood glucose levels and insulin sensitivity in animal models and humans, although epidemiological studies remain controversial. Therefore, this study investigated the relationship between HAdV-36 seropositivity and glycemic control in youths. This observational study examined 460 youths (246 with normal weight and 214 obese subjects). All participants underwent assessments for anthropometry, blood pressure, circulating fasting levels of glucose, lipids, insulin, and anti-HAdV-36 antibodies; additionally, the homeostatic model assessment of insulin resistance (HOMA-IR) was calculated. In all, 57.17% of the subjects were HAdV-36 seropositive. Moreover, HAdV-36 seroprevalence was higher in obese subjects compared to their normal weight counterparts (59% vs. 55%). BMI (33.1 vs. 32.3 kg/m2, p = 0.03), and waist circumference (107 vs. 104 cm, p = 0.02), insulin levels (21 vs. 16.3 µU/mL, p = 0.003), and HOMA-IR (4.6 vs. 3.9, p = 0.02) were higher in HAdV-36-positive subjects with obesity compared to seronegative subjects. In the obese group, HAdV-36 seropositivity was associated with a reducing effect in blood glucose levels in a model adjusted for total cholesterol, triglyceride levels, age and sex (ß = -10.44, p = 0.014). Furthermore, a statistically significant positive relationship was observed between HAdV-36 seropositivity and insulin levels in the obesity group. These findings suggest that natural HAdV-36 infection improves glycemic control but does not ameliorate hyperinsulinemia in obese subjects.
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Infecciones por Adenovirus Humanos , Adenovirus Humanos , Glucemia , Resistencia a la Insulina , Insulina , Obesidad , Humanos , Masculino , Femenino , Glucemia/análisis , Insulina/sangre , Adolescente , Obesidad/sangre , Infecciones por Adenovirus Humanos/sangre , Infecciones por Adenovirus Humanos/epidemiología , Infecciones por Adenovirus Humanos/virología , Niño , Estudios Seroepidemiológicos , Adulto Joven , Índice de Masa Corporal , Anticuerpos Antivirales/sangreRESUMEN
Dorper rams (n = 24) were evaluated during the sexual resting season to determine their social rank (SR), either high (HSR) or low (LSR), under intensive management conditions in northern Mexico (25° N). Aggressive behaviors were quantified during male-to-male interactions, and appetitive and consummatory sexual behaviors during male-to-female interactions. Morphometric, live weight (LW), and body condition score (BCS) were recorded. During the early reproductive season, male-to-female behaviors were newly itemized simultaneously by seminal quality and quantity sampling. Finally, the dependent variables of the hemogram components were also quantified. Neither LW (61.25 ± 2.4 kg) nor morphometric variables differed between SR groups. However, BCS (2.25 vs. 2.66 u), sexual behaviors (i.e., approaches: 59.6 vs. 21.73 n, mating with ejaculation: 77.7 vs. 42.86 %, latency to ejaculation: 16.6 vs. 143.07 s), ejaculate volume (0.57 vs. 0.23 mL), and hemogram components favored the HSR rams (p < 0.05). Moreover, in their first male-to-female interaction, >50% of the LSR rams failed to display any sexual activity. HSR rams displayed a greater number of threatening behaviors, managing to displace LSR rams when exposed to estrus ewes during the male sexual resting season; more sexual behaviors; and an increased seminal volume in a non-live weight-dependent fashion.
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It is well established that human adenoviruses such as species C, types 2 and 5 (HAdV-C2 and HAdV-C5), induce a nearly complete shutoff of host-cell protein synthesis in the infected cell, simultaneously directing very efficient production of viral proteins. Such preferential expression of viral over cellular genes is thought to be controlled by selective nucleocytoplasmic export and translation of viral mRNA. While detailed knowledge of the regulatory mechanisms responsible for the translation of viral mRNA is available, the viral or cellular mechanisms of mRNA biogenesis are not completely understood. To identify parameters that control the differential export of viral and cellular mRNAs, we performed global transcriptome analyses (RNAseq) and monitored temporal nucleocytoplasmic partitioning of viral and cellular mRNAs during HAdV-C5 infection of A549 cells. Our analyses confirmed previously reported features of the viral mRNA expression program, as a clear shift in viral early to late mRNA accumulation was observed upon transition from the early to the late phase of viral replication. The progression into the late phase of infection, however, did not result in abrogation of cellular mRNA export; rather, viral late mRNAs outnumbered viral early and most cellular mRNAs by several orders of magnitude during the late phase, revealing that viral late mRNAs are not selectively exported but outcompete cellular mRNA biogenesis.
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Adenovirus Humanos , Humanos , ARN Mensajero/genética , ARN Mensajero/metabolismo , Adenovirus Humanos/genética , Adenovirus Humanos/metabolismo , Replicación Viral , Proteínas Virales/genética , Perfilación de la Expresión Génica , ARN Viral/genética , ARN Viral/metabolismoRESUMEN
Human adenovirus 36 (HAdV-D36) can cause obesity in animal models, induces an adipogenic effect and increased adipocyte differentiation in cell culture. HAdV-D36 infection alters gene expression and the metabolism of the infected cells resulting in increased glucose internalization and triglyceride accumulation. Although HAdV-D36 prevalence correlates with obesity in humans, whether human preadipocytes may be targeted in vivo has not been determined and metabolic reprogramming of preadipocytes has not been explored in the context of the viral replication cycle. HAdV-D36 infection of the mouse fibroblasts, 3T3-L1 cells, which can differentiate into adipocytes, promotes proliferation and differentiation, but replication of the virus in these cells is abortive as indicated by short-lived transient expression of viral mRNA and a progressive loss of viral DNA. Therefore, we have evaluated whether a productive viral replication cycle can be established in the 3T3-L1 preadipocyte model under conditions that drive the cell differentiation process. For this purpose, viral mRNA levels and viral DNA replication were measured by RT-qPCR and qPCR, respectively, and viral progeny production was determined by plaque assay. The lipogenic effect of infection was evaluated with Oil Red O (ORO) staining, and expression of genes that control lipid and glucose metabolism was measured by RT-qPCR. In the context of a viral productive cycle, HAdV-D36 modulated the expression of the adipogenic genes, C/EBPα, C/EBPß and PPARγ, as well as intracellular lipid accumulation, and the infection was accompanied by altered expression of glucolytic genes. The results show that only adipocyte-committed 3T3-L1 cells are permissive for the expression of early and late viral mRNAs, as well as viral DNA replication and progeny production, supporting productive HAdV-D36 viral replication, indicating that a greater effect on adipogenesis occurs in adipocytes that support productive viral replication.
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Infecciones por Adenovirus Humanos , Adenovirus Humanos , Células 3T3-L1 , Adenovirus Humanos/genética , Adipocitos , Animales , Diferenciación Celular , Replicación del ADN , ADN Viral , Glucosa/metabolismo , Humanos , Metabolismo de los Lípidos , Lípidos/farmacología , Ratones , Obesidad , PPAR gamma/genética , PPAR gamma/metabolismo , PPAR gamma/farmacología , ARN Mensajero/metabolismo , Triglicéridos/metabolismo , Replicación ViralRESUMEN
The acequias de careo are ancestral water channels excavated during the early Al-Andalus period (8th-10th centuries), which are used to recharge aquifers in the watersheds of the Sierra Nevada mountain range (Southeastern Spain). The water channels are maintained by local communities, and their main function is collecting snowmelt, but also runoff from rainfall from the headwaters of river basins and distributing it throughout the upper parts of the slopes. This method of aquifer artificial recharge extends the availability of water resources in the lowlands of the river basins during the dry season when there is almost no precipitation and water demand is higher. This study investigates the contribution of the careo channels in the watershed of Bérchules concerning the total aquifer recharge during the 2014-2015 hydrological year. Several channels were gauged, and the runoff data were compared with those obtained from a semi-distributed hydrological model applied to the same hydrological basin. The natural infiltration of meteoric waters accounted for 52% of the total recharge, while the remaining 48% corresponded to water transported and infiltrated by the careo channels. In other words, the careo recharge system enhances by 92% the natural recharge to the aquifer. Our results demonstrate the importance of this ancestral and efficient channel system for recharging slope aquifers developed in hard rocks. The acequias de careo are nature-based solutions for increasing water resources availability that have contributed to a prosperous life in the Sierra Nevada. Its long history (>1200 years) suggests that the system has remarkable resilience properties, which have allowed adaptation and permance for centuries in drastically changing climatic and socioeconomic conditions. This recharge system could also be applied to -or inspire similar adaptation measures in- semi-arid mountain areas around the world where it may help in mitigating climate change effects.
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Agua Subterránea , Hidrología , Ríos , España , AguaRESUMEN
The multifunctional adenoviral E1B-55K phosphoprotein is a major regulator of viral replication and plays key roles in virus-mediated cell transformation. While much is known about its function in oncogenic cell transformation, the underlying features and exact mechanisms that implicate E1B-55K in the regulation of viral gene expression are less well understood. Therefore, this work aimed to unravel basic intranuclear principles of E1B-55K-regulated viral mRNA biogenesis using wild-type human adenovirus C5 (HAdV-C5) E1B-55K, a virus mutant with abrogated E1B-55K expression, and a mutant that expresses a phosphomimetic E1B-55K. By subnuclear fractionation, mRNA, DNA, and protein analyses as well as luciferase reporter assays, we show that (i) E1B-55K promotes the efficient release of viral late mRNAs from their site of synthesis in viral replication compartments (RCs) to the surrounding nucleoplasm, (ii) E1B-55K modulates the rate of viral gene transcription and splicing in RCs, (iii) E1B-55K participates in the temporal regulation of viral gene expression, (iv) E1B-55K can enhance or repress the expression of viral early and late promoters, and (v) the phosphorylation of E1B-55K regulates the temporal effect of the protein on each of these activities. Together, these data demonstrate that E1B-55K is a phosphorylation-dependent transcriptional and posttranscriptional regulator of viral genes during HAdV-C5 infection. IMPORTANCE Human adenoviruses are useful models to study basic aspects of gene expression and splicing. Moreover, they are one of the most commonly used viral vectors for clinical applications. However, key aspects of the activities of essential viral proteins that are commonly modified in adenoviral vectors have not been fully described. A prominent example is the multifunctional adenoviral oncoprotein E1B-55K that is known to promote efficient viral genome replication and expression while simultaneously repressing host gene expression and antiviral host responses. Our study combined different quantitative methods to study how E1B-55K promotes viral mRNA biogenesis. The data presented here propose a novel role for E1B-55K as a phosphorylation-dependent transcriptional and posttranscriptional regulator of viral genes.
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Infecciones por Adenovirus Humanos , Adenovirus Humanos , Transformación Celular Viral , Regulación Viral de la Expresión Génica , Proteínas Virales , Infecciones por Adenovirus Humanos/fisiopatología , Infecciones por Adenovirus Humanos/virología , Adenovirus Humanos/genética , Adenovirus Humanos/metabolismo , Transformación Celular Viral/genética , Humanos , Fosforilación , ARN Mensajero/genética , ARN Mensajero/metabolismo , Proteínas Virales/metabolismoRESUMEN
A common viral replication strategy is characterized by the assembly of intracellular compartments that concentrate factors needed for viral replication and simultaneously conceal the viral genome from host-defense mechanisms. Recently, various membrane-less virus-induced compartments and cellular organelles have been shown to represent biomolecular condensates (BMCs) that assemble through liquid-liquid phase separation (LLPS). In the present work, we analyze biophysical properties of intranuclear replication compartments (RCs) induced during human adenovirus (HAdV) infection. The viral ssDNA-binding protein (DBP) is a major component of RCs that contains intrinsically disordered and low complexity proline-rich regions, features shared with proteins that drive phase transitions. Using fluorescence recovery after photobleaching (FRAP) and time-lapse studies in living HAdV-infected cells, we show that DBP-positive RCs display properties of liquid BMCs, which can fuse and divide, and eventually form an intranuclear mesh with less fluid-like features. Moreover, the transient expression of DBP recapitulates the assembly and liquid-like properties of RCs in HAdV-infected cells. These results are of relevance as they indicate that DBP may be a scaffold protein for the assembly of HAdV-RCs and should contribute to future studies on the role of BMCs in virus-host cell interactions.
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Adenoviridae/metabolismo , Condensados Biomoleculares , Proteínas de Unión al ADN/metabolismo , Compartimentos de Replicación Viral/fisiología , Replicación Viral/fisiología , Adenoviridae/genética , Infecciones por Adenoviridae , Adenovirus Humanos/metabolismo , Línea Celular , Proteínas de Unión al ADN/química , Interacciones Microbiota-Huesped , Humanos , Orgánulos/virología , Dominios Proteicos , Proteínas Virales/química , Proteínas Virales/genética , Proteínas Virales/metabolismoRESUMEN
Coronaviruses (CoV) are enveloped, plus-strand RNA viruses that have the largest known RNA genomes and infect birds and mammals, causing various diseases. Human coronaviruses (HCoVs) were first identified in the mid-1960s and have been known to cause enteric or respiratory infections. In the last two decades, three HCoVs have emerged, including the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which initiated the ongoing pandemic. SARS-CoV-2 causes a respiratory illness that presents as a mild upper respiratory disease but may result in acute respiratory distress syndrome, multi-organ failure and can be fatal, especially when underlying comorbidities are present. Children account for a low percentage of coronavirus disease 2019 (COVID-19) cases, with seemingly less severe disease. Most pediatric patients present mild or moderate symptoms or are asymptomatic. However, some cases may be severe. Therefore, SARS-CoV-2 infection and COVID-19 in pediatric patients must be studied in detail. This review describes general features of the molecular biology of CoVs and virus-host interactions that may be implicated in the pathogenesis of SARS-CoV-2.
Los coronavirus son virus envueltos de ARN de polaridad positiva, con los genomas más grandes que se conocen. Infectan aves y mamíferos, y causan una amplia variedad de enfermedades. Los coronavirus humanos se identificaron a mediados de la década de 1960 y se sabe que causan infecciones entéricas y respiratorias. En las últimas dos décadas han emergido tres coronavirus humanos pandémicos, incluido el coronavirus 2 del síndrome agudo respiratorio grave (SARS-CoV-2) que ha causado la pandemia actual. El SARS-CoV-2 produce enfermedad respiratoria que se presenta con padecimientos moderados de las vías respiratorias altas, pero puede resultar en síndrome respiratorio agudo, falla multiorgánica y muerte, en especial en casos con morbilidad subyacente. Los casos de COVID-19 en niños representan un porcentaje bajo y con síntomas menos graves de la enfermedad. La mayoría de los pacientes pediátricos son asintomáticos o presentan enfermedad leve o moderada; sin embargo, también en niños la enfermedad puede ser grave, por lo que la infección con SARS-CoV-2 y la COVID-19 en pacientes pediátricos deben estudiarse con detalle. En esta revisión se describen las características generales de la biología molecular de los coronavirus y de las interacciones virus-hospedero que se conocen para los coronavirus humanos identificados previamente, y que podrían estar implicados en la patogénesis del SARS-CoV-2.
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COVID-19/virología , Infecciones por Coronavirus/virología , Coronavirus/genética , Animales , COVID-19/epidemiología , Niño , Coronavirus/clasificación , Coronavirus/aislamiento & purificación , Infecciones por Coronavirus/clasificación , Infecciones por Coronavirus/epidemiología , Humanos , SARS-CoV-2/genética , SARS-CoV-2/aislamiento & purificación , Índice de Severidad de la EnfermedadRESUMEN
BACKGROUND: Human adenovirus 36 (HAd36) infection has been associated with obesity. Experiments using 3T3-L1 adipocyte cultured cells and human adipose stem cells (hASCc) have shown that HAd36 stimulates the expression of genes implicated in cell differentiation and increased lipid accumulation. The presence of HAd36 in adipose tissue of overweight and obese women has also been confirmed. This study aims to analyze the presence of HAd36 DNA in the adipose tissue of women undergoing surgery for weight reduction and its relationship with obesity through changes in adipocyte morphology as well as the expression of C/EBPß and HIF-1α. METHODS: Fifty-two subcutaneous adipose tissue biopsies were collected. The anthropometric parameters measured were weight, height, skin folds, body circumferences, and body fat percentage. Biochemical measures were performed for glucose, cholesterol, triglycerides, cholesterol HDL-c, and LDL-c. The presence of HAd36 DNA was performed by conventional PCR. Adipocyte morphology was analyzed in H&E-stained sections using ImageJ/Fiji software. The expression of genes C/EBPß, HIF-1α and ß-actin was determined using TaqMan probes. RESULTS: HAd36 DNA was detected in 31% of adipose tissue samples. The presence of viral DNA was not significantly associated with anthropometric, clinical, or metabolic measurements, or with changes in adipose tissue morphology. The levels of mRNA expression for C/EBPß and HIF-1α did not show significant differences between positive and negative samples for HAd36 (p>0.05). CONCLUSION: The presence of HAd36 DNA in adipose tissue was identified, but it was not related to morphological changes of adipocytes, or the expression of C/EBPß and HIF-1α. Further studies are needed to confirm these findings.
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Abstract Coronaviruses (CoV) are enveloped, plus-strand RNA viruses that have the largest known RNA genomes and infect birds and mammals, causing various diseases. Human coronaviruses (HCoVs) were first identified in the mid-1960s and have been known to cause enteric or respiratory infections. In the last two decades, three HCoVs have emerged, including the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which initiated the ongoing pandemic. SARS-CoV-2 causes a respiratory illness that presents as a mild upper respiratory disease but may result in acute respiratory distress syndrome, multi-organ failure and can be fatal, especially when underlying comorbidities are present. Children account for a low percentage of coronavirus disease 2019 (COVID-19) cases, with seemingly less severe disease. Most pediatric patients present mild or moderate symptoms or are asymptomatic. However, some cases may be severe. Therefore, SARS-CoV-2 infection and COVID-19 in pediatric patients must be studied in detail. This review describes general features of the molecular biology of CoVs and virus-host interactions that may be implicated in the pathogenesis of SARS-CoV-2.
Resumen Los coronavirus son virus envueltos de ARN de polaridad positiva, con los genomas más grandes que se conocen. Infectan aves y mamíferos, y causan una amplia variedad de enfermedades. Los coronavirus humanos se identificaron a mediados de la década de 1960 y se sabe que causan infecciones entéricas y respiratorias. En las últimas dos décadas han emergido tres coronavirus humanos pandémicos, incluido el coronavirus 2 del síndrome agudo respiratorio grave (SARS-CoV-2) que ha causado la pandemia actual. El SARS-CoV-2 produce enfermedad respiratoria que se presenta con padecimientos moderados de las vías respiratorias altas, pero puede resultar en síndrome respiratorio agudo, falla multiorgánica y muerte, en especial en casos con morbilidad subyacente. Los casos de COVID-19 en niños representan un porcentaje bajo y con síntomas menos graves de la enfermedad. La mayoría de los pacientes pediátricos son asintomáticos o presentan enfermedad leve o moderada; sin embargo, también en niños la enfermedad puede ser grave, por lo que la infección con SARS-CoV-2 y la COVID-19 en pacientes pediátricos deben estudiarse con detalle. En esta revisión se describen las características generales de la biología molecular de los coronavirus y de las interacciones virus-hospedero que se conocen para los coronavirus humanos identificados previamente, y que podrían estar implicados en la patogénesis del SARS-CoV-2.
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Animales , Niño , Humanos , Infecciones por Coronavirus/virología , Coronavirus/genética , COVID-19/virología , Índice de Severidad de la Enfermedad , Infecciones por Coronavirus/clasificación , Infecciones por Coronavirus/epidemiología , Coronavirus/aislamiento & purificación , Coronavirus/clasificación , SARS-CoV-2/aislamiento & purificación , SARS-CoV-2/genética , COVID-19/epidemiologíaRESUMEN
Time series of environmental tracers (groundwater stable isotope composition, electrical conductivity and temperature) and concentration breakthrough curves of artificial tracers (uranine, eosine, amino-G and naphtionate) have been analyzed to characterize fast preferential and slow matrix in-transit recharge flows in the Paleocene-Eocene limestone aquifer of the Ordesa and Monte Perdido National Park, an alpine karst system drained by a water table cave, a rare hydrological feature in high mountain karst systems with similar characteristics. Snowmelt favors the areal recharge of the system. This process is reflected in the large proportion of groundwater flowing through the connected porosity structure of the karst aquifer, which amounts the 75% of the total system water discharge. From the perspective of water resources recovery, the water capacity of the fissured-porous zone (matrix) represents 99% of the total karst system storage. The volume associated to the karst conduits is very small. The estimated mean travel times are 9â¯days for conduits and 475â¯days for connected porosity. These short travel times reveal high vulnerability of the karst system to pollutants in broad sense and a great impact of climate change on the associated water resources.
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Viruses are the most abundant biological entities in the biosphere, and have the ability to infect Bacteria, Archaea, and Eukaryotes. The virome is estimated to be at least ten times more abundant than the microbiome with 107 viruses per milliliter and 109 viral particles per gram in marine waters and sediments or soils, respectively. Viruses represent a largely unexplored genetic diversity, having an important role in the genomic plasticity of their hosts. Moreover, they also play a significant role in the dynamics of microbial populations. In recent years, metagenomic approaches have gained increasing popularity in the study of environmental viromes, offering the possibility of extending our knowledge related to both virus diversity and their functional characterization. Extreme environments represent an interesting source of both microbiota and their virome due to their particular physicochemical conditions, such as very high or very low temperatures and >1 atm hydrostatic pressures, among others. Despite the fact that some progress has been made in our understanding of the ecology of the microbiota in these habitats, few metagenomic studies have described the viromes present in extreme ecosystems. Thus, limited advances have been made in our understanding of the virus community structure in extremophilic ecosystems, as well as in their biotechnological potential. In this review, we critically analyze recent progress in metagenomic based approaches to explore the viromes in extreme environments and we discuss the potential for new discoveries, as well as methodological challenges and perspectives.
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The adenovirus E1B 55K (E1B) protein plays major roles in productive adenoviral infection and cellular transformation. Interest in E1B increased because of the potential of adenoviruses as therapeutic vectors, and the E1B gene is commonly deleted from adenovirus vectors for anticancer therapy. E1B activities are spatiotemporally regulated through SUMOylation and phosphorylation, and through interactions with multiple partners that occur presumably at different intracellular sites and times postinfection. E1B is implicated in the formation of viral replication compartments and regulates viral genome replication and transcription, transcriptional repression, degradation of cellular proteins, and several intranuclear steps of viral late mRNA biogenesis. Here, we review advances in our understanding of E1B during productive adenovirus replication and discuss fundamental aspects that remain unresolved.
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Adenoviridae/fisiología , Proteínas E1B de Adenovirus/química , Proteínas E1B de Adenovirus/metabolismo , Adenoviridae/metabolismo , Regulación Viral de la Expresión Génica , Modelos Moleculares , Fosforilación , Conformación Proteica , Sumoilación , Replicación ViralRESUMEN
Adenoviruses induce an extensive reorganization of the host cell nucleus during replication. Such a process results in the assembly of viral and cellular macromolecules into nuclear structures called adenovirus replication compartments (AdRCs), which function as platforms for viral DNA replication and gene expression. AdRCs co-opt host proteins and cellular pathways that restrict viral replication, suggesting that the mechanisms that control AdRC formation and function are essential for viral replication and lay at the basis of virus-host interactions. Here, we review the hallmarks of AdRCs and recent progress in our understanding of the formation, composition, and function of AdRCs. Furthermore, we discuss how AdRCs facilitate the interplay between viral and cellular machineries and hijack cellular functions to promote viral genome replication and expression.
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Infecciones por Adenoviridae/virología , Adenoviridae/fisiología , ADN Viral/genética , Adenoviridae/genética , Infecciones por Adenoviridae/metabolismo , Animales , Núcleo Celular/metabolismo , Citoplasma/metabolismo , Regulación Viral de la Expresión Génica , Interacciones Huésped-Patógeno , Humanos , Proteínas Virales/genética , Replicación ViralRESUMEN
The E1B 55kDa produced by human adenovirus type 5 is a multifunctional protein that participates in the regulation of several steps during the viral replication cycle. Previous studies suggest this protein plays an important role in postranscriptional regulation of viral and cellular gene expression, as it is required for the selective accumulation of maximal levels of viral late mRNA in the cytoplasm of the infected cell; however the molecular mechanisms that are altered or regulated by this protein have not been elucidated. A ribonucleoprotein motif that could implicate the direct interaction of the protein with RNA was initially predicted and tested in vitro, but the interaction with RNA could not be detected in infected cells, suggesting the interaction may be weak or transient. Here it was determined that the E1B 55kDa interacts with RNA in the context of the viral infection in non-transformed human cells, and its contribution to the adenovirus replication cycle was evaluated. Using recombinant adenoviruses with amino acid substitutions or a deletion in the ribonucleoprotein motif the interaction of E1B 55kDa with RNA was found to correlate with timely and efficient viral DNA replication and viral late mRNA accumulation and splicing.
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Proteínas E1B de Adenovirus/metabolismo , Adenovirus Humanos/fisiología , ARN Viral/metabolismo , Replicación Viral/fisiología , Proteínas E1B de Adenovirus/genética , Adenovirus Humanos/genética , Línea Celular , Humanos , ARN Viral/genética , Replicación Viral/genéticaRESUMEN
Certain viral infections are known to modify the glycosylation profile of infected cells through the overexpression of specific host cell fucosyltransferases (FUTs). Infection with CMV (cytomegalovirus), HCV (hepatitis C virus), HSV-1 (herpes simplex virus type-1) and VZV (varicella-zoster virus) increase the expression of fucosylated epitopes, including antigens sLex (Siaα2-3 Galß1-4(Fucα1-3)GlcNAcß1-R) and Ley (Fucα1-2 Galß1-4(Fucα1-3)GlcNAcß1-R). The reorganization of the glycocalyx induced by viral infection may favor the spread of viral progeny, and alter diverse biological functions mediated by glycans, including recognition by the adaptive immune system. In this work, we aimed to establish whether infection with human adenovirus type 5 (HAd5), a well-known viral vector and infectious agent, causes changes in the glycosylation profile of A549 cells, used as a model of lung epithelium, a natural target of HAd5. We demonstrate for the first time that HAd5 infection causes a significant increase in the cell surface de novo fucosylation, as assessed by metabolic labeling, and that such modification is dependent on the expression of viral genes. The main type of increased fucosylation was determined to be in α1-2 linkage, as assessed by UEA-I lectin binding and supported by the overexpression of FUT1 and FUT2. Also, HAd5-infected cells showed a heterogeneous change in the expression profile of the bi-fucosylated Ley antigen, an antigen associated with enhanced cell proliferation and inhibition of apoptosis.
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Adenovirus Humanos/inmunología , Adenovirus Humanos/fisiología , Fucosa/metabolismo , Antígenos del Grupo Sanguíneo de Lewis/genética , Células A549 , Humanos , Antígenos del Grupo Sanguíneo de Lewis/inmunología , Antígenos del Grupo Sanguíneo de Lewis/metabolismoRESUMEN
The use of latency reversing agents (LRAs) is currently a promising approach to eliminate latent reservoirs of HIV-1. However, this strategy has not been successful in vivo. It has been proposed that cellular post-transcriptional mechanisms are implicated in the underperformance of LRAs, but it is not clear whether proviral regulatory elements like viral non-coding RNAs (vncRNAs) are also implicated. In order to visualize the complexity of the HIV-1 gene expression, we used experimental data to construct a gene regulatory network (GRN) of latent proviruses in resting CD4+ T cells. We then analyzed the dynamics of this GRN using Boolean and continuous mathematical models. Our simulations predict that vncRNAs are able to counteract the activity of LRAs, which may explain the failure of these compounds to reactivate latent reservoirs of HIV-1. Moreover, our results also predict that using inhibitors of histone methyltransferases, such as chaetocin, together with releasers of the positive transcription elongation factor (P-TEFb), like JQ1, may increase proviral reactivation despite self-repressive effects of vncRNAs.
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In many of the alpine watersheds of Sierra Nevada (Southern Spain) exists an ancient network of dug canals that collect, transport and facilitate the recharge the snowmelt in the underlying aquifer during the spring season. This practice, known as careos, in the lower part of the watersheds supply drinking water as spring discharge during the dry season. To study how this managed recharge technique modifies the natural response of these basins this work focuses on characterizing the hydrological behavior of one of the sites, the Berchules watershed. The mechanisms for mineralization of groundwater are based on geochemical processes such as evapo-concentration in the soil layer and silicate mineral weathering due to dissolved CO2 originated from both soil biogenic processes and the atmosphere. Groundwater presents a main hydrogeochemical calciummagnesium-bicarbonate type facies, which is associated to groundwater flowing through the upper weathered silicates and quickly drained through springs located in the uplands and in the intermediate altitude catchment zone. Additionally, in the lower part of the basin some springs discharge mineralized groundwater with a sodium-calcium-bicarbonate composition associated to regional groundwater flow. In natural conditions, this hydrogeological system behaves as a sloping aquifer, occurring recharge between 1400 and 2500â¯mâ¯a.s.l. The springs discharge groundwater with an isotopic content and temperature in coherence with the local rainfall isotopic and thermal atmospheric altitudinal lines. Nevertheless, once the careo recharge begins the affected springs reveal the fingerprint of the concentrated recharge system by blurring the fingerprint of both the isotopic and thermal altitudinal dependence in the springs discharge. This validates the previous conceptual model and supports average recharge values of 141⯱â¯140â¯mm/yr and total average water resources of 181⯱â¯111â¯mm/yr which include a 40% increase in the study period due to the effect of the acequias de careo.
RESUMEN
Assessing water resources in high mountain semi-arid zones is essential to be able to manage and plan the use of these resources downstream where they are used. However, it is not easy to manage an unknown resource, a situation that is common in the vast majority of high mountain hydrological basins. In the present work, the discharge flow in an ungauged basin is estimated using the hydrological parameters of an HBV (Hydrologiska Byråns Vattenbalansavdelning) model calibrated in a "neighboring gauged basin". The results of the hydrological simulation obtained in terms of average annual discharge are validated using the VI-ETo model. This model relates a simple hydrological balance to the discharge of the basin with the evaporation of the vegetal cover of the soil, and this to the SAVI index, which is obtained remotely by means of satellite images. The results of the modeling for both basins underscore the role of the underground discharge in the total discharge of the hydrological system. This is the result of the deglaciation process suffered by the high mountain areas of the Mediterranean arc. This process increases the infiltration capacity of the terrain, the recharge and therefore the discharge of the aquifers that make up the glacial and periglacial sediments that remain exposed on the surface as witnesses of what was the last glaciation.
RESUMEN
Viruses employ a variety of strategies to hijack cellular activities through the orchestrated recruitment of macromolecules to specific virus-induced cellular micro-environments. Adenoviruses (Ad) and other DNA viruses induce extensive reorganization of the cell nucleus and formation of nuclear Replication Compartments (RCs), where the viral genome is replicated and expressed. In this work an automatic algorithm designed for detection and segmentation of RCs using ellipses is presented. Unlike algorithms available in the literature, this approach is deterministic, automatic, and can adjust multiple RCs using ellipses. The proposed algorithm is non iterative, computationally efficient and is invariant to affine transformations. The method was validated over both synthetic images and more than 400 real images of Ad-infected cells at various timepoints of the viral replication cycle obtaining relevant information about the biogenesis of adenoviral RCs. As proof of concept the algorithm was then used to quantitatively compare RCs in cells infected with the adenovirus wild type or an adenovirus mutant that is null for expression of a viral protein that is known to affect activities associated with RCs that result in deficient viral progeny production.