Suv39h-catalyzed H3K9me3 is critical for euchromatic genome organization and the maintenance of gene transcription.

H3K9me3-dependent heterochromatin is critical for the silencing of repeat-rich pericentromeric regions and also has key roles in repressing lineage-inappropriate protein-coding genes in differentiation and development. Here, we investigate the molecular consequences of heterochromatin loss in cells deficient in both SUV39H1 and SUV39H2 (Suv39DKO), the major mammalian histone methyltransferase enzymes that catalyze heterochromatic H3K9me3 deposition. We reveal a paradoxical repression of protein-coding genes in Suv39DKO cells, with these differentially expressed genes principally in euchromatic (Tn5-accessible, H3K4me3- and H3K27ac-marked) rather than heterochromatic (H3K9me3-marked) or polycomb (H3K27me3-marked) regions. Examination of the three-dimensional (3D) nucleome reveals that transcriptomic dysregulation occurs in euchromatic regions close to the nuclear periphery in 3D space. Moreover, this transcriptomic dysregulation is highly correlated with altered 3D genome organization in Suv39DKO cells. Together, our results suggest that the nuclear lamina-tethering of Suv39-dependent H3K9me3 domains provides an essential scaffold to support euchromatic genome organization and the maintenance of gene transcription for healthy cellular function.

Understanding how environmental degradation, microclimate, and management shape honey production across different spatial scales.

Although the abundance, survival, and pollination performance of honeybees are sensitive to changes in habitat and climate conditions, the processes by which these effects are transmitted to honey production and interact with beekeeping management are not completely understood. Climate change, habitat degradation, and beekeeping management affect honey yields, and may also interact among themselves resulting in indirect effects across spatial scales. We conducted a 2-year, multi-scale study on Chiloe Island (northern Patagonia), where we evaluated the most relevant environmental and management drivers of honey produced by stationary beekeepers. We found that the effects of microclimate, habitat, and management variables changed with the spatial scale. Among the environmental variables, minimum temperature, and cover of the invasive shrub, gorse (Ulex europaeus) had the strongest detrimental impacts on honey production at spatial scales finer than 4 km. Specialized beekeepers who adopted conventional beekeeping and had more mother colonies were more productive. Mean and minimum temperatures interacted with the percentage of mother colonies, urban cover, and beekeeping income. The gorse cover increased by the combination of high temperatures and the expansion of urban lands, while landscape attributes, such as Eucalyptus plantation cover, influenced beekeeping management. Results suggest that higher temperatures change the available forage or cause thermal stress to honeybees, while invasive shrubs are indicators of degraded habitats. Climate change and habitat degradation are two interrelated environmental phenomena whose effects on beekeeping can be mitigated through adaptive management and habitat restoration.

SMCHD1 has separable roles in chromatin architecture and gene silencing that could be targeted in disease.

The interplay between 3D chromatin architecture and gene silencing is incompletely understood. Here, we report a novel point mutation in the non-canonical SMC protein SMCHD1 that enhances its silencing capacity at endogenous developmental targets. Moreover, it also results in enhanced silencing at the facioscapulohumeral muscular dystrophy associated macrosatellite-array, D4Z4, resulting in enhanced repression of DUX4 encoded by this repeat. Heightened SMCHD1 silencing perturbs developmental Hox gene activation, causing a homeotic transformation in mice. Paradoxically, the mutant SMCHD1 appears to enhance insulation against other epigenetic regulators, including PRC2 and CTCF, while depleting long range chromatin interactions akin to what is observed in the absence of SMCHD1. These data suggest that SMCHD1's role in long range chromatin interactions is not directly linked to gene silencing or insulating the chromatin, refining the model for how the different levels of SMCHD1-mediated chromatin regulation interact to bring about gene silencing in normal development and disease.

Partículas en suspensión PM10, NO2 y agudizaciones de enfermedad respiratoria crónica / Particulate matter PM10, NO2 and exacerbations of chronic respiratory diseases

Objetivos Las nuevas directrices de la Organización Mundial de la Salud recomiendan estudios con exposición simultánea a varios contaminantes atmosféricos. El objetivo principal ha sido conocer la fuerza de la asociación entre diferentes concentraciones de PM10 y NO2 y la agudización de enfermedad respiratoria (AER), en concreto del asma y la enfermedad pulmonar obstructiva crónica. Material y métodos Estudio transversal retrospectivo. La población analizada estuvo compuesta por adultos atendidos en un SUAP en determinados días lag+1 de 2019, siendo los días posteriores a las fechas en las que se registran elevaciones de PM10 por encima del valor límite diario. Se han elaborado 3 índices (1: niveles elevados de PM10 y NO2; 2: nivel elevado de PM10 y nivel bajo de NO2, y 3: niveles bajos de PM10 y NO2) y un modelo de regresión logística para cada uno de ellos, con la AER como variable de resultado, y la adición progresiva de variables de ajuste (sexo, edad, tabaco, índice de Charlson, estación, precipitación, viento y temperatura). Resultado Se analizaron 461 personas, 17 con AER. Los modelos 1 y 2 presentaron valores muy similares en la OR ajustada (4,28 [IC95% 1,05-17]), R2 (0,88) y el área bajo la curva ROC (>0,72). En ambos se mantuvo la significación tras incluir las variables de ajuste, mientras que el modelo 3 solo permitió la precipitación. La inclusión del índice de Charlson y el consumo de tabaco en los 3 modelos suponía la pérdida de la significación de la combinación PM10/NO2 respecto a la AER. Conclusiones Los niveles elevados de PM10 presentan relación con la AER y tienen mayor impacto que el NO2, siendo el consumo de tabaco y las comorbilidades los principales precipitantes de las AER (AU)

Objectives The new World Health Organization guidelines recommend studies with simultaneous exposure to multiple air pollutants. The main objective has been to analyze the strength of the association between different concentrations of PM10 and NO2 and the exacerbation of chronic respiratory diseases (ECRD), specifically asthma and chronic obstructive pulmonary disease. Material and methods Retrospective cross-sectional study. The population analyzed were adults treated in an urgent and primary health care center on certain lag+1 days in 2019. Three indices have been developed (1: high levels of PM10 and NO2; 2: high level of PM10 and low level of NO2, and 3: low levels of PM10 and NO2) and a logistic regression model for each of them, with ECRD as the outcome variable, and the progressive addition of adjustment variables (sex, age, tobacco, Charlson index, season, precipitation, wind and temperature). Results Four hundred and sixty-one people were analyzed, 17 with ECRD. Models 1 and 2 presented very similar values in the adjusted OR (4.28 [95% CI 1.05–17]), R2 (0.88) and the area under the ROC curve (>0.72). In both of them the significance was maintained after including the adjustment variables, while model 3 only allowed the addition of precipitation. The inclusion of the Charlson index and the tobacco consumption in the 3 models implied the loss of statistical significance of the PM10/NO2 combination regarding ECRD. Conclusions High levels of PM10 are related to ECRD and have a greater impact than NO2, with tobacco use and comorbidities being the main precipitants of ECRD (AU)

[Particulate matter PM10, NO2 and exacerbations of chronic respiratory diseases]. / Partículas en suspensión PM10, NO2 y agudizaciones de enfermedad respiratoria crónica.

OBJECTIVES: The new World Health Organization guidelines recommend studies with simultaneous exposure to multiple air pollutants. The main objective has been to analyze the strength of the association between different concentrations of PM10 and NO2 and the exacerbation of chronic respiratory diseases (ECRD), specifically asthma and chronic obstructive pulmonary disease. MATERIAL AND METHODS: Retrospective cross-sectional study. The population analyzed were adults treated in an urgent and primary health care center on certain lag+1 days in 2019. Three indices have been developed (1: high levels of PM10 and NO2; 2: high level of PM10 and low level of NO2, and 3: low levels of PM10 and NO2) and a logistic regression model for each of them, with ECRD as the outcome variable, and the progressive addition of adjustment variables (sex, age, tobacco, Charlson index, season, precipitation, wind and temperature). RESULTS: Four hundred and sixty-one people were analyzed, 17 with ECRD. Models 1 and 2 presented very similar values in the adjusted OR (4.28 [95% CI 1.05-17]), R2 (0.88) and the area under the ROC curve (>0.72). In both of them the significance was maintained after including the adjustment variables, while model 3 only allowed the addition of precipitation. The inclusion of the Charlson index and the tobacco consumption in the 3 models implied the loss of statistical significance of the PM10/NO2 combination regarding ECRD. CONCLUSIONS: High levels of PM10 are related to ECRD and have a greater impact than NO2, with tobacco use and comorbidities being the main precipitants of ECRD.

Maternal SMCHD1 regulates Hox gene expression and patterning in the mouse embryo.

Parents transmit genetic and epigenetic information to their offspring. Maternal effect genes regulate the offspring epigenome to ensure normal development. Here we report that the epigenetic regulator SMCHD1 has a maternal effect on Hox gene expression and skeletal patterning. Maternal SMCHD1, present in the oocyte and preimplantation embryo, prevents precocious activation of Hox genes post-implantation. Without maternal SMCHD1, highly penetrant posterior homeotic transformations occur in the embryo. Hox genes are decorated with Polycomb marks H2AK119ub and H3K27me3 from the oocyte throughout early embryonic development; however, loss of maternal SMCHD1 does not deplete these marks. Therefore, we propose maternal SMCHD1 acts downstream of Polycomb marks to establish a chromatin state necessary for persistent epigenetic silencing and appropriate Hox gene expression later in the developing embryo. This is a striking role for maternal SMCHD1 in long-lived epigenetic effects impacting offspring phenotype.

Multiple environmental drivers for the Patagonian forest-dwelling beetles: Contrasting functional and taxonomic responses across strata and trophic guilds.

Forest disturbances modify microhabitats along the different vertical strata, triggering structural and functional changes in forest-dwelling beetle communities. However, the effects of multiple environmental factors can be complex to detect in ecosystems that offer a broad variety of microhabitats for a great variety of beetle species. This is the case in Patagonian temperate forests, where the use of remote sensing provides an opportunity to evaluate the sensitivity of beetle species to environmental changes. Here, we identified the environmental drivers of forest-dwelling beetle communities in the ground and canopy of 34 north Patagonian-forest landscapes. We analyzed the associations of the taxonomic and functional diversity of five trophic guilds with 30 remote-sensing variables of landscape structure, composition, and disturbances; vegetation and soil properties; and climate and physical variables. Hierarchical clustering analysis was used to identify trophic guilds responding similarly to predictors. Segmented regression analysis was used to evaluate functional redundancy from taxonomic-functional richness relationships. A total of 583 species (23,848 individuals) of beetles were recorded for both strata. The effects of environmental variables were heterogeneous across strata and guilds. Canopy beetles were especially sensitive to early successional conditions, and canopy attributes, but also benefited from the canopy openness. Forest specialists of the ground and canopy responded differently to environmental variables. Ground-dwelling beetles were mostly affected by fires, human modifications, edge closeness, high temperatures, and soil properties, responding weakly to canopy properties. Functional redundancy varied weakly along environmental gradients, being more likely in local communities of ground-dwelling beetles mostly composed of species with overlapping functional roles. Contrasting environmental responses between ground and canopy beetles, as well as among beetles of different trophic guilds, should arise from microhabitats that vary across strata and interact differently with response traits.

BAF complex-mediated chromatin relaxation is required for establishment of X chromosome inactivation.

The process of epigenetic silencing, while fundamentally important, is not yet completely understood. Here we report a replenishable female mouse embryonic stem cell (mESC) system, Xmas, that allows rapid assessment of X chromosome inactivation (XCI), the epigenetic silencing mechanism of one of the two X chromosomes that enables dosage compensation in female mammals. Through a targeted genetic screen in differentiating Xmas mESCs, we reveal that the BAF complex is required to create nucleosome-depleted regions at promoters on the inactive X chromosome during the earliest stages of establishment of XCI. Without this action gene silencing fails. Xmas mESCs provide a tractable model for screen-based approaches that enable the discovery of unknown facets of the female-specific process of XCI and epigenetic silencing more broadly.

Climate-induced tree senescence leads to a transient increase in reproductive success of a large woodpecker species.

Climate change-induced mortality of trees is a concerning phenomenon for global forest ecosystems. The rapid decay and death of long-lived trees can significantly impact forest dynamics, with effects that transmit through ecological networks, becoming more evident in organisms occupying high trophic levels, such as large and specialized woodpecker species. However, understanding how populations of high trophic level species respond to climate change is still a challenge. In this study it was analyzed 32-year data of social groups of the Magellanic Woodpecker (Campephilus magellanicus) in North Patagonia, a region facing increasingly frequent droughts and increased temperatures. A positive trend in the size of woodpecker social groups as a response to climate-induced tree senescence was tested. A causal structural equation model examining climate- tree senescence- woodpecker relationships was used. Increasing nonlinear trends and positive interannual growth rates (>10%) for tree senescence and group size were found. Lowland forest sites had higher levels of tree senescence and more numerous social groups. The causal model supported the positive effect of mean temperature on tree senescence and the positive association of woodpeckers with tree senescence. These results provide evidence of a climate-induced increase in tree senescence that causes an increase in the size of woodpecker social groups. It is suggested that accelerated decay and mortality of trees in the northern Patagonian forests will decrease the stocks of deadwood in the long term, threatening the persistence of this large woodpecker species.

COVID-19, consumer behavior, technology, and society: A literature review and bibliometric analysis.

The COVID-19 crisis is among the most disruptive events in recent decades. Its profound consequences have garnered the interest of many studies in various disciplines, including consumer behavior, thereby warranting an effort to review and systematize the literature. Thus, this study systematizes the knowledge generated by 70 COVID-19 and consumer behavior studies in the Scopus database. It employs descriptive analysis, highlighting the importance of using quantitative methods and China and the US as research settings. Co-occurrence analysis further identified various thematic clusters among the studies. The input-process-output consumer behavior model guided the systematic review, covering several psychological characteristics and consumer behaviors. Accordingly, measures adopted by governments, technology, and social media stand out as external factors. However, revised marketing strategies have been oriented toward counteracting various consumer risks. Hence, given that technological and digital formats mark consumer behavior, firms must incorporate digital transformations in their process.

Tree decay modulates the functional response of lichen communities in Patagonian temperate forests.

Epiphytic and epixylic lichens respond negatively to forest degradation, climate change and pollution, but those effects may depend on functional traits or interact with the stage of tree decay. Disentangling the main drivers of lichen communities remains a challenge in regions where lichens are diverse and poorly known, as the case of Patagonian temperate forests. We used a multi-scale approach to evaluate the relationship between environmental variables, tree decay stage and lichens. We sampled lichens across three increasing scales (tree â‰ª site â‰ª landscape) by selecting 19 landscape units, where trees in four decay stages (snags, logs, cavity trees and healthy trees) were selected within sampling plots. A total of 35 predictors were measured over different scales, including 25 remote sensing indices of forest conditions, climate and air pollutants. Structural Equation Models were used to test the causal linkages of predictors with lichens, distinguishing functional categories (size, growth and reproductive strategy). A total of 69 lichen species were recorded. Cavity trees and logs supported the largest diversity, while snags and healthy trees had the lowest diversity. Functional lichen groups responded differently to fine-scale variables, including the diameter, height, density and pH of trees. Air pollutants affected species with sexual and mixed strategies. Lichens were sensitive to precipitation, temperature and wind speed, with foliose and sexual species responding positively to the latter. The abundance of all species and macrolichens increased with tree senescence and decreased with canopy continuity. Lichens occupying snags and logs responded negatively to primary productivity and tree senescence, but positively to soil organic matter. Our findings suggest: i) the functional structure of lichen communities varies non-linearly with the wood decay process; ii) the reproductive strategy influences the sensitivity to air pollutants, iii) climate variables influence dispersal and colonization of woody substrates; and iv) forest structure/succession interacts with tree decay.

Smchd1 is a maternal effect gene required for genomic imprinting.

Genomic imprinting establishes parental allele-biased expression of a suite of mammalian genes based on parent-of-origin specific epigenetic marks. These marks are under the control of maternal effect proteins supplied in the oocyte. Here we report epigenetic repressor Smchd1 as a novel maternal effect gene that regulates the imprinted expression of ten genes in mice. We also found zygotic SMCHD1 had a dose-dependent effect on the imprinted expression of seven genes. Together, zygotic and maternal SMCHD1 regulate three classic imprinted clusters and eight other genes, including non-canonical imprinted genes. Interestingly, the loss of maternal SMCHD1 does not alter germline DNA methylation imprints pre-implantation or later in gestation. Instead, what appears to unite most imprinted genes sensitive to SMCHD1 is their reliance on polycomb-mediated methylation as germline or secondary imprints, therefore we propose that SMCHD1 acts downstream of polycomb imprints to mediate its function.

Empirical evidence for intransitivity in consumer preferences.

The present paper addresses one of the most important assumptions in consumer preference patterns: transitivity. This assumption states that, logically, selections between goods are rational because of the transitivity statement, which posits that people always prefer goods in the following order: A is preferred to B, and B is preferred to C, so A is preferred to C. With the aim of proving this principle's validity, we conducted an experiment with 70 subjects and probed their preferences in relation to edible and nonedible goods. We used a survey methodology, which allowed us to analyze three distinct situations: 1) individuals faced with goods choices without restrictions; 2) individuals facing budget restrictions and price changes; and 3) individuals faced with decreased disposable income. The results mostly showed that there was no evidence of transitivity in consumer preferences. On average, transitivity appeared in only 8% of the sample, and in cases where transitivity was proved, it was revealed to be strong. The preferences were transitive primarily in relation to edible rather than nonedible goods.

Parochodaeus bituberculatus (Erichson) (Coleoptera: Ochodaeidae) and Faargia gentilii (Martínez) (Coleoptera: Scarabaeidae), two species newly discovered in Chile.

The presence in Chile of scarab beetles (Coleoptera: Scarabaeoidea) described originally from Peru and Argentina have been reported previously, as a result of the distributional corridors through passes in the Andes Mountains (Gutiérrez 1947, 1950; Roig-Juñent et al. 2005; Ruiz-Manzanos 2006; Mondaca 2011). The purpose of this paper is to report the presence of Parochodaeus bituberculatus (Erichson, 1847) (Coleoptera: Ochodaeidae: Ochodaeinae: Ochodaeini) and Faargia gentilii (Martínez, 1975) (Coleoptera: Scarabaeidae: Melolonthinae: Tanyproctini) in Chile, expanding the distribution of the second species to the west of the Andes Mountain range. The presence of both species in Chile is not surprising, due to the similarity of habitats in the collection areas with neighboring localities in Peru and Argentina.

Influence of Storage Conditions and Preservatives on Metabolite Fingerprints in Urine.

Human urine, which is rich in metabolites, provides valuable approaches for biomarker measurement. Maintaining the stability of metabolites in urine is critical for accurate and reliable research results and subsequent interpretation. In this study, the effect of storage temperature (4, 22, and 40 °C), storage time (24 and 48 h), and use of preservatives (boric acid (BA), thymol) and para-aminobenzoic acid (PABA) on urinary metabolites in the pooled urine samples from 20 participants was systematically investigated using large-scale targeted liquid chromatography tandem mass spectrometry (LC-MS/MS)-based metabolomics. Statistical analysis of 158 reliably detected metabolites showed that metabolites in urine with no preservative remained stable at 4 °C for 24 and 48 h as well as at 22 °C for 24 h, but significant metabolite differences were observed in urine stored at 22 °C for 48 h and at 40 °C. The mere addition of BA caused metabolite changes. Thymol was observed to be effective in maintaining metabolite stability in urine in all the conditions designed, most likely due to the inhibitory effect of thymol on urine microbiota. Our results provide valuable urine preservation guidance during sample storage, which is essential for obtaining reliable, accurate, and reproducible analytical results from urine samples.

Pseudoamycle polylepisae gen. et sp. nov., a fulgorid from the highlands of Northern Chile (Hemiptera: Fulgoridae).

Pseudoamycle polylepisae gen. et sp. nov. is described from northernmost Chile (Arica and Parinacota Region). It is characterized by the small and brown body, head with no preocular flange, cephalic process porrect and dorsoventrally compressed, dorsal surface from lateral view not angulate at level of eyes, eyes round, tegmina concolorous and vein MP of tegmen pectinate. The new taxon was found to be associated with Polyepis rugulosa Bitter (Rosaceae).

Avian ecosystem functions are influenced by small mammal ecosystem engineering.

BACKGROUND: Birds are important mobile link species that contribute to landscape-scale patterns by means of pollination, seed dispersal, and predation. Birds are often associated with habitats modified by small mammal ecosystem engineers. We investigated whether birds prefer to forage on degu (Octodon degus) runways by comparing their foraging effort across sites with a range of runway densities, including sites without runways. We measured granivory by granivorous and omnivorous birds at Rinconada de Maipú, central Chile. As a measure of potential bird foraging on insects, we sampled invertebrate prey richness and abundance across the same sites. We then quantified an index of plot-scale functional diversity due to avian foraging at the patch scale. RESULTS: We recorded that birds found food sources sooner and ate more at sites with higher densities of degu runways, cururo mounds, trees, and fewer shrubs. These sites also had higher invertebrate prey richness but lower invertebrate prey abundance. This implies that omnivorous birds, and possibly insectivorous birds, forage for invertebrates in the same plots with high degu runway densities where granivory takes place. In an exploratory analysis we also found that plot-scale functional diversity for four avian ecosystem functions were moderately to weakly correllated to expected ecosystem function outcomes at the plot scale. CONCLUSIONS: Degu ecosystem engineering affects the behavior of avian mobile link species and is thus correlated with ecosystem functioning at relatively small spatial scales.