442 research outputs found
Dismantling the Beania magellanica (Busk, 1852) species complex (Bryozoa, Cheilostomata): two new species from European waters
New research on bryozoans has determined that formerly widespread species are in many cases complexes of similar, but distinct, species with more restricted distributions. Notwithstanding, the limits of distribution are still unresolved for many taxa, and occasionally a wide distribution is confirmed. Beania magellanica has been considered a widespread species, distributed throughout the Southern Hemisphere, parts of northern Pacific and Atlantic Oceans and the Mediterranean Sea. This study examines the Magellanic-type material, together with other historic samples and new specimens collected in the western Mediterranean and Adriatic, and for the first time, presents specimens from the European North Atlantic. Morphological comparisons and biometric analysis show the existence of three different species among the specimens studied. A redescription of B. magellanica based on the type specimen is presented, and two new species are described: B. serrata sp. nov. from the Northeast Atlantic and B. mediterranea sp. nov. from the Mediterranean Sea. These results indicate that B. magellanica s.l. is a large complex of species and that most specimens from different parts of the world must be revisedThis research was conducted thanks to the funds granted by the Austrian Science Fund (FWF, project number AP28954-B29). The work of Karine Nascimento and Leandro M. Vieira was supported by Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq, project numbers 142058/2015-7 and 422563/2016-1) and by Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES, project number 88881.135517/2016-01). Part of the revision of the samples was supported by the project “Fauna Ibérica: Briozoos II (Familia Cribrilinidae–Familia Watersiporidae)” (CGL2010-22267-C07-02), co-financed by the Ministerio de Economía y Competitividad (Spanish government) and FEDERS
Skeletal muscle specific genes networks in cattle
While physiological differences across skeletal muscles have been described, the differential gene expression underlying them and the discovery of how they interact to perform specific biological processes are largely to be elucidated. The purpose of the present study was, firstly, to profile by cDNA microarrays the differential gene expression between two skeletal muscle types, Psoas major (PM) and Flexor digitorum (FD), in beef cattle and then to interpret the results in the context of a bovine gene coexpression network, detecting possible changes in connectivity across the skeletal muscle system. Eighty four genes were differentially expressed (DE) between muscles. Approximately 54% encoded metabolic enzymes and structural-contractile proteins. DE genes were involved in similar processes and functions, but the proportion of genes in each category varied within each muscle. A correlation matrix was obtained for 61 out of the 84 DE genes from a gene coexpression network. Different groups of coexpression were observed, the largest one having 28 metabolic and contractile genes, up-regulated in PM, and mainly encoding fast-glycolytic fibre structural components and glycolytic enzymes. In FD, genes related to cell support seemed to constitute its identity feature and did not positively correlate to the rest of DE genes in FD. Moreover, changes in connectivity for some DE genes were observed in the different gene ontologies. Our results confirm the existence of a muscle dependent transcription and coexpression pattern and suggest the necessity of integrating different muscle types to perform comprehensive networks for the transcriptional landscape of bovine skeletal muscle
Analyzing the major drivers of NEE in a Mediterranean alpine shrubland
Two years of continuous measurements of net ecosystem exchange (NEE) using the eddy covariance technique were made over a Mediterranean alpine shrubland. This ecosystem was found to be a net source of CO2 (+ 52 ± 7 g C m−2 and + 48 ± 7 g C m−2 for 2007 and 2008) during the two-year study period. To understand the reasons underlying this net release of CO2 into the atmosphere, we analysed the drivers of seasonal variability in NEE over these two years. We observed that the soil water availability – driven by the precipitation pattern – and the photosynthetic photon flux density (PPFD) are the key factors for understanding both the carbon sequestration potential and the duration of the photosynthetic period during the growing season. Finally, the effects of the self-heating correction to CO2 and H2O fluxes measured with the open-path infrared gas analyser were evaluated. Applying the correction turned the annual CO2 budget in 2007 from a sink (− 135 ± 7 g C m−2) to a source (+ 52 ± 7 g C m−2). The magnitude of this change is larger than reported previously and is shown to be due to the low air density and cold temperatures at this high elevation study site.This research was supported by the regional
government Junta de Andalucía, project BACAEMÁ (RNM-332) and the Spanish National flux tower network CARBORED-ES (CGL2006-14195-C02-01/CLI)
Prey choice in insectivorous steppe passerines: New insights from DNA metabarcoding
Food availability plays a key role affecting almost every aspect of bird ecology, including bird population, distribution, reproduction, and behavior. Understanding the functional relationship between prey availability and insectivorous birds’ diet is important in the current scenario of habitat loss and declining of insect and bird populations. We used a fecal metabarcoding approach coupled with prey availability sampling (arthropod abundance and biomass) to test for evidence of selective foraging in a shrub-steppe passerine assemblage over the 2017–2019 breeding seasons in semi-natural steppes of central Spain. The results showed that the six bird species selected specific arthropod taxa. Heteroptera, Orthoptera, Araneae, Lepidoptera and some Coleoptera families were the main selected prey taxa, while Formicidae appeared to be avoided, suggesting that shrub-steppe passerines tend to select prey items providing essential nutrients and energy during the breeding season, while poor quality ones are neglected. Our findings highlight the utility of metabarcoding dietary data to assess prey selection patterns in insectivorous passerines and provide valuable information for the development of conservation and management programs to ensure the long-term availability of crucial food resources for shrub-steppe birds and other insectivores.This study was supported by the European Commission LIFE Ricotí (LIFE15-NAT-ES-000802) and LIFE Connect Ricotí (LIFE20-NAT-ES-000133) projects. This is a contribution to the Excellence Network Remedinal TE-CM (S2013/MAE2719). JG-C is funded by a Margarita Salas Postdoctoral Fellowship (CA4/RSUE/2022-00205) provided by the Spanish Ministry of Universities and Universidad Autónoma de Madrid (Spain)
The Heritability of the Expression of Two Stress-Regulated Gene Fragments in Pigs
Pigs reared in commercial production units sometimes encounter stressors that significantly decrease growth performance. It is hypothesized that response to stress challenges could potentially be used as selection criteria. This study aimed to investigate, in a commercial setting, the heritability of two target genes previously shown to be induced in response to stress, and related to growth performance, in an experimental situation. Blood samples (n = 2,392) were collected from three separate breeding lines of pedigreed and performance-tested boars between 24 to 25 wk of age. The expression levels of a novel fragment, '29a,' and the calcitonin receptor gene (CTR) were quantified using quantitative real-time PCR (qRT-PCR) on a subset (n = 709) of the blood samples. Gene expression levels were corrected for the efficiency of PCR reactions and also computed directly from threshold cycle (Ct) values. Resulting data showed a skewed nonnormal distribution of expression levels for the target genes relative to the endogenous control, glyceraldehyde-3-phosphate dehydrogenase (GAPDH), and were highly variable. Analyses were subsequently performed using untransformed and log-transformed data, with outliers identified and deleted in edited data sets. Regardlessof the transformation or editing procedures for outliers applied, there was negligible genetic variation for the expression of target genes relative to GAPDH. In contrast, repeatabilities of replicate samples were generally high (between 0.54 and 0.67). Absolute expression levels for GAPDH and 29a were lowly heritable (h² ofabout 0.04), although estimates did not exceed their SE. Subsetting the data according to whether the target gene had a higher or lower level of expression than GAPDH was then performed using the relevant Ct values. In the subset where the target gene was more highly expressed than GAPDH, a moderate estimate of heritability (0.18 ± 0.10) for the log-transformed absolute expression level of 29a was obtained, whereas the estimate for its expression relative to GAPDH was lower (0.09 ± 0.07). Estimates of heritability did not increase in the subset of low expression data. The limitations of using gene expression measures as potential selection criteria in commercial situations are discussed
Selecting the best: Interspecific and age-related diet differences among sympatric steppe passerines
Parental food provisioning is crucial for the growth and survival of offspring. Growth rate depends on food quality and food supplied to offspring may differ from what adults use for their own. In the case of steppe passerine birds, detailed characterization on nestling dietary composition, as well as prey choice and resource partitioning among species, is a pending subject. Dietary differences between nestlings and adults remain also largely unexplored. By using faecal DNA metabarcoding, we described the diet of nestlings and adults of five shrub-steppe passerine species over the 2017–2019 breeding seasons in central Spain. We also monitored arthropod availability in the field to assess dietary selection. We expected interspecific dietary differences to limit competition for food resources among sympatric species, as well as parental selection of high quality prey for nestlings. We also predicted age-related differences, with nestlings being fed nutrient-rich prey more frequently than adults. The main arthropod orders provisioned to nestlings were Orthoptera, Julida, Araneae and Lepidoptera. Nestlings of the different species showed high interspecific diet overlap, indicating both a coincidence in growth needs among bird species and no or little limitation of the most profitable resources during the breeding season. Adults of all species showed higher diet richness than nestlings, and age-related differences in prey composition were mainly driven by the selection of the most easily digestible, larger protein- and calcium-rich prey for nestlings, which may favour their rapid growth, and avoiding highly sclerotized and less nutritional prey such as ants. Our study sheds light on the basic ecology and conservation of these declining steppe birds, indicating that interspecific competition may not be a major factor during the breeding season. Given the current global decline of arthropods, further long-term research would be necessary, along with the implementation of effective conservation measures that ensure a sufficient availability of resources identified as key prey in the diet of steppe bird nestlings.This study was supported by the European Commission LIFE Ricotí (LIFE15-NAT-ES-000802) and LIFE Connect Ricotí (LIFE20-NAT-ES-000133) projects. This is a contribution to the Excellence Network Remedinal TE-CM (S2013/MAE2719). JG-C is funded by a Margarita Salas postdoctoral fellowship (CA4/RSUE/2022–00205) provided by the Spanish Ministry of Universities and Universidad Autónoma de Madrid (Spain). CPG acknowledges support from Ministerio de Educación y Formación Profesional through the Beatriz Galindo Fellowship (Beatriz Galindo-Convocatoria 2020) and JZ acknowledges support from Ministerio de Universidades through the predoctoral FPU fellowship program
Using a 3D virtual muscle model to link gene expression changes during myogenesis to protein spatial location in muscle
Background: Myogenesis is an ordered process whereby mononucleated muscle precursor cells (myoblasts) fuse into multinucleated myotubes that eventually differentiate into myofibres, involving substantial changes in gene expression and the organisation of structural components of the cells. To gain further insight into the orchestration of these structural changes we have overlaid the spatial organisation of the protein components of a muscle cell with their gene expression changes during differentiation using a new 3D visualisation tool: the Virtual Muscle 3D (VMus3D)
Bases moleculares de las malformaciones pigmentarias en peces: implicación en el cultivo del rodaballo (Scophthalmus maximus L.)
In mammals the colour of skin is due to production of eumelanins (brown-black pigments) and pheomelanins (yellow-brownish pigments) in a specific type cell, the melanocytes. In contrast, in fish, pigmentation patternare determine by three different types of cells, melanophores, xantophores and iridophores. However, in both cases the melanogenesis is controlled by a similar mechanism. The α-MSH which stimulate the synthesis of melanin, and the ASP which antogonize its effects. Flounder (Scophthalmus maximus L.) agouti gen was cloned from skin tissue by using RACE-PCR with degenerated oligos. High expression of agouti gene was found in white epidermis areas compared with the black ones. Furthermore, dermal-injection of capped agouti mRNA produced a striking skin lightening. Thus, suggesting a central role of agouti gene in pigmentation pattern control in fish
Analysis of gender equality competence present in cultural positions
Articulating the gender dimension in organizations is not easy because their members have to be trained to adopt positions that facilitate the implementation of solutions that help to combat inequalities. The aim of this article was to identify the gender equality competence present in the three types of cultural positions Castells proposed in members of a City Council in Sevilla-Spain, who wanted to implement gender mainstreaming. The participants were 27 people (16 women and 11 men). The method used was discourse analysis. The obtained results show that, while all competences were present in the project position, in the resistance position, there was none. In the legitimizers, we observed inconsistency in the discourse presented. This arouses considerations on the importance of knowing the gender equality competences in order to implement gender mainstreaming in organization
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