Calcium-mediated transductive systems and functionally active gap junctions in astrocyte-like GL15 cells

Background  

It has been proposed that GL15, a human cell line derived from glioblastoma multiforme, is a possible astroglial-like cell model, based on the presence of cytoplasmic glial fibrillary acidic protein.     

Sugary vs salty food industry leftovers in postweaning piglets: effects on gut microbiota and intestinal volatile fatty acid production

Awareness of the need to improve the sustainability of livestock by reducing the loss of natural resources has increased significantly. This study investigated the effects of two categories of food industry leftovers, also referred to as former foodstuff products (FFPs), on pig gut microbiota and intestinal volatile fatty acid (VFA) production. Thirty-six female postweaning piglets (28 days old, Large White × Landrace, 6.5 ± 1.1 kg) were separated into three groups and fed a conventional diet (CTR), and diets in which cereals were partially replaced (30% w/w) by sugary confectionery products (FFPs-C) or salty bakery products (FFPs-B), respectively. After 42 days of dietary treatments, faeces were collected from the rectal ampulla, snap-frozen, and used for next-generation sequencing to analyse the composition and the alpha and beta diversity indexes of the microbial population. The concentration of VFAs in the intestinal content collected at the slaughterhouse was also analysed. The study demonstrated that balanced diets can be obtained by the inclusion of both FFPs-C and FFPs-B, with a similar chemical composition compared to traditional diets. Neither the FFPs-C nor FFPs-B diets affected the abundance and biodiversity indexes of the microbial community. Only a few taxa, normally attributed to a healthy gut, increased with FFPs-C and FFPs-B compared to the CTR. The experimental diets had no impact on the production of the VFAs in the faeces. Lastly, the inclusion at 30% (w/w) of both categories of FFP diets slightly affected the faecal microbiota. FFPs could thus be used as a promising alternative to traditional ingredients in pig diets; however, additional analyses are needed to further investigate the presence of potentially pathogenic bacteria. The effects of such ingredients on other markers of gut health, and on product quality when used in the fattening period also need to be investigated.     

Predicting nitrogen mineralization from organic amendments: beyond C/N ratio by 13C-CPMAS NMR approach

Plant and Soil - The processes of nitrogen (N) mineralization from organic amendments (OA) is important to provide mineral forms (NH4+ and NO3?) of N for plants. Assessment of N...     

Traits-based approaches support the conservation relevance of landscape genetics

Calls for evaluating general principles in landscape genetics reflect a broader recognition that multispecies inference is a promising strategy for supporting conservation actions across wide-ranging taxonomies and geographies. Formal evaluation of frameworks for multispecies inference is critical to identify opportunities for generalization and to avoid misguided extrapolation that results in ineffective conservation and management efforts. Traits-based approaches are now widely recognized as useful in addressing knowledge gaps where species-specific data may not be available or feasible to obtain. Here we present a case for the application of traits-based approaches in landscape genetics to improve conservation application. We discuss the fundamental theoretical framework and growing empirical evidence supporting the utility of traits-based approaches in landscape genetics, and we highlight an example of the implementation of traits to predict landscape genetic relationships for a range of aquatic taxa native to the southwestern United States. Finally, we discuss opportunities, challenges, and future directions of using traits to characterize landscape genetic relationships. Ultimately, traits-based approaches can help address growing calls for the development and testing of general principles in landscape genetics in order to improve application to conservation challenges.     

Identification of amdX, a new Cys-2–His-2 (C2H2) zinc-finger gene involved in the regulation of the amdS gene of Aspergillus nidulans

The acetamidase-encoding amdS gene of Aspergillus nidulans has been shown to be controlled by multiple regulatory genes. A new gene, amdX , involved in amdS regulation was identified during the characterization of a translocation affecting amdS control. The amdX gene is predicted to encode a 1150-amino-acid polypeptide which contains two Cys-2–His-2 (C2H2) zinc finger DNA-binding motifs. Insertional inactivation of amdX and the phenotypes of transformants containing multiple copies of the amdX gene show that it is an activator of amdS expression. A fusion protein containing the AmdX zinc fingers was found to bind to sequences in the 5' region of amdS which overlap binding sites for the CreA and AmdA regulatory proteins. Evidence is presented for AmdX acting at these sites in vivo .     

Isolation and characterization of granules of the toad bladder

Summary The electron-dense granules that lie just below the apical plasma membrane of granular epithelial cells of toad urinary bladder contribute glycoproteins to that apical membrane. Also, exocytosis of granules (and tubules) elicited by antidiuretic hormone potentially doubles that apical surface, during the same period the transport changes characteristic of the hormonal response occur.Granules separated from other membrane systems of the cells provide the material to assess the importance of the granules as glycocalyx precursors and in hormone action. We used isosmotic media to effect preliminary separations by differential centrifugation. Then granules were isolated by centrifugation on self-forming gradients of Percoll of decreasing hypertonicity.We find qualitative and quantitative changes in protein composition and enzymic activities in the isolated fractions. The primary criterion for granule purification was electron microscopic morphology. In addition, polypeptide species found in the granule fraction are limited in number and quantity. The granules are enzymically and morphologically not lysosomal in nature. Granules may provide the glycoproteins of the apical glycocalyx but they differ from the isolated plasma membrane fraction enzymically, in protein composition and in proportion of esterified cholesterol.We conclude that the granules are not average plasma membrane precursors. Their role in the membrane properties of the toad urinary bladder may now be evaluated by characterizing permeability and other properties of the isolated organelles.     

Decomposition and nutrient dynamics in mixed litter of Mediterranean species

In the last decade a great research effort addressed the effects of litter diversity on ecosystem functions, reporting both synergistic and antagonistic effects for decomposition dynamics. Four coexisting Mediterranean species, representing a range of litter quality, were used to arrange litter mixtures at three diversity levels for a litterbag decomposition experiment. Species identity appeared as the major determinant for litter mass loss (Coronilla emerus～Hedera helix>Festuca drymeia>Quercus ilex) and nutrient release, with rates for all leaf litter types following the sequence K>N>Mg≥Ca>>Fe. Additive diversity effects were prevalent pooling together all data but also for nutrients separately. Antagonistic interactions were more common than synergistic in the cases of mass loss, N and Ca contents, but not for K, Mg and Fe dynamics. The number of species in the litterbag significantly affected the outcome of non-additive interactions, which were mostly antagonistic for two-species mixtures, and synergistic for the combined 4 species. Litter quality appears to be the most important factor affecting mass loss and nutrient dynamics, while litter diversity, influencing the rates of these processes, plays an important role in reducing their variability, thus suggesting a greater stability of ecosystems properties in presence of mixed litter.