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Lactation is an essential process for mammals. In sheep, the R96C mutation in suppressor of cytokine signaling 2 (SOCS2) protein is associated with greater milk production and increased mastitis sensitivity. To shed light on the involvement of R96C mutation in mammary gland development and lactation, we developed a mouse model carrying this mutation (SOCS2KI/KI). Mammary glands from virgin adult SOCS2KI/KI mice presented a branching defect and less epithelial tissue, which were not compensated for in later stages of mammary development. Mammary epithelial cell (MEC) subpopulations were modified, with mutated mice having three times as many basal cells, accompanied by a decrease in luminal cells. The SOCS2KI/KI mammary gland remained functional; however, MECs contained more lipid droplets versus fat globules, and milk lipid composition was modified. Moreover, the gene expression dynamic from virgin to pregnancy state resulted in the identification of about 3000 differentially expressed genes specific to SOCS2KI/KI or controlmice. Our results show that SOCS2 is important for mammary gland development and milk production. In the long term, this finding raises the possibility of ensuring adequate milk production without compromising animal health and welfare. [ABSTRACT FROM AUTHOR]

Background: Micropollutants in bodies of water represent many challenges. We addressed these challenges by the application of constructed wetlands, which represent advanced treatment technology for the removal of micropollutants from water. However, which mechanisms specifically contribute to the removal efficiency often remains unclear. Methods: Here, we focus on the removal of 27 micropollutants by bioremediation. For this, macrophytes Phragmites australis, Iris pseudacorus and Lythrum salicaria were taken from established wetlands, and a special experimental set-up was designed. In order to better understand the impact of the rhizosphere microbiome, we determined the microbial composition using 16S rRNA gene sequencing and investigated the role of identified genera in the micropollutant removal of micropollutants. Moreover, we studied the colonization of macrophyte roots by arbuscular mycorrhizal fungi, which are known for their symbiotic relationship with plants. This symbiosis could result in increased removal of present micropollutants. Results: We found Iris pseudacorus to be the most successful bioremediative system, as it removed 22 compounds, including persistent ones, with more than 80% efficiency. The most abundant genera that contributed to the removal of micropollutants were Pseudomonas, Flavobacterium, Variovorax, Methylotenera, Reyranella, Amaricoccus and Hydrogenophaga. Iris pseudacorus exhibited the highest colonization rate (56%). Conclusions: Our experiments demonstrate the positive impact of rhizosphere microorganisms on the removal of micropollutants. [ABSTRACT FROM AUTHOR]

Many studies have focused on the mechanisms of stem cell maintenance via their interaction with a particular niche or microenvironment in adult tissues, but how formation of a functional niche is initiated, including how stem cells within a niche are established, is less well understood. Adult Drosophila melanogaster ovary Germline Stem Cell (GSC) niches are comprised of somatic cells forming a stack called a Terminal Filament (TF) and associated Cap and Escort Cells (CCs and ECs, respectively), which are in direct contact with GSCs. In the adult ovary, the transcription factor Engrailed is specifically expressed in niche cells where it directly controls expression of the decapentaplegic (dpp) gene encoding a member of the Bone Morphogenetic Protein (BMP) family of secreted signaling molecules, which are key factors for GSC maintenance. In larval ovaries, in response to BMP signaling from newly formed niches, adjacent primordial germ cells become GSCs. The bric-à-brac paralogs (bab1 and bab2) encode BTB/POZ domain-containing transcription factors that are expressed in developing niches of larval ovaries. We show here that their functions are necessary specifically within precursor cells for TF formation during these stages. We also identify a new function for Bab1 and Bab2 within developing niches for GSC establishment in the larval ovary and for robust GSC maintenance in the adult. Moreover, we show that the presence of Bab proteins in niche cells is necessary for activation of transgenes reporting dpp expression as of larval stages in otherwise correctly specified Cap Cells, independently of Engrailed and its paralog Invected (En/Inv). Moreover, strong reduction of engrailed/invected expression during larval stages does not impair TF formation and only partially reduces GSC numbers. In the adult ovary, Bab proteins are also required for dpp reporter expression in CCs. Finally, when bab2 was overexpressed at this stage in somatic cells outside of the niche, there were no detectable levels of ectopic En/Inv, but ectopic expression of a dpp transgene was found in these cells and BMP signaling activation was induced in adjacent germ cells, which produced GSC-like tumors. Together, these results indicate that Bab transcription factors are positive regulators of BMP signaling in niche cells for establishment and homeostasis of GSCs in the Drosophila ovary. Author summary: A stem cell is able to divide and produce two daughter cells, one of which retains stem cell status, the second, in contrast, becoming specialized for functions in the corresponding organ. Harnessing the potential of stem cells therefore represents opportunities for cell therapy upon organ damage. Maintenance of stem cells requires their interaction with specific cellular microenvironments called niches. Very little is known about how stem cell microenvironments are established during development and in pathological settings such as during cancer metastasis. The Drosophila adult ovary is probably the best characterized niche-stem cell system. It has been shown that niche cells secrete signaling proteins of the Bone Morphogenetic Protein (BMP) family, which by binding to receptors present at the membrane of adjacent Germline Stem Cells (GSCs), instruct these cells to maintain stem cell status. The analysis of ovaries mutant for the two bric-à-brac (bab) genes, showed that they are necessary within precursor cells for correct formation of GSC niches and for activation of the BMP pathway leading to the establishment of the first GSCs in the developing ovary. We have also found that Bab proteins contribute to GSC maintenance in the adult along with other transcription factors, Engrailed/Invected. Importantly, overproduction of one of the Bab proteins leads to the production of GSC tumors in the adult ovary underlining a role for this protein in GSC homeostasis. [ABSTRACT FROM AUTHOR]

The Gram-negative beta-proteobacterium Zoogloea sp. LCSB751 (LMG 29444) was newly isolated from foaming activated sludge of a municipal wastewater treatment plant. Here, we describe its draft genome sequence and annotation together with a general physiological and genomic analysis, as the first sequenced representative of the Zoogloea genus. Moreover, Zoogloea sp. gene expression in its environment is described using metatranscriptomic data obtained from the same treatment plant. The presented genomic and transcriptomic information demonstrate a pronounced capacity of this genus to synthesize poly-ß-hydroxyalkanoate within wastewater. [ABSTRACT FROM AUTHOR]

Background: This is the third in a series of publications presenting formal method validation for biospecimen processing in the context of accreditation in laboratories and biobanks. We report here optimization of a stool processing protocol validated for fitness-for-purpose in terms of downstream DNA-based analyses. Methods: Stool collection was initially optimized in terms of sample input quantity and supernatant volume using canine stool. Three DNA extraction methods (PerkinElmer MSM I®, Norgen Biotek All-In-One®, MoBio PowerMag®) and six collection container types were evaluated with human stool in terms of DNA quantity and quality, DNA yield, and its reproducibility by spectrophotometry, spectrofluorometry, and quantitative PCR, DNA purity, SPUD assay, and 16S rRNA gene sequence-based taxonomic signatures. Results: The optimal MSM I protocol involves a 0.2 g stool sample and 1000 μL supernatant. The MSM I extraction was superior in terms of DNA quantity and quality when compared to the other two methods tested. Optimal results were obtained with plain Sarstedt tubes (without stabilizer, requiring immediate freezing and storage at −20°C or −80°C) and Genotek tubes (with stabilizer and RT storage) in terms of DNA yields (total, human, bacterial, and double-stranded) according to spectrophotometry and spectrofluorometry, with low yield variability and good DNA purity. No inhibitors were identified at 25 ng/μL. The protocol was reproducible in terms of DNA yield among different stool aliquots. Conclusions: We validated a stool collection method suitable for downstream DNA metagenomic analysis. DNA extraction with the MSM I method using Genotek tubes was considered optimal, with simple logistics in terms of collection and shipment and offers the possibility of automation. Laboratories and biobanks should ensure protocol conditions are systematically recorded in the scope of accreditation. [ABSTRACT FROM AUTHOR]

High-throughput sequencing of ribosomal RNA gene (rDNA) amplicons has opened up the door to large-scale comparative studies of microbial community structures. The short reads currently produced by massively parallel sequencing technologies make the choice of sequencing region crucial for accurate phylogenetic assignments. While for 16S rDNA, relevant regions have been well described, no truly systematic design of 18S rDNA primers aimed at resolving eukaryotic diversity has yet been reported. Here we used 31,862 18S rDNA sequences to design a set of broad-taxonomic range degenerate PCR primers. We simulated the phylogenetic information that each candidate primer pair would retrieve using paired- or single-end reads of various lengths, representing different sequencing technologies. Primer pairs targeting the V4 region performed best, allowing discrimination with paired-end reads as short as 150 bp (with 75% accuracy at genus level). The conditions for PCR amplification were optimised for one of these primer pairs and this was used to amplify 18S rDNA sequences from isolates as well as from a range of environmental samples which were then Illumina sequenced and analysed, revealing good concordance between expected and observed results. In summary, the reported primer sets will allow minimally biased assessment of eukaryotic diversity in different microbial ecosystems. [ABSTRACT FROM AUTHOR]