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The incidence of male fertility disorders has increased greatly due to various genetic and lifestyle factors. Recently, it has been hypothesized that vitamin D may be involved with idiopathic infertility. The goal of the study was to determine the effect and relationship between blood vitamin D metabolites, intracellular sperm vitamin D levels, and gene expression of 1‐α‐hydroxylase and VDR, with regard to semen quality. Seventy volunteers aged 25–45 were involved in the study. According to spermogram analysis, participants were stratified into normozoospermic control group, non‐normozoospermic target group, and oligoasthenoteratozoospermic group. Vitamin D metabolites (total 25‐hydroxycholecalciferol, 1,25‐dihydroxycholecalciferol) in blood and spermatozoa were determined by ELISA. Free and bioavailable 25‐hydroxycholecalciferol were calculated using the Vermeulen equation. mRNA expression of VDR and 1‐α hydroxylase was evaluated by qPCR. Free and bioavailable 25‐hydroxycholecalciferol were significantly higher in the control group compared to the target group and compared to the oligoasthenoteratozoospermic group. Intracellular sperm 1,25‐dihydroxycholecalciferol was higher in the control group compared to the target group. The mRNA levels of 1‐ α‐hydroxylase were significantly higher in the control samples, while VDR expression was significantly higher in the target group. Significant positive correlations were established between free and bioavailable 25‐hydroxycholecalciferol with sperm motility and morphology. Vitamin D metabolites in blood and intracellular sperm 1,25‐dihydroxycholecalciferol seem to exert beneficial effects on sperm motility and morphology. Regarding sperm quality, these effects are more pronounced in the free and bioavailable 25OHD compared to the total 25OHD in blood. Higher expression of 1‐α‐hydroxylase likely leads to higher intracellular levels of 1,25‐dihydroxycholecalciferol, which could contribute to sperm motility and morphology. Higher VDR expression may be a compensatory mechanism related to lower intracellular sperm 1,25‐dihydroxycholecalciferol. [ABSTRACT FROM AUTHOR]

Release of neurotransmitter is executed by complex multiprotein machinery, which is assembled around the presynaptic cytomatrix at the active zone. One well-established function of this proteinaceous scaffold is the spatial organization of synaptic vesicle cluster, the protein complexes that execute membrane fusion and compensatory endocytosis, and the transmembrane molecules important for alignment of pre- and postsynaptic structures. The presynaptic cytomatrix proteins function also in processes other than the formation of a static frame for assembly of the release apparatus and synaptic vesicle cycling. They actively contribute to the regulation of multiple steps in this process and are themselves an important subject of regulation during neuronal plasticity. We are only beginning to understand the mechanisms and signalling pathways controlling these regulations. They are mainly dependent on posttranslational modifications, including phosphorylation and small-molecules conjugation, such as ubiquitination. Ubiquitination of presynaptic proteins might lead to their degradation by proteasomes, but evidence is growing that this modification also affects their function independently of their degradation. Signalling from presynapse to nucleus, which works on a much slower time scale and more globally, emerged as an important mechanism for persistent usage-dependent and homeostatic neuronal plasticity. Recently, two new functions for the largest presynaptic scaffolding proteins bassoon and piccolo emerged. They were implied (1) in the regulation of specific protein ubiquitination and proteasome-mediated proteolysis that potentially contributes to short-term plasticity at the presynapse and (2) in the coupling of activity-induced molecular rearrangements at the presynapse with reprogramming of expression of neuronal activity-regulated genes. [ABSTRACT FROM AUTHOR]

Persistent experience-driven adaptation of brain function is associated with alterations in gene expression patterns, resulting in structural and functional neuronal remodeling. How synaptic activity-in particular presynaptic performance-is coupled to gene expression in nucleus remains incompletely understood. Here, we report on a role of Ct BP1, a transcriptional co-repressor enriched in presynapses and nuclei, in the activity-driven reconfiguration of gene expression in neurons. We demonstrate that presynaptic and nuclear pools of Ct BP1 are interconnected and that both synaptic retention and shuttling of Ct BP1 between cytoplasm and nucleus are co-regulated by neuronal activity. Finally, we show that Ct BP1 is targeted and/or anchored to presynapses by direct interaction with the active zone scaffolding proteins Bassoon and Piccolo. This association is regulated by neuronal activity via modulation of cellular NAD/ NADH levels and restrains the size of the Ct BP1 pool available for nuclear import, thus contributing to the control of activity-dependent gene expression. Our combined results reveal a mechanism for coupling activity-induced molecular rearrangements in the presynapse with reconfiguration of neuronal gene expression. [ABSTRACT FROM AUTHOR]

In the present work, we established a rapid, cost-effective and high-throughput method for genotyping using a multiplexed microsphere-based suspension array platform - Luminex × MAP™, which enabled us to analyse two SNPs in the promoter of IL-6 gene, determining haplotypes associated with different levels of expression. Using this system, IL-6 diversity in four different ethnic groups - East Asians, Caucasians, Hispanic and African Americans - was assessed. Results showed a significant variability in terms of allele, genotype and haplotype distribution. Considering the important immunoregulatory role of this cytokine and as a clinically relevant marker, this genotyping approach will provide a powerful tool for disease association or transplant outcome studies. [ABSTRACT FROM AUTHOR]

Here we report the first metatranscriptomic analysis of gene expression and regulation of ‘ Candidatus Accumulibacter’-enriched lab-scale sludge during enhanced biological phosphorus removal (EBPR). Medium density oligonucleotide microarrays were generated with probes targeting most predicted genes hypothesized to be important for the EBPR phenotype. RNA samples were collected at the early stage of anaerobic and aerobic phases (15 min after acetate addition and switching to aeration respectively). We detected the expression of a number of genes involved in the carbon and phosphate metabolisms, as proposed by EBPR models (e.g. polyhydroxyalkanoate synthesis, a split TCA cycle through methylmalonyl-CoA pathway, and polyphosphate formation), as well as novel genes discovered through metagenomic analysis. The comparison between the early stage anaerobic and aerobic gene expression profiles showed that expression levels of most genes were not significantly different between the two stages. The majority of upregulated genes in the aerobic sample are predicted to encode functions such as transcription, translation and protein translocation, reflecting the rapid growth phase of Accumulibacter shortly after being switched to aerobic conditions. Components of the TCA cycle and machinery involved in ATP synthesis were also upregulated during the early aerobic phase. These findings support the predictions of EBPR metabolic models that the oxidation of intracellularly stored carbon polymers through the TCA cycle provides ATP for cell growth when oxygen becomes available. Nitrous oxide reductase was among the very few Accumulibacter genes upregulated in the anaerobic sample, suggesting that its expression is likely induced by the deprivation of oxygen. [ABSTRACT FROM AUTHOR]

Vetiver is the only grass cultivated worldwide for the root essential oil, which is a mixture of sesquiterpene alcohols and hydrocarbons, used extensively in perfumery and cosmetics. Light and transmission electron microscopy demonstrated the presence of bacteria in the cortical parenchymatous essential oil-producing cells and in the lysigen lacunae in close association with the essential oil. This finding and the evidence that axenic Vetiver produces in vitro only trace amounts of oil with a strikingly different composition compared with the oils from in vivo Vetiver plants stimulated the hypothesis of an involvement of these bacteria in the oil metabolism. We used culture-based and culture-independent approaches to analyse the microbial community of the Vetiver root. Results demonstrate a broad phylogenetic spectrum of bacteria, including α-, β- and γ- Proteobacteria, high-G+C-content Gram-positive bacteria, and microbes belonging to the Fibrobacteres/ Acidobacteria group. We isolated root-associated bacteria and showed that most of them are able to grow by using oil sesquiterpenes as a carbon source and to metabolize them releasing into the medium a large number of compounds typically found in commercial Vetiver oils. Several bacteria were also able to induce gene expression of a Vetiver sesquiterpene synthase. These results support the intriguing hypothesis that bacteria may have a role in essential oil biosynthesis opening the possibility to use them to manoeuvre the Vetiver oil molecular structure. [ABSTRACT FROM AUTHOR]

Estrogen plays an important role during midbrain development. This is indicated by the presence of nuclear estrogen receptors and the transient expression of the estrogen-forming enzyme aromatase. A number of recent studies have shown that estrogen promotes the differentiation and survival, as well as physiological performance, of midbrain dopaminergic cells. In addition, we have reported that both ways of cellular estrogen signaling (classical and nonclassical) as well as interactions with nonneuronal target cells are involved in the transmission of intra- and intercellular estrogen effects in this brain region. This study provides additional evidence that (i) estrogen is capable of regulating gene expression in cultured embryonic neurons and astrocytes differently and (ii) both signaling mechanisms, i.e., classically through nuclear receptors and nonclassically through the stimulation of membrane-estrogen receptors, which are coupled to distinct intracellular signal transduction cascades, contribute diversely to gene regulation. These data reveal a high degree of complexity of estrogen action at the genomic level in the developing brain. Further studies are warranted to unravel the exact contribution of the differently regulated genes for developmental estrogen action. [ABSTRACT FROM AUTHOR]

We present evidence showing that rpoS (katF) is a regulator of katG gene transcription In an oxyR-Independent manner. Mutation of the rpoS gene in several different Escherichia coli strains caused a significant reduction in catalase HPI activity. In rpoS-ΔoxyR double mutants, the level of HPI was considerably lower compared to the ΔoxyR parent strain, and was restored when transformed with an rpoS+ plasmid. Overproduction of HPI in oxyR- suppressor strains was greatly diminished after inactivation of the rpoS gene and was accompanied by a substantial increase in sensitivity to menadione. Beta-galactostdase expression from a katG::lacZ promoter was lower in rpoS strains compared to rpoS+ isogenic parents. Several ΔoxyR strains had detectable levels of katG transcription that was significantiy diminished after rpoS gene Inactivation. [ABSTRACT FROM AUTHOR]