Higher-Order Looping and Nuclear Organization of Tcra Facilitate Targeted RAG Cleavage and Regulated Rearrangement in Recombination Centers

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Highlights? RAG-dependent monoallelic loop formation is linked to monoallelic RAG cleavage ? RAG enrichment, cleavage, and higher-order loop formation occur at the 3′ end of Tcra ? Looping out is a determinant of directed RAG targeting ? ATM-mediated control of looping out is linked to the maintenance of genome stability     

Nicotinamide nucleotide transhydrogenase mRNA expression is related to human obesity

Objective:

A spontaneous deletion in the nicotinamide nucleotide transhydrogenase (Nnt) gene eliminating exons 7‐11 in C57BL/6J (B6J) mice is associated with reduced glucose‐stimulated insulin secretion in vitro, impaired glucose tolerance, higher epigonadal fat mass, and altered susceptibility to diet induced obesity of male B6J mice was proposed. A potential implication for NNT in human adipose tissue distribution has not been investigated so far.

Design and Methods:

Therefore, NNT mRNA expression in paired human samples of visceral (vis) and subcutaneous (sc) adipose tissue from 221 subjects with a wide range of body mass index (BMI), insulin sensitivity, and glucose tolerance was analyzed.

Results:

NNT mRNA expression is significantly higher in visceral fat of obese patients and correlates with body weight, BMI, % body fat, visceral and sc fat area, waist and hip circumference, and fasting plasma insulin (FPI). Multivariate linear regression analysis revealed visceral NNT expression as age and gender independent predictor of BMI, waist circumference, visceral fat area, and % body fat, but not FPI and 2 h OGTT glucose.

Conclusion:

In conclusion, a functional relevance of NNT in the development of human obesity and visceral fat distribution was suggested here.     

Heme Oxygenase-1 (HO-1) Expression in Prostate Cancer Cells Modulates the Oxidative Response in Bone Cells

Prostate cancer (PCa) is a leading cause of death among males. It is currently estimated that inflammatory responses are linked to 15-20% of all deaths from cancer worldwide. PCa is dominated by complications arising from metastasis to the bone where the tumor cells interact with the bone microenvironment impairing the balance between bone formation and degradation. However, the molecular nature of this interaction is not completely understood. Heme oxygenase-1 (HO-1) counteracts oxidative damage and inflammation. Previous studies from our laboratory showed that HO-1 is implicated in PCa, demonstrating that endogenous HO-1 inhibits bone derived-prostate cancer cells proliferation, invasion and migration and decreases tumor growth and angiogenesis in vivo. The aim of this work was to analyze the impact of HO-1 modulated PCa cells on osteoblasts proliferation in vitro and on bone remodeling in vivo. Using a co-culture system of PC3 cells with primary mice osteoblasts (PMOs), we demonstrated that HO-1 pharmacological induction (hemin treatment) abrogated the diminution of PMOs proliferation induced by PCa cells and decreased the expression of osteoclast-modulating factors in osteoblasts. No changes were detected in the expression of genes involved in osteoblasts differentiation. However, co-culture of hemin pre-treated PC3 cells (PC3 Hem) with PMOs provoked an oxidative status and activated FoxO signaling in osteoblasts. The percentage of active osteoblasts positive for HO-1 increased in calvarias explants co-cultured with PC3 Hem cells. Nuclear HO-1 expression was detected in tumors generated by in vivo bone injection of HO-1 stable transfected PC3 (PC3HO-1) cells in the femur of SCID mice. These results suggest that HO-1 has the potential to modify the bone microenvironment impacting on PCa bone metastasis.     

Experimental warming increases herbivory by leaf‐chewing insects in an alpine plant community

Climate warming is predicted to affect species and trophic interactions worldwide, and alpine ecosystems are expected to be especially sensitive to changes. In this study, we used two ongoing climate warming (open‐top chambers) experiments at Finse, southern Norway, to examine whether warming had an effect on herbivory by leaf‐chewing insects in an alpine Dryas heath community. We recorded feeding marks on the most common vascular plant species in warmed and control plots at two experimental sites at different elevations and carried out a brief inventory of insect herbivores. Experimental warming increased herbivory on Dryas octopetala and Bistorta vivipara. Dryas octopetala also experienced increased herbivory at the lower and warmer site, indicating an overall positive effect of warming, whereas B. vivipara experienced an increased herbivory at the colder and higher site indicating a mixed effect of warming. The Lepidoptera Zygaena exulans and Sympistis nigrita were the two most common leaf‐chewing insects in the Dryas heath. Based on the observed patterns of herbivory, the insects life cycles and feeding preferences, we argue that Z. exulans is the most important herbivore on B. vivipara, and S. nigrita the most important herbivore on D. octopetala. We conclude that if the degree of insect herbivory increases in a warmer world, as suggested by this study and others, complex interactions between plants, insects, and site‐specific conditions make it hard to predict overall effects on plant communities.     

Survey of <Emphasis Type="Italic">Alternaria</Emphasis> toxin contamination in food from the German market,using a rapid HPLC-MS/MS approach

A HPLC-MS/MS-based method for the quantification of nine mycotoxins produced by fungi of the genus Alternaria in various food matrices was developed. The method relies on a single-step extraction, followed by dilution of the raw extract and direct analysis. In combination with an analysis time per sample of 12 min, the sample preparation is cost-effective and easy to handle. The method covers alternariol (AOH), alternariol monomethyl ether (AME), tenuazonic acid (TeA), altenuene (ALT), iso-altenuene (isoALT), tentoxin (TEN), altertoxin-I (ATX-I), and the AAL toxins TA₁ and TA₂. Some Alternaria toxins which are either not commercially available or very expensive, namely AOH, AME, ALT, isoALT, and ATX-I, were isolated as reference compounds from fungal cultures. The method was extensively validated for tomato products, bakery products, sunflower seeds, fruit juices, and vegetable oils. AOH, AME, TeA, and TEN were found in quantifiable amounts and 92.1 % of all analyzed samples (n?=?96) showed low level contamination with one or more Alternaria toxins. Based on the obtained results, the average daily exposure to Alternaria toxins in Germany was calculated.     

How reticulated are species?

Many groups of closely related species have reticulate phylogenies. Recent genomic analyses are showing this in many insects and vertebrates, as well as in microbes and plants. In microbes, lateral gene transfer is the dominant process that spoils strictly tree‐like phylogenies, but in multicellular eukaryotes hybridization and introgression among related species is probably more important. Because many species, including the ancestors of ancient major lineages, seem to evolve rapidly in adaptive radiations, some sexual compatibility may exist among them. Introgression and reticulation can thereby affect all parts of the tree of life, not just the recent species at the tips. Our understanding of adaptive evolution, speciation, phylogenetics, and comparative biology must adapt to these mostly recent findings. Introgression has important practical implications as well, not least for the management of genetically modified organisms in pest and disease control.     

Bioluminescence‐based assays for assessing eco‐ and genotoxicity of airborne emissions

Ecotoxicological tests (or bioassays) are controlled, reproducible tests where ecological responses are determined quantitatively. Due to numerous difficulties arising when airborne emissions are sampled, relatively few ecotoxicological assays have been applied. Aerosol particles are generally collected on a filter, which limits the quantity of the sample, thus also limiting the range of available test organisms. Bacterial bioassays require low sample quantity, and make a good choice when eco‐ or genotoxicity of the sample are to be determined. Of bacterial assays, the bioluminescence inhibition test has been proven applicable for assessing toxicity of airborne contaminants. In this paper diverse test protocols and their modifications are reviewed. Copyright © 2016 John Wiley & Sons, Ltd.     

Community participation and ecological criteria for selecting species and restoring natural capital with native species in the Sahel

Combining community needs and preferences with dryland plant expertise in order to select suitable native species for large‐scale natural capital restoration is the approach that has been successful in the Sahel as part of Africa's Great Green Wall program. In order to increase plant diversity and restore degraded land, we investigated four cross‐border regions of Mali, Burkina Faso, and Niger, all located in dryland ecosystems of the Sahel. In 120 beneficiary village communities, with a total population of over 50,000 farmers, including 51% women, participatory diagnostic meetings were conducted, leading to the selection of 193 plant species, most of which were mainly used for food, medicine, fodder, and fuel. Of these, 170 were native and considered suitable for enriching and restoring those village lands. The most environmentally well‐adapted and economically relevant species were prioritized, quality seeds were collected, and nursery seedlings produced under technical supervision of villages. From 2013 to 2015, 55 woody and herbaceous species were planted to initiate restoration of 2,235 ha of degraded land. On average, 60% of seedlings survived and grew well in the field after three rainy seasons. Due to its multiple uses, including gum arabic production, Acacia senegal was preferred by local people in most cases, accounting for 30% of seedlings planted. Such promising results, in an effort to restore degraded land for and with the help of thousands of farmers, could not have been achieved without the combination of scientific plant expertise and efficient rural capacity development, underpinned by high levels of community engagement.     

The art of vector engineering: towards the construction of next-generation genetic tools

When recombinant DNA technology was developed more than 40 years ago, no one could have imagined the impact it would have on both society and the scientific community. In the field of genetic engineering, the most important tool developed was the plasmid vector. This technology has been continuously expanding and undergoing adaptations. Here, we provide a detailed view following the evolution of vectors built throughout the years destined to study microorganisms and their peculiarities, including those whose genomes can only be revealed through metagenomics. We remark how synthetic biology became a turning point in designing these genetic tools to create meaningful innovations. We have placed special focus on the tools for engineering bacteria and fungi (both yeast and filamentous fungi) and those available to construct metagenomic libraries. Based on this overview, future goals would include the development of modular vectors bearing standardized parts and orthogonally designed circuits, a task not fully addressed thus far. Finally, we present some challenges that should be overcome to enable the next generation of vector design and ways to address it.