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The heterogeneity underlying cancer organoid phenotypes is not yet well understood. Here, the authors develop an imaging analysis assay for high throughput phenotypic screening of colorectal organoids that allows to define specific morphological changes that occur following different drug treatments.

After 20 years of terahertz cross-correlation spectroscopy (THz-CCS), the performance of the systems has been improved to practical relevance by reaching a bandwidth of ~2 THz. For the development of high-performance THz-CCS systems, it is necessary to get a deeper knowledge of the signal generation from incoherent light sources. In this work, the bandwidth, dynamic range, and peak-to-peak amplitude of a THz-CCS systems using a superluminescent diode as light source and a programmable optical filter for spectral shaping was investigated to obtain a better understanding of the relationship between the optical spectrum and the generated terahertz spectrum. By a periodic structuring of the continuous optical spectrum, an enhancement of the peak dynamic range of more than 10 dB was achieved with a bandwidth of 1.6 THz. The experimental results are confirmed by numerical simulations.

Abstract DEHP is a plasticizer which has been used in plastic products of everyday use for decades. Studies in mice and murine cell culture models identified DEHP as an endocrine disruptor that may also act as an obesogen. As this is of high concern in respect of the worldwide obesity epidemic, our aim is the translation of these findings into a human model system. On the basis of DOHaD, we investigated the influence of an environmentally relevant dose of DEHP [50 µg/ml] on adipogenesis in the human cell culture model SGBS. Pre-adipocytes were exposed to DEHP and differentiated into mature adipocytes. At different stages of differentiation, markers of adipogenesis like GLUT4, FABP4, LPL and PPARs, and of signaling pathways like AMPK/ACC2, JAK/STAT and MAPK were analyzed. Functional markers like adipokine secretion and triglyceride content as well as ROS production were measured in mature adipocytes. We found significantly lower expression levels of adipogenic markers, a reduction in lipid accumulation, higher leptin- and reduced adiponectin levels in the supernatant of treated adipocytes. Moreover, ROS production was significantly elevated after DEHP-exposure. In conclusion, DEHP led to lower grade of adipogenic differentiation in human SGBS-adipocytes under the chosen conditions.

RNA functions through the dynamic formation of complexes with RNA-binding proteins (RBPs) in all clades of life. We determined the RBP repertoire of beating cardiomyocytic HL-1 cells by jointly employing two in vivo proteomic methods, mRNA interactome capture and RBDmap. Together, these yielded 1,148 RBPs, 391 of which are shared with all other available mammalian RBP repertoires, while 393 are thus far unique to cardiomyocytes. RBDmap further identified 568 regions of RNA contact within 368 RBPs. The cardiomyocyte mRNA interactome composition reflects their unique biology. Proteins with roles in cardiovascular physiology or disease, mitochondrial function, and intermediary metabolism are all highly represented. Notably, we identified 73 metabolic enzymes as RBPs. RNA-enzyme contacts frequently involve Rossmann fold domains with examples in evidence of both, mutual exclusivity of, or compatibility between RNA binding and enzymatic function. Our findings raise the prospect of previously hidden RNA-mediated regulatory interactions among cardiomyocyte gene expression, physiology, and metabolism.

Early development is controlled by maternally deposited mRNAs and the RNA-binding proteins (RBPs) that regulate them. Here the authors describe the identification of a large number of RBPs bound to polyadenylated RNAs in Drosophilaembryos before and after the maternal-to-zygotic transition, revealing changes in RBPs activity during development.

Objective: The food contaminants bisphenol A (BPA), diethylhexylphthalate (DEHP), and tributyltin (TBT) are potent endocrine-disrupting compounds (EDC) known to interfere with adipogenesis. EDC usually act in mixtures and not as single compounds. The aim of this study was to investigate the effects of a simultaneous exposure of BPA, DEHP, and TBT on mesenchymal stem cell differentiation into adipocytes. Methods: Multipotent murine mesenchymal stem cells (C3H10T1/2) were exposed to EDC mixtures in high concentrations, i.e. MIX-high (10 µmol/l BPA, 100 µmol/l DEHP, 100 nmol/l TBT), and in environmentally relevant concentrations, i.e. MIX-low (10 nmol/l BPA, 100 nmol/l DEHP, 1 nmol/l TBT). The exposure was performed either for the entire culture time (0-12 days) or at distinct stages of adipogenic differentiation. At day 12 of cell culture, the amount of adipocytes, triglyceride content (TG), and adipogenic marker gene expression were analyzed. Results: MIX-high increased the development of adipocytes and the expression of adipogenic marker genes independently of the exposure window. The total TG amount was not increased. The low-concentrated EDC mixture had no obvious impact on adipogenesis. Conclusion: In EDC mixtures, the adipogenic effect of TBT and DEHP predominates single effects of BPA. Mixture effects of EDC are not deducible from single compound experiments.

Gene–gene interactions shape complex phenotypes and modify the effects of mutations during development and disease. The effects of statistical gene–gene interactions on phenotypes have been used to assign genes to functional modules. However, directional, epistatic interactions, which reflect regulatory relationships between genes, have been challenging to map at large-scale. Here, we used combinatorial RNA interference and automated single-cell phenotyping to generate a large genetic interaction map for 21 phenotypic features of Drosophila cells. We devised a method that combines genetic interactions on multiple phenotypes to reveal directional relationships. This network reconstructed the sequence of protein activities in mitosis. Moreover, it revealed that the Ras pathway interacts with the SWI/SNF chromatin-remodelling complex, an interaction that we show is conserved in human cancer cells. Our study presents a powerful approach for reconstructing directional regulatory networks and provides a resource for the interpretation of functional consequences of genetic alterations.

During pregnancy an adequate amino acid supply is essential for embryo development and fetal growth. We have studied amino acid composition and branched chain amino acid (BCAA) metabolism at day 6 p.c. in diabetic rabbits and blastocysts. In the plasma of diabetic rabbits the concentrations of 12 amino acids were altered in comparison to the controls. Notably, the concentrations of the BCAA leucine, isoleucine and valine were approximately three-fold higher in diabetic rabbits than in the control. In the cavity fluid of blastocysts from diabetic rabbits BCAA concentrations were twice as high as those from controls, indicating a close link between maternal diabetes and embryonic BCAA metabolism. The expression of BCAA oxidizing enzymes and BCAA transporter was analysed in maternal tissues and in blastocysts. The RNA amounts of three oxidizing enzymes, i.e. branched chain aminotransferase 2 (Bcat2), branched chain ketoacid dehydrogenase (Bckdha) and dehydrolipoyl dehydrogenase (Dld), were markedly increased in maternal adipose tissue and decreased in liver and skeletal muscle of diabetic rabbits than in those of controls. Blastocysts of diabetic rabbits revealed a higher Bcat2 mRNA and protein abundance in comparison to control blastocysts. The expression of BCAA transporter LAT1 and LAT2 were unaltered in endometrium of diabetic and healthy rabbits, whereas LAT2 transcripts were increased in blastocysts of diabetic rabbits. In correlation to high embryonic BCAA levels the phosphorylation amount of the nutrient sensor mammalian target of rapamycin (mTOR) was enhanced in blastocysts caused by maternal diabetes. These results demonstrate a direct impact of maternal diabetes on BCAA concentrations and degradation in mammalian blastocysts with influence on embryonic mTOR signalling.

Di-(2-ethylhexyl)-phthalate (DEHP), an ubiquitous environmental contaminant, has been shown to cause adverse effects on glucose homeostasis and insulin sensitivity in epidemiological studies, but the underlying mechanisms are still unknown. We therefore tested the hypothesis that chronic DEHP exposure causes impaired insulin sensitivity, affects body weight, adipose tissue (AT) function and circulating metabolic parameters of obesity resistant 129S6 mice in vivo. An obesity-resistant mouse model was chosen to reduce a potential obesity bias of DEHP effects on metabolic parameters and AT function. The metabolic effects of 10-weeks exposure to DEHP were tested by insulin tolerance tests and quantitative assessment of 183 metabolites in mice. Furthermore, 3T3-L1 cells were cultured with DEHP for two days, differentiated into mature adipocytes in which the effects on insulin stimulated glucose and palmitate uptake, lipid content as well as on mRNA/protein expression of key adipocyte genes were investigated. We observed in female mice that DEHP treatment causes enhanced weight gain, fat mass, impaired insulin tolerance, changes in circulating adiponectin and adipose tissue Pparg, adiponectin and estrogen expression. Serum metabolomics indicated a general increase in phospholipid and carnitine concentrations. In vitro, DEHP treatment increases the proliferation rate and alters glucose uptake in adipocytes. Taken together, DEHP has significant effects on adipose tissue (AT) function and alters specific serum metabolites. Although, DEHP treatment led to significantly impaired insulin tolerance, it did not affect glucose tolerance, HOMA-IR, fasting glucose, insulin or triglyceride serum concentrations. This may suggest that DEHP treatment does not cause impaired glucose metabolism at the whole body level.

Wind and turbulence profiles measured over a period of one year by Doppler sodar and ultra sonic anemometers/thermometers at two sites in Germany with different roughness lengths and climates were analyzed. The profiles were stratified with respect to the surface Monin-Obukhov stability. The quality of various parameterizations for profiles is discussed by comparison with actually measured profiles. It turns out that actual state of the art sodar measurements are superior to all kinds of considered paramerizations at least for heights above 50 m. In addition, the mean diurnal cycle of wind and turbulence was evaluated as a function of height. It is shown that the atmospheric boundary layer - including the surface layer - is not in dynamic equilibrium with the surface fluxes. This may explain one of the major uncertainties of universal profiles which are generally postulated to exist in the surface layer over homogeneous terrain. Wind- und Turbulenzprofile wurden analysiert, die über einen Zeitraum von einem Jahr mit Doppler Sodar und Ultraschall-Anemometer-Thermometern an zwei Orten in Deutschland mit unterschiedlichen Rauhigkeitslängen und Klimaten gemessen wurden. Die Profile wurden nach der bodennahen Monin-Obukhov Stabilität sortiert. Die Qualität verschiedener Profil-Parameterisierungen wird anhand von Vergleichen mit gemessen Profilen diskutiert. Es ergibt sich, dass aktuelle, dem Stand der Technik entsprechende, Sodar Messungen allen betrachteten Parameterisierungen zumindest oberhalb 50m Messhöhe überlegen sind. Zusätzlich wurde der mittlere Tagesgang von Wind und Turbulenz ausgewertet. Es wird gezeigt, dass die atmosphärische Grenzschicht - einschließlich der Bodenschicht - nicht im dynamischen Gleichgewicht mit den Bodenflüssen steht. Dies könnte eine der größeren Unsicherheiten universeller Profile erklären, deren Existenz in der Bodenschicht über homogenem Gelände üblicherweise postuliert wird.

My introductory essay discusses some of transculturalism’s enduring conceptual challenges from the perspective of the history of German cultural and political theory. I am particularly interested in the discursive space between Immanuel Kant’s individualism and Johann Gottfried Herder’s and Moses Mendelssohn’s concepts of cultural identity. My hope is that such a discussion can enrich some of our current questions, such as: Have culture studies placed too much emphasis on difference, rather than on commonality? Can a renewed interest in the cosmopolitan individual surpass the privileged position of academic or upper-class internationalism? Can concepts of transculturality avoid the pitfalls of homogenizing politics or overstretched individualism? After mentioning a few challenges to current conceptions of transculturalism that may arise in the wake of recent developments in the natural sciences, I end my remarks with a brief example of a possible intersection of literary studies and science. The essay engages three topics: (a) the question of culture; (b) transcultural participation; and (c) transcultural empathy and the sciences.

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