Kank Is an EB1 Interacting Protein that Localises to Muscle-Tendon Attachment Sites in Drosophila

Little is known about how microtubules are regulated in different cell types during development. EB1 plays a central role in the regulation of microtubule plus ends. It directly binds to microtubule plus ends and recruits proteins which regulate microtubule dynamics and behaviour. We report the identification of Kank, the sole Drosophila orthologue of human Kank proteins, as an EB1 interactor that predominantly localises to embryonic attachment sites between muscle and tendon cells. Human Kank1 was identified as a tumour suppressor and has documented roles in actin regulation and cell polarity in cultured mammalian cells. We found that Drosophila Kank binds EB1 directly and this interaction is essential for Kank localisation to microtubule plus ends in cultured cells. Kank protein is expressed throughout fly development and increases during embryogenesis. In late embryos, it accumulates to sites of attachment between muscle and epidermal cells. A kank deletion mutant was generated. We found that the mutant is viable and fertile without noticeable defects. Further analysis showed that Kank is dispensable for muscle function in larvae. This is in sharp contrast to C. elegans in which the Kank orthologue VAB-19 is required for development by stabilising attachment structures between muscle and epidermal cells

An Integrated Model of Multiple-Condition ChIP-Seq Data Reveals Predeterminants of Cdx2 Binding

Regulatory proteins can bind to different sets of genomic targets in various cell types or conditions. To reliably characterize such condition-specific regulatory binding we introduce MultiGPS, an integrated machine learning approach for the analysis of multiple related ChIP-seq experiments. MultiGPS is based on a generalized Expectation Maximization framework that shares information across multiple experiments for binding event discovery. We demonstrate that our framework enables the simultaneous modeling of sparse condition-specific binding changes, sequence dependence, and replicate-specific noise sources. MultiGPS encourages consistency in reported binding event locations across multiple-condition ChIP-seq datasets and provides accurate estimation of ChIP enrichment levels at each event. MultiGPS's multi-experiment modeling approach thus provides a reliable platform for detecting differential binding enrichment across experimental conditions. We demonstrate the advantages of MultiGPS with an analysis of Cdx2 binding in three distinct developmental contexts. By accurately characterizing condition-specific Cdx2 binding, MultiGPS enables novel insight into the mechanistic basis of Cdx2 site selectivity. Specifically, the condition-specific Cdx2 sites characterized by MultiGPS are highly associated with pre-existing genomic context, suggesting that such sites are pre-determined by cell-specific regulatory architecture. However, MultiGPS-defined condition-independent sites are not predicted by pre-existing regulatory signals, suggesting that Cdx2 can bind to a subset of locations regardless of genomic environment. A summary of this paper appears in the proceedings of the RECOMB 2014 conference, April 2–5.National Science Foundation (U.S.) (Graduate Research Fellowship under Grant 0645960)National Institutes of Health (U.S.) (grant P01 NS055923)Pennsylvania State University. Center for Eukaryotic Gene Regulatio

Aqueous Redox Flow Battery Suitable for High Temperature Applications Based on a Tailor‐Made Ferrocene Copolymer

Abstract Water‐soluble, and ferrocene‐containing methacrylamide copolymers with different comonomer ratios of the solubility‐promoting comonomer [2‐(methacryloyloxy)‐ethyl]‐trimethylammonium chloride (METAC) are synthesized in order to obtain a novel, temperature‐stable electrolyte for aqueous redox flow batteries. The electrochemical properties of one chosen polymer are studied in detail by cyclic voltammetry and rotating disc electrode (RDE) investigations. Additionally, the diffusion coefficient and the charge transfer rate are obtained from these measurements. The diffusion coefficient from RDE is compared to the value from synthetic boundary experiments at battery concentrations, using an analytical ultracentrifuge, yielding diffusion coefficients of a similar order of magnitude. The polymer is further tested in a redox flow battery setup. While performing charge and discharge experiments against the well‐established bis ‐(trimethylammoniumpropyl)‐viologen, the polymer reveals high columbic efficiencies of >99.8% and desirable apparent capacity retention, both at room temperature as well as at 60 °C. Further experiments are conducted to verify the stability of the active compounds under these conditions in both charge states. Lastly, the electrochemical behavior is linked to the characteristics of the polymers concerning absolute values of the molar mass and diffusion coefficients.A new ferrocene containing monomer is synthesized and its copolymerization with a water‐solubility promoting comonomer is investigated. The electrochemical and solution characteristics of a corresponding polymer are studied in detail. With a coulombic efficiency of >99.8% in an aqueous redox flow battery setup at 60 °C, a cheap, robust system for use at elevated temperatures is presented. imag

A viologen polymer and a compact ferrocene: Comparison of solution viscosities and their performance in a redox flow battery with a size exclusion membrane

In this work, the synthesis and characterization of a compact, ferrocene tetramer and a linear viologen polymer is reported. The latter material is a new, 4,4′‐bipyridine containing, organo‐soluble polymer. As aimed for solubility in nonpolar solvents, a 2‐ethylhexyl‐moiety to promote organosolubility and 4‐vinylbenzyl serving as a polymerizable group are introduced to a 4,4′‐bipyridine. The halide anions of the monomer cation are exchanged to bis(trifluoromethansulfon)imide, which further enhances organosolubility. The monomer is subsequently copolymerized with styrene by free radical polymerization. In addition, a four‐ferrocene‐containing compact structure, based on pentaerythritol, is synthesized via the straightforward radical thiol‐ene reaction. The polymer solutions are thoroughly characterized hydrodynamically. Subsequently, propylene carbonate‐based solutions of both materials are prepared to allow an assessment for future energy storage applications. This is done by testing battery characteristics in a custom‐made flow‐cell with a simple dialysis membrane for physical separation of the active materials. The capability of energy storage is verified by leaving the charged materials in solution in an open circuit for 24 h. Here, more than 99% of the stored charges can be recovered. Cycling the battery for 100 times reveals the remarkable stability of the materials of only 0.2% capacity loss per day in the battery setup

A mRNA landscape of bovine embryos after standard and MAPK-inhibited culture conditions: a comparative analysis.

BACKGROUND: Genes and signalling pathways involved in pluripotency have been studied extensively in mouse and human pre-implantation embryos and embryonic stem (ES) cells. The unsuccessful attempts to generate ES cell lines from other species including cattle suggests that other genes and pathways are involved in maintaining pluripotency in these species. To investigate which genes are involved in bovine pluripotency, expression profiles were generated from morula, blastocyst, trophectoderm and inner cell mass (ICM) samples using microarray analysis. As MAPK inhibition can increase the NANOG/GATA6 ratio in the inner cell mass, additionally blastocysts were cultured in the presence of a MAPK inhibitor and changes in gene expression in the inner cell mass were analysed. RESULTS: Between morula and blastocyst 3,774 genes were differentially expressed and the largest differences were found in blastocyst up-regulated genes. Gene ontology (GO) analysis shows lipid metabolic process as the term most enriched with genes expressed at higher levels in blastocysts. Genes with higher expression levels in morulae were enriched in the RNA processing GO term. Of the 497 differentially expressed genes comparing ICM and TE, the expression of NANOG, SOX2 and POU5F1 was increased in the ICM confirming their evolutionary preserved role in pluripotency. Several genes implicated to be involved in differentiation or fate determination were also expressed at higher levels in the ICM. Genes expressed at higher levels in the ICM were enriched in the RNA splicing and regulation of gene expression GO term. Although NANOG expression was elevated upon MAPK inhibition, SOX2 and POU5F1 expression showed little increase. Expression of other genes in the MAPK pathway including DUSP4 and SPRY4, or influenced by MAPK inhibition such as IFNT, was down-regulated. CONCLUSION: The data obtained from the microarray studies provide further insight in gene expression during bovine embryonic development. They show an expression profile in pluripotent cells that indicates a pluripotent, epiblast-like state. The inability to culture ICM cells as stem cells in the presence of an inhibitor of MAPK activity together with the reported data indicates that MAPK inhibition alone is not sufficient to maintain a pluripotent character in bovine cells

Chronic pain in primary care. German figures from 1991 and 2006

<p>Abstract</p> <p>Background</p> <p>Until now only limited research has been done on the prevalence of chronic pain in primary care. The aim of this investigation was to study the health care utilisation of patients suffering from pain. How many patients visit an outpatient clinic because of the symptom of pain? These data were compared with data from a similar study in 1991, to investigate whether improvements had been achieved.</p> <p>Methods</p> <p>A total of 1201 consecutive patients visiting outpatient clinics were surveyed in six practices in the western part of Germany on randomly selected days by means of questionnaires. Topics were the point prevalence of pain and the period prevalence of chronic pain, its characteristics and its impact on daily life, as well as data on previous therapies for pain. A retrospective comparison was made with the data from a similar study with same design surveying 900 patients that took place in five practices during 1991.</p> <p>Results</p> <p>In 2006, pain was the main reason for consulting a doctor in 42.5% of all patients (1991: 50.3%). Of all respondents, 62% suffered from pain on the particular day of the consultation, and 40% reported that they had been suffering from pain for more than six months (1991: 36.4%). As many as 88.3% of patients with chronic pain reported a negative impact on their daily life due to this pain (1991: 68%), and 88.1% reported impairment of their working life because of chronic pain (1991: 59.1%).</p> <p>Conclusion</p> <p>Pain, and chronic pain in particular, is a central problem in primary care. Over the last 15 years, the number of patients suffering from chronic pain has not decreased. In nearly half of all cases, pain is still the reason for health care utilisation in outpatient clinics. Pain represents a major primary health care problem with enormous impact on public health. Improvements can only be achieved by improving the quality of health care at the primary care level.</p

Notch signaling in mouse blastocyst development and hatching

Research Areas: Developmental BiologyBackground: Mammalian early embryo development requires a well-orchestrated interplay of cell signaling pathways. Notch is a major regulatory pathway involved in cell-fate determination in embryonic and adult scenarios. However, the role of Notch in embryonic pre-implantation development is controversial. In particular, Notch role on blastocyst development and hatching remains elusive, and a complete picture of the transcription and expression patterns of Notch components during this time-period is not available. Results: This study provided a comprehensive view on the dynamics of individual embryo gene transcription and protein expression patterns of Notch components (receptors Notch1–4; ligands Dll1 and Dll4, Jagged1–2; and effectors Hes1–2), and their relationship with transcription of gene markers of pluripotency and differentiation (Sox2, Oct4, Klf4, Cdx2) during mouse blastocyst development and hatching. Transcription of Notch1–2, Jagged1–2 and Hes1 was highly prevalent and dynamic along stages of development, whereas transcription of Notch3–4, Dll4 and Hes2 had a low prevalence among embryos. Transcription levels of Notch1, Notch2, Jagged2 and Hes1 correlated with each other and with those of pluripotency and differentiation genes. Gene transcription was associated to protein expression, except for Jagged2, where high transcription levels in all embryos were not translated into protein. Presence of Notch signaling activity was confirmed through nuclear NICD and Hes1 detection, and downregulation of Hes1 transcription following canonical signaling blockade with DAPT. In vitro embryo culture supplementation with Jagged1 had no effect on embryo developmental kinetics. In contrast, supplementation with Jagged2 abolished Jagged1 transcription, downregulated Cdx2 transcription and inhibited blastocyst hatching. Notch signaling blockade by DAPT downregulated transcription of Sox2, and retarded embryo hatching. Conclusion: Transcription of Notch genes showed a dynamic pattern along blastocyst development and hatching. Data confirmed Notch signaling activity, and lead to the suggestion that Notch canonical signaling may be operating through Notch1, Notch3, Jagged1 and Hes1. Embryo culture supplementation with Jagged1 and Jagged2 unveiled a possible regulatory effect between Jagged1, Cdx2 and blastocyst hatching. Overall, results indicate that a deregulation in Notch signaling, either by its over or under-activation, affects blastocyst development and hatching.info:eu-repo/semantics/publishedVersio

SNAI1 and SNAI2 Are Asymmetrically Expressed at the 2-Cell Stage and Become Segregated to the TE in the Mouse Blastocyst

SNAI1 and SNAI2 are transcription factors that initiate Epithelial-to-Mesenchymal cell transitions throughout development and in cancer metastasis. Here we show novel expression of SNAI1 and SNAI2 throughout mouse preimplantation development revealing asymmetrical localization of both SNAI1 and SNAI2 in individual blastomeres beginning at the 2-cell stage through to the 8-cell stage where SNAI1 and SNAI2 are then only detected in outer cells and not inner cells of the blastocyst. This study implicates SNAI1 and SNAI2 in the lineage segregation of the trophectoderm and inner cell mass, and provides new insight into these oncogenes

Wdr74 Is Required for Blastocyst Formation in the Mouse

Preimplantation is a dynamic developmental period during which a combination of maternal and zygotic factors program the early embryo resulting in lineage specification and implantation. A reverse genetic RNAi screen in mouse embryos identified the WD Repeat Domain 74 gene (Wdr74) as being required for these critical first steps of mammalian development. Knockdown of Wdr74 results in embryos that develop normally until the morula stage but fail to form blastocysts or properly specify the inner cell mass and trophectoderm. In Wdr74-deficient embryos, we find activated Trp53-dependent apoptosis as well as a global reduction of RNA polymerase I, II and III transcripts. In Wdr74-deficient embryos blocking Trp53 function rescues blastocyst formation and lineage differentiation. These results indicate that Wdr74 is required for RNA transcription, processing and/or stability during preimplantation development and is an essential gene in the mouse