855 research outputs found
Genome-Wide Location Analysis Reveals Distinct Transcriptional Circuitry by Paralogous Regulators Foxa1 and Foxa2
Gene duplication is a powerful driver of evolution. Newly duplicated genes acquire new roles that are relevant to fitness, or they will be lost over time. A potential path to functional relevance is mutation of the coding sequence leading to the acquisition of novel biochemical properties, as analyzed here for the highly homologous paralogs Foxa1 and Foxa2 transcriptional regulators. We determine by genome-wide location analysis (ChIP-Seq) that, although Foxa1 and Foxa2 share a large fraction of binding sites in the liver, each protein also occupies distinct regulatory elements in vivo. Foxa1-only sites are enriched for p53 binding sites and are frequently found near genes important to cell cycle regulation, while Foxa2-restricted sites show only a limited match to the forkhead consensus and are found in genes involved in steroid and lipid metabolism. Thus, Foxa1 and Foxa2, while redundant during development, have evolved divergent roles in the adult liver, ensuring the maintenance of both genes during evolution.Institute for Diabetes, Obesity and Metabolism. Diabetes Research Center (Functional Genomics Core P30-DK19525
MALDI-TOF MS for the identification of cultivable organic-degrading bacteria in contaminated groundwater near unconventional natural gas extraction sites
Groundwater quality and quantity is of extreme importance as it is a source of drinking water in the United States. One major concern has emerged due to the possible contamination of groundwater from unconventional oil and natural gas extraction activities. Recent studies have been performed to understand if these activities are causing groundwater contamination, particularly with respect to exogenous hydrocarbons and volatile organic compounds. The impact of contaminants on microbial ecology is an area to be explored as alternatives for water treatment are necessary. In this work, we identified cultivable organic-degrading bacteria in groundwater in close proximity to unconventional natural gas extraction. Pseudomonas stutzeri and Acinetobacter haemolyticus were identified using matrix-assisted laser desorption/ionization-time-of-flight-mass spectrometry (MALDI-TOF MS), which proved to be a simple, fast, and reliable method. Additionally, the potential use of the identified bacteria in water and/or wastewater bioremediation was studied by determining the ability of these microorganisms to degrade toluene and chloroform. In fact, these bacteria can be potentially applied for in situ bioremediation of contaminated water and wastewater treatment, as they were able to degrade both compounds.info:eu-repo/semantics/publishedVersio
The endogenous caspase-8 inhibitor c-FLIPL regulates ER morphology and crosstalk with mitochondria
Components of the death receptors-mediated pathways like caspase-8 have been identified in complexes at intracellular membranes to spatially restrict the processing of local targets. In this study, we report that the long isoform of the cellular FLICE-inhibitory protein (c-FLIPL), a well- known inhibitor of the extrinsic cell death initiator caspase-8, localizes at the endoplasmic reticulum (ER) and mitochondria-associated membranes (MAMs). ER morphology was disrupted and ER Ca2+-release as well as ER-mitochondria tethering were decreased in c-FLIP-/- mouse embryonic fibroblasts (MEFs). Mechanistically, c-FLIP ablation resulted in enhanced basal caspase-8 activation and in caspase-mediated processing of the ER-shaping protein reticulon-4 (RTN4) that was corrected by re-introduction of c-FLIPL and caspase inhibition, resulting in the recovery of a normal ER morphology and ER-mitochondria juxtaposition. Thus, the caspase-8 inhibitor c-FLIPL emerges as a component of the MAMs signaling platforms, where caspases appear to regulate ER morphology and ER-mitochondria crosstalk by impinging on ER-shaping proteins like the RTN4
Marketing, the past and corporate heritage
Argues for a more expansive conceptualisation of the pastâs relevance in, and for, marketing. Such a differentiated approach to the past is pregnant with possibilities in terms of advancing scholarship apropos temporal agency in marketing along with consumption practices. Symptomatic of this perspective is the increased mindfulness of the rich palate of past-related concepts. Significantly, the corporate heritage notion - because of its omni-temporal nature - represents a distinct and meaningful vector on the past by coalescing the past, present and future into a new type of temporality. As such, the authors reason this expansive conceptualisation of âthe past-in-marketingâ is both timely and efficacious. Whilst sensitive of the importance of the historical method in marketing and the history of marketing scholarship and practice per se. This broader marketing approach to and of the past highlights the ideational and material manifestations of the past-in-the-present and an envisaged past-in-the future
Razvoj i biofarmaceutsko vrednovanje pripravka za poveÄano oslobaÄanje tramadol hidroklorida na principu osmotske tehnologije
Extended release formulation of tramadol hydrochloride (TRH) based on osmotic technology was developed and evaluated. Target release profile was selected and different variables were optimized to achieve the same. Formulation variables like level of swellable polymer, plasticizer and the coat thickness of semipermeable membrane (SPM) were found to markedly affect the drug release. TRH release was directly proportional to the levels of plasticizer but inversely proportional to the levels of swellable polymer and coat thickness of SPM. Drug release from developed formulations was independent of pH and agitation intensity but dependent on osmotic pressure of the release media. In vivo study was also performed on six healthy human volunteers and various pharmacokinetic parameters (cmax, tmax, AUC0-24, MRT) and relative bioavailability were calculated. The in vitro and in vivo results were compared with performance of two commercial tablets of TRH. The developed formulation provided more prolonged and controlled TRH release as compared to marketed formulation. In vitro-in vivo correlation (IVIVC) was analyzed according to Wagner-Nelson method. The optimized formulation (batch IVB) exhibited good IVIV correlation (R = 0.9750). The manufacturing procedure was found to be reproducible and formulations were stable during 6 months of accelerated stability testing.U radu je opisana priprava i evaluacija pripravaka tramadol hidroklorida (TRH) na principu osmotske tehnologije. Da bi se postigao ĆŸeljeni profil oslobaÄanja mijenjane su razliÄite varijable. Pokazalo se da najveÄi utjacaj na oslobaÄanje ljekovite tvari imaju udjeli polimera koji bubri, plastifikatora i debljina ovojnice polupropusne membrane (SPM). TRH oslobaÄanje bilo je proporcionalno udjelu plastifikatora, a obrnuto proporcionalno udjelu polimera i vrijednosti SPM. OslobaÄanje ljekovite tvari bilo je neovisno o pH i intenzitetu mijeĆĄanja, a ovisno o osmotskom talku medija. U in vivo studiji provedenoj na ĆĄest zdravih volontera odreÄeni su farmakokinetiÄki parametri (cmax, tmax, AUC0-24, MRT) i izraÄunata relativna bioraspoloĆŸivost. Rezultati dobiveni u pokusima in vitro i in vivo usporeÄeni su s dvije vrste komercijalno dostupnih tableta TRH: oslobaÄanje ljekovite tvari iz pripravka razvijenog u ovom radu bilo je dulje i viĆĄe kontrolirano. In vitro-in vivo korelacija (IVIVC) je analizirana prema Wagner-Nelsonovoj metodi. Optimizirani pripravak (IVB) pokazao je dobru IVIV korelaciju (R = 0,9750). Proizvodni proces je bio reproducibilan i pripravci su bili stabilni tijekom 6 mjeseci u uvjetima ubrzanog starenja
Mitochondrial genome sequence analysis: A custom bioinformatics pipeline substantially improves Affymetrix MitoChip v2.0 call rate and accuracy
BACKGROUND: Mitochondrial genome sequence analysis is critical to the diagnostic evaluation of mitochondrial disease. Existing methodologies differ widely in throughput, complexity, cost efficiency, and sensitivity of heteroplasmy detection. Affymetrix MitoChip v2.0, which uses a sequencing-by-genotyping technology, allows potentially accurate and high-throughput sequencing of the entire human mitochondrial genome to be completed in a cost-effective fashion. However, the relatively low call rate achieved using existing software tools has limited the wide adoption of this platform for either clinical or research applications. Here, we report the design and development of a custom bioinformatics software pipeline that achieves a much improved call rate and accuracy for the Affymetrix MitoChip v2.0 platform. We used this custom pipeline to analyze MitoChip v2.0 data from 24 DNA samples representing a broad range of tissue types (18 whole blood, 3 skeletal muscle, 3 cell lines), mutations (a 5.8 kilobase pair deletion and 6 known heteroplasmic mutations), and haplogroup origins. All results were compared to those obtained by at least one other mitochondrial DNA sequence analysis method, including Sanger sequencing, denaturing HPLC-based heteroduplex analysis, and/or the Illumina Genome Analyzer II next generation sequencing platform.
RESULTS: An average call rate of 99.75% was achieved across all samples with our custom pipeline. Comparison of calls for 15 samples characterized previously by Sanger sequencing revealed a total of 29 discordant calls, which translates to an estimated 0.012% for the base call error rate. We successfully identified 4 known heteroplasmic mutations and 24 other potential heteroplasmic mutations across 20 samples that passed quality control.
CONCLUSIONS: Affymetrix MitoChip v2.0 analysis using our optimized MitoChip Filtering Protocol (MFP) bioinformatics pipeline now offers the high sensitivity and accuracy needed for reliable, high-throughput and cost-efficient whole mitochondrial genome sequencing. This approach provides a viable alternative of potential utility for both clinical diagnostic and research applications to traditional Sanger and other emerging sequencing technologies for whole mitochondrial genome analysis
Caspase-8 binding to cardiolipin in giant unilamellar vesicles provides a functional docking platform for bid
Caspase-8 is involved in death receptor-mediated apoptosis in type II cells, the proapoptotic programme of which is triggered by truncated Bid. Indeed, caspase-8 and Bid are the known intermediates of this signalling pathway. Cardiolipin has been shown to provide an anchor and an essential activating platform for caspase-8 at the mitochondrial membrane surface. Destabilisation of this platform alters receptor-mediated apoptosis in diseases such as Barth Syndrome, which is characterised by the presence of immature cardiolipin which does not allow caspase-8 binding. We used a simplified in vitro system that mimics contact sites and/or cardiolipin-enriched microdomains at the outer mitochondrial surface in which the platform consisting of caspase-8, Bid and cardiolipin was reconstituted in giant unilamellar vesicles. We analysed these vesicles by flow cytometry and confirm previous results that demonstrate the requirement for intact mature cardiolipin for caspase-8 activation and Bid binding and cleavage. We also used confocal microscopy to visualise the rupture of the vesicles and their revesiculation at smaller sizes due to alteration of the curvature following caspase-8 and Bid binding. Biophysical approaches, including Laurdan fluorescence and rupture/tension measurements, were used to determine the ability of these three components (cardiolipin, caspase-8 and Bid) to fulfil the minimal requirements for the formation and function of the platform at the mitochondrial membrane. Our results shed light on the active functional role of cardiolipin, bridging the gap between death receptors and mitochondria
The nuclear receptors of Biomphalaria glabrata and Lottia gigantea: Implications for developing new model organisms
© 2015 Kaur et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are creditedNuclear receptors (NRs) are transcription regulators involved in an array of diverse physiological functions including key roles in endocrine and metabolic function. The aim of this study was to identify nuclear receptors in the fully sequenced genome of the gastropod snail, Biomphalaria glabrata, intermediate host for Schistosoma mansoni and compare these to known vertebrate NRs, with a view to assessing the snail's potential as a invertebrate model organism for endocrine function, both as a prospective new test organism and to elucidate the fundamental genetic and mechanistic causes of disease. For comparative purposes, the genome of a second gastropod, the owl limpet, Lottia gigantea was also investigated for nuclear receptors. Thirty-nine and thirty-three putative NRs were identified from the B. glabrata and L. gigantea genomes respectively, based on the presence of a conserved DNA-binding domain and/or ligand-binding domain. Nuclear receptor transcript expression was confirmed and sequences were subjected to a comparative phylogenetic analysis, which demonstrated that these molluscs have representatives of all the major NR subfamilies (1-6). Many of the identified NRs are conserved between vertebrates and invertebrates, however differences exist, most notably, the absence of receptors of Group 3C, which includes some of the vertebrate endocrine hormone targets. The mollusc genomes also contain NR homologues that are present in insects and nematodes but not in vertebrates, such as Group 1J (HR48/DAF12/HR96). The identification of many shared receptors between humans and molluscs indicates the potential for molluscs as model organisms; however the absence of several steroid hormone receptors indicates snail endocrine systems are fundamentally different.The National Centre for the Replacement, Refinement and Reduction of Animals in Research, Grant Ref:G0900802 to CSJ, LRN, SJ & EJR [www.nc3rs.org.uk]
Direct estimation of the mutation rate at dinucleotide microsatellite loci in Arabidopsis thaliana (Brassicaceae)
This is the author's accepted manuscript, made available with the permission of the publisher.This research was supported by NIH grant GM073990 and NSF grant DEB-0543052 to J. K. Kelly, NSF grants DEB-9629457 and DEB-9981891 to R. G. Shaw, and NSF DEB-0108242 to M. Orive. M. E. Mort acknowledges DEB-0344883
- âŠ