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Sample records for chemoreceptor subfamilies differentially

  1. Identification of a chemoreceptor for tricarboxylic acid cycle intermediates: differential chemotactic response towards receptor ligands.

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    Lacal, Jesús; Alfonso, Carlos; Liu, Xianxian; Parales, Rebecca E; Morel, Bertrand; Conejero-Lara, Francisco; Rivas, Germán; Duque, Estrella; Ramos, Juan L; Krell, Tino

    2010-07-23

    We report the identification of McpS as the specific chemoreceptor for 6 tricarboxylic acid (TCA) cycle intermediates and butyrate in Pseudomonas putida. The analysis of the bacterial mutant deficient in mcpS and complementation assays demonstrate that McpS is the only chemoreceptor of TCA cycle intermediates in the strain under study. TCA cycle intermediates are abundantly present in root exudates, and taxis toward these compounds is proposed to facilitate the access to carbon sources. McpS has an unusually large ligand-binding domain (LBD) that is un-annotated in InterPro and is predicted to contain 6 helices. The ligand profile of McpS was determined by isothermal titration calorimetry of purified recombinant LBD (McpS-LBD). McpS recognizes TCA cycle intermediates but does not bind very close structural homologues and derivatives like maleate, aspartate, or tricarballylate. This implies that functional similarity of ligands, such as being part of the same pathway, and not structural similarity is the primary element, which has driven the evolution of receptor specificity. The magnitude of chemotactic responses toward these 7 chemoattractants, as determined by qualitative and quantitative chemotaxis assays, differed largely. Ligands that cause a strong chemotactic response (malate, succinate, and fumarate) were found by differential scanning calorimetry to increase significantly the midpoint of protein unfolding (T(m)) and unfolding enthalpy (DeltaH) of McpS-LBD. Equilibrium sedimentation studies show that malate, the chemoattractant that causes the strongest chemotactic response, stabilizes the dimeric state of McpS-LBD. In this respect clear parallels exist to the Tar receptor and other eukaryotic receptors, which are discussed.

  2. Identification and characterization of a novel gene differentially expressed in zebrafish cross-subfamily cloned embryos

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    Wang Ya-Ping

    2008-03-01

    Full Text Available Abstract Background Cross-species nuclear transfer has been shown to be a potent approach to retain the genetic viability of a certain species near extinction. However, most embryos produced by cross-species nuclear transfer were compromised because that they were unable to develop to later stages. Gene expression analysis of cross-species cloned embryos will yield new insights into the regulatory mechanisms involved in cross-species nuclear transfer and embryonic development. Results A novel gene, K31, was identified as an up-regulated gene in fish cross-subfamily cloned embryos using SSH approach and RACE method. K31 complete cDNA sequence is 1106 base pairs (bp in length, with a 342 bp open reading frame (ORF encoding a putative protein of 113 amino acids (aa. Comparative analysis revealed no homologous known gene in zebrafish and other species database. K31 protein contains a putative transmembrane helix and five putative phosphorylation sites but without a signal peptide. Expression pattern analysis by real time RT-PCR and whole-mount in situ hybridization (WISH shows that it has the characteristics of constitutively expressed gene. Sub-cellular localization assay shows that K31 protein can not penetrate the nuclei. Interestingly, over-expression of K31 gene can cause lethality in the epithelioma papulosum cyprinid (EPC cells in cell culture, which gave hint to the inefficient reprogramming events occurred in cloned embryos. Conclusion Taken together, our findings indicated that K31 gene is a novel gene differentially expressed in fish cross-subfamily cloned embryos and over-expression of K31 gene can cause lethality of cultured fish cells. To our knowledge, this is the first report on the determination of novel genes involved in nucleo-cytoplasmic interaction of fish cross-subfamily cloned embryos.

  3. A family of chemoreceptors in Tribolium castaneum (Tenebrionidae: Coleoptera.

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    Mohatmed Abdel-Latief

    Full Text Available Chemoperception in invertebrates is mediated by a family of G-protein-coupled receptors (GPCR. To date nothing is known about the molecular mechanisms of chemoperception in coleopteran species. Recently the genome of Tribolium castaneum was sequenced for use as a model species for the Coleoptera. Using blast searches analyses of the T. castaneum genome with previously predicted amino acid sequences of insect chemoreceptor genes, a putative chemoreceptor family consisting of 62 gustatory receptors (Grs and 26 olfactory receptors (Ors was identified. The receptors have seven transmembrane domains (7TMs and all belong to the GPCR receptor family. The expression of the T. castaneum chemoreceptor genes was investigated using quantification real- time RT-PCR and in situ whole mount RT-PCR analysis in the antennae, mouth parts, and prolegs of the adults and larvae. All of the predicted TcasGrs were expressed in the labium, maxillae, and prolegs of the adults but TcasGr13, 19, 28, 47, 62, 98, and 61 were not expressed in the prolegs. The TcasOrs were localized only in the antennae and not in any of the beetles gustatory organs with one exception; the TcasOr16 (like DmelOr83b, which was localized in the antennae, labium, and prolegs of the beetles. A group of six TcasGrs that presents a lineage with the sugar receptors subfamily in Drosophila melanogaster were localized in the lacinia of the Tribolium larvae. TcasGr1, 3, and 39, presented an ortholog to CO(2 receptors in D. melanogaster and Anopheles gambiae was recorded. Low expression of almost all of the predicted chemoreceptor genes was observed in the head tissues that contain the brains and suboesophageal ganglion (SOG. These findings demonstrate the identification of a chemoreceptor family in Tribolium, which is evolutionarily related to other insect species.

  4. Differential epigenetic regulation of TOX subfamily high mobility group box genes in lung and breast cancers.

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    Mathewos Tessema

    Full Text Available Aberrant cytosine methylation affects regulation of hundreds of genes during cancer development. In this study, a novel aberrantly hypermethylated CpG island in cancer was discovered within the TOX2 promoter. TOX2 was unmethylated in normal cells but 28% lung (n = 190 and 23% breast (n = 80 tumors were methylated. Expression of two novel TOX2 transcripts identified was significantly reduced in primary lung tumors than distant normal lung (p<0.05. These transcripts were silenced in methylated lung and breast cancer cells and 5-Aza-2-deoxycytidine treatment re-expressed both. Extension of these assays to TOX, TOX3, and TOX4 genes that share similar genomic structure and protein homology with TOX2 revealed distinct methylation profiles by smoking status, histology, and cancer type. TOX was almost exclusively methylated in breast (43% than lung (5% cancer, whereas TOX3 was frequently methylated in lung (58% than breast (30% tumors. TOX4 was unmethylated in all samples and showed the highest expression in normal lung. Compared to TOX4, expression of TOX, TOX2 and TOX3 in normal lung was 25, 44, and 88% lower, respectively, supporting the premise that reduced promoter activity confers increased susceptibility to methylation during lung carcinogenesis. Genome-wide assays revealed that siRNA-mediated TOX2 knockdown modulated multiple pathways while TOX3 inactivation targeted neuronal development and function. Although these knockdowns did not result in further phenotypic changes of lung cancer cells in vitro, the impact on tissue remodeling, inflammatory response, and cell differentiation pathways suggest a potential role for TOX2 in modulating tumor microenvironment.

  5. Automated protein subfamily identification and classification.

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    Duncan P Brown

    2007-08-01

    Full Text Available Function prediction by homology is widely used to provide preliminary functional annotations for genes for which experimental evidence of function is unavailable or limited. This approach has been shown to be prone to systematic error, including percolation of annotation errors through sequence databases. Phylogenomic analysis avoids these errors in function prediction but has been difficult to automate for high-throughput application. To address this limitation, we present a computationally efficient pipeline for phylogenomic classification of proteins. This pipeline uses the SCI-PHY (Subfamily Classification in Phylogenomics algorithm for automatic subfamily identification, followed by subfamily hidden Markov model (HMM construction. A simple and computationally efficient scoring scheme using family and subfamily HMMs enables classification of novel sequences to protein families and subfamilies. Sequences representing entirely novel subfamilies are differentiated from those that can be classified to subfamilies in the input training set using logistic regression. Subfamily HMM parameters are estimated using an information-sharing protocol, enabling subfamilies containing even a single sequence to benefit from conservation patterns defining the family as a whole or in related subfamilies. SCI-PHY subfamilies correspond closely to functional subtypes defined by experts and to conserved clades found by phylogenetic analysis. Extensive comparisons of subfamily and family HMM performances show that subfamily HMMs dramatically improve the separation between homologous and non-homologous proteins in sequence database searches. Subfamily HMMs also provide extremely high specificity of classification and can be used to predict entirely novel subtypes. The SCI-PHY Web server at http://phylogenomics.berkeley.edu/SCI-PHY/ allows users to upload a multiple sequence alignment for subfamily identification and subfamily HMM construction. Biologists wishing to

  6. Protein complex interactor analysis and differential activity of KDM3 subfamily members towards H3K9 methylation.

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    Michael Brauchle

    Full Text Available Histone modifications play an important role in chromatin organization and gene regulation, and their interpretation is referred to as epigenetic control. The methylation levels of several lysine residues in histone tails are tightly controlled, and JmjC domain-containing proteins are one class of broadly expressed enzymes catalyzing methyl group removal. However, several JmjC proteins remain uncharacterized, gaps persist in understanding substrate recognition, and the integration of JmjC proteins into signaling pathways is just emerging. The KDM3 subfamily is an evolutionarily conserved group of histone demethylase proteins, thought to share lysine substrate specificity. Here we use a systematic approach to compare KDM3 subfamily members. We show that full-length KDM3A and KDM3B are H3K9me1/2 histone demethylases whereas we fail to observe histone demethylase activity for JMJD1C using immunocytochemical and biochemical approaches. Structure-function analyses revealed the importance of a single amino acid in KDM3A implicated in the catalytic activity towards H3K9me1/2 that is not conserved in JMJD1C. Moreover, we use quantitative proteomic analyses to identify subsets of the interactomes of the 3 proteins. Specific interactor candidates were identified for each of the three KDM3 subfamily members. Importantly, we find that SCAI, a known transcriptional repressor, interacts specifically with KDM3B. Taken together, we identify substantial differences in the biology of KDM3 histone demethylases, namely enzymatic activity and protein-protein interactions. Such comparative approaches pave the way to a better understanding of histone demethylase specificity and protein function at a systems level and are instrumental in identifying the more subtle differences between closely related proteins.

  7. Directed Evolution of Bacterial Chemoreceptors

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    Goulian, Mark

    2006-03-01

    The methyl-accepting chemotaxis proteins are a family of receptors in bacteria that mediate chemotaxis to diverse signals. We have developed a simple method for selecting bacteria that swim towards target attractants, which makes it possible to isolate novel chemoreceptors. The procedure is based on establishing a diffusive gradient in semi-soft agar and does not require that the attractant be metabolized or degraded. We have applied this method to evolve the E. coli aspartate receptor, Tar, to mediate chemotaxis to new attractants. We found that Tar is quite plastic and can be readily mutated to respond to diverse compounds. The overall change in specificity depended on the target attractant. In some cases the mutated receptors still showed significant sensitivity to aspartate, indicating that the receptors had a broadened specificity relative to wild-type Tar. In other cases, however, the Tar variants showed a dramatic decrease in their response to aspartate. This occurred in the absence of any counter-selection steps. For many of the receptors, the maximal sensitivity that was obtained could not be attributed solely to substitutions within the ligand binding pocket. The receptors that we have isolated, together with additional variants that may be obtained with our technique, provide new tools for exploring the molecular mechanisms of signal transduction by chemoreceptors. Our selection method will also be useful for constructing new receptors for the development of biosensors and for engineering bacteria for applications in biotechnology.

  8. Differential expression of cytochrome P450 enzymes from the CYP2C subfamily in the human brain.

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    Booth Depaz, Iris M; Toselli, Francesca; Wilce, Peter A; Gillam, Elizabeth M J

    2015-03-01

    Cytochrome P450 enzymes from the CYP2C subfamily play a prominent role in the metabolic clearance of many drugs. CYP2C enzymes have also been implicated in the metabolism of arachidonic acid to vasoactive epoxyeicosatrienoic acids. CYP2C8, CYP2C9, and CYP2C19 are expressed in the adult liver at significant levels; however, the expression of CYP2C enzymes in extrahepatic tissues such as the brain is less well characterized. Form-specific antibodies to CYP2C9 and CYP2C19 were prepared by affinity purification of antibodies raised to unique peptides. CYP2C9 and CYP2C19 were located in microsomal fractions of all five human brain regions examined, namely the frontal cortex, hippocampus, basal ganglia, amygdala, and cerebellum. Both CYP2C9 and CYP2C19 were detected predominantly within the neuronal soma but with expression extending down axons and dendrites in certain regions. Finally, a comparison of cortex samples from alcoholics and age-matched controls suggested that CYP2C9 expression was increased in alcoholics.

  9. Requirement of the Carboxyl Terminus of a Bacterial Chemoreceptor for Its Targeted Proteolysis

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    Alley, M. R. K.; Maddock, Janine R.; Shapiro, Lucille

    1993-03-01

    The bacterium Caulobacter crescentus yields two different progeny at each cell division; a chemotactically competent swarmer cell and a sessile stalked cell. The chemotaxis proteins are synthesized in the predivisional cell and then partition only to the swarmer cell upon division. The chemoreceptors that were newly synthesized were located at the nascent swarmer pole of the predivisional cell, an indication that asymmetry was established prior to cell division. When the swarmer cell differentiated into a stalked cell, the chemoreceptor was specifically degraded by virtue of an amino acid sequence located at its carboxyl terminus. Thus, a temporally and spatially restricted proteolytic event was a component of this differentiation process.

  10. Identification of a Chemoreceptor for Tricarboxylic Acid Cycle Intermediates

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    Lacal, Jesús; Alfonso, Carlos; Liu, Xianxian; Parales, Rebecca E.; Morel, Bertrand; Conejero-Lara, Francisco; Rivas, Germán; Duque, Estrella; Ramos, Juan L.; Krell, Tino

    2010-01-01

    We report the identification of McpS as the specific chemoreceptor for 6 tricarboxylic acid (TCA) cycle intermediates and butyrate in Pseudomonas putida. The analysis of the bacterial mutant deficient in mcpS and complementation assays demonstrate that McpS is the only chemoreceptor of TCA cycle intermediates in the strain under study. TCA cycle intermediates are abundantly present in root exudates, and taxis toward these compounds is proposed to facilitate the access to carbon sources. McpS has an unusually large ligand-binding domain (LBD) that is un-annotated in InterPro and is predicted to contain 6 helices. The ligand profile of McpS was determined by isothermal titration calorimetry of purified recombinant LBD (McpS-LBD). McpS recognizes TCA cycle intermediates but does not bind very close structural homologues and derivatives like maleate, aspartate, or tricarballylate. This implies that functional similarity of ligands, such as being part of the same pathway, and not structural similarity is the primary element, which has driven the evolution of receptor specificity. The magnitude of chemotactic responses toward these 7 chemoattractants, as determined by qualitative and quantitative chemotaxis assays, differed largely. Ligands that cause a strong chemotactic response (malate, succinate, and fumarate) were found by differential scanning calorimetry to increase significantly the midpoint of protein unfolding (Tm) and unfolding enthalpy (ΔH) of McpS-LBD. Equilibrium sedimentation studies show that malate, the chemoattractant that causes the strongest chemotactic response, stabilizes the dimeric state of McpS-LBD. In this respect clear parallels exist to the Tar receptor and other eukaryotic receptors, which are discussed. PMID:20498372

  11. Chemoreceptor stimulation interferes with regional hypoxic pulmonary vasoconstriction.

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    Chapleau, M W; Wilson, L B; Gregory, T J; Levitzky, M G

    1988-02-01

    Hypoxemia interferes with the diversion of blood flow away from hypoxic regions of the lung, possibly through activation of the arterial chemoreceptor reflex. The purpose of this study was to determine if selective stimulation of carotid chemoreceptors reduces the diversion of flow (hypoxic vasoconstriction) when normal systemic oxygen levels are present. Chloralose anesthetized dogs were paralyzed and each lung was separately ventilated via a dual-lumen endobronchial tube. Left pulmonary artery (QL) and main pulmonary artery (QT) blood flows were measured with electromagnetic flow probes. Chemoreceptors were stimulated by perfusion of the carotid sinuses with hypoxic, hypercapnic blood. QL/QT averaged 46 +/- 4, 29 +/- 2, and 36 +/- 4% during bilateral O2 ventilation (control), left lung N2 ventilation, and left lung N2 plus chemoreceptor stimulation in dogs treated with the cyclo-oxygenase inhibitor meclofenamate. After vagotomy, QL/QT averaged 45 +/- 4, 27 +/- 3, and 28 +/- 2% during the same conditions. QL/QT decreased significantly from control (P less than 0.05) during left lung N2 alone but did not decrease during left lung N2 plus chemoreceptor stimulation in dogs with intact vagi. In contrast, QL/QT decreased significantly both before and during chemoreceptor stimulation in vagotomized dogs. The same responses were observed in dogs not treated with meclofenamate. These results indicate that selective stimulation of arterial chemoreceptors can interfere with regional hypoxic vasoconstriction and suggest that the vagus nerves may mediate this effect.

  12. Caste-Specific and Sex-Specific Expression of Chemoreceptor Genes in a Termite.

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    Yuki Mitaka

    Full Text Available The sophisticated colony organization of eusocial insects is primarily maintained through the utilization of pheromones. The regulation of these complex social interactions requires intricate chemoreception systems. The recent publication of the genome of Zootermopsis nevadensis opened a new avenue to study molecular basis of termite caste systems. Although there has been a growing interest in the termite chemoreception system that regulates their sophisticated caste system, the relationship between division of labor and expression of chemoreceptor genes remains to be explored. Using high-throughput mRNA sequencing (RNA-seq, we found several chemoreceptors that are differentially expressed among castes and between sexes in a subterranean termite Reticulitermes speratus. In total, 53 chemoreception-related genes were annotated, including 22 odorant receptors, 7 gustatory receptors, 12 ionotropic receptors, 9 odorant-binding proteins, and 3 chemosensory proteins. Most of the chemoreception-related genes had caste-related and sex-related expression patterns; in particular, some chemoreception genes showed king-biased or queen-biased expression patterns. Moreover, more than half of the genes showed significant age-dependent differences in their expression in female and/or male reproductives. These results reveal a strong relationship between the evolution of the division of labor and the regulation of chemoreceptor gene expression, thereby demonstrating the chemical communication and underlining chemoreception mechanism in social insects.

  13. Caste-Specific and Sex-Specific Expression of Chemoreceptor Genes in a Termite.

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    Mitaka, Yuki; Kobayashi, Kazuya; Mikheyev, Alexander; Tin, Mandy M Y; Watanabe, Yutaka; Matsuura, Kenji

    2016-01-01

    The sophisticated colony organization of eusocial insects is primarily maintained through the utilization of pheromones. The regulation of these complex social interactions requires intricate chemoreception systems. The recent publication of the genome of Zootermopsis nevadensis opened a new avenue to study molecular basis of termite caste systems. Although there has been a growing interest in the termite chemoreception system that regulates their sophisticated caste system, the relationship between division of labor and expression of chemoreceptor genes remains to be explored. Using high-throughput mRNA sequencing (RNA-seq), we found several chemoreceptors that are differentially expressed among castes and between sexes in a subterranean termite Reticulitermes speratus. In total, 53 chemoreception-related genes were annotated, including 22 odorant receptors, 7 gustatory receptors, 12 ionotropic receptors, 9 odorant-binding proteins, and 3 chemosensory proteins. Most of the chemoreception-related genes had caste-related and sex-related expression patterns; in particular, some chemoreception genes showed king-biased or queen-biased expression patterns. Moreover, more than half of the genes showed significant age-dependent differences in their expression in female and/or male reproductives. These results reveal a strong relationship between the evolution of the division of labor and the regulation of chemoreceptor gene expression, thereby demonstrating the chemical communication and underlining chemoreception mechanism in social insects.

  14. Changing the specificity of a bacterial chemoreceptor.

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    Derr, Paige; Boder, Eric; Goulian, Mark

    2006-02-01

    The methyl-accepting chemotaxis proteins are a family of receptors in bacteria that mediate chemotaxis to diverse signals. To explore the plasticity of these proteins, we have developed a simple method for selecting cells that swim to target attractants. The procedure is based on establishing a diffusive gradient in semi-soft agar plates and does not require that the attractant be metabolized or degraded. We have applied this method to select for variants of the Escherichia coli aspartate receptor, Tar, that have a new or improved response to different amino acids. We found that Tar can be readily mutated to respond to new chemical signals. However, the overall change in specificity depended on the target compound. A Tar variant that could detect cysteic acid still showed a strong sensitivity to aspartate, indicating that the new receptor had a broadened specificity relative to wild-type Tar. Tar variants that responded to phenylalanine or N-methyl aspartate, or that had an increased sensitivity to glutamate showed a strong decrease in their response to aspartate. In at least some of the cases, the maximal level of sensitivity that was obtained could not be attributed solely to substitutions within the binding pocket. The new tar alleles and the techniques described here provide a new approach for exploring the relationship between ligand binding and signal transduction by chemoreceptors and for engineering new receptors for applications in biotechnology.

  15. Sinorhizobium meliloti chemotaxis to quaternary ammonium compounds is mediated by the chemoreceptor McpX.

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    Webb, Benjamin A; Karl Compton, K; Castañeda Saldaña, Rafael; Arapov, Timofey D; Keith Ray, W; Helm, Richard F; Scharf, Birgit E

    2017-01-01

    The bacterium Sinorhizobium meliloti is attracted to seed exudates of its host plant alfalfa (Medicago sativa). Since quaternary ammonium compounds (QACs) are exuded by germinating seeds, we assayed chemotaxis of S. meliloti towards betonicine, choline, glycine betaine, stachydrine and trigonelline. The wild type displayed a positive response to all QACs. Using LC-MS, we determined that each germinating alfalfa seed exuded QACs in the nanogram range. Compared to the closely related nonhost species, spotted medic (Medicago arabica), unique profiles were released. Further assessments of single chemoreceptor deletion strains revealed that an mcpX deletion strain displayed little to no response to these compounds. Differential scanning fluorimetry showed interaction of the isolated periplasmic region of McpX (McpX(PR) and McpX34-306 ) with QACs. Isothermal titration calorimetry experiments revealed tight binding to McpX(PR) with dissociation constants (Kd ) in the nanomolar range for choline and glycine betaine, micromolar Kd for stachydrine and trigonelline and a Kd in the millimolar range for betonicine. Our discovery of S. meliloti chemotaxis to plant-derived QACs adds another role to this group of compounds, which are known to serve as nutrient sources, osmoprotectants and cell-to-cell signalling molecules. This is the first report of a chemoreceptor that mediates QACs taxis through direct binding.

  16. Effect of chemoreceptor denervation on the pulmonary vascular response to atelectasis.

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    Levitzky, M G; Newell, J C; Dutton, R E

    1978-10-01

    Six dogs anesthetized with 30 mg/kg pentobarbital were ventilated after differential cannulation of the main stem bronchi. Following sternotomy, blood flow was monitored by electromagnetic flow probes on the left pulmonary artery (QL) and on the pulmonary trunk or aorta (QT). Following 10 min of bilateral 100% O2, QL was 37.4 +/- 5.8% of QT. When left lung atelectasis was induced while the right lung remained on 100% O2, PaO2 remained above 75 mm Hg and QL fell to 26.1 +/- 5.0% of QT. However, when the right lung was ventilated with room air while the left lung remained atelectatic, PaO2 fell to 50.0 +/- 2.6 mm Hg and QL rose to 36.7 +/- 6.2% of QT. Six dogs which had undergone peripheral chemoreceptor denervation prior to these experiments showed a similar decrease in perfusion of the atelectatic left lung when the right lung was ventilated with 100% O2, but did not increase blood flow to the atelectatic lung during systemic hypoxemia. Thus, the increased blood flow to the atelectatic lung which occurs during systemic hypoxemia appears to be mediated by the arterial chemoreceptors.

  17. Chemoreceptor influence on pulmonary blood flow during unilateral hypoxia in dogs.

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    Levitzky, M G; Newell, J C; Krasney, J A; Dutton, R E

    1977-12-01

    Dogs anesthetized with 30 mg/kg pentobarbital were artificially respired after differential cannulation of the main stem bronchi. Following median sternotomy, blood flow was monitored by electromagnetic flow probes on the left pulmonary artery (QL) and on the pulmonary trunk or aorta, QT. Following 10 min of bilateral 100% O2, QL was 42.5 +/- 7% of QT. When 6% O2, was substituted as the gas mixture inspired by the left lung while the right lung remained on 100% O2, PaO2 was above 70 mm Hg and QL fell to 24.5 +/- 5% of QT. Room air was then used to ventilate the right lung while the left lung remained on 6% O2. This caused PaO2 to fall to 42.3 +/- 3 MM Hg and QL to rise to 38.3 +/- 6% QT. This increase in blood flow to the unilaterally hypoxic lung during systemic hypoxemia did not occur in dogs after peripheral chemoreceptor denervation. Therefore, interference with the local response to alveolar hypoxia during systemic hypoxemia appears to be mediated by the arterial chemoreceptors.

  18. Contribution of Individual Chemoreceptors to Sinorhizobium meliloti Chemotaxis Towards Amino Acids of Host and Nonhost Seed Exudates.

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    Webb, Benjamin A; Helm, Richard F; Scharf, Birgit E

    2016-03-01

    Plant seeds and roots exude a spectrum of molecules into the soil that attract bacteria to the spermosphere and rhizosphere, respectively. The alfalfa symbiont Sinorhizobium meliloti utilizes eight chemoreceptors (McpT to McpZ and IcpA) to mediate chemotaxis. Using a modified hydrogel capillary chemotaxis assay that allows data quantification and larger throughput screening, we defined the role of S. meliloti chemoreceptors in sensing its host, Medicago sativa, and a closely related nonhost, Medicago arabica. S. meliloti wild type and most single-deletion strains displayed comparable chemotaxis responses to host or nonhost seed exudate. However, while the mcpZ mutant responded like wild type to M. sativa exudate, its reaction to M. arabica exudate was reduced by 80%. Even though the amino acid (AA) amounts released by both plant species were similar, synthetic AA mixtures that matched exudate profiles contributed differentially to the S. meliloti wild-type response to M. sativa (23%) and M. arabica (37%) exudates, with McpU identified as the most important chemoreceptor for AA. Our results show that S. meliloti is equally attracted to host and nonhost legumes; however, AA play a greater role in attraction to M. arabica than to M. sativa, with McpZ being specifically important in sensing M. arabica.

  19. Chemicals and chemoreceptors: ecologically relevant signals driving behavior in Drosophila.

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    Ana eDepetris-Chauvin

    2015-04-01

    Full Text Available Insects encounter a vast repertoire of chemicals in their natural environment, which can signal positive stimuli like the presence of a food source, a potential mate, or a suitable oviposition site as well as negative stimuli such as competitors, predators, or toxic substances reflecting danger. The presence of specialized chemoreceptors like taste and olfactory receptors allow animals to detect chemicals at short and long distances and accordingly, trigger proper behaviors towards these stimuli. Since the first description of olfactory and taste receptors in Drosophila fifteen years ago, our knowledge on the identity, properties, and function of specific chemoreceptors has increased exponentially. In the last years, multidisciplinary approaches combining genetic tools with electrophysiological techniques, behavioral recording, evolutionary analysis, and chemical ecology studies are shedding light on our understanding on the ecological relevance of specific chemoreceptors for the survival of Drosophila in their natural environment. In this review we discuss the current knowledge on chemoreceptors of both the olfactory and taste systems of the fruitfly. We focus on the relevance of particular receptors for the detection of ecologically relevant cues such as pheromones, food sources, and toxic compounds, and we comment on the behavioral changes that the detection of these chemicals induce in the fly. In particular, we give an updated outlook of the chemical communication displayed during one of the most important behaviors for fly survival, the courtship behavior. Finally, the ecological relevance of specific chemicals can vary depending on the niche occupied by the individual. In that regard, in this review we also highlight the contrast between adult and larval systems and we propose that these differences could reflect distinctive requirements depending on the change of ecological niche occupied by Drosophila along its life cycle.

  20. Analysis of putative chemoreceptor proteins of Campylobacter jejuni

    DEFF Research Database (Denmark)

    Vegge, Christina Skovgaard; Brøndsted, Lone; Bang, Dang D.

    Campylobacter jejuni is the primary food borne bacterial pathogen in the developed world. A very important reservoir for C. jejuni is the gut of chickens, which are colonized efficiently and commensally by this organism. Predominantly the mucus filled crypts of the lower gastrointestinal tract...... are being analyzed in adherence and invasion assays with both human and chicken cells to explore the possibility that these membrane spanning proteins interact with host cells rather than operating as chemoreceptors....

  1. Central chemoreceptors and neural mechanisms of cardiorespiratory control

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    T.S. Moreira

    2011-09-01

    Full Text Available The arterial partial pressure (P CO2 of carbon dioxide is virtually constant because of the close match between the metabolic production of this gas and its excretion via breathing. Blood gas homeostasis does not rely solely on changes in lung ventilation, but also to a considerable extent on circulatory adjustments that regulate the transport of CO2 from its sites of production to the lungs. The neural mechanisms that coordinate circulatory and ventilatory changes to achieve blood gas homeostasis are the subject of this review. Emphasis will be placed on the control of sympathetic outflow by central chemoreceptors. High levels of CO2 exert an excitatory effect on sympathetic outflow that is mediated by specialized chemoreceptors such as the neurons located in the retrotrapezoid region. In addition, high CO2 causes an aversive awareness in conscious animals, activating wake-promoting pathways such as the noradrenergic neurons. These neuronal groups, which may also be directly activated by brain acidification, have projections that contribute to the CO2-induced rise in breathing and sympathetic outflow. However, since the level of activity of the retrotrapezoid nucleus is regulated by converging inputs from wake-promoting systems, behavior-specific inputs from higher centers and by chemical drive, the main focus of the present manuscript is to review the contribution of central chemoreceptors to the control of autonomic and respiratory mechanisms.

  2. Sinorhizobium meliloti chemoreceptor McpU mediates chemotaxis toward host plant exudates through direct proline sensing.

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    Webb, Benjamin A; Hildreth, Sherry; Helm, Richard F; Scharf, Birgit E

    2014-06-01

    Bacterial chemotaxis is an important attribute that aids in establishing symbiosis between rhizobia and their legume hosts. Plant roots and seeds exude a spectrum of molecules into the soil to attract their bacterial symbionts. The alfalfa symbiont Sinorhizobium meliloti possesses eight chemoreceptors to sense its environment and mediate chemotaxis toward its host. The methyl accepting chemotaxis protein McpU is one of the more abundant S. meliloti chemoreceptors and an important sensor for the potent attractant proline. We established a dominant role of McpU in sensing molecules exuded by alfalfa seeds. Mass spectrometry analysis determined that a single germinating seed exudes 3.72 nmol of proline, producing a millimolar concentration near the seed surface which can be detected by the chemosensory system of S. meliloti. Complementation analysis of the mcpU deletion strain verified McpU as the key proline sensor. A structure-based homology search identified tandem Cache (calcium channels and chemotaxis receptors) domains in the periplasmic region of McpU. Conserved residues Asp-155 and Asp-182 of the N-terminal Cache domain were determined to be important for proline sensing by evaluating mutant strains in capillary and swim plate assays. Differential scanning fluorimetry revealed interaction of the isolated periplasmic region of McpU (McpU40-284) with proline and the importance of Asp-182 in this interaction. Using isothermal titration calorimetry, we determined that proline binds with a Kd (dissociation constant) of 104 μM to McpU40-284, while binding was abolished when Asp-182 was substituted by Glu. Our results show that McpU is mediating chemotaxis toward host plants by direct proline sensing.

  3. Chemoreceptors and cardiovascular control in acute and chronic systemic hypoxia

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    J.M. Marshall

    1998-07-01

    Full Text Available This review describes the ways in which the primary bradycardia and peripheral vasoconstriction evoked by selective stimulation of peripheral chemoreceptors can be modified by the secondary effects of a chemoreceptor-induced increase in ventilation. The evidence that strong stimulation of peripheral chemoreceptors can evoke the behavioural and cardiovascular components of the alerting or defence response which is characteristically evoked by novel or noxious stimuli is considered. The functional significance of all these influences in systemic hypoxia is then discussed with emphasis on the fact that these reflex changes can be overcome by the local effects of hypoxia: central neural hypoxia depresses ventilation, hypoxia acting on the heart causes bradycardia and local hypoxia of skeletal muscle and brain induces vasodilatation. Further, it is proposed that these local influences can become interdependent, so generating a positive feedback loop that may explain sudden infant death syndrome (SIDS. It is also argued that a major contributor to these local influences is adenosine. The role of adenosine in determining the distribution of O2 in skeletal muscle microcirculation in hypoxia is discussed, together with its possible cellular mechanisms of action. Finally, evidence is presented that in chronic systemic hypoxia, the reflex vasoconstrictor influences of the sympathetic nervous system are reduced and/or the local dilator influences of hypoxia are enhanced. In vitro and in vivo findings suggest this is partly explained by upregulation of nitric oxide (NO synthesis by the vascular endothelium which facilitates vasodilatation induced by adenosine and other NO-dependent dilators and attenuates noradrenaline-evoked vasoconstriction.

  4. Sequences determining the cytoplasmic localization of a chemoreceptor domain.

    Science.gov (United States)

    Seligman, L; Bailey, J; Manoil, C

    1995-01-01

    The Escherichia coli serine chemoreceptor (Tsr) is a protein with a simple topology consisting of two membrane-spanning sequences (TM1 and TM2) separating a large periplasmic domain from N-terminal and C-terminal cytoplasmic regions. We analyzed the contributions of several sequence elements to the cytoplasmic localization of the C-terminal domain by using chemoreceptor-alkaline phosphatase gene fusions. The principal findings were as follows. (i) The cytoplasmic localization of the C-terminal domain depended on TM2 but was quite tolerant of mutations partially deleting or introducing charged residues into the sequence. (ii) The basal level of C-terminal domain export was significantly higher in proteins with the wild-type periplasmic domain than in derivatives with a shortened periplasmic domain, suggesting that the large size of the wild-type domain promotes partial membrane misinsertion. (iii) The membrane insertion of deletion derivatives with a single spanning segment (TM1 or TM2) could be controlled by either an adjacent positively charged sequence or an adjacent amphipathic sequence. The results provide evidence that the generation of the Tsr membrane topology is an overdetermined process directed by an interplay of sequences promoting and opposing establishment of the normal structure. PMID:7730259

  5. Chemoreceptor stimulation and hypoxic pulmonary vasoconstriction in conscious dogs.

    Science.gov (United States)

    Levitzky, M G

    1979-07-01

    Dogs with electromagnetic flow probes implanted on their left (QL) and main (QT) pulmonary arteries, catheters in their left atria and external jugular veins, and chronic tracheostomies were trained to accept Carlens dual-lumen endotracheal tubes into their tracheostomies, thus allowing separate ventilation of the two lungs. Swan-Ganz catheters were inserted through the jugular vein catheters. Pneumotachographs measured air flow to each lung. During bilateral ventilation with room air or O2, QL was about 36% of QT. When the left lung was ventilated with N2 while the right remained on O2, PAO2 was above 90 mmHg and QL fell to about 25% of QT. When the left lung was ventilated with N2 and the right with room air, PAO2 fell below 40 mm Hg and QL increased to control levels. This increase in perfusion of the hypoxic lung during systemic hypoxemia was not seen in dogs after surgical deafferentation of the systemic arterial chemoreceptors, indicating that stimulation of the arterial chemoreceptors may interfere with the hypoxic pulmonary vasoconstriction.

  6. Interaction of chemoreceptor and baroreceptor reflexes by hypoxia and hypercapnia - a mechanism for promoting hypertension in obstructive sleep apnoea.

    Science.gov (United States)

    Cooper, V L; Pearson, S B; Bowker, C M; Elliott, M W; Hainsworth, R

    2005-10-15

    Asphyxia, which occurs during obstructive sleep apnoeic events, alters the baroreceptor reflex and this may lead to hypertension. We have recently reported that breathing an asphyxic gas resets the baroreceptor-vascular resistance reflex towards higher pressures. The present study was designed to determine whether this effect was caused by the reduced oxygen tension, which affects mainly peripheral chemoreceptors, or by the increased carbon dioxide, which acts mainly on central chemoreceptors. We studied 11 healthy volunteer subjects aged between 20 and 55 years old (6 male). The stimulus to the carotid baroreceptors was changed using graded pressures of -40 to +60 mmHg applied to a neck chamber. Responses of vascular resistance were assessed in the forearm from changes in blood pressure (Finapres) divided by brachial blood flow velocity (Doppler) and cardiac responses from the changes in RR interval and heart rate. Stimulus-response curves were defined during (i) air breathing, (ii) hypoxia (12% O(2) in N(2)), and (iii) hypercapnia (5% CO(2) in 95% O(2)). Responses during air breathing were assessed both prior to and after either hypoxia or hypercapnia. We applied a sigmoid function or third order polynomial to the curves and determined the maximal differential (equivalent to peak sensitivity) and the corresponding carotid sinus pressure (equivalent to 'set point'). Hypoxia resulted in an increase in heart rate but no significant change in mean blood pressure or vascular resistance. However, there was an increase in vascular resistance in the post-stimulus period. Hypoxia had no significant effect on baroreflex sensitivity or 'set point' for the control of RR interval, heart rate or mean arterial pressure. Peak sensitivity of the vascular resistance response to baroreceptor stimulation was significantly reduced from -2.5 +/- 0.4 units to -1.4 +/- 0.1 units (P sleep apnoea.

  7. Functional analysis of nine putative chemoreceptor proteins in Sinorhizobium meliloti.

    Science.gov (United States)

    Meier, Veronika M; Muschler, Paul; Scharf, Birgit E

    2007-03-01

    The genome of the symbiotic soil bacterium Sinorhizobium meliloti contains eight genes coding for methyl-accepting chemotaxis proteins (MCPs) McpS to McpZ and one gene coding for a transducer-like protein, IcpA. Seven of the MCPs are localized in the cytoplasmic membrane via two membrane-spanning regions, whereas McpY and IcpA lack such hydrophobic regions. The periplasmic regions of McpU, McpV, and McpX contain the small-ligand-binding domain Cache. In addition, McpU possesses the ligand-binding domain TarH. By probing gene expression with lacZ fusions, we have identified mcpU and mcpX as being highly expressed. Deletion of any one of the receptor genes caused impairments in the chemotactic response toward most organic acids, amino acids, and sugars in a swarm plate assay. The data imply that chemoreceptor proteins in S. meliloti can sense more than one class of carbon source and suggest that many or all receptors work as an ensemble. Tactic responses were virtually eliminated for a strain lacking all nine receptor genes. Capillary assays revealed three important sensors for the strong attractant proline: McpU, McpX, and McpY. Receptor deletions variously affected free-swimming speed and attractant-induced chemokinesis. Noticeably, cells lacking mcpU were swimming 9% slower than the wild-type control. We infer that McpU inhibits the kinase activity of CheA in the absence of an attractant. Cells lacking one of the two soluble receptors were impaired in chemokinetic proficiency by more than 50%. We propose that the internal sensors, IcpA and the PAS domain containing McpY, monitor the metabolic state of S. meliloti.

  8. Hydrogen sulfide activates the carotid body chemoreceptors in cat, rabbit and rat ex vivo preparations.

    Science.gov (United States)

    Jiao, Yingfu; Li, Qian; Sun, Biying; Zhang, Guohua; Rong, Weifang

    2015-03-01

    We and others previously reported experimental evidence suggesting an important role for hydrogen sulfide (H2S) in oxygen sensing in murine carotid body chemoreceptors. More recent data implicated abnormal H2S-mediated chemoreceptor signaling in pathological conditions such as chronic heart failure and hypertension. However, the idea of H2S as a mediator of oxygen-sensing in chemoreceptors has been challenged. In particular, it was shown that exogenous H2S inhibited the release of neurotransmitters (ACh and ATP) from the cat carotid body, raising the possibility that there exists significant species difference in H2S-mediated signaling in chemoreceptors. This study was designed specifically to determine the effect of H2S on chemoreceptors in different species. We conducted multiunit extracellular recordings of the sinus nerve in the ex vivo carotid body preparation taken from the rat, the cat and the rabbit. As observed in the mouse carotid body, H2S donors (NaHS or Na2S) evoked qualitatively similar excitatory responses of the afferent sinus nerves of the species studied here. The excitatory effects of the H2S donors were concentration-dependent and reversible. The sinus nerve responses to H2S donors were prevented by blockade of the transmission between type I cells and the afferent terminals, as was the response to hypoxia. These results demonstrate that exogenous H2S exerts qualitatively similar excitatory effects on chemoreceptor afferents of different species. The role of endogenous H2S-mediated signaling in carotid body function in different species awaits further investigation.

  9. Actions and mode of actions of FGF19 subfamily members.

    Science.gov (United States)

    Fukumoto, Seiji

    2008-03-01

    Fibroblast growth factors (FGFs) are humoral factors with diverse biological functions. While most FGFs were shown to work as local factors regulating cell growth and differentiation, recent investigations indicated that FGF19 subfamily members, FGF15/19, FGF21 and FGF23 work as systemic factors. FGF15/19 produced by intestine inhibits bile acid synthesis and FGF21from liver is involved in carbohydrate and lipid metabolism. In addition, FGF23 was shown to be produced by bone and regulate phosphate and vitamin D metabolism. Furthermore, these FGFs require klotho or betaklotho for their actions in addition to canonical FGF receptors. It is possible that these FGFs together with their receptor systems might be targets for novel therapeutic measures in the future.

  10. RNA-Seq Analysis of Human Trigeminal and Dorsal Root Ganglia with a Focus on Chemoreceptors.

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    Caroline Flegel

    Full Text Available The chemosensory capacity of the somatosensory system relies on the appropriate expression of chemoreceptors, which detect chemical stimuli and transduce sensory information into cellular signals. Knowledge of the complete repertoire of the chemoreceptors expressed in human sensory ganglia is lacking. This study employed the next-generation sequencing technique (RNA-Seq to conduct the first expression analysis of human trigeminal ganglia (TG and dorsal root ganglia (DRG. We analyzed the data with a focus on G-protein coupled receptors (GPCRs and ion channels, which are (potentially involved in chemosensation by somatosensory neurons in the human TG and DRG. For years, transient receptor potential (TRP channels have been considered the main group of receptors for chemosensation in the trigeminal system. Interestingly, we could show that sensory ganglia also express a panel of different olfactory receptors (ORs with putative chemosensory function. To characterize OR expression in more detail, we performed microarray, semi-quantitative RT-PCR experiments, and immunohistochemical staining. Additionally, we analyzed the expression data to identify further known or putative classes of chemoreceptors in the human TG and DRG. Our results give an overview of the major classes of chemoreceptors expressed in the human TG and DRG and provide the basis for a broader understanding of the reception of chemical cues.

  11. Positive selection in extra cellular domains in the diversification of Strigamia maritima chemoreceptors

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    Francisca C Almeida

    2015-07-01

    Full Text Available The recent publication of a centipede (Strigamia maritima genome has revealed that most members of the chemosensory gene families of ionotropic (IR and gustatory (GR receptors do not have identifiable orthologs in insect species. In other words, the diversity of these chemoreceptors in centipedes appears to have evolved after its split from other arthropod lineages. Here we investigate the role of adaptive evolution in S. maritima chemoreceptor diversification using an approach that allows us to discuss functional aspects of such diversification. We applied codon substitution models in a phylogenetic framework to obtain the distribution of selective constraints across the different domains in the IR and GR proteins, and to assess the impact of positive selection in the evolution of these chemoreceptors. We found low selective constraints in most IR and GR duplicates and significant evidence for the presence of positively selected amino acids in 2 of the 4 IR, and in 6 of the GR recent specific expansions. Mapping the sites with high posterior probability of positive selection in protein structure revealed a remarkable uneven distribution of fast-evolving sites across protein domains. Most of these sites are located in extracellular fragments of these receptors, which likely participate in ligand recognition. We hypothesize that adaptive evolution in ligand-binding domains was a major force driving the functional diversification of centipede chemoreceptors.

  12. Tetrahymena metallothioneins fall into two discrete subfamilies.

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    Silvia Díaz

    Full Text Available BACKGROUND: Metallothioneins are ubiquitous small, cysteine-rich, multifunctional proteins which can bind heavy metals. METHODOLOGY/PRINCIPAL FINDINGS: We report the results of phylogenetic and gene expression analyses that include two new Tetrahymena thermophila metallothionein genes (MTT3 and MTT5. Sequence alignments of all known Tetrahymena metallothioneins have allowed us to rationalize the structure of these proteins. We now formally subdivide the known metallothioneins from the ciliate genus Tetrahymena into two well defined subfamilies, 7a and 7b, based on phylogenetic analysis, on the pattern of clustering of Cys residues, and on the pattern of inducibility by the heavy metals Cd and Cu. Sequence alignment also reveals a remarkably regular, conserved and hierarchical modular structure of all five subfamily 7a MTs, which include MTT3 and MTT5. The former has three modules, while the latter has only two. Induction levels of the three T. thermophila genes were determined using quantitative real time RT-PCR. Various stressors (including heavy metals brought about dramatically different fold-inductions for each gene; MTT5 showed the highest fold-induction. Conserved DNA motifs with potential regulatory significance were identified, in an unbiased way, upstream of the start codons of subfamily 7a MTs. EST evidence for alternative splicing in the 3' UTR of the MTT5 mRNA with potential regulatory activity is reported. CONCLUSION/SIGNIFICANCE: The small number and remarkably regular structure of Tetrahymena MTs, coupled with the experimental tractability of this model organism for studies of in vivo function, make it an attractive system for the experimental dissection of the roles, structure/function relationships, regulation of gene expression, and adaptive evolution of these proteins, as well as for the development of biotechnological applications for the environmental monitoring of toxic substances.

  13. Seed morphology and anatomy and its utility in recognizing subfamilies and tribes of Zingiberaceae

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    Benedict, John C.; Smith, Selena Y.; Collinson, Margaret E.; Leong-Skornickova, Jana; Specht, Chelsea D.; Marone, Federica; Xiao, Xianghui; Parkinson, Dilworth Y.

    2015-11-01

    PREMISE OF THE STUDY: Recent phylogenetic analyses based on molecular data suggested that the monocot family Zingiberaceae be separated into four subfamilies and four tribes. Robust morphological characters to support these clades are lacking. Seeds were analyzed in a phylogenetic context to test independently the circumscription of clades and to better understand evolution of seed characters within Zingiberaceae. METHODS: Seventy-five species from three of the four subfamilies were analyzed using synchrotron based x-ray tomographic microscopy (SRXTM) and scored for 39 morphoanatomical characters. KEY RESULTS: Zingiberaceae seeds are some of the most structurally complex seeds in angiosperms. No single seed character was found to distinguish each subfamily, but combinations of characters were found to differentiate between the subfamilies. Recognition of the tribes based on seeds was possible for Globbeae, but not for Alpinieae, Riedelieae, or Zingibereae, due to considerable variation. CONCLUSIONS: SRXTM is an excellent, nondestructive tool to capture morphoanatomical variation of seeds and allows for the study of taxa with limited material available. Alpinioideae, Siphonochiloideae, Tamijioideae, and Zingiberoideae are well supported based on both molecular and morphological data, including multiple seed characters. Globbeae are well supported as a distinctive tribe within the Zingiberoideae, but no other tribe could be differentiated using seeds due to considerable homoplasy when compared with currently accepted relationships based on molecular data. Novel seed characters suggest tribal affinities for two currently unplaced Zingiberaceae taxa: Siliquamomum may be related to Riedelieae and Monolophus to Zingibereae, but further work is needed before formal revision of the family.

  14. Estimating diversence times among subfamilies in Nymphalidae

    Institute of Scientific and Technical Information of China (English)

    ZHANG Min; CAO TianWen; JIN Ke; REN ZhuMei; GUO YaPing; SHI Jing; ZHONG Yang; MA EnBo

    2008-01-01

    The mitochondrial cytochrome oxidase subunit I (COI) gene and the nuclear elongation factor 1α (EF-1α) gene were sequenced from 13 species of Nymphalidae. Phylogenetic trees of Nymphalidae, which is the largest family in butterflies, were constructed based on the sequences determined from 13 species sequenced in our laboratory and an additional 43 species obtained from GenBank using the maximum likelihood (ML) and Bayesian methods. Relative-rate tests between lineages in these phylogenetic trees were performed. On the basis of the results of the relative-rate tests and fossil information of Satyrinae, Nymphalinae and Biblidinae, the average divergence times among the subfamilies are estimated as 44.2-87.1 million years ago (Ma). These results will be helpful for better understanding of the origin and evolution of this family, as well as the divergence time of butterflies and other complex taxa.

  15. Functional coupling of a nematode chemoreceptor to the yeast pheromone response pathway.

    Science.gov (United States)

    Tehseen, Muhammad; Dumancic, Mira; Briggs, Lyndall; Wang, Jian; Berna, Amalia; Anderson, Alisha; Trowell, Stephen

    2014-01-01

    Sequencing of the Caenorhabditis elegans genome revealed sequences encoding more than 1,000 G-protein coupled receptors, hundreds of which may respond to volatile organic ligands. To understand how the worm's simple olfactory system can sense its chemical environment there is a need to characterise a representative selection of these receptors but only very few receptors have been linked to a specific volatile ligand. We therefore set out to design a yeast expression system for assigning ligands to nematode chemoreceptors. We showed that while a model receptor ODR-10 binds to C. elegans Gα subunits ODR-3 and GPA-3 it cannot bind to yeast Gα. However, chimaeras between the nematode and yeast Gα subunits bound to both ODR-10 and the yeast Gβγ subunits. FIG2 was shown to be a superior MAP-dependent promoter for reporter expression. We replaced the endogenous Gα subunit (GPA1) of the Saccharomyces cerevisiae (ste2Δ sst2Δ far1Δ) triple mutant ("Cyb") with a Gpa1/ODR-3 chimaera and introduced ODR-10 as a model nematode GPCR. This strain showed concentration-dependent activation of the yeast MAP kinase pathway in the presence of diacetyl, the first time that the native form of a nematode chemoreceptor has been functionally expressed in yeast. This is an important step towards en masse de-orphaning of C. elegans chemoreceptors.

  16. Functional coupling of a nematode chemoreceptor to the yeast pheromone response pathway.

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    Muhammad Tehseen

    Full Text Available Sequencing of the Caenorhabditis elegans genome revealed sequences encoding more than 1,000 G-protein coupled receptors, hundreds of which may respond to volatile organic ligands. To understand how the worm's simple olfactory system can sense its chemical environment there is a need to characterise a representative selection of these receptors but only very few receptors have been linked to a specific volatile ligand. We therefore set out to design a yeast expression system for assigning ligands to nematode chemoreceptors. We showed that while a model receptor ODR-10 binds to C. elegans Gα subunits ODR-3 and GPA-3 it cannot bind to yeast Gα. However, chimaeras between the nematode and yeast Gα subunits bound to both ODR-10 and the yeast Gβγ subunits. FIG2 was shown to be a superior MAP-dependent promoter for reporter expression. We replaced the endogenous Gα subunit (GPA1 of the Saccharomyces cerevisiae (ste2Δ sst2Δ far1Δ triple mutant ("Cyb" with a Gpa1/ODR-3 chimaera and introduced ODR-10 as a model nematode GPCR. This strain showed concentration-dependent activation of the yeast MAP kinase pathway in the presence of diacetyl, the first time that the native form of a nematode chemoreceptor has been functionally expressed in yeast. This is an important step towards en masse de-orphaning of C. elegans chemoreceptors.

  17. Synaptic transmission of baro- and chemoreceptors afferents in the NTS second order neurons.

    Science.gov (United States)

    Accorsi-Mendonça, Daniela; Machado, Benedito H

    2013-04-01

    Second order neurons in the nucleus tractus solitarius (NTS) process and integrate the afferent information from arterial baroreceptors with high fidelity and precise timing synaptic transmission. Since 2nd-order NTS neurons receiving baroreceptors inputs are relatively well characterized, their electrophysiological profile has been accepted as a general characteristic for all 2nd-order NTS neurons involved with the processing of different sensorial inputs. On the other hand, the synaptic properties of other afferent systems in NTS, such as the peripheral chemoreceptors, are not yet well understood. In this context, in previous studies we demonstrated that in response to repetitive afferents stimulation, the chemoreceptors 2nd-order NTS neurons also presented high fidelity of synaptic transmission, but with a large variability in the latency of evoked responses. This finding is different in relation to the precise timing transmission for baroreceptor 2nd-order NTS neurons, which was accepted as a general characteristic profile for all 2nd order neurons in the NTS. In this brief review we discuss this new concept as an index of complexity of the sensorial inputs to NTS with focus on the synaptic processing of baro- and chemoreceptor afferents.

  18. The structural biology of the FGF19 subfamily.

    Science.gov (United States)

    Beenken, Andrew; Mohammadi, Moosa

    2012-01-01

    The ability of the Fibroblast Growth Factor (FGF) 19 subfamily to signal in an endocrine fashion sets this subfamily apart from the remaining five FGF subfamilies known for their paracrine functions during embryonic development. Compared to the members of paracrine FGF subfamiles, the three members of the FGF19 subfamily, namely FGF19, FGF21 and FGF23, have poor affinity for heparan sulfate (HS) and therefore can diffuse freely in the HS-rich extracellular matrix to enter into the bloodstream. In further contrast to paracrine FGFs, FGF19 subfamily members have unusually poor affinity for their cognate FGF receptors (FGFRs) and therefore cannot bind and activate them in a solely HS-dependent fashion. As a result, the FGF19 subfamily requires α/βklotho coreceptor proteins in order to bind, dimerize and activate their cognate FGFRs. This klotho-dependency also determines the tissue specificity of endocrine FGFs. Recent structural and biochemical studies have begun to shed light onto the molecular basis for the klotho-dependent endocrine mode of action of the FGF19 subfamily. Crystal structures of FGF19 and FGF23 show that the topology of the HS binding site (HBS) of FGF19 subfamily members deviates drastically from the common topology adopted by the paracrine FGFs. The distinct topologies of the HBS of FGF19 and FGF23 prevent HS from direct hydrogen bonding with the backbone atoms of the HBS of these ligands and accordingly decrease the HS binding affinity of this subfamily. Recent biochemical data reveal that the ?klotho ectodomain binds avidly to the ectodomain of FGFR1c, the main cognate FGFR of FGF23, creating a de novo high affinity binding site for the C-terminal tail of FGF23. The isolated FGF23 C-terminus can be used to effectively inhibit the formation of the FGF23-FGFR1c-αklotho complex and alleviate hypophosphatemia in renal phosphate disorders due to elevated levels of FGF23.

  19. Identification of a Chemoreceptor in Pseudomonas aeruginosa That Specifically Mediates Chemotaxis Toward α-Ketoglutarate

    Science.gov (United States)

    Martín-Mora, David; Ortega, Alvaro; Reyes-Darias, José A.; García, Vanina; López-Farfán, Diana; Matilla, Miguel A.; Krell, Tino

    2016-01-01

    Pseudomonas aeruginosa is an ubiquitous pathogen able to infect humans, animals, and plants. Chemotaxis was found to be associated with the virulence of this and other pathogens. Although established as a model for chemotaxis research, the majority of the 26 P. aeruginosa chemoreceptors remain functionally un-annotated. We report here the identification of PA5072 (named McpK) as chemoreceptor for α-ketoglutarate (αKG). High-throughput thermal shift assays and isothermal titration calorimetry studies (ITC) of the recombinant McpK ligand binding domain (LBD) showed that it recognizes exclusively α-ketoglutarate. The ITC analysis indicated that the ligand bound with positive cooperativity (Kd1 = 301 μM, Kd2 = 81 μM). McpK is predicted to possess a helical bimodular (HBM) type of LBD and this and other studies suggest that this domain type may be associated with the recognition of organic acids. Analytical ultracentrifugation (AUC) studies revealed that McpK-LBD is present in monomer-dimer equilibrium. Alpha-KG binding stabilized the dimer and dimer self-dissociation constants of 55 μM and 5.9 μM were derived for ligand-free and αKG-bound forms of McpK-LBD, respectively. Ligand-induced LBD dimer stabilization has been observed for other HBM domain containing receptors and may correspond to a general mechanism of this protein family. Quantitative capillary chemotaxis assays demonstrated that P. aeruginosa showed chemotaxis to a broad range of αKG concentrations with maximal responses at 500 μM. Deletion of the mcpK gene reduced chemotaxis over the entire concentration range to close to background levels and wild type like chemotaxis was recovered following complementation. Real-time PCR studies indicated that the presence of αKG does not modulate mcpK expression. Since αKG is present in plant root exudates it was investigated whether the deletion of mcpK altered maize root colonization. However, no significant changes with respect to the wild type strain

  20. Identification of a Chemoreceptor in Pseudomonas aeruginosa that specifically mediates Chemotaxis towards alpha-Ketoglutarate

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    David Martin-Mora

    2016-11-01

    Full Text Available Pseudomonas aeruginosa is an ubiquitous pathogen able to infect humans, animals and plants. Chemotaxis was found to be associated with the virulence of this and other pathogens. Although established as a model for chemotaxis research, the majority of the 26 P. aeruginosa chemoreceptors remain functionally un-annotated. We report here the identification of PA5072 (named McpK as chemoreceptor for -ketoglutarate (KG. High-throughput thermal shift assays and isothermal titration calorimetry studies (ITC of the recombinant McpK ligand binding domain (LBD show that it recognizes exclusively -ketoglutarate. The ITC analysis indicated that the ligand bound with positive cooperativity (Kd1=301 µM, Kd2=81 µM. McpK is predicted to possess a helical bimodular (HBM type of LBD and this and other studies suggest that this domain type may be associated with the recognition of organic acids. Analytical ultracentrifugation (AUC studies revealed that McpK-LBD is present in a monomer-dimer equilibrium. Alpha-KG binding stabilized the dimer and dimer self-dissociation constants of 55 µM and 5.9 µM were derived for ligand-free and KG-bound forms of McpK-LBD, respectively. Ligand-induced LBD dimer stabilization has been observed for other HBM domain containing receptors and may correspond to a general mechanism of this protein family. Quantitative capillary chemotaxis assays demonstrated that P. aeruginosa showed chemotaxis to a broad range of KG concentrations with maximal responses at 500 µM. Deletion of the mcpK gene reduced chemotaxis over the entire concentration range to close to background levels and wild type like chemotaxis was recovered following complementation. Real-time PCR studies indicated that the presence of KG does not modulate mcpK expression. Since KG is present in plant root exudates it was investigated whether the deletion of mcpK altered maize root colonization. However, no significant changes with respect to the wild

  1. SOS System Induction Inhibits the Assembly of Chemoreceptor Signaling Clusters in Salmonella enterica.

    Science.gov (United States)

    Irazoki, Oihane; Mayola, Albert; Campoy, Susana; Barbé, Jordi

    2016-01-01

    Swarming, a flagellar-driven multicellular form of motility, is associated with bacterial virulence and increased antibiotic resistance. In this work we demonstrate that activation of the SOS response reversibly inhibits swarming motility by preventing the assembly of chemoreceptor-signaling polar arrays. We also show that an increase in the concentration of the RecA protein, generated by SOS system activation, rather than another function of this genetic network impairs chemoreceptor polar cluster formation. Our data provide evidence that the molecular balance between RecA and CheW proteins is crucial to allow polar cluster formation in Salmonella enterica cells. Thus, activation of the SOS response by the presence of a DNA-injuring compound increases the RecA concentration, thereby disturbing the equilibrium between RecA and CheW and resulting in the cessation of swarming. Nevertheless, when the DNA-damage decreases and the SOS response is no longer activated, basal RecA levels and thus polar cluster assembly are reestablished. These results clearly show that bacterial populations moving over surfaces make use of specific mechanisms to avoid contact with DNA-damaging compounds.

  2. SOS System Induction Inhibits the Assembly of Chemoreceptor Signaling Clusters in Salmonella enterica.

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    Oihane Irazoki

    Full Text Available Swarming, a flagellar-driven multicellular form of motility, is associated with bacterial virulence and increased antibiotic resistance. In this work we demonstrate that activation of the SOS response reversibly inhibits swarming motility by preventing the assembly of chemoreceptor-signaling polar arrays. We also show that an increase in the concentration of the RecA protein, generated by SOS system activation, rather than another function of this genetic network impairs chemoreceptor polar cluster formation. Our data provide evidence that the molecular balance between RecA and CheW proteins is crucial to allow polar cluster formation in Salmonella enterica cells. Thus, activation of the SOS response by the presence of a DNA-injuring compound increases the RecA concentration, thereby disturbing the equilibrium between RecA and CheW and resulting in the cessation of swarming. Nevertheless, when the DNA-damage decreases and the SOS response is no longer activated, basal RecA levels and thus polar cluster assembly are reestablished. These results clearly show that bacterial populations moving over surfaces make use of specific mechanisms to avoid contact with DNA-damaging compounds.

  3. Same same but different. Different trigeminal chemoreceptors share the same central pathway.

    Directory of Open Access Journals (Sweden)

    Kathrin Kollndorfer

    Full Text Available Intranasal trigeminal sensations are important in everyday life of human beings, as they play a governing role in protecting the airways from harm. Trigeminal sensations arise from the binding of a ligand to various sub-types of transient receptor potential (TRP channels located on mucosal branches of the trigeminal nerve. Which underlying neural networks are involved in the processing of various trigeminal inputs is still unknown. To target this unresolved question fourteen healthy human subjects were investigated by completing three functional magnetic resonance imaging (fMRI scanning sessions during which three trigeminal substances, activating varying sub-types of chemoreceptors and evoking different sensations in the nose were presented: CO2, menthol and cinnamaldehyde. We identified similar functional networks responding to all stimuli: an olfactory network, a somatosensory network and an integrative network. The processing pathway of all three stimulants was represented by the same functional networks, although CO2 evokes painful but virtually odorless sensations, and the two other stimulants, menthol and cinnamaldehyde are perceived as mostly non painful with a clear olfactory percept. Therefore, our results suggest a common central processing pathway for trigeminal information regardless of the trigeminal chemoreceptor and sensation type.

  4. Organization and evolution of two SIDER retroposon subfamilies and their impact on the Leishmania genome

    Directory of Open Access Journals (Sweden)

    Bringaud Frédéric

    2009-05-01

    major differences. The SIDER1 subfamily is more heterogeneous and shows an evolutionary link with vestigial DIRE retroposons as previously observed for the ingi/RIME and L1Tc/NARTc couples identified in the T. brucei and T. cruzi genomes, whereas no identified DIREs are related to SIDER2 sequences. Although SIDER1s and SIDER2s display equivalent genomic distribution globally, the varying degrees of sequence conservation, preferential genomic disposition, and differential association to orthologous genes allude to an intricate web of SIDER assimilation in these parasitic organisms.

  5. Minimal subfamilies and the probabilistic interpretation for modulus on graphs

    CERN Document Server

    Albin, Nathan

    2016-01-01

    The notion of $p$-modulus of a family of objects on a graph is a measure of the richness of such families. We develop the notion of minimal subfamilies using the method of Lagrangian duality for $p$-modulus. We show that minimal subfamilies have at most $|E|$ elements and that these elements carry a weight related to their "importance" in relation to the corresponding $p$-modulus problem. When $p=2$, this measure of importance is in fact a probability measure and modulus can be thought as trying to minimize the expected overlap in the family.

  6. Characterisation of a multi-ligand binding chemoreceptor CcmL (Tlp3 of Campylobacter jejuni.

    Directory of Open Access Journals (Sweden)

    Hossinur Rahman

    2014-01-01

    Full Text Available Campylobacter jejuni is the leading cause of human gastroenteritis worldwide with over 500 million cases annually. Chemotaxis and motility have been identified as important virulence factors associated with C. jejuni colonisation. Group A transducer-like proteins (Tlps are responsible for sensing the external environment for bacterial movement to or away from a chemical gradient or stimulus. In this study, we have demonstrated Cj1564 (Tlp3 to be a multi-ligand binding chemoreceptor and report direct evidence supporting the involvement of Cj1564 (Tlp3 in the chemotaxis signalling pathway via small molecule arrays, surface plasmon and nuclear magnetic resonance (SPR and NMR as well as chemotaxis assays of wild type and isogenic mutant strains. A modified nutrient depleted chemotaxis assay was further used to determine positive or negative chemotaxis with specific ligands. Here we demonstrate the ability of Cj1564 to interact with the chemoattractants isoleucine, purine, malic acid and fumaric acid and chemorepellents lysine, glucosamine, succinic acid, arginine and thiamine. An isogenic mutant of cj1564 was shown to have altered phenotypic characteristics of C. jejuni, including loss of curvature in bacterial cell shape, reduced chemotactic motility and an increase in both autoagglutination and biofilm formation. We demonstrate Cj1564 to have a role in invasion as in in vitro assays the tlp3 isogenic mutant has a reduced ability to adhere and invade a cultured epithelial cell line; interestingly however, colonisation ability of avian caeca appears to be unaltered. Additionally, protein-protein interaction studies revealed signal transduction initiation through the scaffolding proteins CheV and CheW in the chemotaxis sensory pathway. This is the first report characterising Cj1564 as a multi-ligand receptor for C. jejuni, we therefore, propose to name this receptor CcmL, Campylobacter chemoreceptor for multiple ligands. In conclusion, this study

  7. Chemotransduction in the Carotid Body: K+ Current Modulated by Po2 in Type I Chemoreceptor Cells

    Science.gov (United States)

    Lopez-Barneo, Jose; Lopez-Lopez, Jose R.; Urena, Juan; Gonzalez, Constancio

    1988-07-01

    The ionic currents of carotid body type I cells and their possible involvement in the detection of oxygen tension (Po2) in arterial blood are unknown. The electrical properties of these cells were studied with the whole-cell patch clamp technique, and the hypothesis that ionic conductances can be altered by changes in Po2 was tested. The results show that type I cells have voltage-dependent sodium, calcium, and potassium channels. Sodium and calcium currents were unaffected by a decrease in Po2 from 150 to 10 millimeters of mercury, whereas, with the same experimental protocol, potassium currents were reversibly reduced by 25 to 50 percent. The effect of hypoxia was independent of internal adenosine triphosphate and calcium. Thus, ionic conductances, and particularly the O2-sensitive potassium current, play a key role in the transduction mechanism of arterial chemoreceptors.

  8. A direct-sensing galactose chemoreceptor recently evolved in invasive strains of Campylobacter jejuni

    Science.gov (United States)

    Day, Christopher J.; King, Rebecca M.; Shewell, Lucy K.; Tram, Greg; Najnin, Tahria; Hartley-Tassell, Lauren E.; Wilson, Jennifer C.; Fleetwood, Aaron D.; Zhulin, Igor B.; Korolik, Victoria

    2016-10-01

    A rare chemotaxis receptor, Tlp11, has been previously identified in invasive strains of Campylobacter jejuni, the most prevalent cause of bacterial gastroenteritis worldwide. Here we use glycan and small-molecule arrays, as well as surface plasmon resonance, to show that Tlp11 specifically interacts with galactose. Tlp11 is required for the chemotactic response of C. jejuni to galactose, as shown using wild type, allelic inactivation and addition mutants. The inactivated mutant displays reduced virulence in vivo, in a model of chicken colonization. The Tlp11 sensory domain represents the first known sugar-binding dCache_1 domain, which is the most abundant family of extracellular sensors in bacteria. The Tlp11 signalling domain interacts with the chemotaxis scaffolding proteins CheV and CheW, and comparative genomic analysis indicates a likely recent evolutionary origin for Tlp11. We propose to rename Tlp11 as CcrG, Campylobacter ChemoReceptor for Galactose.

  9. Identification and Characterization of the Populus AREB/ABF Subfamily

    Institute of Scientific and Technical Information of China (English)

    Lexiang Ji; Jia Wang; Meixia Ye; Ying Li; Bin Guo; Zhong Chen; Hao Li; Xinmin An

    2013-01-01

    Abscisic acid (ABA) is a major plant hormone that plays an important role in responses to abiotic stresses.The ABA-responsive element binding proteinlABRE-binding factor (AREB/ABF) gene subfamily contains crucial transcription factors in the ABA-mediated signaling pathway.In this study,a total of 14 putative AREB/ABF members were identified in the Populus trichocarpa Torr.& Gray.genome using five AREB/ABF amino acid sequences from Arabidopsis thaliana L.as probes.The 14 putative Populus subfamily members showed high protein similarities,especially in the basic leucine zipper (bZlP) domain region.A neighbor-joining analysis combined with gene structure data revealed homology among the 14 genes.The expression patterns of the Populus AREB/ABF subfamily suggested that the most abundant transcripts of 11 genes occurred in leaf tissues,while two genes were most transcribed in root tissues.Significantly,eight Populus AREB/ABF gene members were upregulated after treatment with 100 μM exogenous ABA,while the other six members were downregulated.We identified the expression profiles of the subfamily members in Populus tissues and elucidated different response patterns of Populus AREB/ABF members to ABA stress.This study provided insight into the roles of Populus AREB/ABF homologues in plant response to abiotic stresses.

  10. Vaillantellinae, A New Subfamily Of Cobitidae (Pisces, Cypriniformes)

    NARCIS (Netherlands)

    Nalbant, T.T.; Banarescu, P.M.

    1977-01-01

    INTRODUCTION It is generally accepted that the Eurasian freshwater fish family Cobitidae includes three main divisions, usually considered as subfamilies: Cobitinae, Botiinae and Noemacheilinae (Berg, 1940; Ramaswami, 1953; Nalbant, 1963). The two first named, in which the lateral ethmoids are movab

  11. First molecular phylogeny of the subfamily Polycerinae (Mollusca, Nudibranchia, Polyceridae)

    Science.gov (United States)

    Palomar, Gemma; Pola, Marta; Garcia-Vazquez, Eva

    2014-03-01

    The subfamily Polycerinae includes four genera with around 46 species described to date. This subfamily is characterized by a limaciform body, which may have simple tentacular processes on the margin of the oral veil. Phylogenetic relationships between the genera of the subfamily Polycerinae (Polyceridae) have not yet been studied, and therefore, the only available information is based on morphological descriptions. The present study reports the first phylogenetic analysis of Polycerinae based on the mitochondrial genes cytochrome oxidase subunit I and the large ribosomal subunit (16S rRNA) using maximum likelihood and Bayesian methods. Our results showed that Polycerinae is monophyletic, but the relationships within the subfamily as well as within Polycera remain unresolved. A key finding of this study is that there are clearly two sympatric species of Polycera present in South Africa: Polycera capensis Quoy and Gaimard, 1824 also found in Australia and an undescribed Polycera sp. On the other hand, the studied specimens of the genus Gymnodoris were clustered within Polycerinae, reopening the problem of the systematic position of this genus. Additional genes and species of Polycerinae and Gymnodoris would provide more information and probably fully resolve this situation.

  12. Peripheral chemoreceptors tune inspiratory drive via tonic expiratory neuron hubs in the medullary ventral respiratory column network.

    Science.gov (United States)

    Segers, L S; Nuding, S C; Ott, M M; Dean, J B; Bolser, D C; O'Connor, R; Morris, K F; Lindsey, B G

    2015-01-01

    Models of brain stem ventral respiratory column (VRC) circuits typically emphasize populations of neurons, each active during a particular phase of the respiratory cycle. We have proposed that "tonic" pericolumnar expiratory (t-E) neurons tune breathing during baroreceptor-evoked reductions and central chemoreceptor-evoked enhancements of inspiratory (I) drive. The aims of this study were to further characterize the coordinated activity of t-E neurons and test the hypothesis that peripheral chemoreceptors also modulate drive via inhibition of t-E neurons and disinhibition of their inspiratory neuron targets. Spike trains of 828 VRC neurons were acquired by multielectrode arrays along with phrenic nerve signals from 22 decerebrate, vagotomized, neuromuscularly blocked, artificially ventilated adult cats. Forty-eight of 191 t-E neurons fired synchronously with another t-E neuron as indicated by cross-correlogram central peaks; 32 of the 39 synchronous pairs were elements of groups with mutual pairwise correlations. Gravitational clustering identified fluctuations in t-E neuron synchrony. A network model supported the prediction that inhibitory populations with spike synchrony reduce target neuron firing probabilities, resulting in offset or central correlogram troughs. In five animals, stimulation of carotid chemoreceptors evoked changes in the firing rates of 179 of 240 neurons. Thirty-two neuron pairs had correlogram troughs consistent with convergent and divergent t-E inhibition of I cells and disinhibitory enhancement of drive. Four of 10 t-E neurons that responded to sequential stimulation of peripheral and central chemoreceptors triggered 25 cross-correlograms with offset features. The results support the hypothesis that multiple afferent systems dynamically tune inspiratory drive in part via coordinated t-E neurons.

  13. Reductions in carotid chemoreceptor activity with low-dose dopamine improves baroreflex control of heart rate during hypoxia in humans.

    Science.gov (United States)

    Mozer, Michael T; Holbein, Walter W; Joyner, Michael J; Curry, Timothy B; Limberg, Jacqueline K

    2016-07-01

    The purpose of the present investigation was to examine the contribution of the carotid body chemoreceptors to changes in baroreflex control of heart rate with exposure to hypoxia. We hypothesized spontaneous cardiac baroreflex sensitivity (scBRS) would be reduced with hypoxia and this effect would be blunted when carotid chemoreceptor activity was reduced with low-dose dopamine. Fifteen healthy adults (11 M/4 F) completed two visits randomized to intravenous dopamine or placebo (saline). On each visit, subjects were exposed to 5-min normoxia (~99% SpO2), followed by 5-min hypoxia (~84% SpO2). Blood pressure (intra-arterial catheter) and heart rate (ECG) were measured continuously and scBRS was assessed by spectrum and sequence methodologies. scBRS was reduced with hypoxia (P dopamine (P dopamine (P dopamine did not attenuate the decrease in baroreflex sensitivity to falling pressures (scBRS "down-down"; P > 0.05). Present findings are consistent with a reduction in scBRS with systemic hypoxia. Furthermore, we show this effect is partially mediated by the carotid body chemoreceptors, given the fall in scBRS is attenuated when activity of the chemoreceptors is reduced with low-dose dopamine. However, the improvement in scBRS with dopamine appears to be specific to rising blood pressures. These results may have important implications for impairments in baroreflex function common in disease states of acute and/or chronic hypoxemia, as well as the experimental use of dopamine to assess such changes.

  14. Regulation of caste differentiation in the honey bee (Apis mellifera L.)

    NARCIS (Netherlands)

    Goewie, E.A.

    1978-01-01

    The nutritional environment of honey-bee larvae affects the juvenile hormone (JH) titre of larval haemolymph and tissues. In this investigation the mechanism for the regulation of caste differentiation has been studied.Chemo- and mechanoreceptors are found on larval mouthparts. Chemoreceptors on max

  15. Comamonas testosteroni uses a chemoreceptor for tricarboxylic acid cycle intermediates to trigger chemotactic responses towards aromatic compounds.

    Science.gov (United States)

    Ni, Bin; Huang, Zhou; Fan, Zheng; Jiang, Cheng-Ying; Liu, Shuang-Jiang

    2013-11-01

    Bacterial chemotaxis towards aromatic compounds has been frequently observed; however, knowledge of how bacteria sense aromatic compounds is limited. Comamonas testosteroni CNB-1 is able to grow on a range of aromatic compounds. This study investigated the chemotactic responses of CNB-1 to 10 aromatic compounds. We constructed a chemoreceptor-free, non-chemotactic mutant, CNB-1Δ20, by disruption of all 19 putative methyl-accepting chemotaxis proteins (MCPs) and the atypical chemoreceptor in strain CNB-1. Individual complementation revealed that a putative MCP (tagged MCP2201) was involved in triggering chemotaxis towards all 10 aromatic compounds. The recombinant sensory domain of MCP2201 did not bind to 3- or 4-hydroxybenzoate, protocatechuate, catechol, benzoate, vanillate and gentisate, but bound oxaloacetate, citrate, cis-aconitate, isocitrate, α-ketoglutarate, succinate, fumarate and malate. The mutant CNB-1ΔpmdF that lost the ability to metabolize 4-hydroxybenzoate and protocatechuate also lost its chemotactic response to these compounds, suggesting that taxis towards aromatic compounds is metabolism-dependent. Based on the ligand profile, we proposed that MCP2201 triggers taxis towards aromatic compounds by sensing TCA cycle intermediates. Our hypothesis was further supported by the finding that introduction of the previously characterized pseudomonad chemoreceptor (McpS) for TCA cycle intermediates into CNB-1Δ20 likewise triggered chemotaxis towards aromatic compounds.

  16. Nuclear phylogenomics of the palm subfamily Arecoideae (Arecaceae).

    Science.gov (United States)

    Comer, Jason R; Zomlefer, Wendy B; Barrett, Craig F; Stevenson, Dennis Wm; Heyduk, Karolina; Leebens-Mack, James H

    2016-04-01

    Palms (Arecaceae) include economically important species such as coconut, date palm, and oil palm. Resolution of the palm phylogeny has been problematic due to rapid diversification and slow rates of molecular evolution. The focus of this study is on relationships of the 14 tribes of subfamily Arecoideae and their inferred ancestral areas. A targeted sequencing approach was used to generate a data set of 168 single/low copy nuclear genes for 34 species representing the Arecoideae tribes and the other palm subfamilies. Species trees from the concatenated and coalescent based analyses recovered largely congruent topologies. Three major tribal clades were recovered: the POS clade (Podococceae, Oranieae, Sclerospermeae), the RRC clade (Roystoneeae, Reinhardtieae, Cocoseae), and the core arecoid clade (Areceae, Euterpeae, Geonomateae, Leopoldinieae, Manicarieae, Pelagodoxeae). Leopoldinieae was sister to the rest of the core arecoids (Geonomateae, Manicarieae+Pelagodoxeae, and Areceae+Euterpeae). The nuclear phylogeny supported a North American origin for subfamily Arecoideae, with most tribal progenitors diversifying within the Americas. The POS clade may have dispersed from the Americas into Africa, with tribe Oranieae subsequently spreading into the Indo-Pacific. Two independent dispersals into the Indo-Pacific were inferred for two tribes within the core arecoids (tribes Areceae and Pelagodoxeae).

  17. Cytogenetics and genome evolution in the subfamily Triatominae (Hemiptera, Reduviidae).

    Science.gov (United States)

    Panzera, F; Pérez, R; Panzera, Y; Ferrandis, I; Ferreiro, M J; Calleros, L

    2010-01-01

    The subfamily Triatominae (Hemiptera, Reduviidae), vectors of Chagas disease, includes over 140 species. Karyotypic information is currently available for 80 of these species. This paper summarizes the chromosomal variability of the subfamily and how it may reveal aspects of genome evolution in this group. The Triatominae present a highly conserved chromosome number. All species, except 3, present 20 autosomes. The differences in chromosome number are mainly caused by variation in the number of sex chromosomes, due to the existence of 3 sex systems in males (XY, X(1)X(2)Y and X(1)X(2)X(3)Y). However, inter- and intraspecific differences in the position, quantity and meiotic behavior of constitutive heterochromatin, in the total genome size, and in the location of ribosomal 45S rRNA clusters, have revealed considerable cytogenetic variability within the subfamily. This cytogenetic diversity offers the opportunity to perform cytotaxonomic and phylogenetic studies, as well as structural, evolutionary, and functional analyses of the genome. The imminent availability of the complete genome of Rhodnius prolixus also opens new perspectives for understanding the evolution and genome expression of triatomines. The application of fluorescence in situ hybridization for the mapping of genes and sequences, as well as comparative analyses of genome homology by comparative genomic hybridization will be useful tools for understanding the genomic changes in relation to evolutionary processes such as speciation and adaptation to different environments.

  18. Nasal mites of the subfamily Speleognathinae (Ereynetidae) from birds in Texas.

    Science.gov (United States)

    Pence, D B; Casto, S D

    1976-06-01

    Nasal mites of the subfamily Speleognathinae were recovered from several species of birds in Texas. New host records include Ophthalmophagus striatus (Crossley) 1952 from Columbigallina passerina, Boydaia clarki Fain 1963 from Callipepla squamata, Boydaia falconis Fain 1956 from Falco sparverius, and Boydaia tyrannus Ford 1959 from Myiarchus cinerascens. Also recovered was Astrida coccyzae Pence 1972 from Coccyzus americanus. Boydaia pheucticola sp. n. from Pheucticus melanocephalus is described. It differs from similar species in the adult female by having the coxal setae formula 2-1-2-0, sensillae clavate but not globose or subglobose, and interior seta on coxa I reduced in size but not vestigial. The larva is differentiated by the modified legs II with one long recurved hooklike claw and a shorter curved claw.

  19. The HRASLS (PLA/AT) subfamily of enzymes.

    Science.gov (United States)

    Mardian, Emily B; Bradley, Ryan M; Duncan, Robin E

    2015-10-26

    The H-RAS-like suppressor (HRASLS) subfamily consists of five enzymes (1-5) in humans and three (1, 3, and 5) in mice and rats that share sequence homology with lecithin:retinol acyltransferase (LRAT). All HRASLS family members possess in vitro phospholipid metabolizing abilities including phospholipase A1/2 (PLA1/2) activities and O-acyltransferase activities for the remodeling of glycerophospholipid acyl chains, as well as N-acyltransferase activities for the production of N-acylphosphatidylethanolamines. The in vivo biological activities of the HRASLS enzymes have not yet been fully investigated. Research to date indicates involvement of this subfamily in a wide array of biological processes and, as a consequence, these five enzymes have undergone extensive rediscovery and renaming within different fields of research. This review briefly describes the discovery of each of the HRASLS enzymes and their role in cancer, and discusses the biochemical function of each enzyme, as well as the biological role, if known. Gaps in current understanding are highlighted and suggestions for future research directions are discussed.

  20. Revision of the monogenean subfamily Neothoracocotylinae Lebedev, 1969 (Polyopisthocotylea: Thoracocotylidae).

    Science.gov (United States)

    Hayward, C J; Rohde, K

    1999-11-01

    Members of the subfamily Neothoracocotylinae are gastrocotylinean monogeneans on the gills of scombrid fishes of the genera Scomberomorus and Acanthocybium, and reportedly of a coryphaenid fish belonging to the genus Coryphaena. We revise the diagnosis of the subfamily and its two genera and accept only two species as valid. Neothoracocotyle acanthocybii (Meserve, 1938) Hargis, 1956 is known from Acanthocybium solandri throughout the Pacific Ocean and in the western Atlantic. N. coryphaenae (Yamaguti, 1938) Hargis, 1956, known only from a single specimen and described from Coryphaena hippurus in Japan, is synonymised with N. acanthocybii. The sole member of Scomberocotyle, S. scomberomori (Koratha, 1955) Hargis, 1956, infects five species of Scomberomorus in the eastern Pacific Ocean and the western and castern Atlantic. We record this worm from several new hosts and/or localities, including S. sierra and S. concolor in the eastern Pacific (Mexico to Colombia), S. maculatus and S. cavalla in the western Atlantic (USA to Brazil), and S. tritor in the eastern Atlantic (Sierra Leone to Nigeria).

  1. Functional suppression of HAMP domain signaling defects in the E. coli serine chemoreceptor.

    Science.gov (United States)

    Lai, Run-Zhi; Parkinson, John S

    2014-10-23

    HAMP domains play key signaling roles in many bacterial receptor proteins. The four-helix HAMP bundle of the homodimeric Escherichia coli serine chemoreceptor (Tsr) interacts with an adjoining four-helix sensory adaptation bundle to regulate the histidine autokinase CheA bound to the cytoplasmic tip of the Tsr molecule. The adaptation helices undergo reversible covalent modifications that tune the stimulus-responsive range of the receptor: unmodified E residues promote kinase-off output, and methylated E residues or Q replacements at modification sites promote kinase-on output. We used mutationally imposed adaptational modification states and cells with various combinations of the sensory adaptation enzymes, CheR and CheB, to characterize the signaling properties of mutant Tsr receptors that had amino acid replacements in packing layer 3 of the HAMP bundle and followed in vivo CheA activity with an assay based on Förster resonance energy transfer. We found that an alanine or a serine replacement at HAMP residue I229 effectively locked Tsr output in a kinase-on state, abrogating chemotactic responses. A second amino acid replacement in the same HAMP packing layer alleviated the I229A and I229S signaling defects. Receptors with the suppressor changes alone mediated chemotaxis in adaptation-proficient cells but exhibited altered sensitivity to serine stimuli. Two of the suppressors (S255E and S255A) shifted Tsr output toward the kinase-off state, but two others (S255G and L256F) shifted output toward a kinase-on state. The alleviation of locked-on defects by on-shifted suppressors implies that Tsr-HAMP has several conformationally distinct kinase-active output states and that HAMP signaling might involve dynamic shifts over a range of bundle conformations.

  2. Subfamily logos: visualization of sequence deviations at alignment positions with high information content

    Directory of Open Access Journals (Sweden)

    Beitz Eric

    2006-06-01

    Full Text Available Abstract Background Recognition of relevant sequence deviations can be valuable for elucidating functional differences between protein subfamilies. Interesting residues at highly conserved positions can then be mutated and experimentally analyzed. However, identification of such sites is tedious because automated approaches are scarce. Results Subfamily logos visualize subfamily-specific sequence deviations. The display is similar to classical sequence logos but extends into the negative range. Positive, upright characters correspond to residues which are characteristic for the subfamily, negative, upside-down characters to residues typical for the remaining sequences. The symbol height is adjusted to the information content of the alignment position. Residues which are conserved throughout do not appear. Conclusion Subfamily logos provide an intuitive display of relevant sequence deviations. The method has proven to be valid using a set of 135 aligned aquaporin sequences in which established subfamily-specific positions were readily identified by the algorithm.

  3. The Formation of the Polyploid Hybrids From Different Subfamily Fish Crossings and Its Evolutionary Significance

    OpenAIRE

    Liu, Shaojun; Qin, Qinbo; Xiao, Jun; Lu, Wenting; Shen, Jiamin; Li, Wei; Liu, Jifang; Duan, Wei; Zhang, Chun; Tao, De Min; Zhao, Rurong; Yan, Jinpeng; Liu, Yun

    2007-01-01

    This study provides genetic evidences at the chromosome, DNA content, DNA fragment and sequence, and morphological levels to support the successful establishment of the polyploid hybrids of red crucian carp × blunt snout bream, which belonged to a different subfamily of fish (Cyprininae subfamily and Cultrinae subfamily) in the catalog. We successfully obtained the sterile triploid hybrids and bisexual fertile tetraploid hybrids of red crucian carp (RCC) (♀) × blunt snout bream (BSB) (♂) as w...

  4. The Caenorhabditis elegans parvulin gene subfamily and their expression under cold or heat stress along with the fkb subfamily.

    Science.gov (United States)

    Fasseas, Michael K; Dimou, Maria; Katinakis, Panagiotis

    2012-07-06

    Parvulins and FKBPs are members of the peptidyl-prolyl cis/trans isomerases (PPIase) enzyme family whose role is to catalyze the interconversion between the cis trans forms of a peptide bond preceding internal proline residues in a polypeptide substrate. Members of the parvulin subfamily have been found to be involved in a variety of diseases, including Alzheimer's disease and cancer and are also considered possible antiparasitic targets. Genes Y110A2AL.13 (pin-1) and Y48C3A.16 (pin-4) were found in the worm's genome, possibly encoding parvulins. One is homologous to human and fly PIN1 whereas the other is homologous to human and fly PIN4. Both were expressed in Escherichia coli, purified and found to have in vitro PPIase activity. Expression levels of both genes, as well as the fkb genes (that encode FK506-binding proteins) were measured during development and under cold or heat stress conditions. The results revealed a potential role for these genes under temperature-related stress. RNAi silencing was performed for wild type and mutant strain worms under normal and cold or heat stress conditions. A reduced lifespan was observed when pin-4 dsRNA was fed to the fkb-5 deficient worms. Our work presents a first attempt to characterize the Caenorhabditis elegans parvulins and may present an interesting starting point for further experimentation concerning their role, along with the FKBP subfamily, in nematode physiology and their possible use as antiparasitic targets.

  5. Moving out: from sterol transport to drug resistance - the ABCG subfamily of efflux pumps.

    Science.gov (United States)

    Moitra, Karobi; Silverton, Latoya; Limpert, Katy; Im, Kate; Dean, Michael

    2011-01-01

    The ATP binding cassette (ABC) proteins are typically ATP-driven transmembrane pumps that have been evolutionarily conserved from bacteria to humans. In humans these transporters are subdivided into seven subfamilies, ranging from A to G. The ABCG subfamily of transporters is the primary focus of this review. This subfamily of proteins has been conserved throughout evolution and plays a central role in several cellular processes, such as sterol homeostasis and multidrug resistance. Functional polymorphisms/mutations in some of these G-subfamily transporters have clinical consequences in humans.

  6. Two new nematode species of the subfamily Brittonematinae (Dorylaimida: Actinolaimidae

    Directory of Open Access Journals (Sweden)

    Andrássy, I.

    2010-10-01

    Full Text Available Abstract. Two new species of actinolaimoid nematodes of the subfamily Brittonematinae are described and illustrated.Actinca marisae sp. n. from Brazil is characterized by the long (on average 2.92 mm and slender body, 30–32 distinct longitudinalridges on cuticle, narrow head, slender odontostyle, onchial tips facing each other, cylindrus occupying somewhat lessthan one-half of pharynx, broad vulval lips, and by medum long tail. Afractinca eburnea sp. n. from Côte d’Ivoire can bedistinguished by a relatively long body (on average 1.88 mm, thin cuticle provided with 14 longitudinal ridges, cap-like offsetlabial ring, very slender odontostyle, long prerectum, vulva sunk in body contour, and by the elongate-conoid female tail. Mainmorphological structures of Actinca and Afractinca species are summarized. Some comments on further brittonematine speciesare added.

  7. Evolution of C2H2-zinc finger genes and subfamilies in mammals: Species-specific duplication and loss of clusters, genes and effector domains

    Directory of Open Access Journals (Sweden)

    Aubry Muriel

    2008-06-01

    Full Text Available Abstract Background C2H2 zinc finger genes (C2H2-ZNF constitute the largest class of transcription factors in humans and one of the largest gene families in mammals. Often arranged in clusters in the genome, these genes are thought to have undergone a massive expansion in vertebrates, primarily by tandem duplication. However, this view is based on limited datasets restricted to a single chromosome or a specific subset of genes belonging to the large KRAB domain-containing C2H2-ZNF subfamily. Results Here, we present the first comprehensive study of the evolution of the C2H2-ZNF family in mammals. We assembled the complete repertoire of human C2H2-ZNF genes (718 in total, about 70% of which are organized into 81 clusters across all chromosomes. Based on an analysis of their N-terminal effector domains, we identified two new C2H2-ZNF subfamilies encoding genes with a SET or a HOMEO domain. We searched for the syntenic counterparts of the human clusters in other mammals for which complete gene data are available: chimpanzee, mouse, rat and dog. Cross-species comparisons show a large variation in the numbers of C2H2-ZNF genes within homologous mammalian clusters, suggesting differential patterns of evolution. Phylogenetic analysis of selected clusters reveals that the disparity in C2H2-ZNF gene repertoires across mammals not only originates from differential gene duplication but also from gene loss. Further, we discovered variations among orthologs in the number of zinc finger motifs and association of the effector domains, the latter often undergoing sequence degeneration. Combined with phylogenetic studies, physical maps and an analysis of the exon-intron organization of genes from the SCAN and KRAB domains-containing subfamilies, this result suggests that the SCAN subfamily emerged first, followed by the SCAN-KRAB and finally by the KRAB subfamily. Conclusion Our results are in agreement with the "birth and death hypothesis" for the evolution of

  8. Rho participates in chemoreceptor-induced changes in morphology to hair bundle mechanoreceptors of the sea anemone, Nematostella vectensis.

    Science.gov (United States)

    Allaire, Kathryn M; Watson, Glen M

    2013-06-01

    Adjustable hair bundle mechanoreceptors located on anemone tentacles detect movements of nearby, swimming prey. The hair bundles are formed by numerous actin-based stereocilia that converge onto a single, central kinocilium. Interestingly, morphological and functional changes to the hair bundles are induced by activating chemoreceptors that bind prey-derived N-acetylated sugars and proline, respectively. Morphological changes to the hair bundles involve alterations to the actin cytoskeleton of stereocilia. A pharmacological activation of Rho induces hair bundles to elongate to lengths comparable to those normally induced by exposure to N-acetylneuraminic acid (NANA) and prevents shortening of hair bundles normally induced by proline. Rho inhibition prevents NANA-induced elongation, but does not prevent proline-induced shortening of hair bundles. Western blots feature a band similar in mass to that predicted for a Rho homolog in the genome of Nematostella. Immunocytochemistry localizes Rho in stereocilia of the hair bundle. Anemone hair bundles arise from multicellular complexes. Data from experiments using heptanol, a gap junction uncoupler, indicate that cell-cell communication is required in order for activated chemoreceptors to induce morphological changes to the hair bundles.

  9. On the correct name for some subfamilies of Mustelidae (Mammalia, Carnivora

    Directory of Open Access Journals (Sweden)

    Fabio Oliveira do Nascimento

    2014-01-01

    Full Text Available Mustelids (Mustelidae exhibit a wide morphological and ecological diversity, ranging from aquatic to semi arboreal and fossorial forms. It is the most diversity family in Carnivora, and this has promoted a great number of taxonomic arrangements for subfamilies, which can range from two to 15 depending on the author. The relatively recent use of molecular data has helped to elucidate the classification of mustelids, and eight subfamilies are currently recognized: Mustelinae, Galictinae, Helictidinae, Martinae, Melinae, Mellivorinae, Taxidiinae and Lutrinae. However, some of these subfamilies have nomenclatural problems, not receiving the oldest available name. The subfamily that includes martens (Martes, Charronia and Pekania, tayra (Eira and wolverine (Gulo has received the name of Martinae Wagner, 1841, but the oldest available name is Guloninae Gray, 1825. This problem also occurs for the subfamily that includes the grisons (Galictis, Patagonian weasel (Lyncodon, marbled polecat (Vormela and striped weasels (Ictonyx and Poecilogale, which are known as Grisoninae Pocock, 1921, but the correct name for this group is Ictonychinae, Pocock, 1921. The subfamily that includes ferret badgers (Melogale retains the name Helictidinae Gray, 1865, because its validity is not affected when the type-genus of the subfamily becomes a junior synonym of another genus. Furthermore, a list of the extant subfamilies of Mustelidae and their respective synonyms and included genera is provided.

  10. Historical legacies in the geographical diversity patterns of New World palm (Arecaceae) subfamilies

    DEFF Research Database (Denmark)

    Bjorholm, Stine; Svenning, Jens-Christian; Baker, William

    2006-01-01

    The extent to which species richness patterns of the major palm subfamilies in the Americas are controlled by lineage history was studied. Based on the fossil record, we suggest that the subfamily Coryphoideae has followed a boreotropical dispersal route into Central and South America, whereas ca...

  11. Phantoms of Gondwana?-phylogeny of the spider subfamily Mynogleninae (Araneae: Linyphiidae)

    DEFF Research Database (Denmark)

    Frick, Holger; Scharff, Nikolaj

    2014-01-01

    This is the first genus-level phylogeny of the subfamily Mynogleninae. It is based on 190 morphological characters scored for 44 taxa: 37 mynoglenine taxa (ingroup) representing 15 of the 17 known genera and seven outgroup taxa representing the subfamilies Stemonyphantinae, Linyphiinae (Linyphiin...

  12. Phylogenetic relationships of subfamilies in the family Hesperiidae (Lepidoptera: Hesperioidea) from China.

    Science.gov (United States)

    Yuan, Xiangqun; Gao, Ke; Yuan, Feng; Wang, Ping; Zhang, Yalin

    2015-06-10

    Hesperiidae is one of the largest families of butterflies. Our knowledge of the higher systematics on hesperiids from China is still very limited. We infer the phylogenetic relationships of the subfamilies of Chinese skippers based on three mitochondrial genes (cytochrome b (Cytb), the NADH dehydrogenase subunit 1 (ND1) and cytochrome oxidase I (COI)). In this study, 30 species in 23 genera were included in the Bayesian and maximum likelihood analyses. The subfamily Coeliadinae, Eudaminae, Pyrginae and Heteropterinae were recovered as a monophyletic clade with strong support. The subfamily Hesperiinae formed a clade, but support for monophyly was weak. Our results imply that the five subfamilies of Chinese Hesperiidae should be divided into: Coeliadinae, Eudaminae, Pyrginae, Heteropterinae and Hesperiinae. The relationships of the five subfamilies should be as follows: Coeliadinae + (Eudaminae + (Pyrginae + (Heteropterinae + Hesperiinae))).

  13. VAMP subfamilies identified by specific R-SNARE motifs.

    Science.gov (United States)

    Rossi, Valeria; Picco, Raffaella; Vacca, Marcella; D'Esposito, Maurizio; D'Urso, Michele; Galli, Thierry; Filippini, Francesco

    2004-05-01

    In eukaryotes, interactions among the alpha-helical coiled-coil domains (CCDs) of soluble N-ethylmaleimide-sensitive factor attachment protein receptors (SNAREs) play a pivotal role in mediating the fusion among vesicles and target membranes. Surface residues of such CCDs are major candidates to regulate the specificity of membrane fusion, as they may alter local charge at the interaction layers and surface of the fusion complex, possibly modulating its formation and/or the binding of non-SNARE regulatory factors. Based on alternate patterns in surface residues, we have identified two motifs which group vesicular SNAREs in two novel subfamilies: RG-SNAREs and RD-SNAREs. The RG-SNARE CCD is common to all members of the widely conserved family of long VAMPs or longins and to yeast and non-neuronal VAMPs, possibly mediating "basic" fusion mechanisms; instead, only synaptobrevins from Bilateria share an RD-SNARE CCD, which is likely to mediate interactions to specific, yet unknown, regulatory factors and/or be the landmark of rapid fusion reactions like that mediating the release of neurotransmitters.

  14. Bacterial lipoxygenases, a new subfamily of enzymes? A phylogenetic approach.

    Science.gov (United States)

    Hansen, Jhoanne; Garreta, Albert; Benincasa, Maria; Fusté, M Carmen; Busquets, Montserrat; Manresa, Angeles

    2013-06-01

    Lipoxygenases (EC. 1.13.11.12) are a non-heme iron enzymes consisting of one polypeptide chain folded into two domains, the N-terminal domain and the catalytic moiety β-barrel domain. They catalyze the dioxygenation of 1Z,4Z-pentadiene moieties of polyunsaturated fatty acids obtaining hydroperoxy fatty acids. For years, the presence of lipoxygenases was considered a eukaryotic feature, present in mammals, plants, small marine invertebrates, and fungi, but now, some lipoxygenase sequences have been detected on prokaryotic organisms, changing the idea that lipoxygenases are exclusively a eukaryotic affair. Lipoxygenases are involved in different types of reactions on eukaryote organisms where the biological role and the structural characteristics of these enzymes are well studied. However, these aspects of the bacterial lipoxygenases have not yet been elucidated and are unknown. This revision discusses biochemical aspects, biological applications, and some characteristics of these enzymes and tries to determine the existence of a subfamily of bacterial lipoxygenases in the context of the phylogeny of prokaryotic lipoxygenases, supporting the results of phylogenetic analyzes with the comparison and discussion of structural information of the first prokaryotic lipoxygenase crystallized and other eukaryotic lipoxygenases structures.

  15. Mid-tertiary dispersal, not Gondwanan vicariance explains distribution patterns in the wax palm subfamily (Ceroxyloideae: Arecaceae)

    DEFF Research Database (Denmark)

    Trénel, Philipp; Gustafsson, Mats; Baker, W.J.

    2007-01-01

    The Ceroxyloideae is a small but heterogeneous subfamily of palms (Arecaceae, Palmae). It includes a Caribbean lineage (tribe Cyclospathae), a southern hemisphere disjunction (tribe Ceroxyleae), and an amphi-Andean element (tribe Phytelepheae), until recently considered a distinct subfamily...

  16. Differential geometry techniques for sets of nonlinear partial differential equations

    Science.gov (United States)

    Estabrook, Frank B.

    1990-01-01

    An attempt is made to show that the Cartan theory of partial differential equations can be a useful technique for applied mathematics. Techniques for finding consistent subfamilies of solutions that are generically rich and well-posed and for introducing potentials or other usefully consistent auxiliary fields are introduced. An extended sample calculation involving the Korteweg-de Vries equation is given.

  17. Tetrodotoxin as a Tool to Elucidate Sensory Transduction Mechanisms: The Case for the Arterial Chemoreceptors of the Carotid Body

    Directory of Open Access Journals (Sweden)

    Constancio Gonzalez

    2011-12-01

    Full Text Available Carotid bodies (CBs are secondary sensory receptors in which the sensing elements, chemoreceptor cells, are activated by decreases in arterial PO2 (hypoxic hypoxia. Upon activation, chemoreceptor cells (also known as Type I and glomus cells increase their rate of release of neurotransmitters that drive the sensory activity in the carotid sinus nerve (CSN which ends in the brain stem where reflex responses are coordinated. When challenged with hypoxic hypoxia, the physiopathologically most relevant stimulus to the CBs, they are activated and initiate ventilatory and cardiocirculatory reflexes. Reflex increase in minute volume ventilation promotes CO2 removal from alveoli and a decrease in alveolar PCO2 ensues. Reduced alveolar PCO2 makes possible alveolar and arterial PO2 to increase minimizing the intensity of hypoxia. The ventilatory effect, in conjunction the cardiocirculatory components of the CB chemoreflex, tend to maintain an adequate supply of oxygen to the tissues. The CB has been the focus of attention since the discovery of its nature as a sensory organ by de Castro (1928 and the discovery of its function as the origin of ventilatory reflexes by Heymans group (1930. A great deal of effort has been focused on the study of the mechanisms involved in O2 detection. This review is devoted to this topic, mechanisms of oxygen sensing. Starting from a summary of the main theories evolving through the years, we will emphasize the nature and significance of the findings obtained with veratridine and tetrodotoxin (TTX in the genesis of current models of O2-sensing.

  18. A mechanism for the polarity formation of chemoreceptors at the growth cone membrane for gradient amplification during directional sensing.

    Directory of Open Access Journals (Sweden)

    Cedric Bouzigues

    Full Text Available Accurate response to external directional signals is essential for many physiological functions such as chemotaxis or axonal guidance. It relies on the detection and amplification of gradients of chemical cues, which, in eukaryotic cells, involves the asymmetric relocalization of signaling molecules. How molecular events coordinate to induce a polarity at the cell level remains however poorly understood, particularly for nerve chemotaxis. Here, we propose a model, inspired by single-molecule experiments, for the membrane dynamics of GABA chemoreceptors in nerve growth cones (GCs during directional sensing. In our model, transient interactions between the receptors and the microtubules, coupled to GABA-induced signaling, provide a positive-feedback loop that leads to redistribution of the receptors towards the gradient source. Using numerical simulations with parameters derived from experiments, we find that the kinetics of polarization and the steady-state polarized distribution of GABA receptors are in remarkable agreement with experimental observations. Furthermore, we make predictions on the properties of the GC seen as a sensing, amplification and filtering module. In particular, the growth cone acts as a low-pass filter with a time constant approximately 10 minutes determined by the Brownian diffusion of chemoreceptors in the membrane. This filtering makes the gradient amplification resistant to rapid fluctuations of the external signals, a beneficial feature to enhance the accuracy of neuronal wiring. Since the model is based on minimal assumptions on the receptor/cytoskeleton interactions, its validity extends to polarity formation beyond the case of GABA gradient sensing. Altogether, it constitutes an original positive-feedback mechanism by which cells can dynamically adapt their internal organization to external signals.

  19. An experimentally validated panel of subfamily-specific oligonucleotide primers (V alpha 1-w29/V beta 1-w24) for the study of human T cell receptor variable V gene segment usage by polymerase chain reaction.

    Science.gov (United States)

    Genevée, C; Diu, A; Nierat, J; Caignard, A; Dietrich, P Y; Ferradini, L; Roman-Roman, S; Triebel, F; Hercend, T

    1992-05-01

    We report here the characterization of a series of T cell receptor (TcR) V alpha or V beta subfamily-specific oligonucleotide primers. Criteria that have guided the design of each oligonucleotide include appropriate thermodynamic parameters as well as differential base-pairing scores with related and unrelated target sequences. The specificity of the oligonucleotides for each V alpha or V beta subfamily was tested by polymerase chain reaction (PCR) on both a series of TcR encoding plasmid DNA and clonal T cell populations. Unexpected cross-reactivities were observed with plasmid cDNA sequences corresponding to unrelated subfamily gene segments. This led to the synthesis of additional series of oligonucleotides to obtain a relevant panel. A series of V alpha 1-w29/V beta 1-w24 TcR subfamily-specific oligonucleotides was eventually selected which generates little, if any, cross-reactivity. The use of C alpha or C beta primers for the amplification of internal positive control templates (i.e. C beta for the V alpha series and C alpha for the V beta series) has been tested in PCR performed with cDNA derived from peripheral blood lymphocytes; it was shown not to alter the amplification of the V subfamily-specific DNA fragments. This panel of oligonucleotides will be helpful in the study of TcRV gene segment usage and, thus, may lead to a better characterization of T cell responses in physiological and pathological situations.

  20. Analysis of the features and source gene composition of the AluYg6 subfamily of human retrotransposons

    Directory of Open Access Journals (Sweden)

    Brookfield John FY

    2007-07-01

    Full Text Available Abstract Background Alu elements are a family of SINE retrotransposons in primates. They are classified into subfamilies according to specific diagnostic mutations from the general Alu consensus. It is now believed that there may be several retrotranspositionally-competent source genes within an Alu subfamily. To investigate the evolution of young Alu elements it is critical to have access to complete subfamilies, which, following the release of the final human genome assembly, can now be obtained using in silico methods. Results 380 elements belonging to the young AluYg6 subfamily were identified in the human genome, a number significantly exceeding prior expectations. An AluYg6 element was also identified in the chimpanzee genome, indicating that the subfamily is older than previously estimated, and appears to have undergone a period of dormancy before its expansion. The relative contributions of back mutation and gene conversion to variation at the six diagnostic positions are examined, and cases of complete forward gene conversion events are reported. Two small subfamilies derived from AluYg6 have been identified, named AluYg6a2 and AluYg5b3, which contain 40 and 27 members, respectively. These small subfamilies are used to illustrate the ambiguity regarding Alu subfamily definition, and to assess the contribution of secondary source genes to the AluYg6 subfamily. Conclusion The number of elements in the AluYg6 subfamily greatly exceeds prior expectations, indicating that the current knowledge of young Alu subfamilies is incomplete, and that prior analyses that have been carried out using these data may have generated inaccurate results. A definition of primary and secondary source genes has been provided, and it has been shown that several source genes have contributed to the proliferation of the AluYg6 subfamily. Access to the sequence data for the complete AluYg6 subfamily will be invaluable in future computational analyses investigating

  1. Expression, refolding, purification and crystallization of the sensory domain of the TlpC chemoreceptor from Helicobacter pylori for structural studies.

    Science.gov (United States)

    Liu, Yu Chih; Roujeinikova, Anna

    2015-03-01

    Helicobacter pylori infections are associated with gastritis, duodenal and gastric ulcers and gastric adenocarcinoma. Bacterial chemotaxis, mediated by four different chemoreceptors (also termed transducer-like proteins (Tlp)), plays an important role in initial colonization and development of disease. Chemoreceptor sensory domains of H. pylori share no significant sequence similarity with those of Escherichia coli or any other non-Epsilonproteobacteria. The structural basis of how chemical signals are recognized by chemoreceptors of H. pylori is poorly understood mainly due to the lack of a robust procedure to purify their sensory domains in a soluble form. This study reports a method for extraction of the periplasmic sensory domain of transducer-like protein C (TlpC) from inclusion bodies and refolding to yield 5mg pure crystallizable protein per 1l of bacterial culture. Purified protein was monomeric in solution by size-exclusion chromatography and folded according to the circular dichroism spectrum. Crystals have been grown by the hanging-drop vapor-diffusion method using PEG 4000 as a precipitating agent. The crystals belonged to space group C2, with unit-cell parameters a=189.3, b=103.2, c=61.8Å, β=98.3. A complete X-ray diffraction data set has been collected to 2.2 Å resolution using cryocooling conditions and synchrotron radiation. Self-rotation function and Matthews coefficient calculations suggest that the asymmetric unit contains three monomers.

  2. Identification and Structure-Function Analysis of Subfamily Selective G Protein-Coupled Receptor Kinase Inhibitors

    Energy Technology Data Exchange (ETDEWEB)

    Homan, Kristoff T.; Larimore, Kelly M.; Elkins, Jonathan M.; Szklarz, Marta; Knapp, Stefan; Tesmer, John J.G. [Michigan; (Oxford)

    2015-02-13

    Selective inhibitors of individual subfamilies of G protein-coupled receptor kinases (GRKs) would serve as useful chemical probes as well as leads for therapeutic applications ranging from heart failure to Parkinson’s disease. To identify such inhibitors, differential scanning fluorimetry was used to screen a collection of known protein kinase inhibitors that could increase the melting points of the two most ubiquitously expressed GRKs: GRK2 and GRK5. Enzymatic assays on 14 of the most stabilizing hits revealed that three exhibit nanomolar potency of inhibition for individual GRKs, some of which exhibiting orders of magnitude selectivity. Most of the identified compounds can be clustered into two chemical classes: indazole/dihydropyrimidine-containing compounds that are selective for GRK2 and pyrrolopyrimidine-containing compounds that potently inhibit GRK1 and GRK5 but with more modest selectivity. The two most potent inhibitors representing each class, GSK180736A and GSK2163632A, were cocrystallized with GRK2 and GRK1, and their atomic structures were determined to 2.6 and 1.85 Å spacings, respectively. GSK180736A, developed as a Rho-associated, coiled-coil-containing protein kinase inhibitor, binds to GRK2 in a manner analogous to that of paroxetine, whereas GSK2163632A, developed as an insulin-like growth factor 1 receptor inhibitor, occupies a novel region of the GRK active site cleft that could likely be exploited to achieve more selectivity. However, neither compound inhibits GRKs more potently than their initial targets. This data provides the foundation for future efforts to rationally design even more potent and selective GRK inhibitors.

  3. Phylogenetic relationships and protein modelling revealed two distinct subfamilies of group II HKT genes between crop and model grasses.

    Science.gov (United States)

    Ariyarathna, H A Chandima K; Francki, Michael G

    2016-07-01

    Molecular evolution of large protein families in closely related species can provide useful insights on structural functional relationships. Phylogenetic analysis of the grass-specific group II HKT genes identified two distinct subfamilies, I and II. Subfamily II was represented in all species, whereas subfamily I was identified only in the small grain cereals and possibly originated from an ancestral gene duplication post divergence from the coarse grain cereal lineage. The core protein structures were highly analogous despite there being no more than 58% amino acid identity between members of the two subfamilies. Distinctly variable regions in known functional domains, however, indicated functional divergence of the two subfamilies. The subsets of codons residing external to known functional domains predicted signatures of positive Darwinian selection potentially identifying new domains of functional divergence and providing new insights on the structural function and relationships between protein members of the two subfamilies.

  4. Datziinae as a new subfamily name for the unavailable name Protopsychodinae Stebner et al., 2015, (Diptera: Psychodidae

    Directory of Open Access Journals (Sweden)

    Frauke Stebner

    2015-11-01

    Full Text Available In a recent paper a new subfamily of Psychodidae was inadequately named Protopsychodinae. This nomenclatural act cannot be considered as a valid name under ICZN regulations because the subfamily name is not based on the type genus Datzia Stebner et al., 2015, and furthermore the fossil genus Protopsychoda Azar et al., 1999 was originally described under the subfamily Psychodinae. Therefore, the new family-group name Datziinae is herein proposed.

  5. CDD/SPARCLE: functional classification of proteins via subfamily domain architectures

    Science.gov (United States)

    Marchler-Bauer, Aron; Bo, Yu; Han, Lianyi; He, Jane; Lanczycki, Christopher J.; Lu, Shennan; Chitsaz, Farideh; Derbyshire, Myra K.; Geer, Renata C.; Gonzales, Noreen R.; Gwadz, Marc; Hurwitz, David I.; Lu, Fu; Marchler, Gabriele H.; Song, James S.; Thanki, Narmada; Wang, Zhouxi; Yamashita, Roxanne A.; Zhang, Dachuan; Zheng, Chanjuan; Geer, Lewis Y.; Bryant, Stephen H.

    2017-01-01

    NCBI's Conserved Domain Database (CDD) aims at annotating biomolecular sequences with the location of evolutionarily conserved protein domain footprints, and functional sites inferred from such footprints. An archive of pre-computed domain annotation is maintained for proteins tracked by NCBI's Entrez database, and live search services are offered as well. CDD curation staff supplements a comprehensive collection of protein domain and protein family models, which have been imported from external providers, with representations of selected domain families that are curated in-house and organized into hierarchical classifications of functionally distinct families and sub-families. CDD also supports comparative analyses of protein families via conserved domain architectures, and a recent curation effort focuses on providing functional characterizations of distinct subfamily architectures using SPARCLE: Subfamily Protein Architecture Labeling Engine. CDD can be accessed at https://www.ncbi.nlm.nih.gov/Structure/cdd/cdd.shtml. PMID:27899674

  6. The Ded1/DDX3 subfamily of DEAD-box RNA helicases.

    Science.gov (United States)

    Sharma, Deepak; Jankowsky, Eckhard

    2014-01-01

    In eukaryotic organisms, the orthologs of the DEAD-box RNA helicase Ded1p from yeast and DDX3 from human form a well-defined subfamily that is characterized by high sequence conservation in their helicase core and their N- and C- termini. Individual members of this Ded1/DDX3 subfamily perform multiple functions in RNA metabolism in both nucleus and cytoplasm. Ded1/DDX3 subfamily members have also been implicated in cellular signaling pathways and are targeted by diverse viruses. In this review, we discuss the considerable body of work on the biochemistry and biology of these proteins, including the recently discovered link of human DDX3 to tumorigenesis.

  7. A new subfamily of the grasshopper (Orthoptera: Acridoidea:Gomphoceridae) from the Tibetan Plateau of China

    Institute of Scientific and Technical Information of China (English)

    Dao-Chuan Zhang; Yu-Long Zhang; Xiang-Chu Yin

    2012-01-01

    This paper reports a new subfamily,a new genus and a new species,that is,Pacrinae subfam.nov.,Pacris gen.nov and Pacris xizangensis sp.nov in Gomphoceridae.The new subfamily is allied to Orinhippinae of Gomphoceridae and it differs from the latter by wings and tympanum absent.The new genus is similar to Orinhippus Uvarov,1921 but differs from the latter in: (i) foveolae absent; (ii) tegmina absent; (iii) tympanum absent;(iv) hind margin ofpronotum with incised in the middle.Type specimens are deposited in the Museum of Hebei University,Baoding,China.

  8. Nine novel microsatellite markers for the army ant Simopelta pergandei (subfamily Ponerinae)

    DEFF Research Database (Denmark)

    Kronauer, D.J.C.; Boomsma, J.J.; Pierce, N.E.

    2011-01-01

    Simopelta (subfamily Ponerinae) army ants are specialized predators of other ants in New World tropical forests. Although they show a striking convergence in overall life-history with the well known army ants of the subfamilies Aenictinae, Dorylinae, and Ecitoninae, the genus has been little.......0) and expected heterozygosities between 0.32 and 0.85 (mean: 0.65). These genetic markers will be useful in studying the sociobiology and molecular ecology of Simopelta army ants and in elucidating convergent evolutionary trajectories that have culminated in the army ant lifestyle...

  9. New taxa of the subfamily Doryctinae Foerster (Hymenoptera: Braconidae) from French Guiana and Brazil

    NARCIS (Netherlands)

    Braet, Y.; Achterberg, van C.

    2001-01-01

    Three genera of the subfamily Doryctinae Foerster, 1862 (Hymenoptera: Braconidae) are treated and keyed: Ptesimogaster Marsh, 1965, Caingangia Marsh, 1993, and Leptodoryctes Barbalho & Penteado- Dias, 1999. The latter genus is characterised by the presence of an apical setal comb on the hind tibia.

  10. A new genus and subgenus of the subfamily Euphorinae (Hymenoptera: Braconidae) from East Asia

    NARCIS (Netherlands)

    Belokobylskij, S.A.

    1999-01-01

    Three new taxa belonging to the subfamily Euphorinae Foerster (Hymenoptera; Braconidae) are described and illustrated. Mama mariae gen. nov. & spec. nov. from southern Far East Russia and two species of the subgenus Chaetocentistes nov. of the genus Centistes Haliday. A key to species (i.e. Centiste

  11. Classification of leaf beetles from Korea. Part V. Subfamily Megalopodinae (Coleoptera: Chrysomelidae)

    OpenAIRE

    Seung Lak An

    2015-01-01

    Korean members of the subfamily Megalopodinae are redescribed; three species are recognized, among which Temnaspis bonneuili Pic is reported for the first time in Korea. Keys, diagnoses, collection locations (domestic), distributions, host plants, and biological information about all known species are provided.

  12. Classification of leaf beetles from Korea. Part V. Subfamily Megalopodinae (Coleoptera: Chrysomelidae

    Directory of Open Access Journals (Sweden)

    Seung Lak An

    2015-12-01

    Full Text Available Korean members of the subfamily Megalopodinae are redescribed; three species are recognized, among which Temnaspis bonneuili Pic is reported for the first time in Korea. Keys, diagnoses, collection locations (domestic, distributions, host plants, and biological information about all known species are provided.

  13. Generic revision of the subfamily Betylobraconinae (Hymenoptera: Braconidae) and other groups with modified fore tarsus

    NARCIS (Netherlands)

    Achterberg, van C.

    1995-01-01

    The genera of the subfamilies Betylobraconinae, Hormiinae, Lysiterminae, Pambolinae-Chremylini, and Doryctinae-Ypsistocerini are revised. A key is given to the genera of groups belonging to the cyclostome grade including species with shortened and/or (partly) widened fore tarsus. Sixteen new genera

  14. Leaf and Stem CO2 Uptake in the Three Subfamilies of the Cactaceae 1

    Science.gov (United States)

    Nobel, Park S.; Hartsock, Terry L.

    1986-01-01

    Net CO2 uptake over 24-hour periods was examined for the leaves and for the stems of 11 species of cacti representing all three subfamilies. For Pereskia aculeata, Pereskia grandifolia, and Maihuenia poeppigii (subfamily Pereskioideae), all the net shoot CO2 uptake was by the leaves and during the daytime. In contrast, for the leafless species Carnegiea gigantea, Ferocactus acanthodes, Coryphantha vivipara, and Mammillaria dioica (subfamily Cactoideae), all the shoot net CO2 uptake was by the stems and at night. Similarly, for leafless Opuntia ficus-indica (subfamily Opuntioideae), all net CO2 uptake occurred at night. For leafy members of the Opuntioideae (Pereskiopsis porteri, Quiabentia chacoensis, Austrocylindropuntia subulata), at least 88% of the shoot CO2 uptake over 24 hours was by the leaves and some CO2 uptake occurred at night. Leaves responded to the instantaneous level of photosynthetically active radiation (PAR) during the daytime, as occurs for C3 plants, whereas nocturnal CO2 uptake by stems of O. ficus-indica and F. acanthodes responded to the total daily PAR, as occurs for Crassulacean acid metabolism (CAM) plants. Thus, under the well-watered conditions employed, the Pereskioideae behaved as C3 plants, the Cactoideae behaved as CAM plants, and the Opuntioideae exhibited characteristics of both pathways. PMID:16664741

  15. New Drosophila P-like elements and reclassification of Drosophila P-elements subfamilies.

    Science.gov (United States)

    Loreto, Elgion L S; Zambra, Francis M B; Ortiz, Mauro F; Robe, Lizandra J

    2012-07-01

    Genomic searches for P-like transposable elements were performed (1) in silico in the 12 available Drosophila genomes and (2) by PCR using degenerate primers in 21 Neotropical Drosophila species. In silico searches revealed P-like sequences only in Drosophila persimilis and Drosophila willistoni. Sixteen new P-like elements were obtained by PCR. These sequences were added to sequences of previously described P-like elements, and a phylogenetic analysis was performed. The subfamilies of P-elements described in the literature (Canonical, M, O, T, and K) were included in the reconstructed tree, and all were monophyletic. However, we suggest that some subfamilies can be enlarged, other subdivided, and some new subfamilies may be proposed, totalizing eleven subfamilies, most of which contain new P-like sequences. Our analyses support the monophyly of P-like elements in Drosophilidae. We suggest that, once these elements need host-specific factors to be mobilizable, the horizontal transfer (HT) of P-like elements may be inhibited among more distant taxa. Nevertheless, HT among Drosophilidae species appears to be a common phenomenon.

  16. Four new species of the subfamily Psilodercinae (Araneae: Ochyroceratidae) from Southwest China.

    Science.gov (United States)

    Wang, Chunxia; Li, Shuqiang

    2013-01-01

    Four new species of the family Ochyroceratidae are described from Southwest China: Althepus christae sp. nov., Lecler- cera undulatus sp. nov., Psiloderces incomptus sp. nov. from Yunnan; and P. exilis sp. nov. from Guangxi. The four spe- cies belong to the subfamily Psilodercinae.

  17. Wood anatomy of the Euphorbiaceae, in particular of the subfamily Phyllanthoideae

    NARCIS (Netherlands)

    Mennega, Alberta M.W.

    1985-01-01

    The great variety in wood structure of the large family Euphorbiaceae makes it impossible to describe briefly a general wood pattern. Nevertheless, a more or less clear division into four anatomical groups can be made. A short overview is given of the wood structure of the uni-ovulate subfamilies Ac

  18. Leaf and Stem CO(2) Uptake in the Three Subfamilies of the Cactaceae.

    Science.gov (United States)

    Nobel, P S; Hartsock, T L

    1986-04-01

    Net CO(2) uptake over 24-hour periods was examined for the leaves and for the stems of 11 species of cacti representing all three subfamilies. For Pereskia aculeata, Pereskia grandifolia, and Maihuenia poeppigii (subfamily Pereskioideae), all the net shoot CO(2) uptake was by the leaves and during the daytime. In contrast, for the leafless species Carnegiea gigantea, Ferocactus acanthodes, Coryphantha vivipara, and Mammillaria dioica (subfamily Cactoideae), all the shoot net CO(2) uptake was by the stems and at night. Similarly, for leafless Opuntia ficus-indica (subfamily Opuntioideae), all net CO(2) uptake occurred at night. For leafy members of the Opuntioideae (Pereskiopsis porteri, Quiabentia chacoensis, Austrocylindropuntia subulata), at least 88% of the shoot CO(2) uptake over 24 hours was by the leaves and some CO(2) uptake occurred at night. Leaves responded to the instantaneous level of photosynthetically active radiation (PAR) during the daytime, as occurs for C(3) plants, whereas nocturnal CO(2) uptake by stems of O. ficus-indica and F. acanthodes responded to the total daily PAR, as occurs for Crassulacean acid metabolism (CAM) plants. Thus, under the well-watered conditions employed, the Pereskioideae behaved as C(3) plants, the Cactoideae behaved as CAM plants, and the Opuntioideae exhibited characteristics of both pathways.

  19. Salmonella chemoreceptors McpB and McpC mediate a repellent response to L-cystine: a potential mechanism to avoid oxidative conditions.

    Science.gov (United States)

    Lazova, Milena D; Butler, Mitchell T; Shimizu, Thomas S; Harshey, Rasika M

    2012-05-01

    Chemoreceptors McpB and McpC in Salmonella enterica have been reported to promote chemotaxis in LB motility-plate assays. Of the chemicals tested as potential effectors of these receptors, the only response was towards L-cysteine and its oxidized form, L-cystine. Although enhanced radial migration in plates suggested positive chemotaxis to both amino acids, capillary assays failed to show an attractant response to either, in cells expressing only these two chemoreceptors. In vivo fluorescence resonance energy transfer (FRET) measurements of kinase activity revealed that in wild-type bacteria, cysteine and cystine are chemoeffectors of opposing sign, the reduced form being a chemoattractant and the oxidized form a repellent. The attractant response to cysteine was mediated primarily by Tsr, as reported earlier for Escherichia coli. The repellent response to cystine was mediated by McpB/C. Adaptive recovery upon cystine exposure required the methyl-transferase/-esterase pair, CheR/CheB, but restoration of kinase activity was never complete (i.e. imperfect adaptation). We provide a plausible explanation for the attractant-like responses to both cystine and cysteine in motility plates, and speculate that the opposing signs of response to this redox pair might afford Salmonella a mechanism to gauge and avoid oxidative environments.

  20. ATP-binding cassette subfamily B member 1 (ABCB1) and subfamily C member 10 (ABCC10) are not primary resistance factors for cabazitaxel

    Institute of Scientific and Technical Information of China (English)

    Rishil J Kathawala; Yi-Jun Wang; Suneet Shukla; Yun-Kai Zhang; Saeed Alqahtani; Amal Kaddoumi; Suresh V Ambudkar; Charles R Ashby Jr; Zhe-Sheng Chen

    2015-01-01

    Introduction:ATP-binding cassette subfamily B member 1 (ABCB1) and subfamily C member 10 (ABCC10) proteins are efflux transporters that couple the energy derived from ATP hydrolysis to the translocation of toxic substances and chemotherapeutic drugs out of cells. Cabazitaxel is a novel taxane that differs from paclitaxel by its lower affinity for ATP-binding cassette (ABC) transporters. Methods:We determined the effects of cabazitaxel, a novel tubulin-binding taxane, and paclitaxel on paclitaxel-resistant, ABCB1-overexpressing KB-C2 and LLC-MDR1-WT cells and paclitaxel-resistant, ABCC10-overexpressing HEK293/ABCC10 cells by calculating the degree of drug resistance and measuring ATPase activity of the ABCB1 transporter. Results:Decreased resistance to cabazitaxel compared with paclitaxel was observed in KB-C2, LLC-MDR1-WT, and HEK293/ABCC10 cells. Moreover, cabazitaxel had low efficacy, whereas paclitaxel had high efficacy in stimulating the ATPase activity of ABCB1, indicating a direct interaction of both drugs with the transporter. Conclusion:ABCB1 and ABCC10 are not primary resistance factors for cabazitaxel compared with paclitaxel, suggesting that cabazitaxel may have a low affinity for these efflux transporters.

  1. Odontomariinae, a new middle paleozoic subfamily of slit-bearing euophaloidean gastropods (Euophalomorpha, Gastropoda)

    Science.gov (United States)

    Fryda, J.; Heidelberger, D.; Blodgett, R.B.

    2006-01-01

    A new subfamily, the Odontomariinae subfam. nov., is established herein for a distinctive group of uncoiled, slit-bearing Middle Devonian euomphalid gastropods. Its taxonomic position is based on the recent discovery of open coiled protoconchs and it is placed within the Euomphalomorpha. The genera Odontomaria Odontomaria C. F. Roemer and Tubiconcha n. gen. belonging to this new subfamily are enlarged based on studies on new material of the following species: Odontomaria semiplicata (Sandberger & Sandberger), Odontomaria gracilis n. sp., Odontomaria jankei n. sp., Odontomaria cheeneetnukensis n. sp., Odontomaria cindiprellerae n. sp. and Tubiconcha leunissi (Heidelberger, 2001). Members of the Odontomariinae were mainly sedentary organisms in high-energy, moderately shallow water. ?? 2006 E. Schweizerbart'sche Verlagsbuchhandlung.

  2. The DDX3 subfamily of the DEAD box helicases: divergent roles as unveiled by studying different organisms and in vitro assays.

    Science.gov (United States)

    Rosner, A; Rinkevich, B

    2007-01-01

    DDX3 (or Ded1p), the highly conserved subfamily of the DEAD-box RNA helicase family (40 members in humans), plays important roles in RNA metabolism. DDX3X and DDX3Y, the two human paralogous genes of this subfamily of proteins, have orthologous candidates in a diverse range of eukaryotes, from yeast and plants to animals. While DDX3Y, which is essential for normal spermatogenesis, is translated only in the testes, DDX3X protein is ubiquitously expressed, involved in RNA transcription, RNA splicing, mRNA transport, translation initiation and cell cycle regulation. Studies of recent years have revealed that DDX3X participates in HIV and hepatitis C viral infections, and in hepatocellular carcinoma, a complication of hepatitis B and hepatitis C infections. In the urochordates (i.e., Botryllus schlosseri) and in diverse invertebrate phyla (represented by model organisms such as: Drosophila, Hydra, Planaria), DDX3 proteins (termed also PL10) are involved in developmental pathways, highly expressed in adult undifferentiated soma and germ cells and in some adult and embryo's differentiating tissues. As the mechanistic and functional knowledge of DDX3 proteins is limited, we suggest assembling the available data on DDX3 proteins, from all studied organisms and in vitro assays, depicting a unified mechanistic scheme for DDX3 proteins' functions. Understanding the diverse functions of DDX3 in multicellular organisms may be particularly important for effective strategies of drug design.

  3. Data supporting the nuclear phylogenomics of the palm subfamily Arecoideae (Arecaceae).

    Science.gov (United States)

    Comer, Jason R; Zomlefer, Wendy B; Barrett, Craig F; Stevenson, Dennis Wm; Heyduk, Karolina; Leebens-Mack, James H

    2016-06-01

    This data article provides data and supplemental materials referenced in "Nuclear phylogenomics of the palm subfamily Arecoideae (Arecaceae)" (Comer et al., 2016) [1]. Raw sequence reads generated for this study are available through the Sequence Read Archive (SRA Study Accession: SRP061467). An aligned supermatrix of 168 nuclear genes for 35 taxa (34 palms and one outgroup taxon) is provided. Also provided are individual maximum likelihood gene trees used for the coalescent based analyses, output from the maximum parsimony analyses, and two figures.

  4. The gymnosperm Pinus pinea contains both AOX gene subfamilies, AOX1 and AOX2.

    Science.gov (United States)

    Frederico, António Miguel; Zavattieri, Maria Amely; Campos, Maria Doroteia; Cardoso, Hélia Guerra; McDonald, Allison E; Arnholdt-Schmitt, Birgit

    2009-12-01

    The gymnosperm Pinus pinea L. (stone pine) is a typical Mediterranean pine used for nuts and timber production, and as an ornamental around the world. Pine genomes are large in comparison to other species. The hypothesis that retrotransposons, such as gymny, made a large contribution to this alteration in genome size was recently confirmed. However, P. pinea is unique in other various aspects. P. pinea demonstrates a different pattern of gymny organization than other Pinus subgenera. Additionally, P. pinea has a highly recalcitrant behaviour in relation to standard conifer protocols for the induction of somatic embryogenesis or rooting. Because such types of cell reprogramming can be explained as a reaction of plant cells to external stress, it is of special interest to study sequence peculiarities in stress-inducible genes, such as the alternative oxidase (AOX). This is the first report containing molecular evidence for the existence of AOX in gymnosperms at the genetic level. P. pinea AOXs were isolated by a polymerase chain reaction (PCR) approach and three genes were identified. Two of the genes belong to the AOX1 subfamily and one belongs to the AOX2 subfamily. The existence of both AOX subfamilies in gymnosperms is reported here for the first time. This discovery supports the hypothesis that AOX1 and AOX2 subfamilies arose prior to the separation of gymnosperms and angiosperms, and indicates that the AOX2 is absent in monocots because of subsequent gene loss events. Polymorphic P. pinea AOX1 sequences from a selected genetic clone are presented indicating non-allelic, non-synonymous and synonymous translation products.

  5. Clonal Expansion and Cytotoxicity of TCRVβ Subfamily T Cells Induced by CML and K562 Cells

    Institute of Scientific and Technical Information of China (English)

    YupingZHang; YangqiuLi; ShaohuaChen; LijianYang; GengxinLuo; XueliZhang

    2004-01-01

    OBJECTIVE To investigate the anti-leukemia effect, the distribution and clonal expansion of TCRVβ subfamily T cells in T cells from cord blood and adult peripheral blood induced by CML cells and K562 cells in vitro. METHODS Peripheral blood T cells from one adult donor and 3 cases of cord blood were stimulated with CML cells and K562 cells and further amplified by a suspended T cell-bulk culture,in order to induce CML specific cytotoxic T lymphocytes. The induced T cells were further analyzed for the specific cytotoxicity in CML by LDH assay, the phenotype identification by indirect immunofiuorescence technique and the distribution and clonal expansion of TCRVβ subfamily by using reverse transcriptase-polymerase chain reaction (RT-PCR) and genescan analysis, respectively. RESULTS Oligoclonal and oligoclonal tendency T cells with higher specific cytotoxicity from cord blood and adult peripheral blood could be induced by stimulation with CML cells and K562 cells. CONCLUSIONS Specific cytotoxic T cells for an anti-CML effect could be induced by CML cells and K562 cells .The induced T cells which have the characteristic of specific cytotoxicity against CML cells may come from the clonal expansion of TCRVβ subfamily T cells.

  6. Computational identification and evolutional analysis of Piwi subfamily in 11 Drosophila species

    Institute of Scientific and Technical Information of China (English)

    Xue Zhou; Ya-Long Xu; Luo-Gen Cheng; Fei Li

    2008-01-01

    The complete genome sequences of 11 Drosophila species provide an opportu-nity to investigate the gene family evolution in closely related species.Drosophila Piwi subfamily,including three mcmbers,piwi,Aub and Ago3,has attracted increasing attention as it participates in the biogenesis of piRNA.Here,we identified 33 Piwi homologs from the genome of 11 Drosophila species.The full-length cDNA sequences of piwi and Aub genes were obtained by using New GENSCAN Web Server.The Ago3 homologs were diffcult regarding full-length information because they had long introns.The genomic structure of Piwf subfamily genes are highly conserved among diverse Drosophila species.Insect piwi and Aub genes have long first introns.The average length of the first intmn is 1 284 bp for piwf and 840 bp for Aub,Which is much larger than those of other introns(93 bp for Piwf and 54 bp for Aub).However,this phenomenon is not observed in mammalian piwi genes.We alSO found that there were abundant repeat sequences in both exons and introns of insect Ago3 genes.DHe to recent insertions of long terminal repeat elements in four Drosophila species.part of the third introns exhibit higher conservation thall adjacent exons and other introns.An evolutional tree created by Minimum Evolution method indicates that mamma-lian piwf genes are more closely related to the insect Ag03 Piwi subfamily.

  7. Designing exons for human olfactory receptor gene subfamilies using a mathematical paradigm

    Indian Academy of Sciences (India)

    Sk Sarif Hassan; Pabitra Pal Choudhury; Amita Pal; R L Brahmachary; Arunava Goswami

    2010-09-01

    Ligands for only two human olfactory receptors are known. One of them, OR1D2, binds to Bourgeonal, a volatile chemical constituent of the fragrance of the mythical flower, Lily of the valley or Our Lady’s tears, Convallaria majalis (also the national flower of Finland). OR1D2, OR1D4 and OR1D5 are three full-length olfactory receptors present in an olfactory locus in the human genome. These receptors are more than 80% identical in DNA sequences and have 108 base pair mismatches among them. Apparently, these mismatch positions show no striking pattern using computer pattern recognition tools. In an attempt to find a mathematical rule in those mismatches, we find that an L-system generated sequence can be inserted into the OR1D2 subfamily-specific star model and novel full-length olfactory receptors can be generated. This remarkable mathematical principle could be utilized for making new subfamily olfactory receptor members from any olfactory receptor subfamily. The aroma and electronic nose industry might utilize this rule in future.

  8. Gene Structures, Classification, and Expression Models of the DREB Transcription Factor Subfamily in Populus trichocarpa

    Directory of Open Access Journals (Sweden)

    Yunlin Chen

    2013-01-01

    Full Text Available We identified 75 dehydration-responsive element-binding (DREB protein genes in Populus trichocarpa. We analyzed gene structures, phylogenies, domain duplications, genome localizations, and expression profiles. The phylogenic construction suggests that the PtrDREB gene subfamily can be classified broadly into six subtypes (DREB A-1 to A-6 in Populus. The chromosomal localizations of the PtrDREB genes indicated 18 segmental duplication events involving 36 genes and six redundant PtrDREB genes were involved in tandem duplication events. There were fewer introns in the PtrDREB subfamily. The motif composition of PtrDREB was highly conserved in the same subtype. We investigated expression profiles of this gene subfamily from different tissues and/or developmental stages. Sixteen genes present in the digital expression analysis had high levels of transcript accumulation. The microarray results suggest that 18 genes were upregulated. We further examined the stress responsiveness of 15 genes by qRT-PCR. A digital northern analysis showed that the PtrDREB17, 18, and 32 genes were highly induced in leaves under cold stress, and the same expression trends were shown by qRT-PCR. Taken together, these observations may lay the foundation for future functional analyses to unravel the biological roles of Populus’ DREB genes.

  9. Genesis of the vertebrate FoxP subfamily member genes occurred during two ancestral whole genome duplication events.

    Science.gov (United States)

    Song, Xiaowei; Tang, Yezhong; Wang, Yajun

    2016-08-22

    The vertebrate FoxP subfamily genes play important roles in the construction of essential functional modules involved in physiological and developmental processes. To explore the adaptive evolution of functional modules associated with the FoxP subfamily member genes, it is necessary to study the gene duplication process. We detected four member genes of the FoxP subfamily in sea lampreys (a representative species of jawless vertebrates) through genome screenings and phylogenetic analyses. Reliable paralogons (i.e. paralogous chromosome segments) have rarely been detected in scaffolds of FoxP subfamily member genes in sea lampreys due to the considerable existence of HTH_Tnp_Tc3_2 transposases. However, these transposases did not alter gene numbers of the FoxP subfamily in sea lampreys. The coincidence between the "1-4" gene duplication pattern of FoxP subfamily genes from invertebrates to vertebrates and two rounds of ancestral whole genome duplication (1R- and 2R-WGD) events reveal that the FoxP subfamily of vertebrates was quadruplicated in the 1R- and 2R-WGD events. Furthermore, we deduced that a synchronous gene duplication process occurred for the FoxP subfamily and for three linked gene families/subfamilies (i.e. MIT family, mGluR group III and PLXNA subfamily) in the 1R- and 2R-WGD events using phylogenetic analyses and mirror-dendrogram methods (i.e. algorithms to test protein-protein interactions). Specifically, the ancestor of FoxP1 and FoxP3 and the ancestor of FoxP2 and FoxP4 were generated in 1R-WGD event. In the subsequent 2R-WGD event, these two ancestral genes were changed into FoxP1, FoxP2, FoxP3 and FoxP4. The elucidation of these gene duplication processes shed light on the phylogenetic relationships between functional modules of the FoxP subfamily member genes.

  10. Frames of exponentials:lower frame bounds for finite subfamilies, and approximation of the inverse frame operator

    DEFF Research Database (Denmark)

    Christensen, Ole; Lindner, Alexander M

    2001-01-01

    We give lower frame bounds for finite subfamilies of a frame of exponentials {e(i lambdak(.))}k is an element ofZ in L-2(-pi,pi). We also present a method for approximation of the inverse frame operator corresponding to {e(i lambdak(.))}k is an element ofZ, where knowledge of the frame bounds for...... for finite subfamilies is crucial. (C) 2001 Elsevier Science Inc. All rights reserved....

  11. The formation of the polyploid hybrids from different subfamily fish crossings and its evolutionary significance.

    Science.gov (United States)

    Liu, Shaojun; Qin, Qinbo; Xiao, Jun; Lu, Wenting; Shen, Jiamin; Li, Wei; Liu, Jifang; Duan, Wei; Zhang, Chun; Tao, Min; Zhao, Rurong; Yan, Jinpeng; Liu, Yun

    2007-06-01

    This study provides genetic evidences at the chromosome, DNA content, DNA fragment and sequence, and morphological levels to support the successful establishment of the polyploid hybrids of red crucian carp x blunt snout bream, which belonged to a different subfamily of fish (Cyprininae subfamily and Cultrinae subfamily) in the catalog. We successfully obtained the sterile triploid hybrids and bisexual fertile tetraploid hybrids of red crucian carp (RCC) (female symbol) x blunt snout bream (BSB) (male symbol) as well as their pentaploid hybrids. The triploid hybrids possessed 124 chromosomes with two sets from RCC and one set from BSB; the tetraploid hybrids had 148 chromosomes with two sets from RCC and two sets from BSB. The females of tetraploid hybrids produced unreduced tetraploid eggs that were fertilized with the haploid sperm of BSB to generate pentaploid hybrids with 172 chromosomes with three sets from BSB and two sets from RCC. The ploidy levels of triploid, tetraploid, and pentaploid hybrids were confirmed by counting chromosomal number, forming chromosomal karyotype, and measuring DNA content and erythrocyte nuclear volume. The similar and different DNA fragments were PCR amplified and sequenced in triploid, tetraploid hybrids, and their parents, indicating their molecular genetic relationship and genetic markers. In addition, this study also presents results about the phenotypes and feeding habits of polyploid hybrids and discusses the formation mechanism of the polyploid hybrids. It is the first report on the formation of the triploid, tetraploid, and pentaploid hybrids by crossing parents with a different chromosome number in vertebrates. The formation of the polyploid hybrids is potentially interesting in both evolution and fish genetic breeding.

  12. Phylogeny and evolutionary patterns in the Dwarf crayfish subfamily (Decapoda: Cambarellinae.

    Directory of Open Access Journals (Sweden)

    Carlos Pedraza-Lara

    Full Text Available The Dwarf crayfish or Cambarellinae, is a morphologically singular subfamily of decapod crustaceans that contains only one genus, Cambarellus. Its intriguing distribution, along the river basins of the Gulf Coast of United States (Gulf Group and into Central México (Mexican Group, has until now lacked of satisfactory explanation. This study provides a comprehensive sampling of most of the extant species of Cambarellus and sheds light on its evolutionary history, systematics and biogeography. We tested the impact of Gulf Group versus Mexican Group geography on rates of cladogenesis using a maximum likelihood framework, testing different models of birth/extinction of lineages. We propose a comprehensive phylogenetic hypothesis for the subfamily based on mitochondrial and nuclear loci (3,833 bp using Bayesian and Maximum Likelihood methods. The phylogenetic structure found two phylogenetic groups associated to the two main geographic components (Gulf Group and Mexican Group and is partially consistent with the historical structure of river basins. The previous hypothesis, which divided the genus into three subgenera based on genitalia morphology was only partially supported (P = 0.047, resulting in a paraphyletic subgenus Pandicambarus. We found at least two cases in which phylogenetic structure failed to recover monophyly of recognized species while detecting several cases of cryptic diversity, corresponding to lineages not assigned to any described species. Cladogenetic patterns in the entire subfamily are better explained by an allopatric model of speciation. Diversification analyses showed similar cladogenesis patterns between both groups and did not significantly differ from the constant rate models. While cladogenesis in the Gulf Group is coincident in time with changes in the sea levels, in the Mexican Group, cladogenesis is congruent with the formation of the Trans-Mexican Volcanic Belt. Our results show how similar allopatric

  13. Reassessment of Species Diversity of the Subfamily Denticollinae (Coleoptera: Elateridae through DNA Barcoding.

    Directory of Open Access Journals (Sweden)

    Taeman Han

    Full Text Available The subfamily Denticollinae is a taxonomically diverse group in the family Elateridae. Denticollinae includes many morphologically similar species and crop pests, as well as many undescribed species at each local fauna. To construct a rapid and reliable identification system for this subfamily, the effectiveness of molecular species identification was assessed based on 421 cytochrome c oxidase subunit I (COI sequences of 84 morphologically identified species. Among the 84 morphospecies, molecular species identification of 60 species (71.4% was consistent with their morphological identifications. Six cryptic and/or pseudocryptic species with large genetic divergence (>5% were confirmed by their sympatric or allopatric distributions. However, 18 species, including a subspecies, had ambiguous genetic distances and shared overlapping intra- and interspecific genetic distances (range: 2.12%-3.67% suggesting incomplete lineage sorting, introgression of mitochondrial genome, or affection by endosymbionts, such as Wolbachia infection, between species and simple genetic variation within species. In this study, we propose a conservative threshold of 3.6% for convenient molecular operational taxonomic unit (MOTU identification in the subfamily Denticollinae based on the results of pairwise genetic distances analyses using neighbor-joining, mothur, Automatic Barcode Gap Discovery analysis, and tree-based species delimitation by Poisson Tree Processes analysis. Using the 3.6% threshold, we identified 87 MOTUs and found 8 MOTUs in the interval between 2.5% to 3.5%. Evaluation of MOTUs identified in this range requires integrative species delimitation, including review of morphological and ecological differences as well as sensitive genetic markers. From this study, we confirmed that COI sequence is useful for reassessing species diversity for polymorphic and polytypic species occurring in sympatric and allopatric distributions, and for a single species having

  14. Data supporting the nuclear phylogenomics of the palm subfamily Arecoideae (Arecaceae

    Directory of Open Access Journals (Sweden)

    Jason R. Comer

    2016-06-01

    Full Text Available This data article provides data and supplemental materials referenced in “Nuclear phylogenomics of the palm subfamily Arecoideae (Arecaceae” (Comer et al., 2016 [1]. Raw sequence reads generated for this study are available through the Sequence Read Archive (SRA Study Accession: SRP061467. An aligned supermatrix of 168 nuclear genes for 35 taxa (34 palms and one outgroup taxon is provided. Also provided are individual maximum likelihood gene trees used for the coalescent based analyses, output from the maximum parsimony analyses, and two figures.

  15. Phthiria sharafi sp. nov., a new record of the subfamily Phthiriinae (Bombyliidae, Diptera) from Saudi Arabia.

    Science.gov (United States)

    El-Hawagry, Magdi S; Al Dhafer, Hathal M

    2014-10-10

    This new species (Phthiria sharafi sp. nov.) represents the first record of the subfamily Phthiriinae (Bombyliidae, Diptera) from Saudi Arabia. The species was collected from Garf Raydah Protected Area, Abha, Asir Province, south-western part of Saudi Arabia, using a Malaise trap erected in a site rich in olive, cactus and Juniper trees. The type locality has an Afrotropical influence, with the Afrotropical elements predominant, and a closer affiliation to the Afrotropical region than to the Palearctic region or the Eremic zone. 

  16. Characteristics of the LrhA subfamily of transcriptional regulators from Sinorhizobium meliloti

    Institute of Scientific and Technical Information of China (English)

    Mingsheng Qi; Li Luo; Haiping Cheng; Jiabi Zhu; Guanqiao Yu

    2008-01-01

    In our previous work, we identified 94 putative genes encoding LysR-type transcriptional regulators from Sinorhizobium meliloti. All of these putative lysR genes were mutagenized using plasmid insertions to determine their phenotypes. Six LysR-type regulators, encoded by mutants SMa1979, SMb20715, SMc00820, SMc04163, SMc03975,and SMc04315, showed similar amino acid sequences (30%)and shared the conserved DNA-binding domain with LrhA,HexA, or DgdR. Phenotype analysis of these gene mutants indicated that the regulators control the swimming behaviors of the bacteria, production of quorum-sensing signals, and secretion of extracellular proteins. These characteristics are very similar to those of LrhA, HexA, and DgdR.Thus, we refer to this group as the LrhA subfamily. Sequence analysis showed that a great number of homologous genes of the LrhA subfamily were distributed in the α,β, and γsubdivisions of proteobacteria, and a few in actinobacteria. These findings could provide new clues to the roles of the LysR gene family.

  17. Nonlinear interaction of intense hypergeometric Gaussian subfamily laser beams in plasma

    Science.gov (United States)

    Sobhani, H.; Vaziri (Khamedi), M.; Rooholamininejad, H.; Bahrampour, A. R.

    2016-07-01

    Propagation of Hypergeometric-Gaussian laser beam in a nonlinear plasma medium is investigated by considering the Source Dependent Expansion method. A subfamily of Hypergeometric-Gaussian beams with a non-negative, even and integer radial index, can be expressed as the linear superposition of finite number of Laguerre-Gaussian functions. Propagation of Hypergeometric-Gaussian beams in a nonlinear plasma medium depends on the value of radial index. The bright rings' number of these beams is changed during the propagation in plasma medium. The effect of beam vortex charge number l and initial (input) beam intensity on the self-focusing of Hypergeometric-Gaussian beams is explored. Also, by choosing the suitable initial conditions, Hypergeometric-Gaussian subfamily beams can be converted to one or more mode components that a typical of mode conversion may be occurred. The self-focusing of these winding beams can be used to control the focusing force and improve the electron bunch quality in laser plasma accelerators.

  18. Flight patterns and sex ratio of beetles of the subfamily Dynastinae (Coleoptera, Melolonthidae

    Directory of Open Access Journals (Sweden)

    Larissa Simões Corrêa de Albuquerque

    2016-09-01

    Full Text Available ABSTRACT Dynastinae is one of the most representative subfamilies of Melolonthidae (Scarabaeoidea and has considerable ecological importance due mainly to interactions with plants of the families Araceae and Annonaceae. This relationship has led to the evolution of nocturnal activity patterns, which are influenced by environmental conditions. In the present study, abiotic factors were investigated to comprehend the influence on the flight patterns and identify the sex ratio of beetles from this subfamily. A study was conducted at Campo de Instrução Marechal Newton Cavalcanti in northeastern Brazil between December 2010 and November 2011. Thirteen species of Dynastinae were identified, most of which were from the genus Cyclocephala. Abundance and richness were greater in the dry season. Six species exhibited peak flight activity at specific periods of the night. More females than males were recorded for Cyclocephala distincta and C. paraguayensis. The present findings suggest that rainfall reduces the flight activity of these beetles and different time schedules may be related to mating behavior, foraging behavior and the avoidance of interspecific resource competition.

  19. A consistent nomenclature of antimicrobial peptides isolated from frogs of the subfamily Phyllomedusinae.

    Science.gov (United States)

    Amiche, Mohamed; Ladram, Ali; Nicolas, Pierre

    2008-11-01

    A growing number of cationic antimicrobial peptides have been isolated from the skin of hylid frogs belonging to the Phyllomedusinae subfamily. The amino acid sequences of these peptides are currently located in several databases under identifiers with no consistent system of nomenclature to describe them. In order to provide a workable terminology for antimicrobial peptides from Phyllomedusid frogs, we have made a systematic effort to collect, analyze, and classify all the Phyllomedusid peptide sequences available in databases. We propose that frogs belonging to the Phyllomedusinae subfamily should be described by the species names set out in Amphibian Species of the World: http://research.amnh.org/herpetology/amphibia/index.php, American Museum of Natural History, New York, USA. Multiple alignments analysis of at least 80 antimicrobial peptides isolated from 12 Phyllomedusinae species were distributed in seven distinct peptide families including dermaseptin, phylloseptin, plasticin, dermatoxin, phylloxin, hyposin and orphan peptides, and will be considered as the name of the headgroup of each family. The parent peptide's name should be followed by the first upper letter of the species for orthologous peptides and publication date determines priority. For example, the abbreviation B for bicolor and H for hypochondrialis. When two species begin with the same letter, two letters in upper case should be used (the first letter followed by the second or the third letter and so on). For example, the abbreviation DI for distincta, DU for duellmani, VA for vaillanti and VN for vanzolinii. Paralogous peptides should bear letter(s) in upper case followed by numbers.

  20. Two CRM protein subfamilies cooperate in the splicing of group IIB introns in chloroplasts.

    Science.gov (United States)

    Asakura, Yukari; Bayraktar, Omer Ali; Barkan, Alice

    2008-11-01

    Chloroplast genomes in angiosperms encode approximately 20 group II introns, approximately half of which are classified as subgroup IIB. The splicing of all but one of the subgroup IIB introns requires a heterodimer containing the peptidyl-tRNA hydrolase homolog CRS2 and one of two closely related proteins, CAF1 or CAF2, that harbor a recently recognized RNA binding domain called the CRM domain. Two CRS2/CAF-dependent introns require, in addition, a CRM domain protein called CFM2 that is only distantly related to CAF1 and CAF2. Here, we show that CFM3, a close relative of CFM2, associates in vivo with those CRS2/CAF-dependent introns that are not CFM2 ligands. Mutant phenotypes in rice and Arabidopsis support a role for CFM3 in the splicing of most of the introns with which it associates. These results show that either CAF1 or CAF2 and either CFM2 or CFM3 simultaneously bind most chloroplast subgroup IIB introns in vivo, and that the CAF and CFM subunits play nonredundant roles in splicing. These results suggest that the expansion of the CRM protein family in plants resulted in two subfamilies that play different roles in group II intron splicing, with further diversification within a subfamily to accommodate multiple intron ligands.

  1. Myosin Binding Protein-C Slow: An Intricate Subfamily of Proteins

    Directory of Open Access Journals (Sweden)

    Maegen A. Ackermann

    2010-01-01

    Full Text Available Myosin binding protein C (MyBP-C consists of a family of thick filament associated proteins. Three isoforms of MyBP-C exist in striated muscles: cardiac, slow skeletal, and fast skeletal. To date, most studies have focused on the cardiac form, due to its direct involvement in the development of hypertrophic cardiomyopathy. Here we focus on the slow skeletal form, discuss past and current literature, and present evidence to support that: (i MyBP-C slow comprises a subfamily of four proteins, resulting from complex alternative shuffling of the single MyBP-C slow gene, (ii the four MyBP-C slow isoforms are expressed in variable amounts in different skeletal muscles, (iii at least one MyBP-C slow isoform is preferentially found at the periphery of M-bands and (iv the MyBP-C slow subfamily may play important roles in the assembly and stabilization of sarcomeric M- and A-bands and regulate the contractile properties of the actomyosin filaments.

  2. Phylogenetic relationships between flies of the Tephritinae subfamily (Diptera, Tephritidae) and their symbiotic bacteria.

    Science.gov (United States)

    Mazzon, Luca; Martinez-Sañudo, Isabel; Simonato, Mauro; Squartini, Andrea; Savio, Claudia; Girolami, Vincenzo

    2010-07-01

    The Tephritinae is considered the most specialized subfamily of fruit flies, predominantly infesting flowerheads of Asteraceae. Some species are known to host specific non-culturable symbiont bacteria ("Candidatus Stammerula spp.") in the midgut. In this work we (i) examined the phylogenetic relationships among the insect hosts, (ii) investigated the presence of bacteria in other hitherto unexamined species, and (iii) evaluated the phylogenetic congruence between insects and symbionts. A total of 33 Tephritinae species in 17 different genera were analyzed. Two regions of the mitochondrial DNA (16S rDNA and COI-tRNALeu-COII) were examined in the insect host, while the 16S was analyzed in the bacteria. From the phylogenetic trees, four of the five tribes considered were statistically supported by each of the clustering methods used. Species belonging to the tribe Noeetini never clustered at significant levels. The phylogenetic COI-tRNALeu-COII tree showed internal nodes more highly supported than the 16S phylogeny. The analysis of the distribution of symbiosis across the subfamily has highlighted the presence of bacteria only in the tribe Tephritini and in the genus Noeeta from the tribe Noeetini. A cophylogenetic analysis revealed a substantial congruence between hosts and symbionts. The interesting exceptions can be justified by events like losses, duplications and hosts switching opportunities, which are likely to arise during the biological cycle of the fly in consideration of the extracellular status of these symbionts.

  3. The Evolutionary History of R2R3-MYB Proteins Across 50 Eukaryotes: New Insights Into Subfamily Classification and Expansion.

    Science.gov (United States)

    Du, Hai; Liang, Zhe; Zhao, Sen; Nan, Ming-Ge; Tran, Lam-Son Phan; Lu, Kun; Huang, Yu-Bi; Li, Jia-Na

    2015-06-05

    R2R3-MYB proteins (2R-MYBs) are one of the main transcription factor families in higher plants. Since the evolutionary history of this gene family across the eukaryotic kingdom remains unknown, we performed a comparative analysis of 2R-MYBs from 50 major eukaryotic lineages, with particular emphasis on land plants. A total of 1548 candidates were identified among diverse taxonomic groups, which allowed for an updated classification of 73 highly conserved subfamilies, including many newly identified subfamilies. Our results revealed that the protein architectures, intron patterns, and sequence characteristics were remarkably conserved in each subfamily. At least four subfamilies were derived from early land plants, 10 evolved from spermatophytes, and 19 from angiosperms, demonstrating the diversity and preferential expansion of this gene family in land plants. Moreover, we determined that their remarkable expansion was mainly attributed to whole genome and segmental duplication, where duplicates were preferentially retained within certain subfamilies that shared three homologous intron patterns (a, b, and c) even though up to 12 types of patterns existed. Through our integrated distributions, sequence characteristics, and phylogenetic tree analyses, we confirm that 2R-MYBs are old and postulate that 3R-MYBs may be evolutionarily derived from 2R-MYBs via intragenic domain duplication.

  4. The role of morpho-anatomical traits of the leaves in the taxonomy of Kalanchoideae Berg. subfamily (Crassulaceae DC.

    Directory of Open Access Journals (Sweden)

    Myhajlo A. Chernetskyy

    2012-03-01

    Full Text Available The paper presents the results of the analysis of the morphological and anatomical structure of leaves of 35 species of the genus Kalanchoë Adans. (Crassulaceae DC. in the taxonomic aspect of the subfamily Kalanchoideae Berg. Based on own studies and literature analyses of the flower morphology, embryology, karyology, vascular anatomy of stem and molecular genetics, the author has found that the most appropriate taxonomic system of the subfamily Kalanchoideae assumes existence of one genus Kalanchoë divided into three sections:Bryophyllum (Salisb. Boit. & Mann.,Eukalanchoë Boit. & Mann. and Kitchingia (Bak. Boit. & Mann. Distinguishing three separate genera Bryophyllum Salisb., Kalanchoё Adans. and Kitchingia Bak., as has been the case throughout the history of the subfamily Kalanchoideae, is hardly possible due to existence of “intermediate” species.

  5. Quill mites of the subfamily Picobiinae (Acari: Syringophilidae) associated with woodpeckers (Aves: Piciformes: Picidae).

    Science.gov (United States)

    Skoracki, Maciej; Unsoeld, Markus; Kavetska, Katarzyna; Kaszewska, Katarzyna

    2014-03-01

    The paper contains a review of quill mites of the subfamily Picobiinae (Acari: Prostigmata: Syringophilidae) associated with woodpeckers (Aves: Piciformes: Picidae). Three new species are described: Picobia mentalis Skoracki et Unsoeld sp. nov. from Picus mentalis Temminck, Neopicobia ea Skoracki et Unsoeld sp. nov. from Celeus flavus (St. Mueller) (type host), C. elegans (St. Mueller), C. torquatus (Boddaert), and Neopicobia freya Skoracki et Unsoeld sp. nov. from Dryocopus galeatus (Temminck) (type host) and Piculus rubiginosus (Swainson). Additionally, six new host species for Picobia heeri Haller, 1878 and 12 new host species for Picobia dryobatis (Fritsch, 1956) are reported. A complete list of the picobiines parasitising birds of the family Picidae is presented in the tabular form.

  6. Relevant use of Klotho in FGF19 subfamily signaling system in vivo.

    Science.gov (United States)

    Tomiyama, Ken-ichi; Maeda, Ryota; Urakawa, Itaru; Yamazaki, Yuji; Tanaka, Tomohiro; Ito, Shinji; Nabeshima, Yoko; Tomita, Tsutomu; Odori, Shinji; Hosoda, Kiminori; Nakao, Kazuwa; Imura, Akihiro; Nabeshima, Yo-ichi

    2010-01-26

    Alpha-Klotho (alpha-Kl) and its homolog, beta-Klotho (beta-Kl) are key regulators of mineral homeostasis and bile acid/cholesterol metabolism, respectively. FGF15/ humanFGF19, FGF21, and FGF23, members of the FGF19 subfamily, are believed to act as circulating metabolic regulators. Analyses of functional interactions between alpha- and beta-Kl and FGF19 factors in wild-type, alpha-kl(-/-), and beta-kl(-/-) mice revealed a comprehensive regulatory scheme of mineral homeostasis involving the mutually regulated positive/negative feedback actions of alpha-Kl, FGF23, and 1,25(OH)(2)D and an analogous regulatory network composed of beta-Kl, FGF15/humanFGF19, and bile acids that regulate bile acid/cholesterol metabolism. Contrary to in vitro data, beta-Kl is not essential for FGF21 signaling in adipose tissues in vivo, because (i) FGF21 signals are transduced in the absence of beta-Kl, (ii) FGF21 could not be precipitated by beta-Kl, and (iii) essential phenotypes in Fgf21(-/-) mice (decreased expressions of Hsl and Atgl in WAT) were not replicated in beta-kl(-/-) mice. These findings suggest the existence of Klotho-independent FGF21 signaling pathway(s) where undefined cofactors are involved. One-to-one functional interactions such as alpha-Klotho/FGF23, beta-Klotho/FGF15 (humanFGF19), and undefined cofactor/FGF21 would result in tissue-specific signal transduction of the FGF19 subfamily.

  7. Heterodimerization within the TREK channel subfamily produces a diverse family of highly regulated potassium channels.

    Science.gov (United States)

    Levitz, Joshua; Royal, Perrine; Comoglio, Yannick; Wdziekonski, Brigitte; Schaub, Sébastien; Clemens, Daniel M; Isacoff, Ehud Y; Sandoz, Guillaume

    2016-04-12

    Twik-related K(+) channel 1 (TREK1), TREK2, and Twik-related arachidonic-acid stimulated K(+) channel (TRAAK) form the TREK subfamily of two-pore-domain K(+) (K2P) channels. Despite sharing up to 78% sequence homology and overlapping expression profiles in the nervous system, these channels show major differences in their regulation by physiological stimuli. For instance, TREK1 is inhibited by external acidification, whereas TREK2 is activated. Here, we investigated the ability of the members of the TREK subfamily to assemble to form functional heteromeric channels with novel properties. Using single-molecule pull-down (SiMPull) from HEK cell lysate and subunit counting in the plasma membrane of living cells, we show that TREK1, TREK2, and TRAAK readily coassemble. TREK1 and TREK2 can each heterodimerize with TRAAK, but do so less efficiently than with each other. We functionally characterized the heterodimers and found that all combinations form outwardly rectifying potassium-selective channels but with variable voltage sensitivity and pH regulation. TREK1-TREK2 heterodimers show low levels of activity at physiological external pH but, unlike their corresponding homodimers, are activated by both acidic and alkaline conditions. Modeling based on recent crystal structures, along with mutational analysis, suggests that each subunit within a TREK1-TREK2 channel is regulated independently via titratable His. Finally, TREK1/TRAAK heterodimers differ in function from TRAAK homodimers in two critical ways: they are activated by both intracellular acidification and alkalinization and are regulated by the enzyme phospholipase D2. Thus, heterodimerization provides a means for diversifying functionality through an expansion of the channel types within the K2P channels.

  8. That awkward age for butterflies: insights from the age of the butterfly subfamily Nymphalinae (Lepidoptera: Nymphalidae).

    Science.gov (United States)

    Wahlberg, Niklas

    2006-10-01

    The study of the historical biogeography of butterflies has been hampered by a lack of well-resolved phylogenies and a good estimate of the temporal span over which butterflies have evolved. Recently there has been surge of phylogenetic hypotheses for various butterfly groups, but estimating ages of divergence is still in its infancy for this group of insects. The main problem has been the sparse fossil record for butterflies. In this study I have used a surprisingly good fossil record for the subfamily Nymphalinae (Lepidoptera: Nymphalidae) to estimate the ages of diversification of major lineages using Bayesian relaxed clock methods. I have investigated the effects of varying priors on posterior estimates in the analyses. For this data set, it is clear that the prior of the rate of molecular evolution at the ingroup node had the largest effect on the results. Taking this into account, I have been able to arrive at a plausible history of lineage splits, which appears to be correlated with known paleogeological events. The subfamily appears to have diversified soon after the K/T event about 65 million years ago. Several splits are coincident with major paleogeological events, such as the connection of the African and Asian continents about 21 million years ago and the presence of a peninsula of land connecting the current Greater Antilles to the South American continent 35 to 33 million years ago. My results suggest that the age of Nymphalidae is older than the 70 million years speculated to be the age of butterflies as a whole.

  9. Comparative Mitogenomic Analysis of Species Representing Six Subfamilies in the Family Tenebrionidae

    Directory of Open Access Journals (Sweden)

    Hong-Li Zhang

    2016-05-01

    Full Text Available To better understand the architecture and evolution of the mitochondrial genome (mitogenome, mitogenomes of ten specimens representing six subfamilies in Tenebrionidae were selected, and comparative analysis of these mitogenomes was carried out in this study. Ten mitogenomes in this family share a similar gene composition, gene order, nucleotide composition, and codon usage. In addition, our results show that nucleotide bias was strongly influenced by the preference of codon usage for A/T rich codons which significantly correlated with the G + C content of protein coding genes (PCGs. Evolutionary rate analyses reveal that all PCGs have been subjected to a purifying selection, whereas 13 PCGs displayed different evolution rates, among which ATPase subunit 8 (ATP8 showed the highest evolutionary rate. We inferred the secondary structure for all RNA genes of Tenebrio molitor (Te2 and used this as the basis for comparison with the same genes from other Tenebrionidae mitogenomes. Some conserved helices (stems and loops of RNA structures were found in different domains of ribosomal RNAs (rRNAs and the cloverleaf structure of transfer RNAs (tRNAs. With regard to the AT-rich region, we analyzed tandem repeat sequences located in this region and identified some essential elements including T stretches, the consensus motif at the flanking regions of T stretch, and the secondary structure formed by the motif at the 3′ end of T stretch in major strand, which are highly conserved in these species. Furthermore, phylogenetic analyses using mitogenomic data strongly support the relationships among six subfamilies: ((Tenebrionidae incertae sedis + (Diaperinae + Tenebrioninae + (Pimeliinae + Lagriinae, which is consistent with phylogenetic results based on morphological traits.

  10. Australian water mites of the subfamily Notoaturinae Besch (Acari: Hydrachnidia: Aturidae), with the description of 24 new species

    NARCIS (Netherlands)

    H. Smit

    2010-01-01

    New data are presented on the subfamily Notoaturinae from Australia. Twenty-four new species are described: Austraturus aculeatus n. sp., A. canaliculatus n. sp., A. lamingtonensis n. sp., A. longigenitalis n. sp., A. montanus n. sp., A. otwayensis n. sp., A. tasmanicus n. sp., Azugaturus gibberipal

  11. Mid-Tertiary dispersal, not Gondwanan vicariance explains distribution patterns in the wax palm subfamily (Ceroxyloideae: Arecaceae).

    Science.gov (United States)

    Trénel, Philipp; Gustafsson, Mats H G; Baker, William J; Asmussen-Lange, Conny B; Dransfield, John; Borchsenius, Finn

    2007-10-01

    The Ceroxyloideae is a small but heterogeneous subfamily of palms (Arecaceae, Palmae). It includes a Caribbean lineage (tribe Cyclospathae), a southern hemisphere disjunction (tribe Ceroxyleae), and an amphi-Andean element (tribe Phytelepheae), until recently considered a distinct subfamily (Phytelephantoideae) due to its highly derived morphology. A variety of hypotheses have been proposed to account for the biogeography of the subfamily, involving Gondwanan vicariance, austral interplate dispersal from South America to Australia via Antarctica, Andean orogeny, and Pleistocene refuges. We assessed the systematic classification and biogeography of the group based on a densely sampled phylogeny using >5.5kb of DNA sequences from three plastid and two nuclear genomic regions. The subfamily and each of its three tribes were resolved as monophyletic with high support. Divergence time estimates based on penalized likelihood and Bayesian dating methods indicate that Gondwanan vicariance is highly unlikely as an explanation for basic disjunctions in tribe Ceroxyleae. Alternative explanations include a mid-Tertiary trans-Atlantic/trans-African dispersal track and the "lemurian stepping stones" hypothesis. Austral interplate dispersal of Oraniopsis to Australia could have occurred, but apparently only in the mid-Eocene/early Oligocene interval after global cooling had begun. Our data do not support Pleistocene climatic changes as drivers for speciation in the Andean-centered Phytelepheae as previously proposed. Radiation in this tribe coincides largely with the major uplift of the Andes, favoring Andean orogeny over Pleistocene climatic changes as a possible speciation-promoting factor in this tribe.

  12. Cloning of MASK, a novel member of the mammalian germinal center kinase III subfamily, with apoptosis-inducing properties

    DEFF Research Database (Denmark)

    Dan, Ippeita; Ong, Shao-En; Watanabe, Norinobu M

    2002-01-01

    We have cloned a novel human GCK family kinase that has been designated as MASK (Mst3 and SOK1-related kinase). MASK is widely expressed and encodes a protein of 416 amino acid residues, with an N-terminal kinase domain and a unique C-terminal region. Like other GCK-III subfamily kinases, MASK do...

  13. Proteins with an alpha/beta hydrolase fold: Relationships between subfamilies in an ever-growing superfamily.

    Science.gov (United States)

    Lenfant, Nicolas; Hotelier, Thierry; Bourne, Yves; Marchot, Pascale; Chatonnet, Arnaud

    2013-03-25

    Alpha/beta hydrolases function as hydrolases, lyases, transferases, hormone precursors or transporters, chaperones or routers of other proteins. The amount of structural and functional available data related to this protein superfamily expands exponentially, as does the number of proteins classified as alpha/beta hydrolases despite poor sequence similarity and lack of experimental data. However the superfamily can be rationally divided according to sequence or structural homologies, leading to subfamilies of proteins with potentially similar functions. Since the discovery of proteins homologous to cholinesterases but devoid of enzymatic activity (e.g., the neuroligins), divergent functions have been ascribed to members of other subfamilies (e.g., lipases, dipeptidylaminopeptidase IV, etc.). To study the potentially moonlighting properties of alpha/beta hydrolases, the ESTHER database (for ESTerase and alpha/beta Hydrolase Enzymes and Relatives; http://bioweb.ensam.inra.fr/esther), which collects, organizes and disseminates structural and functional information related to alpha/beta hydrolases, has been updated with new tools and the web server interface has been upgraded. A new Overall Table along with a new Tree based on HMM models has been included to tentatively group subfamilies. These tools provide starting points for phylogenetic studies aimed at pinpointing the origin of duplications leading to paralogous genes (e.g., acetylcholinesterase versus butyrylcholinesterase, or neuroligin versus carboxylesterase). Another of our goals is to implement new tools to distinguish catalytically active enzymes from non-catalytic proteins in poorly studied or annotated subfamilies.

  14. THE GRK4 SUBFAMILY OF G PROTEIN-COUPLED RECEPTOR KINASES: ALTERNATIVE SPLICING, GENE ORGANIZATION, AND SEQUENCE CONSERVATION

    Science.gov (United States)

    The GRK4 subfamily of G protein-coupled receptor kinases. Alternative splicing, gene organization, and sequence conservation.Premont RT, Macrae AD, Aparicio SA, Kendall HE, Welch JE, Lefkowitz RJ.Department of Medicine, Howard Hughes Medical Institute, Duke Univer...

  15. Taxonomic study on the family Mitridae (Mollusca: Gastropoda: Neogastropoda) from the China's seas. Subfamilies: Imbricariinae and Cylindromitrinae

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    Ninteen species of subfamilies Imbricariinae and Cylindromitrinae, family Mitridae, are recorded from the China's seas. Of which, one genus and six species are recorded for the first time from China' s seas, i.e., genus Ziba Adams H and Adams A, Cancilla (Cancilla)carnicolor, Ziba duplilirata, Z. insculpta, Neocancilla circula, Scabricola (Scabricola) desetangsii, Scabricola (Swainsonia) ocellata ocellata.

  16. ROLE OF ATP BINDING CASSETTE SUB-FAMILY MEMBER 2 (ABCG2) IN MOUSE EMBRYONIC STEM CELL DEVELOPMENT.

    Science.gov (United States)

    ATP binding cassette sub-family member 2 (ABCG2), is a member of the ABC transporter superfamily and a principal xenobiotic transporter. ABCG2 is also highly expressed in certain stem cell populations where it is thought to be related to stem cell plasticity, although the role o...

  17. Highly conserved salt bridge stabilizes a proteinase K subfamily enzyme, Aqualysin I, from Thermus aquaticus YT-1.

    Science.gov (United States)

    Sakaguchi, Masayoshi; Osaku, Kanae; Maejima, Susumu; Ohno, Nao; Sugahara, Yasusato; Oyama, Fumitaka; Kawakita, Masao

    2014-01-01

    The proteinase K subfamily enzymes, thermophilic Aqualysin I (AQN) from Thermus aquaticus YT-1 and psychrophilic serine protease (VPR) from Vibrio sp. PA-44, have six and seven salt bridges, respectively. To understand the possible significance of salt bridges in the thermal stability of AQN, we prepared mutant proteins in which amino acid residues participating in salt bridges common to proteinase K subfamily members and intrinsic to AQN were replaced to disrupt the bridges one at a time. Disruption of a salt bridge common to proteinase K subfamily enzymes in the D183N mutant resulted in a significant reduction in thermal stability, and a massive change in the content of the secondary structure was observed, even at 70°C, in the circular dichroism (CD) analysis. These results indicate that the common salt bridge Asp183-Arg12 is important in maintaining the conformation of proteinase K subfamily enzymes and suggest the importance of proximity between the regions around Asp183 and the N-terminal region around Arg12. Of the three mutants that lack an AQN intrinsic salt bridge, D212N was more prone to unfolding at 80°C than the wild-type enzyme. Similarly, D17N and E237Q were less thermostable than the wild-type enzyme, although this may be partially due to increased autolysis. The AQN intrinsic salt bridges appear to confer additional thermal stability to this enzyme. These findings will further our understanding of the factors involved in stabilizing protein structure.

  18. Whole genome identification, phylogeny and evolution of the cytochrome P450 family 2 (CYP2) sub-families in birds

    DEFF Research Database (Denmark)

    Almeida, Daniela; Maldonado, Emanuel; Khan, Imran

    2016-01-01

    The cytochrome P450 (CYP) superfamily defends organisms from endogenous and noxious environmental compounds, and thus is crucial for survival. However, beyond mammals the molecular evolution of CYP2 subfamilies is poorly understood. Here, we characterized the CYP2 family across 48 novel avian whole...

  19. Three new species in the subfamily Eriopeltinae Sulc from Italy (Hemiptera, Coccoidea, Coccidae) with comments on the genus Lecanopsis.

    Science.gov (United States)

    Pellizzari, Giuseppina

    2013-01-01

    Three new coccid species, namely Hadzibejliaspis ferenci Pellizzari n. sp., Lecanopsis sicula Pellizzari n. sp. and L. salvatorei Pellizzari n. sp. are described and illustrated. Identification keys for the genera in the subfamily Eriopeltinae Sulc and to species in the genera Hadzibejliaspis Koteja and Lecanopsis Targioni Tozzetti are provided.

  20. Sea snakes in Australian waters (Serpentes: subfamilies Hydrophiinae and Laticaudinae)—a review with an updated identification key

    DEFF Research Database (Denmark)

    Redsted Rasmussen, Arne; Sanders, Kate Laura; Guinea, Michael L

    2014-01-01

    Sea snakes (Elapidae, subfamilies Hydrophiinae and Laticaudinae) reach high species richness in the South China Sea and in the Australian region; however, most countries in the two regions still lack up-to-date checklists and identification tools for these snakes. We present an updated reviewed...

  1. A Suggested New Bacteriophage Genus, “Kp34likevirus”, within the Autographivirinae Subfamily of Podoviridae

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    Harald Eriksson

    2015-04-01

    Full Text Available Klebsiella pneumoniae phages vB_KpnP_SU503 (SU503 and vB_KpnP_SU552A (SU552A are virulent viruses belonging to the Autographivirinae subfamily of Podoviridae that infect and kill multi-resistant K. pneumoniae isolates. Phages SU503 and SU552A show high pairwise nucleotide identity to Klebsiella phages KP34 (NC_013649, F19 (NC_023567 and NTUH-K2044-K1-1 (NC_025418. Bioinformatic analysis of these phage genomes show high conservation of gene arrangement and gene content, conserved catalytically active residues of their RNA polymerase, a common and specific lysis cassette, and form a joint cluster in phylogenetic analysis of their conserved genes. Also, we have performed biological characterization of the burst size, latent period, host specificity (together with KP34 and NTUH-K2044-K1-1, morphology, and structural genes as well as sensitivity testing to various conditions. Based on the analyses of these phages, the creation of a new phage genus is suggested within the Autographivirinae, called “Kp34likevirus” after their type phage, KP34. This genus should encompass the recently genome sequenced Klebsiella phages KP34, SU503, SU552A, F19 and NTUH-K2044-K1-1.

  2. Biodiversity of Food Species of the Solanaceae Family: A Preliminary Taxonomic Inventory of Subfamily Solanoideae

    Directory of Open Access Journals (Sweden)

    John Samuels

    2015-05-01

    Full Text Available Over the last fifty years there has been a continual reduction in horticultural and agricultural biodiversity of nutritionally important plants, including those of the Solanaceae family. To add to this, the broad range of traditional crops, previously grown on a sustainable scale in some parts of the world, has been replaced by a narrow range of major crops grown as large-scale monocultures. In order to counteract this trend, and to help maintain a broad wealth of genetic resources, conservation is essential. This, in turn, helps to safeguard food security. A taxonomic inventory, covering the diversity of species in a plant group, is an important first step in conservation. The Solanaceae is one of the major plant families providing food species. A survey of the biodiversity, ethnobotany and taxonomy of subfamily Solanoideae was undertaken and is presented here as an inventory of food species. Fifteen genera provide species that are utilised for food across the world. Of these, only four genera contain economically significant cultivated food cropspecies. The majority of these are in the genus Solanum, whilst Capsicum, Physalis and Lycium contribute the remainder of cultivated crop species. These genera and others also comprise species that are semi-cultivated, tolerated as useful weeds, or gathered from the wild.

  3. A review of the subfamily Picobiinae Johnston and Kethley, 1973 (Acariformes: Prostigmata: Syringophilidae).

    Science.gov (United States)

    Skoracki, Maciej; Sikora, Bozena; Spicer, Greg S

    2016-05-19

    The fauna of quill mites of the subfamily Picobiinae Johnston and Kethley, 1973 (Acariformes: Cheyletoidea: Syringophilidae) is comprehensively revised. All of 78 known species, which are grouped into 11 genera, are examined and diagnosed or redescribed. Data on picobiine hosts and distribution are summarized, including new host and locality records. The following new species are described: Charadriineopicobia apricaria sp. nov. ex Pluvialis apricaria (Linnaeus) (Charadriiformes: Charadriidae) from France, Neopicobia pari sp. nov. ex Periparus venustulus Swinhoe (type host) (Passeriformes: Paridae) from China, Parus major Linnaeus (Paridae) from Macedonia and Finland, and Poecile varius Temminck and Schlegel (Paridae) from Japan, Picobia magellani sp. nov. ex Scytalopus magellanicus (Gmelin) (Passeriformes: Rhinocryptidae) from Colombia, Picobia lonchura sp. nov. ex Lonchura leucogastra (Blyth) (Passeriformes: Estrildidae) from Indonesia, Picobia makoli sp. nov. ex Xiphocolaptes promeropirhynchus (Lesson) (Passeriformes: Furnariidae) from Colombia. The species Picobia polonica Skoracki, Magowski and Dabert, 2001 syn. nov. is a junior synonym of C. khulkhaskhani Kivganov and Sharafat, 1995. The following new combinations are proposed: Neopicobia ictericus (Skoracki and Glowska, 2010) comb. nov., Rafapicobia brotogeris (Fain, Bochkov and Mironov, 2000) comb. nov., and Rafapicobia ramphastos (Fain, Bochkov and Mironov, 2000) comb. nov. Keys to the all picobiine genera and species are presented, along with a check-list of picobiine species and their hosts.

  4. The exodus subfamily of CC chemokines inhibits the proliferation of chronic myelogenous leukemia progenitors.

    Science.gov (United States)

    Hromas, R; Cripe, L; Hangoc, G; Cooper, S; Broxmeyer, H E

    2000-02-15

    Chemokines are a family of related proteins that regulate leukocyte infiltration into inflamed tissue and play important roles in disease processes. Among the biologic activities of chemokines is inhibition of proliferation of normal hematopoietic progenitors. However, chemokines that inhibit normal progenitors rarely inhibit proliferation of hematopoietic progenitors from patients with chronic myelogenous leukemia (CML). We and others recently cloned a subfamily of CC chemokines that share similar amino-terminal peptide sequences and a remarkable ability to chemoattract T cells. These chemokines, Exodus-1/LARC/MIP-3alpha, Exodus-2/SLC/6Ckine/TCA4, and Exodus-3/CKbeta11/MIP-3beta, were found to inhibit proliferation of normal human marrow progenitors. The study described here found that these chemokines also inhibited the proliferation of progenitors in every sample of marrow from patients with CML that was tested. This demonstration of consistent inhibition of CML progenitor proliferation makes the 3 Exodus chemokines unique among chemokines. (Blood. 2000;95:1506-1508)

  5. Identification of the Alternative Promoters of the KChIP4 Subfamily

    Institute of Scientific and Technical Information of China (English)

    Xiao-Yun DENG; Jia-Hui XIA; Fang CAI; Kun XIA; Qian PAN; Zhi-Gao LONG; Ling-Qian WU; De-Sheng LIANG; He-Ping DAI; Zhuo-Hua ZHANG

    2005-01-01

    The subfamily of voltage-dependent potassium (Kv) channel interacting protein 4 (KChIP4)is made up of the auxiliary interacting protein of voltage-dependent potassium channels. In this study, the structure of four splicing variants of the human KChIP4 gene was analyzed. Three of the four isoforms of the KChIP4 gene, KChIP4.1, KChIP4.2 and KChIP4.4, were amplified from mouse and human fetal brain tissues by reverse transcription-polymerase chain reaction and then identified. Based on the bioinformatics analysis of the genomic sequences of the gene, we cloned and characterized two promoter fragments from the KChIP4 gene. One was a 325 bp fragment upstream of the 5' end of the KChIP4.1 mRNA sequence and the other was an 818 bp fragment located immediately at the 5' end of the KChIP4.4 variant. Both of them can initiate the transcription of the reporter gene in HT1080 cells and Sprague-Dawley (SD) rat fetal brain neurons, and they contain C+G islands, except typical TATA boxes and CAAT boxes. This shows that the KChIP4 gene expression is regulated by an alternative promoter.

  6. Molecular phylogeny and biogeography of the weevil subfamily Platypodinae reveals evolutionarily conserved range patterns.

    Science.gov (United States)

    Jordal, Bjarte H

    2015-11-01

    Platypodinae is a peculiar weevil subfamily of species that cultivate fungi in tunnels excavated in dead wood. Their geographical distribution is generally restricted, with genera confined to a single continent or large island, which provides a useful system for biogeographical research. This study establishes the first detailed molecular phylogeny of the group, with the aim of testing hypotheses on classification, diversification, and biogeography. A phylogeny was reconstructed based on 3648 nucleotides from COI, EF-1α, CAD, ArgK, and 28S. Tree topology was well resolved and indicated a strong correlation with geography, more so than predicted by previous morphology-based classifications. Tesserocerini was paraphyletic, with Notoplatypus as the sister group to a clade consisting of three main lineages of Tesserocerini and the recently evolved Platypodini. Austroplatypus formed the sister group to all remaining Platypodini and hence confirmed its separate status from Platypus. The Indo-Australian genera of Platypodini were strikingly paraphyletic, suggesting that the taxonomy of this tribe needs careful revision. Ancestral-area reconstructions in Lagrange and S-DIVA were ambiguous for nodes roughly older than 80 Ma. More recent events were firmly assessed and involved post-Gondwanan long-distance dispersal. The Neotropics was colonized three times, all from the Afrotropical region, with the latest event less than 25 Ma that included the ancestor of all Neotropical Platypodini.

  7. Adaptive evolution after gene duplication in alpha-KT x 14 subfamily from Buthus martensii Karsch.

    Science.gov (United States)

    Cao, Zhijian; Mao, Xin; Xu, Xiuling; Sheng, Jiqun; Dai, Chao; Wu, Yingliang; Luo, Feng; Sha, Yonggang; Jiang, Dahe; Li, Wenxin

    2005-07-01

    A series of isoforms of alpha-KT x 14 (short chain potassium channel scorpion toxins) were isolated from the venom of Buthus martensii Karsch by RACE and screening cDNA library methods. These isoforms adding BmKK1--3 and BmSKTx1--2 together shared high homology (more than 97%) with each other. The result of genomic sequence analysis showed that a length 79 bp intron is inserted Ala codes between the first and the second base at the 17th amino acid of signal peptide. The introns of these isoforms also share high homology with those of BmKK2 and BmSKT x 1 reported previously. Sequence analysis of many clones of cDNA and genomic DNA showed that a species population or individual polymorphism of alpha-KT x 14 genes took place in scorpion Buthus martensii Karsch and accelerated evolution played an important role in the forming process of alpha-KT x 14 scorpion toxins subfamily. The result of southern hybridization indicated that alpha-KT x 14 toxin genes existed in scorpion chromosome with multicopies. All findings maybe provided an important evidence for an extensive evolutionary process of the scorpion "pharmacological factory": at the early course of evolution, the ancestor toxic gene duplicated into a series of multicopy genes integrated at the different chromosome; at the late course of evolution, subsequent functional divergence of duplicate genes was generated by mutations, deletions and insertion.

  8. Cytogenetic analysis of five species of the subfamily Corydoradinae (Teleostei: Siluriformes: Callichthyidae

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    Cristiane Kioko Shimabukuro-Dias

    2004-01-01

    Full Text Available In the present study, five callichthyid species belonging to the subfamily Corydoradinae were karyotyped: three species of Aspidoras and two of Corydoras. The three species of Aspidoras had the same diploid number, 2n = 46 chromosomes, similar karyotypic formulae, with most chromosomes metacentric or submetacentric, single interstitial Ag-NORs and C-band positive segments mainly found in the centromeric position. The comparative analysis of cytogenetic data available for the genus Aspidoras and other species of Corydoradinae suggest that several events of centric fusion occurred in the origin of the species of Aspidoras. The two analyzed species of Corydoras showed high diploid numbers, 2n = 74 in C. sodalis and 2n = 90 in C. britskii. While C. sodalis exhibited single Ag-NORs and terminal, interstitial and centromeric C-band positive segments in almost all chromosomes, C. britskii showed multiple Ag-NORs and a small number of C-band positive segments found in the terminal position in one acrocentric (A pair and in the interstitial position in one subtelocentric (ST pair. The occurrence of high diploid numbers and many ST and A chromosomes are uncommon among the Corydoradinae, suggesting the occurrence of a high number of chromosome rearrangements, mainly centric fissions, in the origin of the Corydoras species studied.

  9. Contribution of transient receptor potential vanilloid subfamily 1 to endothelin-1-induced thermal hyperalgesia.

    Science.gov (United States)

    Kawamata, T; Ji, W; Yamamoto, J; Niiyama, Y; Furuse, S; Namiki, A

    2008-06-26

    Endothelin-1 (ET-1) plays an important role in peripheral pain processing. However, the mechanisms of the nociceptive action of ET-1 have not been fully elucidated. In this study, we investigated the contribution of transient receptor potential vanilloid subfamily 1 (TRPV1) to ET-1-induced thermal hyperalgesia. Intraplantar ET-1-induced thermal hyperalgesia was examined by assessing the paw withdrawal latency to noxious heat stimuli. In electrophysiological study, whole-cell patch-clamp recordings were performed to investigate the interaction of ET-1 and TRPV1 using human embryonic kidney 293 (HEK293) cells expressing endothelin type A receptor (ET(A)) and TRPV1. Intraplantar ET-1 (3, 10 and 30 pmol) produced thermal hyperalgesia in a dose-dependent manner. Thermal hyperalgesia was attenuated by the inhibition of ET(A) and protein kinase C (PKC) but not that of ET(B). ET-1-induced thermal hyperalgesia was significantly attenuated in TRPV1-deficient mice compared with that in wild-type mice. In voltage-clamp experiments, 10 nM capsaicin evoked small inward currents in HEK293 cells expressing TRPV1 and ET(A). In the presence of ET-1, capsaicin produced much larger current responses (Pthermal hyperalgesia.

  10. Modulation of the Rat Hepatic Cytochrome P4501A Subfamily Using Biotin Supplementation

    Directory of Open Access Journals (Sweden)

    M. D. Ronquillo-Sánchez

    2013-01-01

    Full Text Available Studies have found that biotin favors glucose and lipid metabolism, and medications containing biotin have been developed. Despite the use of biotin as a pharmacological agent, few studies have addressed toxicity aspects including the possible interaction with cytochrome P450 enzyme family. This study analyzed the effects of pharmacological doses of biotin on the expression and activity of the cytochrome P4501A subfamily involved in the metabolism of xenobiotics. Wistar rats were treated daily with biotin (2 mg/kg, i.p., while the control groups were treated with saline. All of the rats were sacrificed by cervical dislocation after 1, 3, 5, or 7 days of treatment. CYP1A1 and CYP1A2 mRNAs were modified by biotin while enzyme activity and protein concentration were not affected. The lack of an effect of biotin on CYP1A activity was confirmed using other experimental strategies, including (i cotreatment of the animals with biotin and a known CYP1A inducer; (ii the addition of biotin to the reaction mixtures for the measurement of CYP1A1 and CYP1A2 activities; and (iii the use of an S9 mixture that was prepared from control and biotin-treated rats to analyze the activation of benzo[a]pyrene (BaP into mutagenic metabolites using the Ames test. The results suggest that biotin does not influence the CYP1A-mediated metabolism of xenobiotics.

  11. Out of Africa:Miocene Dispersal, Vicariance, and Extinction within Hyacinthaceae Subfamily Urgineoideae

    Institute of Scientific and Technical Information of China (English)

    Syed Shujait Ali; Martin Pfosser; Wolfgang Wetschnig; Mario MartnezAzorn; Manuel B. Crespo; Yan Yu

    2013-01-01

    Disjunct distribution patterns in plant lineages are usually explained according to three hypotheses:vicariance, geodispersal, and long-distance dispersal. The role of these hypotheses is tested in Urgineoideae (Hyacinthaceae), a subfamily disjunctly distributed in Africa, Madagascar, India, and the Mediterranean region. The potential ancestral range, dispersal routes, and factors responsible for the current distribution in Urgineoideae are investigated using divergence time estimations. Urgineoideae originated in Southern Africa approximately 48.9 Mya. Two independent dispersal events in the Western Mediterranean region possibly occurred during Early Oligocene and Miocene (29.9-8.5 Mya) via Eastern and Northwestern Africa. A dispersal from Northwestern Africa to India could have occurred between 16.3 and 7.6 Mya. Vicariance and extinction events occurred approximately 21.6 Mya. Colonization of Madagascar occurred between 30.6 and 16.6 Mya, after a single transoceanic dispersal event from Southern Africa. The current disjunct distributions of Urgineoideae are not satisfactorily explained by Gondwana fragmentation or dispersal via boreotropical forests, due to the younger divergence time estimates. The flattened winged seeds of Urgineoideae could have played an important role in long-distance dispersal by strong winds and big storms, whereas geodispersal could have also occurred from Southern Africa to Asia and the Mediterranean region via the so-called arid and high-altitude corridors.

  12. Observation on the head and chemoreceptors of Maruca vitrata(Lepidoptera:Crambidae)larvae%豇豆荚螟幼虫头部形态及化学感受器观察

    Institute of Scientific and Technical Information of China (English)

    王攀; 郑霞林; 雷朝亮; 王小平

    2011-01-01

    [目的]了解豇豆英螟(Maruca vitrata)幼虫头部感受器的形态、数量和分布,为探讨其功能和感应机制提供依据.[方法]利用扫描电镜对豇豆英螟5龄幼虫的头部以及触角和口器上的化学感受器进行扫描观察并描述.[结果]豇豆英螟幼虫的头式为下口式;头上具有单眼、触角、感觉刚毛、上唇、上颚、下颚、下唇、吐丝器;幼虫的触角上存在检形、锥形和毛形3种感受器;口器附肢下颚须上有8个锥形感受器;下唇须在第2、3节上各着生有1个锥形感受器.[结论]豇豆英螟幼虫头部共有4种类型的感受器:毛形感受器(Str)、锥形感受器(Sb)、小锥形感受器(Sbs)和栓形感受器(Ss),各自担负着不同的功能.%[Objective]The morphology, amount and distribution of chemoreceptors on the head of Maruca vitrata (Fabricius) were observed, which will provide a basis for its functional and mechanical research.[Method]The chemoreceptors on antennae and mouthparts of the 5th instar larvae of M.vitrata were observed with scanning electron microscopy.[Result]The head structure type of the larvae was hypognathous.Three kinds of chemoreceptors were found on antennae of the larvae, namely sensilla styloconicum, sensilla basiconica and sensilla trichodea.The mouthparts bears plenty of hemoreceptors, especially on gelea and maxillary palpus of maxilla.The maxillary palpus of mouthparts appendages had eight kinds of sensilla basiconica, and one kind of sensilla basiconica was also observed on the second and third segments of labial palpus respectively.[Conclusion]There are four types of chemoreceptors on the head of M.vitrata larvae, named sensilla trichodea, sensilla basiconica, small sensilla basiconica and sensilla styloconicum with different functions.

  13. Aepyosciurinae -- a new subfamily of Sciuridae (Rodentia, Mammalia) from basal loess deposits at the northeastern border of Tibetan Plateau

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    Aepyosciurinae, a new subfamily of Sciuridae, were found at the base of the early Pleistocene loess deposits in Dongxiang County, Gansu Province. Its unilaterally hypsodont and lophodont cheek teeth are unique among the sciurids so far known all over the world. Certain degree of similarity can be observed between the cheek teeth of the new subfamily and the Anomalurinae living in tropical and subtropical forests in central and western Africa. Aepyosciuris orientalis gen. et sp. nov. might have lived in montaneous woodland or grassland and lived on harder leaves, barks, or even grass. This tends to show that the northeastern border area of the Tibetan Plateau had been lifted considerably high in early Pleistocene (ca. 2 Ma), with drier climate, becoming a suitable habitat for Aepyosciurus orientalis.

  14. RINL, guanine nucleotide exchange factor Rab5-subfamily, is involved in the EphA8-degradation pathway with odin.

    Directory of Open Access Journals (Sweden)

    Hiroaki Kajiho

    Full Text Available The Rab family of small guanosine triphosphatases (GTPases plays a vital role in membrane trafficking. Its active GTP-bound state is driven by guanine nucleotide-exchange factors (GEFs. Ras and Rab interactor (or Ras interaction/interference-like (RINL, which contains a conserved VPS9 domain critical for GEF action, was recently identified as a new Rab5 subfamily GEF in vitro. However, its detailed function and interacting molecules have not yet been fully elucidated. Here we found that RINL has GEF activity for the Rab5 subfamily proteins by measuring their GTP-bound forms in cultured cells. We also found that RINL interacts with odin, a member of the ankyrin-repeat and sterile-alpha motif (SAM domain-containing (Anks protein family. In addition, the Eph tyrosine kinase receptor EphA8 formed a ternary complex with both RINL and odin. Interestingly, RINL expression in cultured cells reduced EphA8 levels in a manner dependent on both its GEF activity and interaction with odin. In addition, knockdown of RINL increased EphA8 level in HeLa cells. Our findings suggest that RINL, as a GEF for Rab5 subfamily, is implicated in the EphA8-degradation pathway via its interaction with odin.

  15. Type 2 diabetes - Tuberculosis co-morbidity is associated with diminished circulating levels of IL-20 subfamily of cytokines.

    Science.gov (United States)

    Kumar, Nathella Pavan; Banurekha, Vaithilingam V; Nair, Dina; Kumaran, Paul; Dolla, Chandra Kumar; Babu, Subash

    2015-12-01

    IL-20 subfamily of cytokines play an important role in both host defense mechanisms and glucose metabolism. Since, the interaction between tuberculosis (TB) and diabetes (DM) involves both of the above processes, we examined the association of IL-20 subfamily of cytokines in TB-DM co-morbidity. We examined circulating plasma cytokine levels in individuals with active TB with (PTB-DM) or without (PTB) diabetes and also those with latent TB with (LTB-DM) or without (LTB) diabetes. PTB-DM is characterized by diminished circulating levels of IL-19, IL-20, IL-22 and IL-24 but increased levels of IL-10. Similarly, LTB-DM was also characterized by diminished circulating levels of IL-10, IL-19, IL-20 and IL-24 but increased levels of IL-22. Moreover, there was a significant negative correlation of IL-10, IL-19, IL-20, IL-22 and IL-24 levels with hemoglobin A1C (HbA1c) levels in both PTB and/or LTB individuals. Finally, PTB is characterized by diminished levels of IL-19, IL-20, IL-22 and IL-24 in comparison to LTB individuals. Our data reveal that coincident diabetes in either PTB or LTB is characterized by decreased production of the IL-20 subfamily of cytokines and suggest that these cytokines might play an important role in pathogenesis or protection.

  16. Evolutionary relationships among primary endosymbionts of the mealybug subfamily phenacoccinae (hemiptera: Coccoidea: Pseudococcidae).

    Science.gov (United States)

    Gruwell, Matthew E; Hardy, Nate B; Gullan, Penny J; Dittmar, Katharina

    2010-11-01

    Mealybugs (Coccoidea: Pseudococcidae) are sap-sucking plant parasites that harbor bacterial endosymbionts within specialized organs. Previous studies have identified two subfamilies, Pseudococcinae and Phenacoccinae, within mealybugs and determined the primary endosymbionts (P-endosymbionts) of the Pseudococcinae to be Betaproteobacteria ("Candidatus Tremblaya princeps") containing Gammaproteobacteria secondary symbionts. Here, the P-endosymbionts of phenacoccine mealybugs are characterized based on 16S rRNA from the bacteria of 20 species of phenacoccine mealybugs and four outgroup Puto species (Coccoidea: Putoidae) and aligned to more than 100 published 16S rRNA sequences from symbiotic and free-living bacteria. Phylogenetic analyses recovered three separate lineages of bacteria from the Phenacoccinae, and these are considered to be the P-endosymbionts of their respective mealybug hosts, with those from (i) the mealybug genus Rastrococcus belonging to the Bacteroidetes, (ii) the subterranean mealybugs, tribe Rhizoecini, also within Bacteroidetes, in a clade sister to cockroach endosymbionts (Blattabacterium), and (iii) the remaining Phenacoccinae within the Betaproteobacteria, forming a well-supported sister group to "Candidatus Tremblaya princeps." Names are proposed for two strongly supported lineages: "Candidatus Brownia rhizoecola" for P-endosymbionts of Rhizoecini and "Candidatus Tremblaya phenacola" for P-endosymbionts of Phenacoccinae excluding Rastrococcus and Rhizoecini. Rates of nucleotide substitution among lineages of Tremblaya were inferred to be significantly faster than those of free-living Betaproteobacteria. Analyses also recovered a clade of Gammaproteobacteria, sister to the P-endosymbiont lineage of aphids ("Candidatus Buchnera aphidicola"), containing the endosymbionts of Putoidae, the secondary endosymbionts of pseudococcine mealybugs, and the endosymbionts of several other insect groups.

  17. Comparative genome analysis between Agrostis stolonifera and members of the Pooideae subfamily, including Brachypodium distachyon.

    Directory of Open Access Journals (Sweden)

    Loreto Araneda

    Full Text Available Creeping bentgrass (Agrostis stolonifera, allotetraploid 2n = 4x = 28 is one of the major cool-season turfgrasses. It is widely used on golf courses due to its tolerance to low mowing and aggressive growth habit. In this study, we investigated genome relationships of creeping bentgrass relative to the Triticeae (a consensus map of Triticum aestivum, T. tauschii, Hordeum vulgare, and H. spontaneum, oat, rice, and ryegrass maps using a common set of 229 EST-RFLP markers. The genome comparisons based on the RFLP markers revealed large-scale chromosomal rearrangements on different numbers of linkage groups (LGs of creeping bentgrass relative to the Triticeae (3 LGs, oat (4 LGs, and rice (8 LGs. However, we detected no chromosomal rearrangement between creeping bentgrass and ryegrass, suggesting that these recently domesticated species might be closely related, despite their memberships to different Pooideae tribes. In addition, the genome of creeping bentgrass was compared with the complete genome sequence of Brachypodium distachyon in Pooideae subfamily using both sequences of the above-mentioned mapped EST-RFLP markers and sequences of 8,470 publicly available A. stolonifera ESTs (AgEST. We discovered large-scale chromosomal rearrangements on six LGs of creeping bentgrass relative to B. distachyon. Also, a total of 24 syntenic blocks based on 678 orthologus loci were identified between these two grass species. The EST orthologs can be utilized in further comparative mapping of Pooideae species. These results will be useful for genetic improvement of Agrostis species and will provide a better understanding of evolution within Pooideae species.

  18. The Crystal Structure of Streptococcus pyogenes Uridine Phosphorylase Reveals a Distinct Subfamily of Nucleoside Phosphorylases

    Energy Technology Data Exchange (ETDEWEB)

    Tran, Timothy H.; Christoffersen, S.; Allan, Paula W.; Parker, William B.; Piskur, Jure; Serra, I.; Terreni, M.; Ealick, Steven E. (Cornell); (Pavia); (Lund); (Southern Research)

    2011-09-20

    Uridine phosphorylase (UP), a key enzyme in the pyrimidine salvage pathway, catalyzes the reversible phosphorolysis of uridine or 2'-deoxyuridine to uracil and ribose 1-phosphate or 2'-deoxyribose 1-phosphate. This enzyme belongs to the nucleoside phosphorylase I superfamily whose members show diverse specificity for nucleoside substrates. Phylogenetic analysis shows Streptococcus pyogenes uridine phosphorylase (SpUP) is found in a distinct branch of the pyrimidine subfamily of nucleoside phosphorylases. To further characterize SpUP, we determined the crystal structure in complex with the products, ribose 1-phosphate and uracil, at 1.8 {angstrom} resolution. Like Escherichia coli UP (EcUP), the biological unit of SpUP is a hexamer with an ?/? monomeric fold. A novel feature of the active site is the presence of His169, which structurally aligns with Arg168 of the EcUP structure. A second active site residue, Lys162, is not present in previously determined UP structures and interacts with O2 of uracil. Biochemical studies of wild-type SpUP showed that its substrate specificity is similar to that of EcUP, while EcUP is {approx}7-fold more efficient than SpUP. Biochemical studies of SpUP mutants showed that mutations of His169 reduced activity, while mutation of Lys162 abolished all activity, suggesting that the negative charge in the transition state resides mostly on uracil O2. This is in contrast to EcUP for which transition state stabilization occurs mostly at O4.

  19. Cephalocteinae Mulsant et Rey, 1866 (Hemiptera, Heteroptera), a subfamily of Cydnidae new for the Italian fauna: first record of Cephalocteus scarabaeoides (Fabricius, 1807) from Sardinia.

    Science.gov (United States)

    Fancello, Luca; Cillo, Davide; Bazzato, Erika

    2016-01-25

    Cephalocteus scarabaeoides is recorded from the south-western coast of Sardinia, in sandy habitat (marine dunes near the beach), for the first time. The species and the subfamily are new for the Italian fauna.

  20. Members of rice plasma membrane intrinsic proteins subfamily are involved in arsenite permeability and tolerance in plants.

    Science.gov (United States)

    Mosa, Kareem A; Kumar, Kundan; Chhikara, Sudesh; Mcdermott, Joseph; Liu, Zijuan; Musante, Craig; White, Jason C; Dhankher, Om Parkash

    2012-12-01

    Rice accumulates high level of arsenic (As) in its edible parts and thus plays an important role in the transfer of As into the food chain. However, the mechanisms of As uptake and its detoxification in rice are not well understood. Recently, members of the Nodulin 26-like intrinsic protein (NIP) subfamily of plant aquaporins were shown to transport arsenite in rice and Arabidopsis. Here we report that members of the rice plasma membrane intrinsic protein (PIP) subfamily are also involved in As tolerance and transport. Based on the homology search with the mammalian AQP9 and yeast Fps1 arsenite transporters, we identified and cloned five rice PIP gene subfamily members. qRT-PCR analysis of PIPs in rice root and shoot tissues revealed a significant down regulation of transcripts encoding OsPIP1;2, OsPIP1;3, OsPIP2;4, OsPIP2;6, and OsPIP2;7 in response to arsenite treatment. Heterologous expression of OsPIP2;4, OsPIP2;6, and OsPIP2;7 in Xenopus laevis oocytes significantly increased the uptake of arsenite. Overexpression of OsPIP2;4, OsPIP2;6, and OsPIP2;7 in Arabidopsis yielded enhanced arsenite tolerance and higher biomass accumulation. Further, these transgenic plants showed no significant accumulation of As in shoot and root tissues in long term uptake assays. Whereas, short duration exposure to arsenite caused both active influx and efflux of As in the roots. The data suggests a bidirectional arsenite permeability of rice PIPs in plants. These rice PIPs genes will be highly useful for engineering important food and biofuel crops for enhanced crop productivity on contaminated soils without increasing the accumulation of toxic As in the biomass or edible tissues.

  1. Whole genome identification, phylogeny and evolution of the cytochrome P450 family 2 (CYP2) sub-families in birds

    DEFF Research Database (Denmark)

    Almeida, Daniela; Maldonado, Emanuel; Khan, Imran;

    2016-01-01

    The cytochrome P450 (CYP) superfamily defends organisms from endogenous and noxious environmental compounds, and thus is crucial for survival. However, beyond mammals the molecular evolution of CYP2 subfamilies is poorly understood. Here, we characterized the CYP2 family across 48 novel avian whole......0, SRS2_SRS3 and SRS3.1) and heme binding areas that influence CYP2 structure and function of functional importance as under significant positive selection. Some of the positively selected sites in avian CYP2D are located within the same SRS1 region that was previously linked with the metabolism...

  2. Sea snakes in Australian waters (Serpentes: subfamilies Hydrophiinae and Laticaudinae)--a review with an updated identification key.

    Science.gov (United States)

    Rasmussen, Arne Redsted; Sanders, Kate Laura; Guinea, Michael L; Amey, Andrew P

    2014-10-02

    Sea snakes (Elapidae, subfamilies Hydrophiinae and Laticaudinae) reach high species richness in the South China Sea and in the Australian region; however, most countries in the two regions still lack up-to-date checklists and identification tools for these snakes. We present an updated reviewed checklist and a new complete identification key to sea snakes in Australian waters. The identification key includes 29 species documented and 4 possibly occurring taxa and is based mostly on easy-to-use external characters. We find no evidence for breeding populations of Laticauda in Australian waters, but include the genus on the list of possibly occurring taxa. 

  3. Evolution of substrate recognition sites (SRSs) in cytochromes P450 from Apiaceae exemplified by the CYP71AJ subfamily

    DEFF Research Database (Denmark)

    Dueholm, Bjørn; Krieger, Celia; Drew, Damian;

    2015-01-01

    Background: Large proliferations of cytochrome P450 encoding genes resulting from gene duplications can be termed as 'blooms', providing genetic material for the genesis and evolution of biosynthetic pathways. Furanocoumarins are allelochemicals produced by many of the species in Apiaceaous plants...... and four other subclades were identified and shown to be part of two distinct clades within the CYP71AJ subfamily. The subclades show significant variability within their substrate recognition sites between the clades, suggesting different biochemical functions and providing insights into the evolution...

  4. New species and records of the mite genus Prolistrophorus (Acariformes: Listrophoridae) from rodents of the subfamily Sigmodontinae (Rodentia: Cricetidae).

    Science.gov (United States)

    Bochkov, Andre V; Lareschi, Marcela; Barreto, Mauricio

    2014-10-01

    Six fur-mite species of the genus Prolistrophorus Fain, 1970 (Acariformes: Listrophoridae) were recorded from Central and South American rodents of the subfamily Sigmodontinae (Rodentia: Cricetidae). Among them, Prolistrophorus (Aprolistrophorus) parabidentatus sp. nov. from Akodon azarae from Argentina and Prolistrophorus (Aprolistrophorus) tylomys sp. nov. from Tylomys nudicaudus from Guatemala are described as new for science. New hosts are recorded for the following species: Prolistrophorus (Prolistrophorus) grassii (Radford, 1954) from Zygodontomys brevicauda from Colombia, P. (P.) frontalis (Hirst, 1921) from Oligoryzomys sp. from Argentina, P. (P.) argentinus (Hirst, 1921) from Melanomys caliginosus, Akodon affinis from Colombia and Scapteromys aquaticus from Argentina, Prolistrophorus (Beprolistrophorus) hirstianus Fain, 1973 from Scapteromys aquaticus from Argentina.

  5. A genomic view of the NOD-like receptor family in teleost fish: Identification of a novel NLR subfamily in zebrafish

    Science.gov (United States)

    Laing, K.J.; Purcell, M.K.; Winton, J.R.; Hansen, J.D.

    2008-01-01

    Background. A large multigene family of NOD-like receptor (NLR) molecules have been described in mammals and implicated in immunity and apoptosis. Little information, however, exists concerning this gene family in non-mammalian taxa. This current study, therefore, provides an in-depth investigation of this gene family in lower vertebrates including extensive phylogenetic comparison of zebrafish NLRs with orthologs in tetrapods, and analysis of their tissue-specific expression. Results. Three distinct NLR subfamilies were identified by mining genome databases of various non-mammalian vertebrates; the first subfamily (NLR-A) resembles mammalian NODs, the second (NLR-B) resembles mammalian NALPs, while the third (NLR-C) appears to be unique to teleost fish. In zebrafish, NLR-A and NLR-B subfamilies contain five and six genes respectively. The third subfamily is large, containing several hundred NLR-C genes, many of which are predicted to encode a C-terminal B30.2 domain. This subfamily most likely evolved from a NOD3-like molecule. Gene predictions for zebrafish NLRs were verified using sequence derived from ESTs or direct sequencing of cDNA. Reverse-transcriptase (RT)-PCR analysis confirmed expression of representative genes from each subfamily in selected tissues. Conclusion. Our findings confirm the presence of multiple NLR gene orthologs, which form a large multigene family in teleostei. Although the functional significance of the three major NLR subfamilies is unclear, we speculate that conservation and abundance of NLR molecules in all teleostei genomes, reflects an essential role in cellular control, apoptosis or immunity throughout bony fish. ?? 2008 Laing et al; licensee BioMed Central Ltd.

  6. A genomic view of the NOD-like receptor family in teleost fish: identification of a novel NLR subfamily in zebrafish

    Directory of Open Access Journals (Sweden)

    Winton James R

    2008-02-01

    Full Text Available Abstract Background A large multigene family of NOD-like receptor (NLR molecules have been described in mammals and implicated in immunity and apoptosis. Little information, however, exists concerning this gene family in non-mammalian taxa. This current study, therefore, provides an in-depth investigation of this gene family in lower vertebrates including extensive phylogenetic comparison of zebrafish NLRs with orthologs in tetrapods, and analysis of their tissue-specific expression. Results Three distinct NLR subfamilies were identified by mining genome databases of various non-mammalian vertebrates; the first subfamily (NLR-A resembles mammalian NODs, the second (NLR-B resembles mammalian NALPs, while the third (NLR-C appears to be unique to teleost fish. In zebrafish, NLR-A and NLR-B subfamilies contain five and six genes respectively. The third subfamily is large, containing several hundred NLR-C genes, many of which are predicted to encode a C-terminal B30.2 domain. This subfamily most likely evolved from a NOD3-like molecule. Gene predictions for zebrafish NLRs were verified using sequence derived from ESTs or direct sequencing of cDNA. Reverse-transcriptase (RT-PCR analysis confirmed expression of representative genes from each subfamily in selected tissues. Conclusion Our findings confirm the presence of multiple NLR gene orthologs, which form a large multigene family in teleostei. Although the functional significance of the three major NLR subfamilies is unclear, we speculate that conservation and abundance of NLR molecules in all teleostei genomes, reflects an essential role in cellular control, apoptosis or immunity throughout bony fish.

  7. Structural and Functional Elucidation of Peptide Ts11 Shows Evidence of a Novel Subfamily of Scorpion Venom Toxins

    Science.gov (United States)

    Cremonez, Caroline M.; Maiti, Mohitosh; Peigneur, Steve; Cassoli, Juliana Silva; Dutra, Alexandre A. A.; Waelkens, Etienne; Lescrinier, Eveline; Herdewijn, Piet; de Lima, Maria Elena; Pimenta, Adriano M. C.; Arantes, Eliane C.; Tytgat, Jan

    2016-01-01

    To date, several families of peptide toxins specifically interacting with ion channels in scorpion venom have been described. One of these families comprise peptide toxins (called KTxs), known to modulate potassium channels. Thus far, 202 KTxs have been reported, belonging to several subfamilies of KTxs (called α, β, γ, κ, δ, and λ-KTxs). Here we report on a previously described orphan toxin from Tityus serrulatus venom, named Ts11. We carried out an in-depth structure-function analysis combining 3D structure elucidation of Ts11 and electrophysiological characterization of the toxin. The Ts11 structure is highlighted by an Inhibitor Cystine Knot (ICK) type scaffold, completely devoid of the classical secondary structure elements (α-helix and/or β-strand). This has, to the best of our knowledge, never been described before for scorpion toxins and therefore represents a novel, 6th type of structural fold for these scorpion peptides. On the basis of their preferred interaction with voltage-gated K channels, as compared to all the other targets tested, it can be postulated that Ts11 is the first member of a new subfamily, designated as ε-KTx. PMID:27706049

  8. Crystal structure of Proteus mirabilis lipase, a novel lipase from the Proteus/psychrophilic subfamily of lipase family I.1.

    Directory of Open Access Journals (Sweden)

    Tyler P Korman

    Full Text Available Bacterial lipases from family I.1 and I.2 catalyze the hydrolysis of triacylglycerol between 25-45°C and are used extensively as biocatalysts. The lipase from Proteus mirabilis belongs to the Proteus/psychrophilic subfamily of lipase family I.1 and is a promising catalyst for biodiesel production because it can tolerate high amounts of water in the reaction. Here we present the crystal structure of the Proteus mirabilis lipase, a member of the Proteus/psychrophilic subfamily of I.1lipases. The structure of the Proteus mirabilis lipase was solved in the absence and presence of a bound phosphonate inhibitor. Unexpectedly, both the apo and inhibitor bound forms of P. mirabilis lipase were found to be in a closed conformation. The structure reveals a unique oxyanion hole and a wide active site that is solvent accessible even in the closed conformation. A distinct mechanism for Ca²⁺ coordination may explain how these lipases can fold without specific chaperones.

  9. Linked 5S and 45S rDNA sites are highly conserved through the subfamily Aurantioideae (Rutaceae).

    Science.gov (United States)

    Barros E Silva, A E; Dos Santos Soares Filho, W; Guerra, M

    2013-01-01

    Sites of 5S and 45S rDNA are more commonly located on different chromosomes of most angiosperms. Previous investigations have shown that in the subfamily Aurantioideae these sites may appear closely linked (adjacent sites), as in Poncirustrifoliata, or completely isolated, as in some species of Citrus. In the present work, the distribution of rDNA sites was investigated in representatives of 9 genera of Aurantioideae by FISH and CMA banding, aiming to understand the evolution of adjacent sites in the subfamily. A total of 57 rDNA sites were observed, 40 of them being adjacent to each other. All adjacent sites displayed the 45S rDNA array more terminally located. Assuming that the linked 5S-45S rDNA arrangement was the ancestral condition in Aurantioideae, the isolated rDNA sites observed in Clausena excavata,Bergera koenigii, and Fortunella obovata, as well as the complete linkage loss in Citrus maxima and C. medica indicates that unlinked sites arose independently several times in the evolution of the group. The linkage loss may be due to independent dispersion of one or both rDNA sequence families followed by deletion of the corresponding array in the adjacent site. The possible mechanisms behind these events and their occurrence in other groups are discussed.

  10. Analysis of Comparative Sequence and Genomic Data to Verify Phylogenetic Relationship and Explore a New Subfamily of Bacterial Lipases.

    Directory of Open Access Journals (Sweden)

    Malihe Masomian

    Full Text Available Thermostable and organic solvent-tolerant enzymes have significant potential in a wide range of synthetic reactions in industry due to their inherent stability at high temperatures and their ability to endure harsh organic solvents. In this study, a novel gene encoding a true lipase was isolated by construction of a genomic DNA library of thermophilic Aneurinibacillus thermoaerophilus strain HZ into Escherichia coli plasmid vector. Sequence analysis revealed that HZ lipase had 62% identity to putative lipase from Bacillus pseudomycoides. The closely characterized lipases to the HZ lipase gene are from thermostable Bacillus and Geobacillus lipases belonging to the subfamily I.5 with ≤ 57% identity. The amino acid sequence analysis of HZ lipase determined a conserved pentapeptide containing the active serine, GHSMG and a Ca(2+-binding motif, GCYGSD in the enzyme. Protein structure modeling showed that HZ lipase consisted of an α/β hydrolase fold and a lid domain. Protein sequence alignment, conserved regions analysis, clustal distance matrix and amino acid composition illustrated differences between HZ lipase and other thermostable lipases. Phylogenetic analysis revealed that this lipase represented a new subfamily of family I of bacterial true lipases, classified as family I.9. The HZ lipase was expressed under promoter Plac using IPTG and was characterized. The recombinant enzyme showed optimal activity at 65 °C and retained ≥ 97% activity after incubation at 50 °C for 1h. The HZ lipase was stable in various polar and non-polar organic solvents.

  11. Recognition of two major clades and early diverged groups within the subfamily Cyperoideae (Cyperaceae) including Korean sedges.

    Science.gov (United States)

    Jung, Jongduk; Choi, Hong-Keun

    2013-05-01

    We aim to present phylogenetic major groups within the subfamily Cyperoideae (Cyperaceae) on the basis of three molecular data sets; nuclear ribosomal internal transcribed spacer and 5.8S ribosomal RNA region, the ribulose-1, 5-bisphosphate carboxylase/oxygenase large subunit gene, and trnL intron and trnL-F intergenic spacer. Three molecular data and two combined data sets were used to obtain robust and detailed phylogenetic trees by using maximum parsimony and Bayesian inference, respectively. We analyzed 81 genera and 426 species of Cyperaceae, including Korean species. We suggest one early diverged group (EDGs), and two major clades (FAEC and SDC) within the subfamily Cyperoideae. And the clade EDGs comprises six tribes (Schoeneae, Bisboeckelereae, Sclerieae, Cryptangieae, Trilepideae, and Rhynchosporeae) at the basal nodes of Cyperoideae. The FAEC clade (posterior probability [PP]/bootstrap value [BS] = 1.00/85) comprises four tribes (Fuireneae, Abildgaardieae, Eleocharideae, Cypereae), and the SDC clade (PP/BS = 1.00/86) comprises three tribes (Scirpeae, Dulichieae, Cariceae). These three clades used for phylogenetic groups in our study will be useful for establishing the major lineage of the sedge family. The phylogeny of Korean sedges was also investigated within the whole phylogeny of Cyperaceae. The 20 genera of Korean sedges were placed in 10 tribes forming 14 clades.

  12. Resolution of phylogenetic relationships of the major subfamilies of the Delphacidae (Homoptera: Fulgoroidea) using the mitochondrial ribosomal DNA

    Institute of Scientific and Technical Information of China (English)

    EDDY DIJKSTRA; MICHEL A. SLOTMAN; RORY J. POST

    2006-01-01

    Delphacid relationships from the genus level to the subfamily have been completely resolved (among those taxa examined) using sequence data from the 3' end of the 12S gene. Monophyly of the non-asiracine subfamilies was strongly supported and the asiracine Ugyops was placed in the most basal position of the tree. Support levels for monophyly of the Delphacini increased after weighting transversions more heavily than transitions and after removing the cixiid outgroup from the dataset. Among the Delphacini,Conomelus and Megamelus were more closely related to each other than either was to Chloriona. These results are in agreement with the tree based on morphological characters. However, in contrast to morphological data our results strongly supported a sister group relationship between the Stenocraninae and the Kelisiinae. Although the 12S gene fragment gave some information about the species relationships within Chloriona, neither this fragment nor the 5' end of the 16S gene appear to be very useful for this level. Molecular evolutionary patterns provided evidence that there has been a shift in base composition from T to A during the early evolution of the non-Asiracinae. The non-Asiracinae also had comparatively fast substitution rates and these two observations are possibly correlated. In the 'modern' delphacid Chloriona, the AT content was comparatively low in regions free of constraints but this was not the case for 'non-modern' delphacids. The tRNA for valine has been translocated elsewhere, probably before the Delphacidae and Cixiidae diverged from each other.

  13. Testing the reliability of standard and complementary DNA barcodes for the monocot subfamily Alooideae from South Africa.

    Science.gov (United States)

    Daru, Barnabas H; van der Bank, Michelle; Bello, Abubakar; Yessoufou, Kowiyou

    2016-11-23

    Although a standard DNA barcode has been identified for plants, it does not always provide species-level specimen identifications for investigating important ecological questions. In this study, we assessed the species-level discriminatory power of standard (rbcLa + matK) and complementary barcodes (ITS1 and trnH-psbA) within the subfamily Alooideae (Asphodelaceae), a large and recent plant radiation, whose species are important in horticulture yet are threatened. Alooideae has its centre of endemism in southern Africa, with some outlier species occurring elsewhere in Africa and Madagascar. We sampled 360 specimens representing 235 species within all 11 genera of the subfamily. With three distance-based methods, all markers performed poorly for our combined data set, with the highest proportion of correct species-level specimen identifications (30%) found for ITS1. However, when performance was assessed across genera, the discriminatory power varied from 0% for all single markers and combinations in Gasteria to 63% in Haworthiopsis, again for ITS1, suggesting that DNA barcoding success may be related to the evolutionary history of the lineage considered. Although ITS1 could be a good barcode for Haworthiopsis, the generally poor performance of all markers suggests that Alooideae remains a challenge. As species boundaries within Alooideae remain controversial, we call for continued search for suitable markers or the use of genomics approaches to further explore species discrimination in the group.

  14. Relationships among the cyclostome braconid (Hymenoptera: Braconidae) subfamilies inferred from a mitochondrial tRNA gene rearrangement.

    Science.gov (United States)

    Dowton, M

    1999-03-01

    The arrangement of mitochondrial tRNA genes for lysine (K) and aspartate (D) from the junction of the cytochrome oxidase II and ATPase 8 genes was determined in a range of hymenopteran taxa. This indicated that the ancestral arrangement for the order is 'KD', as found in the Diptera (represented by Drosophila and Anopheles) and basal Orthoptera. Most Hymenoptera that evolved after the appearance of parasitism also have the 'KD' arrangement, including noncyclostome braconids. However, most cyclostome braconids have either a 'DK' or a 'DHK' arrangement (where 'H' refers to the tRNA gene for Histidine). In both cases, the aspartate tRNA gene is encoded on the mitochondrial N-strand, rather than the J-strand as is usually the case. This rearrangement identified a monophyletic group not previously recognized, consisting of Rogadinae + Braconinae + Gnamptodontinae + Histeromerinae + Rhyssalinae + Betylobraconinae + Opiinae + Alysiinae. Only one cyclostome subfamily (Doryctinae) retained the 'KD' arrangement, suggesting this to be the most basal of the cyclostome subfamilies, consistent with ectoparasitism being plesiomorphic for the cyclostomes. However, the Aphidiinae also retained the 'KD' arrangement, leaving unresolved the issue of whether they should be included within the cyclostomes.

  15. Strategies of karyotype differentiation in Elateridae (Coleoptera, Polyphaga).

    Science.gov (United States)

    Schneider, Marielle Cristina; Rosa, Simone Policena; Almeida, Mara Cristina; Costa, Cleide; Cella, Doralice Maria

    2007-01-01

    The chromosome study of five species of the family Elateridae, belonging to the subfamilies Agrypninae and Elaterinae, and the analysis of the cytogenetic data previously recorded for this family permitted the establishment of the main strategies of karyotypic differentiation that has occurred in the elaterids. In Agrypninae, the three species studied (Conoderus fuscofasciatus, Conoderus rufidens, and Conoderus sp.) showed the male karyotype 2n=16+X0. This karyotypic uniformity detected in these Conoderus species has also been shared with other species of the same genus, differing considerably from chromosomal heterogeneity verified in the subfamily Agrypninae. The use of the C-banding technique in C. fuscofasciatus and Conoderus sp. revealed constitutive heterochromatin in the pericentromeric region of the majority of the chromosomes. In C. fuscofasciatus, additional constitutive heterochromatin were also observed in the long arm terminal region of almost all chromosomes. Among the representatives of Elaterinae, the karyotype 2n=18+Xy(p) of Pomachilius sp.2 was similar to that verified in the majority of the Coleoptera species, contrasting with the chromosomal formula 2n=18+X0 detected in Cardiorhinus rufilateris, which is most common in the species of Elaterinae. In the majority of the elaterids, the chromosomal differentiation has frequently been driven by reduction of the diploid number; but, among the four cytogenetically examined subfamilies, there are some differences in relation to the trends of karyotypic evolution.

  16. Autoinhibitory Interdomain Interactions and Subfamily-specific Extensions Redefine the Catalytic Core of the Human DEAD-box Protein DDX3.

    Science.gov (United States)

    Floor, Stephen N; Condon, Kendall J; Sharma, Deepak; Jankowsky, Eckhard; Doudna, Jennifer A

    2016-01-29

    DEAD-box proteins utilize ATP to bind and remodel RNA and RNA-protein complexes. All DEAD-box proteins share a conserved core that consists of two RecA-like domains. The core is flanked by subfamily-specific extensions of idiosyncratic function. The Ded1/DDX3 subfamily of DEAD-box proteins is of particular interest as members function during protein translation, are essential for viability, and are frequently altered in human malignancies. Here, we define the function of the subfamily-specific extensions of the human DEAD-box protein DDX3. We describe the crystal structure of the subfamily-specific core of wild-type DDX3 at 2.2 Å resolution, alone and in the presence of AMP or nonhydrolyzable ATP. These structures illustrate a unique interdomain interaction between the two ATPase domains in which the C-terminal domain clashes with the RNA-binding surface. Destabilizing this interaction accelerates RNA duplex unwinding, suggesting that it is present in solution and inhibitory for catalysis. We use this core fragment of DDX3 to test the function of two recurrent medulloblastoma variants of DDX3 and find that both inactivate the protein in vitro and in vivo. Taken together, these results redefine the structural and functional core of the DDX3 subfamily of DEAD-box proteins.

  17. HCV Proteins and Immunoglobulin Variable Gene (IgV Subfamilies in HCV-Induced Type II Mixed Cryoglobulinemia: A Concurrent Pathogenetic Role

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    Giuseppe Sautto

    2012-01-01

    Full Text Available The association between hepatitis C virus (HCV infection and type II mixed cryoglobulinemia (MCII is well established, but the role played by distinct HCV proteins and by specific components of the anti-HCV humoral immune response remains to be clearly defined. It is widely accepted that HCV drives the expansion of few B-cell clones expressing a restricted pool of selected immunoglobulin variable (IgV gene subfamilies frequently endowed with rheumatoid factor (RF activity. Moreover, the same IgV subfamilies are frequently observed in HCV-transformed malignant B-cell clones occasionally complicating MCII. In this paper, we analyze both the humoral and viral counterparts at the basis of cryoglobulins production in HCV-induced MCII, with particular attention reserved to the single IgV subfamilies most frequently involved.

  18. NR-2L: a two-level predictor for identifying nuclear receptor subfamilies based on sequence-derived features.

    Directory of Open Access Journals (Sweden)

    Pu Wang

    Full Text Available Nuclear receptors (NRs are one of the most abundant classes of transcriptional regulators in animals. They regulate diverse functions, such as homeostasis, reproduction, development and metabolism. Therefore, NRs are a very important target for drug development. Nuclear receptors form a superfamily of phylogenetically related proteins and have been subdivided into different subfamilies due to their domain diversity. In this study, a two-level predictor, called NR-2L, was developed that can be used to identify a query protein as a nuclear receptor or not based on its sequence information alone; if it is, the prediction will be automatically continued to further identify it among the following seven subfamilies: (1 thyroid hormone like (NR1, (2 HNF4-like (NR2, (3 estrogen like, (4 nerve growth factor IB-like (NR4, (5 fushi tarazu-F1 like (NR5, (6 germ cell nuclear factor like (NR6, and (7 knirps like (NR0. The identification was made by the Fuzzy K nearest neighbor (FK-NN classifier based on the pseudo amino acid composition formed by incorporating various physicochemical and statistical features derived from the protein sequences, such as amino acid composition, dipeptide composition, complexity factor, and low-frequency Fourier spectrum components. As a demonstration, it was shown through some benchmark datasets derived from the NucleaRDB and UniProt with low redundancy that the overall success rates achieved by the jackknife test were about 93% and 89% in the first and second level, respectively. The high success rates indicate that the novel two-level predictor can be a useful vehicle for identifying NRs and their subfamilies. As a user-friendly web server, NR-2L is freely accessible at either http://icpr.jci.edu.cn/bioinfo/NR2L or http://www.jci-bioinfo.cn/NR2L. Each job submitted to NR-2L can contain up to 500 query protein sequences and be finished in less than 2 minutes. The less the number of query proteins is, the shorter the time will

  19. NR-2L: a two-level predictor for identifying nuclear receptor subfamilies based on sequence-derived features.

    Science.gov (United States)

    Wang, Pu; Xiao, Xuan; Chou, Kuo-Chen

    2011-01-01

    Nuclear receptors (NRs) are one of the most abundant classes of transcriptional regulators in animals. They regulate diverse functions, such as homeostasis, reproduction, development and metabolism. Therefore, NRs are a very important target for drug development. Nuclear receptors form a superfamily of phylogenetically related proteins and have been subdivided into different subfamilies due to their domain diversity. In this study, a two-level predictor, called NR-2L, was developed that can be used to identify a query protein as a nuclear receptor or not based on its sequence information alone; if it is, the prediction will be automatically continued to further identify it among the following seven subfamilies: (1) thyroid hormone like (NR1), (2) HNF4-like (NR2), (3) estrogen like, (4) nerve growth factor IB-like (NR4), (5) fushi tarazu-F1 like (NR5), (6) germ cell nuclear factor like (NR6), and (7) knirps like (NR0). The identification was made by the Fuzzy K nearest neighbor (FK-NN) classifier based on the pseudo amino acid composition formed by incorporating various physicochemical and statistical features derived from the protein sequences, such as amino acid composition, dipeptide composition, complexity factor, and low-frequency Fourier spectrum components. As a demonstration, it was shown through some benchmark datasets derived from the NucleaRDB and UniProt with low redundancy that the overall success rates achieved by the jackknife test were about 93% and 89% in the first and second level, respectively. The high success rates indicate that the novel two-level predictor can be a useful vehicle for identifying NRs and their subfamilies. As a user-friendly web server, NR-2L is freely accessible at either http://icpr.jci.edu.cn/bioinfo/NR2L or http://www.jci-bioinfo.cn/NR2L. Each job submitted to NR-2L can contain up to 500 query protein sequences and be finished in less than 2 minutes. The less the number of query proteins is, the shorter the time will

  20. Biogeography of the leafhopper subfamily Stegelytrinae (Hemiptera: Cicadellidae), based on a cluster analysis of geographical distribution in areas of endemism combined with phylogeny of the subfamily%世界秀头叶蝉亚科生物地理学

    Institute of Scientific and Technical Information of China (English)

    魏琮; 程若琳; 张雅林

    2012-01-01

    Biogeography of the leafhopper subfamily Stegelytrinae Baker is studied based on an analysis of geographical distribution of this subfamily worldwide using a cluster analysis of the zoological distribution of areas of endemism as well as the phylogeny of representatives of this subfamily.Results show that the Stegelytrinae mainly occur in the Oriental Region and in the Mediterranean area of the Palaearctic Region,and this extends to the east side of both Wallace's and Weber's lines.Eleven areas of endemism of this subfamily are recognized.The proportions of endemic taxa in different areas of endemism are generally very high in comparison with other leafhopper groups,but distinct differences could be found among the different areas of endemism of Stegelytrinae.This subfamily is most intensively diversified in the Indochina Peninsula (INCN).This is the stegelytrine distribution center,having the highest biodiversity at both generic and species levels.The dendrogram of endemic areas of Stegelytrinae constructed using cluster analysis of the zoological distribution of Stegelytrinae at generic level shows the endemic areas of Stegelytrinae can be divided into 4 large groups.Relationships among different endemic areas of Stegelytrinae correspond largely to the geologic history of related areas,which indicates that the evolution and vicariance of this subfamily have been closely related to the history of continental drift and climate changes.It is deduced that the presumed monophyletic Stegelytrinae originated in the Oriental Region after North America had separated from Eurasia; this is the case in the monophyletic genera group which is supported by the lateral frontal sutures extending dorsally well beyond the corresponding ocellus.In addition,two expanding traces of the Stegelytrinae are presumed,which remain plausible explanations for the dispersal of Stegelytrinae:(1) New Guinea (and probably (+ Australia)) -Kalimantan-Sumatra-Malay Peninsula-Indochina Peninsula

  1. The Subfamily-Specific Interaction between Kv2.1 and Kv6.4 Subunits Is Determined by Interactions between the N- and C-termini

    OpenAIRE

    Elke Bocksteins; Evy Mayeur; Abbi Van Tilborg; Glenn Regnier; Jean-Pierre Timmermans; Snyders, Dirk J

    2014-01-01

    The "silent" voltage-gated potassium (KvS) channel subunit Kv6.4 does not form electrically functional homotetramers at the plasma membrane but assembles with Kv2.1 subunits, generating functional Kv2.1/Kv6.4 heterotetramers. The N-terminal T1 domain determines the subfamily-specific assembly of Kv1-4 subunits by preventing interactions between subunits that belong to different subfamilies. For Kv6.4, yeast-two-hybrid experiments showed an interaction of the Kv6.4 N-terminus with the Kv2.1 N-...

  2. Recent advances regarding the role of ABC subfamily C member 10 (ABCC10) in the efflux of antitumor drugs

    Institute of Scientific and Technical Information of China (English)

    Rishil J. Kathawala; Yi-Jun Wang; Charles R. Ashby Jr; Zhe-Sheng Chen

    2014-01-01

    ABCC10, also known as multidrug-resistant protein 7 (MRP7), is the tenth member of the C subfamily of the ATP-binding cassette (ABC) superfamily. ABCC10 mediates multidrug resistance (MDR) in cancer cells by preventing the intracellular accumulation of certain antitumor drugs. The ABCC10 transporter is a 171-kDa protein that is localized on the basolateral cell membrane. ABCC10 is a broad-specificity transporter of xenobiotics, including antitumor drugs, such as taxanes, epothilone B, vinca alkaloids, and cytarabine, as wel as modulators of the estrogen pathway, such as tamoxifen. In recent years, ABCC10 inhibitors, including cepharanthine, lapatinib, erlotinib, nilotinib, imatinib, sildenafil, and vardenafil, have been reported to overcome ABCC10-mediated MDR. This review discusses some recent and clinically relevant aspects of the ABCC10 drug efflux transporter from the perspective of current chemotherapy, particularly its inhibition by tyrosine kinase inhibitors and phosphodiesterase type 5 inhibitors.

  3. TCR gene segments from at least one third of V alpha subfamilies rearrange at the delta locus.

    Science.gov (United States)

    Genevée, C; Chung, V; Diu, A; Hercend, T; Triebel, F

    1994-02-01

    Using PCR and an experimentally validated V alpha subfamily-specific oligonucleotide panel (V alpha 1-w29), we have investigated whether the TCR delta chain may increase its combinatorial diversity by using V genes considered as alpha chain-specific. We show that at least 10 distinct human V alpha segments rearrange at the J delta locus, leading to scrambling of the two V gene repertoires. Fifty-five per cent of the V alpha/J delta transcripts characterized here were in frame. The 17 V alpha/C delta chains analysed included an extended CDR3 region with up to 18 aa encoded by the junctional region. In addition, a new J delta segment (J delta 4) has been characterized. Together, these findings demonstrate that combinatorial diversity in the human delta locus is larger than previously thought.

  4. The structure of SAV1646 from Staphylococcus aureus belonging to a new `ribosome-associated' subfamily of bacterial proteins.

    Science.gov (United States)

    Chirgadze, Yuri N; Clarke, Teresa E; Romanov, Vladimir; Kisselman, Gera; Wu-Brown, Jean; Soloveychik, Maria; Chan, Tiffany S Y; Gordon, Roni D; Battaile, Kevin P; Pai, Emil F; Chirgadze, Nickolay Y

    2015-02-01

    The crystal structure of the SAV1646 protein from the pathogenic microorganism Staphylococcus aureus has been determined at 1.7 Å resolution. The 106-amino-acid protein forms a two-layer sandwich with α/β topology. The protein molecules associate as dimers in the crystal and in solution, with the monomers related by a pseudo-twofold rotation axis. A sequence-homology search identified the protein as a member of a new subfamily of yet uncharacterized bacterial `ribosome-associated' proteins with at least 13 members to date. A detailed analysis of the crystal protein structure along with the genomic structure of the operon containing the sav1646 gene allowed a tentative functional model of this protein to be proposed. The SAV1646 dimer is assumed to form a complex with ribosomal proteins L21 and L27 which could help to complete the assembly of the large subunit of the ribosome.

  5. Phylogeny and evolution of the auks (subfamily Alcinae) based on mitochondrial DNA sequences

    Science.gov (United States)

    Moum, Truls; Johansen, Steinar; Erikstad, Kjell Einar; Piatt, John F.

    1994-01-01

    The genetic divergence and phylogeny of the auks was assessed by mitochondrial DNA sequence comparisons in a study using 19 of the 22 auk species and two outgroup representatives. We compared more than 500 nucleotides from each of two mitochondrial genes encoding 12S rRNA and the NADH dehydrogenase subunit 6. Divergence times were estimated from transversional substitutions. The dovekie (Alle alle) is related to the razorbill (Alca torda) and the murres (Uria spp). Furthermore, the Xantus's murrelet (Synthliboramphus hypoleucus) and the ancient (Synthliboramphus antiquus) and Japanese murrelets (Synthliboramphus wumizusume) are genetically distinct members of the same main lineage, whereas brachyramphine and synthliboramphine murrelets are not closely related. An early adaptive radiation of six main species groups of auks seems to trace back to Middle Miocene. Later speciation probably involved ecological differentiations and geographical isolations.

  6. Structural and Functional Analysis of a New Subfamily of Glycosyltransferases Required for Glycosylation of Serine-rich Streptococcal Adhesins

    Energy Technology Data Exchange (ETDEWEB)

    Zhu, Fan; Erlandsen, Heidi; Ding, Lei; Li, Jingzhi; Huang, Ying; Zhou, Meixian; Liang, Xiaobo; Ma, Jinbiao; Wu, Hui (UAB)

    2011-09-16

    Serine-rich repeat glycoproteins (SRRPs) are a growing family of bacterial adhesins found in many streptococci and staphylococci; they play important roles in bacterial biofilm formation and pathogenesis. Glycosylation of this family of adhesins is essential for their biogenesis. A glucosyltransferase (Gtf3) catalyzes the second step of glycosylation of a SRRP (Fap1) from an oral streptococcus, Streptococcus parasanguinis. Although Gtf3 homologs are highly conserved in SRRP-containing streptococci, they share minimal homology with functionally known glycosyltransferases. We report here the 2.3 {angstrom} crystal structure of Gtf3. The structural analysis indicates that Gtf3 forms a tetramer and shares significant structural homology with glycosyltransferases from GT4, GT5, and GT20 subfamilies. Combining crystal structural analysis with site-directed mutagenesis and in vitro glycosyltransferase assays, we identified residues that are required for UDP- or UDP-glucose binding and for oligomerization of Gtf3 and determined their contribution to the enzymatic activity of Gtf3. Further in vivo studies revealed that the critical amino acid residues identified by the structural analysis are crucial for Fap1 glycosylation in S. parasanguinis in vivo. Moreover, Gtf3 homologs from other streptococci were able to rescue the gtf3 knock-out mutant of S. parasanguinis in vivo and catalyze the sugar transfer to the modified SRRP substrate in vitro, demonstrating the importance and conservation of the Gtf3 homologs in glycosylation of SRRPs. As the Gtf3 homologs only exist in SRRP-containing streptococci, we conclude that the Gtf3 homologs represent a unique subfamily of glycosyltransferases.

  7. A Species-Level Phylogeny of Extant Snakes with Description of a New Colubrid Subfamily and Genus

    Science.gov (United States)

    McKelvy, Alexander D.; Grismer, L. Lee; Bell, Charles D.; Lailvaux, Simon P.

    2016-01-01

    Background With over 3,500 species encompassing a diverse range of morphologies and ecologies, snakes make up 36% of squamate diversity. Despite several attempts at estimating higher-level snake relationships and numerous assessments of generic- or species-level phylogenies, a large-scale species-level phylogeny solely focusing on snakes has not been completed. Here, we provide the largest-yet estimate of the snake tree of life using maximum likelihood on a supermatrix of 1745 taxa (1652 snake species + 7 outgroup taxa) and 9,523 base pairs from 10 loci (5 nuclear, 5 mitochondrial), including previously unsequenced genera (2) and species (61). Results Increased taxon sampling resulted in a phylogeny with a new higher-level topology and corroborate many lower-level relationships, strengthened by high nodal support values (> 85%) down to the species level (73.69% of nodes). Although the majority of families and subfamilies were strongly supported as monophyletic with > 88% support values, some families and numerous genera were paraphyletic, primarily due to limited taxon and loci sampling leading to a sparse supermatrix and minimal sequence overlap between some closely-related taxa. With all rogue taxa and incertae sedis species eliminated, higher-level relationships and support values remained relatively unchanged, except in five problematic clades. Conclusion Our analyses resulted in new topologies at higher- and lower-levels; resolved several previous topological issues; established novel paraphyletic affiliations; designated a new subfamily, Ahaetuliinae, for the genera Ahaetulla, Chrysopelea, Dendrelaphis, and Dryophiops; and appointed Hemerophis (Coluber) zebrinus to a new genus, Mopanveldophis. Although we provide insight into some distinguished problematic nodes, at the deeper phylogenetic scale, resolution of these nodes may require sampling of more slowly-evolving nuclear genes. PMID:27603205

  8. The search for therapeutic bacteriophages uncovers one new subfamily and two new genera of Pseudomonas-infecting Myoviridae.

    Directory of Open Access Journals (Sweden)

    Marine Henry

    Full Text Available In a previous study, six virulent bacteriophages PAK_P1, PAK_P2, PAK_P3, PAK_P4, PAK_P5 and CHA_P1 were evaluated for their in vivo efficacy in treating Pseudomonas aeruginosa infections using a mouse model of lung infection. Here, we show that their genomes are closely related to five other Pseudomonas phages and allow a subdivision into two clades, PAK_P1-like and KPP10-like viruses, based on differences in genome size, %GC and genomic contents, as well as number of tRNAs. These two clades are well delineated, with a mean of 86% and 92% of proteins considered homologous within individual clades, and 25% proteins considered homologous between the two clades. By ESI-MS/MS analysis we determined that their virions are composed of at least 25 different proteins and electron microscopy revealed a morphology identical to the hallmark Salmonella phage Felix O1. A search for additional bacteriophage homologs, using profiles of protein families defined from the analysis of the 11 genomes, identified 10 additional candidates infecting hosts from different species. By carrying out a phylogenetic analysis using these 21 genomes we were able to define a new subfamily of viruses, the Felixounavirinae within the Myoviridae family. The new Felixounavirinae subfamily includes three genera: Felixounalikevirus, PAK_P1likevirus and KPP10likevirus. Sequencing genomes of bacteriophages with therapeutic potential increases the quantity of genomic data on closely related bacteriophages, leading to establishment of new taxonomic clades and the development of strategies for analyzing viral genomes as presented in this article.

  9. Phylogenetic analysis and expression patterns of Pax genes in the onychophoran Euperipatoides rowelli reveal a novel bilaterian Pax subfamily.

    Science.gov (United States)

    Franke, Franziska Anni; Schumann, Isabell; Hering, Lars; Mayer, Georg

    2015-01-01

    Pax family genes encode a class of transcription factors that regulate various developmental processes. To shed light on the evolutionary history of these genes in Panarthropoda (Onychophora + Tardigrada + Arthropoda), we analyzed the Pax repertoire in the embryonic and adult transcriptomes of the onychophoran Euperipatoides rowelli. Our data revealed homologs of all five major bilaterian Pax subfamilies in this species, including Pax2/5/8, Pax4/6, Pox-neuro, Pax1/9/Pox-meso, and Pax3/7. In addition, we identified a new Pax member, pax-α, which does not fall into any other known Pax subfamily but instead clusters in the heterogenic Pax-α/β clade containing deuterostome, ecdysozoan, and lophotrochozoan gene sequences. These findings suggest that the last common bilaterian ancestor possessed six rather than five Pax genes, which have been retained in the panarthropod lineage. The expression data of Pax orthologs in the onychophoran embryo revealed distinctive patterns, some of which might be related to their ancestral roles in the last common panarthropod ancestor, whereas others might be specific to the onychophoran lineage. The derived roles include, for example, an involvement of pax2/5/8, pox-neuro, and pax3/7 in onychophoran nephridiogenesis, and an additional function of pax2/5/8 in the formation of the ventral and preventral organs. Furthermore, our transcriptomic analyses suggest that at least some Pax genes, including pax6 and pax-α, are expressed in the adult onychophoran head, although the corresponding functions remain to be clarified. The remarkable diversity of the Pax expression patterns highlights the functional and evolutionary plasticity of these genes in panarthropods.

  10. In silico cloning and characterization of the TGA (TGACG MOTIF-BINDING FACTOR) transcription factors subfamily in Carica papaya.

    Science.gov (United States)

    Idrovo Espín, Fabio Marcelo; Peraza-Echeverria, Santy; Fuentes, Gabriela; Santamaría, Jorge M

    2012-05-01

    The TGA transcription factors belong to the subfamily of bZIP group D that play a major role in disease resistance and development. Most of the TGA identified in Arabidopsis interact with the master regulator of SAR, NPR1 that controls the expression of PR genes. As a first approach to determine the possible involvement of these transcription factors in papaya defense, we characterized Arabidopsis TGA orthologs from the genome of Carica papaya cv. SunUp. Six orthologs CpTGA1 to CpTGA6, were identified. The predicted CpTGA proteins were highly similar to AtTGA sequences and probably share the same DNA binding properties and transcriptional regulation features. The protein sequences alignment evidenced the presence of conserved domains, characteristic of this group of transcription factors. The phylogeny showed that CpTGA evolved into three different subclades associated with defense and floral development. This is the first report of basal expression patterns assessed by RT-PCR, from the whole subfamily of CpTGA members in different tissues from papaya cv. Maradol mature plants. Overall, CpTGA1, CpTGA3 CpTGA6 and CpTGA4 showed a basal expression in all tissues tested; CpTGA2 expressed strongly in all tissues except in petioles while CpTGA5 expressed only in petals and to a lower extent in petioles. Although more detailed studies in anthers and other floral structures are required, we suggest that CpTGA5 might be tissue-specific, and it might be involved in papaya floral development. On the other hand, we report here for the first time, the expression of the whole family of CpTGA in response to salicylic acid (SA). The expression of CpTGA3, CpTGA4 and CpTGA6 increased in response to SA, what would suggest its involvement in the SAR response in papaya.

  11. Sonorensin: an antimicrobial peptide, belonging to the heterocycloanthracin subfamily of bacteriocins, from a new marine isolate, Bacillus sonorensis MT93.

    Science.gov (United States)

    Chopra, Lipsy; Singh, Gurdeep; Choudhary, Vikas; Sahoo, Debendra K

    2014-05-01

    Marine environments are the greatest fronts of biodiversity, representing a resource of unexploited or unknown microorganisms and new substances having potential applications. Among microbial products, antimicrobial peptides (AMPs) have received great attention recently due to their applications as food preservatives and therapeutic agents. A new marine soil isolate producing an AMP was identified as Bacillus sonorensis based on 16S rRNA gene sequence analysis. It produced an AMP that showed a broad spectrum of activity against both Gram-positive and Gram-negative bacteria. The peptide, named sonorensin, was purified to homogeneity using a combination of chromatographic techniques. The intact molecular mass of the purified peptide, 6,274 Da, as revealed by matrix-assisted laser desorption ionization-time of flight (MALDI-TOF), was in agreement with Tricine-SDS-PAGE analysis. A PCR array of primers was used to identify AMP structural genes, which allowed the successful amplification of the related genes from strain MT93. The putative open reading frame of sonorensin was amplified, cloned into the pET-32a(+) vector, expressed as a thioredoxin (Trx) fusion protein in Escherichia coli, and then purified. Sequence alignment analysis revealed that the bacteriocin being reported could belong to new subfamily of bacteriocins, heterocycloanthracin. The peptide indicated its potential as a biocontrol agent or food antimicrobial agent, due to its antimicrobial activity against bacteria such as Listeria monocytogenes and Staphylococcus aureus. This is the first report of the production, purification, and characterization of wild-type and recombinant bacteriocin by B. sonorensis and the first bacteriocin of the heterocycloanthracin subfamily to be characterized.

  12. Prevalent Exon-Intron Structural Changes in the APETALA1/FRUITFULL, SEPALLATA, AGAMOUS-LIKE6, and FLOWERING LOCUS C MADS-Box Gene Subfamilies Provide New Insights into Their Evolution.

    Science.gov (United States)

    Yu, Xianxian; Duan, Xiaoshan; Zhang, Rui; Fu, Xuehao; Ye, Lingling; Kong, Hongzhi; Xu, Guixia; Shan, Hongyan

    2016-01-01

    AP1/FUL, SEP, AGL6, and FLC subfamily genes play important roles in flower development. The phylogenetic relationships among them, however, have been controversial, which impedes our understanding of the origin and functional divergence of these genes. One possible reason for the controversy may be the problems caused by changes in the exon-intron structure of genes, which, according to recent studies, may generate non-homologous sites and hamper the homology-based sequence alignment. In this study, we first performed exon-by-exon alignments of these and three outgroup subfamilies (SOC1, AG, and STK). Phylogenetic trees reconstructed based on these matrices show improved resolution and better congruence with species phylogeny. In the context of these phylogenies, we traced evolutionary changes of exon-intron structures in each subfamily. We found that structural changes have occurred frequently following gene duplication and speciation events. Notably, exons 7 and 8 (if present) suffered more structural changes than others. With the knowledge of exon-intron structural changes, we generated more reasonable alignments containing all the focal subfamilies. The resulting trees showed that the SEP subfamily is sister to the monophyletic group formed by AP1/FUL and FLC subfamily genes and that the AGL6 subfamily forms a sister group to the three abovementioned subfamilies. Based on this topology, we inferred the evolutionary history of exon-intron structural changes among different subfamilies. Particularly, we found that the eighth exon originated before the divergence of AP1/FUL, FLC, SEP, and AGL6 subfamilies and degenerated in the ancestral FLC-like gene. These results provide new insights into the origin and evolution of the AP1/FUL, FLC, SEP, and AGL6 subfamilies.

  13. Enzymes of the AKR1B and AKR1C subfamilies and uterine diseases

    Directory of Open Access Journals (Sweden)

    Tea eLanisnik Rizner

    2012-03-01

    Full Text Available Endometrial and cervical cancers, uterine myoma, and endometriosis are very common uterine diseases. Worldwide, more than 800,000 women are affected annually by gynecological cancers, as a result of which, more than 360,000 die. During their reproductive age, about 70% of women develop uterine myomas, 10% to 15% suffer from endometriosis, and 35% to 50% from infertility associated with endometriosis. Uterine diseases are associated with aberrant inflammatory responses and concomitant increased production of prostaglandins (PG. They are also related to decreased differentiation, due to low levels of protective progesterone and retinoic acid, and to enhanced proliferation, due to high local concentrations of estrogens. The pathogenesis of these diseases can thus be attributed to disturbed PG, estrogen and retinoid metabolism and actions. Five human members of the aldo-keto reductase 1B (AKR1B and 1C (AKR1C superfamilies, i.e., AKR1B1, AKR1B10, AKR1C1, AKR1C2 and AKR1C3, have roles in these processes and can thus be implicated in uterine diseases. AKR1B1 and AKR1C3 catalyze the formation of PGF2alpha which stimulates cell proliferation. AKR1C3 converts PGD2 to 9alpha,11beta-PGF2, and thus counteracts the formation of 15deoxy-PGJ2, which can activate pro-apoptotic peroxisome-proliferator-activated receptor beta. AKR1B10 catalyzes the reduction of retinal to retinol, and in thus lessens the formation of retinoic acid, with potential pro-differentiating actions. The AKR1C1-AKR1C3 enzymes also act as 17-keto- and 20-ketosteroid reductases to varying extents, and are implicated in increased estradiol and decreased progesterone levels. This review comprises a short introduction to uterine diseases, followed by an overview of the current literature on the AKR1B and AKR1C expression in the uterus and in uterine diseases. The potential implications of the AKR1B and AKR1C enzymes and their pathophysiologies are then discussed, followed by conclusions and

  14. Design factors that influence the performance of flight intercept traps for the capture of longhorned beetles (Coleoptera: Cerambycidae) from the subfamilies Lamiinae and Cerambycinae.

    Science.gov (United States)

    Allison, Jeremy D; Bhandari, Basu D; McKenney, Jessica L; Millar, Jocelyn G

    2014-01-01

    In North America, cerambycid beetles can have significant ecological and economic effects on forest ecosystems, and the rate of introduction and/or detection of exotic species is increasing. Detection and survey programs rely on semiochemical-baited intercept traps which are often ineffective for large woodborers like cerambycid beetles. This study examined the effects of flight intercept trap design on the capture of cerambycid beetles in the subfamilies Lamiinae and Cerambycinae. These subfamilies are the two largest in the Cerambycidae and they include many of the most damaging cerambycid pests and species on regulatory watch lists in North America. This study demonstrates that intercept trap design, treatment of trap surfaces with a lubricant, and the type of collection cup all influence the capture of beetles from the subfamilies Lamiinae and Cerambycinae. It also demonstrates that the addition of a large lubricant-treated collar to the bottom funnel of a multiple-funnel trap significantly increases the capture of some Lamiinae. The best trap design for both subfamilies was a lubricant treated multiple-funnel [MF] trap equipped with a wet cup and lubricant treated large collar on the bottom funnel. This design captured between 4 and 14 times more Lamiinae and Cerambycinae than commercially-available MF and panel traps.

  15. New case of lateral asymmetry in fishes: A new subfamily, genus and species of deep water clingfishes from Papua New Guinea, western Pacific Ocean.

    Science.gov (United States)

    Fricke, Ronald; Chen, Jhen-Nien; Chen, Wei-Jen

    2017-01-01

    The unusual clingfish Protogobiesox asymmetricus n. gen, n. sp. is described on the basis of four specimens collected in deep water off the north coast of Papua New Guinea in 2012. The species is characterized by its 9-10 dorsal rays, 8 anal rays, 17-24 pectoral-fin rays, 15 principal caudal-fin rays, 3 gills, third arch with 3 gill rakers, 34-35 total vertebrae, with asymmetrical lateral bending starting behind the skull, bent at an angle of 85°-92°; skull asymmetrical in frontal view; skin naked, surface of head and body without striae; disc without adhesive papillae. A new subfamily Protogobiesocinae is described for this species and Lepadicyathus mendeleevi Prokofiev, 2005, which is redescribed. The new subfamily is compared within the family; keys to the subfamilies of Gobiesocidae and the species within the new subfamily are presented; its phylogenetic relationship to other gobiesocids is inferred based on a multi-locus DNA dataset.

  16. Discovery of a living fossil: a new xylastodorine species from New Caledonia (Heteroptera: Thaumastocoridae) and first record of the subfamily from the eastern Hemisphere

    NARCIS (Netherlands)

    Doesburg, van P.H.; Cassis, G.; Monteith, G.B.

    2010-01-01

    A new species belonging to the genus Proxylastodoris Heiss & Popov, 2002, P. kuscheli spec. nov., of the subfamily Xylastodorinae Barber, 1920 (Heteroptera: Thaumastocoridae) is described from New Caledonia. It is the first recent record outside the western Hemisphere of the Xyalstodorinae and is th

  17. Phylogeny of Bromelioideae (Bromeliaceae) inferred from nuclear and plastid DNA loci reveals the evolution of the tank habit within the subfamily.

    Science.gov (United States)

    Schulte, Katharina; Barfuss, Michael H J; Zizka, Georg

    2009-05-01

    Phylogenetic relationships within subfamily Bromelioideae (Bromeliaceae, Poales) were inferred using DNA sequence data from the low-copy nuclear gene phosphoribulokinase (PRK) and five plastid loci (matK gene, 3'trnK intron, trnL intron, trnL-trnF spacer, atpB-rbcL spacer). The PRK dataset exhibited a considerably higher proportion of potentially informative characters than the plastid dataset (16.9% vs. 3.1%), leading to a higher resolution and improved nodal support of the resulting phylogenies. Bromelia is resolved as sister to the remainder of the subfamily, albeit this relationship receives only weak nodal support. The basal position of Bromelia, as well as Deinacanthon, Greigia, Ochagavia, Fascicularia and Fernseea within the subfamily is corroborated and the remainder of the subfamily forms a highly supported clade (the eu-bromelioids). By the inclusion of nuclear data the sister group position of Fernseea to the eu-bromelioids is now highly supported. Within the eu-bromelioids the resolution of the clade representing the more advanced core bromelioids has increased and further demonstrates the highly problematic generic concept of Aechmea as well as Quesnelia. Moreover, the data were used to examine the evolution of sepal symmetry and the tank habit. Tracing of character transitions onto the molecular phylogeny implies that both characters have undergone only few transitions within the subfamily and thus are not as homoplasious as previously assumed. The character state reconstruction reveals the great importance of the evolution of the tank habit for the diversification of the core bromelioids.

  18. Differential characters

    CERN Document Server

    Bär, Christian

    2014-01-01

    Providing a systematic introduction to differential characters as introduced by Cheeger and Simons, this text describes important concepts such as fiber integration, higher dimensional holonomy, transgression, and the product structure in a geometric manner. Differential characters form a model of what is nowadays called differential cohomology, which is the mathematical structure behind the higher gauge theories in physics.  

  19. Insect Resistance to Bacillus thuringiensis Toxin Cry2Ab Is Conferred by Mutations in an ABC Transporter Subfamily A Protein.

    Directory of Open Access Journals (Sweden)

    Wee Tek Tay

    2015-11-01

    Full Text Available The use of conventional chemical insecticides and bacterial toxins to control lepidopteran pests of global agriculture has imposed significant selection pressure leading to the rapid evolution of insecticide resistance. Transgenic crops (e.g., cotton expressing the Bt Cry toxins are now used world wide to control these pests, including the highly polyphagous and invasive cotton bollworm Helicoverpa armigera. Since 2004, the Cry2Ab toxin has become widely used for controlling H. armigera, often used in combination with Cry1Ac to delay resistance evolution. Isolation of H. armigera and H. punctigera individuals heterozygous for Cry2Ab resistance in 2002 and 2004, respectively, allowed aspects of Cry2Ab resistance (level, fitness costs, genetic dominance, complementation tests to be characterised in both species. However, the gene identity and genetic changes conferring this resistance were unknown, as was the detailed Cry2Ab mode of action. No cross-resistance to Cry1Ac was observed in mutant lines. Biphasic linkage analysis of a Cry2Ab-resistant H. armigera family followed by exon-primed intron-crossing (EPIC marker mapping and candidate gene sequencing identified three independent resistance-associated INDEL mutations in an ATP-Binding Cassette (ABC transporter gene we named HaABCA2. A deletion mutation was also identified in the H. punctigera homolog from the resistant line. All mutations truncate the ABCA2 protein. Isolation of further Cry2Ab resistance alleles in the same gene from field H. armigera populations indicates unequal resistance allele frequencies and the potential for Bt resistance evolution. Identification of the gene involved in resistance as an ABC transporter of the A subfamily adds to the body of evidence on the crucial role this gene family plays in the mode of action of the Bt Cry toxins. The structural differences between the ABCA2, and that of the C subfamily required for Cry1Ac toxicity, indicate differences in the

  20. Insect Resistance to Bacillus thuringiensis Toxin Cry2Ab Is Conferred by Mutations in an ABC Transporter Subfamily A Protein

    Science.gov (United States)

    Tay, Wee Tek; Mahon, Rod J.; Heckel, David G.; Walsh, Thomas K.; Downes, Sharon; James, William J.; Lee, Sui-Fai; Reineke, Annette; Williams, Adam K.; Gordon, Karl H. J.

    2015-01-01

    The use of conventional chemical insecticides and bacterial toxins to control lepidopteran pests of global agriculture has imposed significant selection pressure leading to the rapid evolution of insecticide resistance. Transgenic crops (e.g., cotton) expressing the Bt Cry toxins are now used world wide to control these pests, including the highly polyphagous and invasive cotton bollworm Helicoverpa armigera. Since 2004, the Cry2Ab toxin has become widely used for controlling H. armigera, often used in combination with Cry1Ac to delay resistance evolution. Isolation of H. armigera and H. punctigera individuals heterozygous for Cry2Ab resistance in 2002 and 2004, respectively, allowed aspects of Cry2Ab resistance (level, fitness costs, genetic dominance, complementation tests) to be characterised in both species. However, the gene identity and genetic changes conferring this resistance were unknown, as was the detailed Cry2Ab mode of action. No cross-resistance to Cry1Ac was observed in mutant lines. Biphasic linkage analysis of a Cry2Ab-resistant H. armigera family followed by exon-primed intron-crossing (EPIC) marker mapping and candidate gene sequencing identified three independent resistance-associated INDEL mutations in an ATP-Binding Cassette (ABC) transporter gene we named HaABCA2. A deletion mutation was also identified in the H. punctigera homolog from the resistant line. All mutations truncate the ABCA2 protein. Isolation of further Cry2Ab resistance alleles in the same gene from field H. armigera populations indicates unequal resistance allele frequencies and the potential for Bt resistance evolution. Identification of the gene involved in resistance as an ABC transporter of the A subfamily adds to the body of evidence on the crucial role this gene family plays in the mode of action of the Bt Cry toxins. The structural differences between the ABCA2, and that of the C subfamily required for Cry1Ac toxicity, indicate differences in the detailed mode

  1. Modulating the function of ATP-binding cassette subfamily G member 2 (ABCG2) with inhibitor cabozantinib.

    Science.gov (United States)

    Zhang, Guan-Nan; Zhang, Yun-Kai; Wang, Yi-Jun; Barbuti, Anna Maria; Zhu, Xi-Jun; Yu, Xin-Yue; Wen, Ai-Wen; Wurpel, John N D; Chen, Zhe-Sheng

    2017-01-25

    Cabozantinib (XL184) is a small molecule tyrosine kinase receptor inhibitor, which targets c-Met and VEGFR2. Cabozantinib has been approved by the Food and Drug Administration to treat advanced medullary thyroid cancer and renal cell carcinoma. In the present study, we evaluated the ability of cabozantinib to modulate the function of the ATP-binding cassette subfamily G member 2 (ABCG2) by sensitizing cells that are resistant to ABCG2 substrate antineoplastic drugs. We used a drug-selected resistant cell line H460/MX20 and three ABCG2 stable transfected cell lines ABCG2-482-R2, ABCG2-482-G2, and ABCG2-482-T7, which overexpress ABCG2. Cabozantinib, at non-toxic concentrations (3 or 5μM), sensitized the ABCG2-overexpressing cells to mitoxantrone, SN-38, and topotecan. Our results indicate that cabozantinib reverses ABCG2-mediated multidrug resistance by antagonizing the drug efflux function of the ABCG2 transporter instead of downregulating its expression. The molecular docking analysis indicates that cabozantinib binds to the drug-binding site of the ABCG2 transporter. Overall, our findings demonstrate that cabozantinib inhibits the ABCG2 transporter function and consequently enhances the effect of the antineoplastic agents that are substrates of ABCG2. Cabozantinib may be a useful agent in anticancer treatment regimens for patients who are resistant to ABCG2 substrate drugs.

  2. Blockade of transient receptor potential cation channel subfamily V member 1 promotes regeneration after sciatic nerve injury

    Institute of Scientific and Technical Information of China (English)

    Fei Ren; Hong Zhang; Chao Qi; Mei-ling Gao; Hong Wang; Xia-qing Li

    2015-01-01

    The transient receptor potential cation channel subfamily V member 1 (TRPV1) provides the sensation of pain (nociception). However, it remains unknown whether TRPV1 is activated after peripheral nerve injury, or whether activation of TRPV1 affects neural regeneration. In the present study, we established rat models of unilateral sciatic nerve crush injury, with or without pretreatment with AMG517 (300 mg/kg), a TRPV1 antagonist, injected subcutaneously into the ipsilateral paw 60 minutes before injury. At 1 and 2 weeks after injury, we performed immuno-lfuorescence staining of the sciatic nerve at the center of injury, at 0.3 cm proximal and distal to the injury site, and in the dorsal root ganglia. Our results showed that Wallerian degeneration occurred distal to the injury site, and neurite outgrowth and Schwann cell regeneration occurred proximal to the injury. The number of regenerating myelinated and unmyelinated nerve clus-ters was greater in the AMG517-pretreated rats than in the vehicle-treated group, most notably 2 weeks after injury. TRPV1 expression in the injured sciatic nerve and ipsilateral dorsal root ganglia was markedly greater than on the contralateral side. Pretreatment with AMG517 blocked this effect. These data indicate that TRPV1 is activated or overexpressed after sciatic nerve crush injury, and that blockade of TRPV1 may accelerate regeneration of the injured sciatic nerve.

  3. TP0262 is a modulator of promoter activity of tpr Subfamily II genes of Treponema pallidum subsp. pallidum

    Science.gov (United States)

    Giacani, Lorenzo; Godornes, Charmie; Puray-Chavez, Maritza; Guerra-Giraldez, Cristina; Tompa, Martin; Lukehart, Sheila A.; Centurion-Lara, Arturo

    2009-01-01

    Transcriptional regulation in Treponema pallidum subsp. pallidum is poorly understood, primarily because this organism cannot be cultivated in vitro or genetically manipulated. We have recently shown a phase variation mechanism controlling transcription initiation of Subfamily II tpr (T. pallidum repeat) genes (tprE, tprG, and tprJ), a group of virulence factor candidates. Furthermore, the same study suggested that additional mechanisms might influence the level of transcription of these tprs. The T. pallidum genome sequence has revealed a few open reading frames (ORFs) with similarity to known bacterial transcription factors (TFs), including four catabolite activator protein (CAP) homologs. In this work, sequences matching the E. coli cAMP receptor protein (CRP) binding motif were identified in silico upstream of tprE, tprG, and tprJ. Using elecrophoretic mobility shift assay (EMSA) and DNaseI footprinting assay, recombinant TP0262, a T. pallidum CRP homolog, was shown to bind specifically to amplicons obtained from the tpr promoters containing putative CRP binding motifs. Using a heterologous reporter system, binding of TP0262 to these promoters was shown to either increase (tprE and tprJ) or decrease (tprG) tpr promoter activity. This is the first characterization of a T. pallidum transcriptional modulator which influences tpr promoter activity. PMID:19432808

  4. Phylogenetic relationships, character evolution, and biogeography of the subfamily Lygosominae (Reptilia: Scincidae) inferred from mitochondrial DNA sequences.

    Science.gov (United States)

    Honda, M; Ota, H; Kobayashi, M; Nabhitabhata, J; Yong, H S; Hikida, T

    2000-06-01

    Phylogenetic relationships among the lygosomine skinks were inferred from 1249 base positions of mitochondrial DNA sequences of 12S and 16S rRNA genes. The monophyly of this subfamily was confirmed and the presence of five distinct infrasubfamilial lineages detected. Of these, the Sphenomorphus group appears to have diverged first, followed by the Lygosoma and Egernia groups in order, leaving the Eugongylus and Mabuya groups as sister groups. Our results did not support monophyly of the Mabuya group sensu lato (i.e., an assemblage of the Lygosoma, Egernia, and Mabuya groups), for which a number of morphological and karyological studies demonstrated a considerable similarity. Our results also contradict the previous hypothesis, formulated on the basis of morphological and immunological data, which argued for the sister relationship between the Egernia and the Eugongylus groups. Morphological and karyological characters used to define the Mabuya group (sensu lato) may actually represent plesiomorphic states. The phylogenetic diversity of lygosomine skinks in the Australian region appears to have increased through multiple colonizations from Southeast Asia.

  5. Linear array of conserved sequence motifs to discriminate protein subfamilies: study on pyridine nucleotide-disulfide reductases

    Directory of Open Access Journals (Sweden)

    De Las Rivas Javier

    2007-03-01

    Full Text Available Abstract Background The pyridine nucleotide disulfide reductase (PNDR is a large and heterogeneous protein family divided into two classes (I and II, which reflect the divergent evolution of its characteristic disulfide redox active site. However, not all the PNDR members fit into these categories and this suggests the need of further studies to achieve a more comprehensive classification of this complex family. Results A workflow to improve the clusterization of protein families based on the array of linear conserved motifs is designed. The method is applied to the PNDR large family finding two main groups, which correspond to PNDR classes I and II. However, two other separate protein clusters, previously classified as class I in most databases, are outgrouped: the peroxide reductases (NAOX, NAPE and the type II NADH dehydrogenases (NDH-2. In this way, two novel PNDR classes III and IV for NAOX/NAPE and NDH-2 respectively are proposed. By knowledge-driven biochemical and functional data analyses done on the new class IV, a linear array of motifs putatively related to Cu(II-reductase activity is detected in a specific subset of NDH-2. Conclusion The results presented are a novel contribution to the classification of the complex and large PNDR protein family, supporting its reclusterization into four classes. The linear array of motifs detected within the class IV PNDR subfamily could be useful as a signature for a particular subgroup of NDH-2.

  6. TP0262 is a modulator of promoter activity of tpr Subfamily II genes of Treponema pallidum ssp. pallidum.

    Science.gov (United States)

    Giacani, Lorenzo; Godornes, Charmie; Puray-Chavez, Maritza; Guerra-Giraldez, Cristina; Tompa, Martin; Lukehart, Sheila A; Centurion-Lara, Arturo

    2009-06-01

    Transcriptional regulation in Treponema pallidum ssp. pallidum is poorly understood, primarily because this organism cannot be cultivated in vitro or genetically manipulated. We have recently shown a phase variation mechanism controlling transcription initiation of Subfamily II tpr (T. pallidumrepeat) genes (tprE, tprG and tprJ), a group of virulence factor candidates. Furthermore, the same study suggested that additional mechanisms might influence the level of transcription of these tprs. The T. pallidum genome sequence has revealed a few open reading frames with similarity to known bacterial transcription factors, including four catabolite activator protein homologues. In this work, sequences matching the Escherichia coli cAMP receptor protein (CRP) binding motif were identified in silico upstream of tprE, tprG and tprJ. Using elecrophoretic mobility shift assay and DNaseI footprinting assay, recombinant TP0262, a T. pallidum CRP homologue, was shown to bind specifically to amplicons obtained from the tpr promoters containing putative CRP binding motifs. Using a heterologous reporter system, binding of TP0262 to these promoters was shown to either increase (tprE and tprJ) or decrease (tprG) tpr promoter activity. This is the first characterization of a T. pallidum transcriptional modulator that influences tpr promoter activity.

  7. Differential manifolds

    CERN Document Server

    Kosinski, Antoni A

    2007-01-01

    The concepts of differential topology form the center of many mathematical disciplines such as differential geometry and Lie group theory. Differential Manifolds presents to advanced undergraduates and graduate students the systematic study of the topological structure of smooth manifolds. Author Antoni A. Kosinski, Professor Emeritus of Mathematics at Rutgers University, offers an accessible approach to both the h-cobordism theorem and the classification of differential structures on spheres.""How useful it is,"" noted the Bulletin of the American Mathematical Society, ""to have a single, sho

  8. Estrous Cycle and Gestational Age-Dependent Expression of Members of the Interleukin-36 Subfamily in a Semi-Allogeneic Model of Infected and Non-Infected Murine Pregnancy

    Science.gov (United States)

    Murrieta-Coxca, José Martin; Gómez-Chávez, Fernando; Baeza-Martínez, Damariz Adriana; Cancino-Diaz, Mario Eugenio; Cancino-Diaz, Juan Carlos; Pérez-Tapia, Sonia Mayra; Reyes-Maldonado, Elba; Rodríguez-Martínez, Sandra

    2016-01-01

    The IL-36 subfamily is a recently described group of cytokines with pro-inflammatory behavior, comprising three agonists (α, β, and γ), its receptor (R), and one antagonist (Ra). The expression and function of IL-36 subfamily members in the estrous cycle in healthy and infected pregnancy has not been described. We evaluated mRNA and protein expression of IL-36 family members during the estrous cycle, implantation, fetal development, and post-labor periods in a model of allogenic pregnancy in mice. We also explored the ability of Listeria monocytogenes to modulate the expression of IL-36 subfamily members during pregnancy. Expression of IL-36 subfamily members showed different expression during the estrous cycle and pregnancy but was induced at estrous, 16.5 days post coitum (dpc), 18.5 dpc, and labor. IL-36 subfamily members showed a characteristic distribution in the glandular epithelium, perimetrium, myometrium, and stratum vasculare. Infection with L. monocytogenes during pregnancy induced strong production of IL-36 subfamily members, an observation that correlated with an increasing prevalence of fetal loss. In conclusion, IL-36 agonists showed specific patterns of mRNA and protein expression that might suggest functional specialization or specific target cells. Infection with L. monocytogenes during pregnancy induced strong production of IL-36 subfamily members. PMID:27713746

  9. Estrous cycle and gestational age-dependent expression of members of the interleukin-36 subfamily in a semi-allogeneic model of infected and non-infected murine pregnancy

    Directory of Open Access Journals (Sweden)

    José Martin Murrieta Coxca

    2016-09-01

    Full Text Available The IL-36 subfamily is a recently described group of cytokines with pro-inflammatory behavior, comprising three agonists (α, β and γ, its receptor (R and one antagonist (Ra. The expression and function of IL-36 subfamily members in the estrous cycle in healthy and infected pregnancy have not been described. We evaluated mRNA and protein expression of IL-36 family members during the estrous cycle, implantation, fetal development and post-labor periods in a model of allogenic pregnancy in mice. We also explored the ability of Listeria monocytogenes to modulate expression of IL-36 subfamily members during pregnancy. Expression of IL-36 subfamily members showed different expression during the estrous cycle and pregnancy, but was induced at estrous, 16.5 days post coitum (dpc, 18.5 dpc and labor. IL-36 subfamily members showed a characteristic distribution in the glandular epithelium, perimetrium, myometrium, and stratum vasculare. Infection with Listeria monocytogenes during pregnancy induced strong production of IL-36 subfamily members, an observation that correlated with an increasing prevalence of fetal loss. Conclusions: IL-36 agonists showed specific patterns of mRNA and protein expression that might suggest functional specialization or specific target cells. Infection with Listeria monocytogenes during pregnancy induced strong production of IL-36 subfamily members.

  10. The Na+/H+ exchanger, NHE1, differentially regulates mitogen-activated protein kinase subfamilies after osmotic shrinkage in Ehrlich Lettre Ascites cells

    DEFF Research Database (Denmark)

    Petersen, Stine Helene Falsig; Rasmussen, Maria; Darborg, Barbara Vasek;

    2007-01-01

    Osmotic stress modulates mitogen activated protein kinase (MAPK) activities, leading to altered gene transcription and cell death/survival balance, however, the mechanisms involved are incompletely elucidated. Here, we show, using a combination of biochemical and molecular biology approaches......, that three MAPKs exhibit unique interrelationships with the Na(+)/H(+) exchanger, NHE1, after osmotic cell shrinkage: Extracellular Signal Regulated Kinase (ERK1/2) is inhibited in an NHE1-dependent, pH(i)-independent manner, c-Jun N-terminal kinase (JNK1/2) is stimulated, in part through NHE1-mediated...

  11. Differential expression of human cytochrome P450 enzymes from the CYP3A subfamily in the brains of alcoholic subjects and drug-free controls.

    Science.gov (United States)

    Booth Depaz, Iris M; Toselli, Francesca; Wilce, Peter A; Gillam, Elizabeth M J

    2013-06-01

    Cytochrome P450 enzymes are responsible for the metabolism of most commonly used drugs. Among these enzymes, CYP3A forms mediate the clearance of around 40-50% of drugs and may also play roles in the biotransformation of endogenous compounds. CYP3A forms are expressed both in the liver and extrahepatically. However, little is known about the expression of CYP3A proteins in specific regions of the human brain. In this study, form-selective antibodies raised to CYP3A4 and CYP3A5 were used to characterize the expression of these forms in the human brain. Both CYP3A4 and CYP3A5 immunoreactivity were found to varying extents in the microsomal fractions of cortex, hippocampus, basal ganglia, amygdala, and cerebellum. However, only CYP3A4 expression was observed in the mitochondrial fractions of these brain regions. N-terminal sequencing confirmed the principal antigen detected by the anti-CYP3A4 antibody in cortical microsomes to be CYP3A4. Immunohistochemical analysis revealed that CYP3A4 and CYP3A5 expression was primarily localized in the soma and axonal hillock of neurons and varied according to cell type and cell layer within brain regions. Finally, analysis of the frontal cortex of chronic alcohol abusers revealed elevated expression of CYP3A4 in microsomal but not mitochondrial fractions; CYP3A5 expression was unchanged. The site-specific expression of CYP3A4 and CYP3A5 in the human brain may have implications for the role of these enzymes in both normal brain physiology and the response to drugs.

  12. Checklist of the subfamily Adoncholaiminae Gerlach and Riemann, 1974 (Nematoda: Oncholaimida: Oncholaimidae) of the world: genera, species, distribution, and reference list for taxonomists and ecologists

    Science.gov (United States)

    2016-01-01

    Abstract Background Adoncholaiminae is one of the seven subfamilies in the free-living aquatic nematode family Oncholaimidae. Nematodes in Adoncholaiminae are found from various water environment of the world. However, a checklist of all Adoncholaiminae species including full literature, especially information of experimental (not taxonomic) works, has not been updated for more than 40 years. New information A revised checklist of the subfamily Adoncholaiminae of the world is provided. It contains 31 valid and 13 invalid species names in four genera with synonyms, collection records, and full literature from 1860's to 2015 for each species. A literature survey of total 477 previous papers was conducted in this work, and 362 of them are newly added to checklist. PMID:26929708

  13. The discovery of phiAGATE, a novel phage infecting Bacillus pumilus, leads to new insights into the phylogeny of the subfamily Spounavirinae.

    Directory of Open Access Journals (Sweden)

    Jakub Barylski

    Full Text Available The Bacillus phage phiAGATE is a novel myovirus isolated from the waters of Lake Góreckie (a eutrophic lake in western Poland. The bacteriophage infects Bacillus pumilus, a bacterium commonly observed in the mentioned reservoir. Analysis of the phiAGATE genome (149844 base pairs resulted in 204 predicted protein-coding sequences (CDSs, of which 53 could be functionally annotated. Further investigation revealed that the bacteriophage is a member of a previously undescribed cluster of phages (for the purposes of this study we refer to it as "Bastille group" within the Spounavirinae subfamily. Here we demonstrate that these viruses constitute a distinct branch of the Spounavirinae phylogenetic tree, with limited similarity to phages from the Twortlikevirus and Spounalikevirus genera. The classification of phages from the Bastille group into any currently accepted genus proved extremely difficult, prompting concerns about the validity of the present taxonomic arrangement of the subfamily.

  14. Differential meadows

    NARCIS (Netherlands)

    J.A. Bergstra; A. Ponse

    2008-01-01

    A meadow is a zero totalised field (0^{-1}=0), and a cancellation meadow is a meadow without proper zero divisors. In this paper we consider differential meadows, i.e., meadows equipped with differentiation operators. We give an equational axiomatization of these operators and thus obtain a finite b

  15. Comparative analysis of serine/arginine-rich proteins across 27 eukaryotes: insights into sub-family classification and extent of alternative splicing.

    Directory of Open Access Journals (Sweden)

    Dale N Richardson

    Full Text Available Alternative splicing (AS of pre-mRNA is a fundamental molecular process that generates diversity in the transcriptome and proteome of eukaryotic organisms. SR proteins, a family of splicing regulators with one or two RNA recognition motifs (RRMs at the N-terminus and an arg/ser-rich domain at the C-terminus, function in both constitutive and alternative splicing. We identified SR proteins in 27 eukaryotic species, which include plants, animals, fungi and "basal" eukaryotes that lie outside of these lineages. Using RNA recognition motifs (RRMs as a phylogenetic marker, we classified 272 SR genes into robust sub-families. The SR gene family can be split into five major groupings, which can be further separated into 11 distinct sub-families. Most flowering plants have double or nearly double the number of SR genes found in vertebrates. The majority of plant SR genes are under purifying selection. Moreover, in all paralogous SR genes in Arabidopsis, rice, soybean and maize, one of the two paralogs is preferentially expressed throughout plant development. We also assessed the extent of AS in SR genes based on a splice graph approach (http://combi.cs.colostate.edu/as/gmap_SRgenes. AS of SR genes is a widespread phenomenon throughout multiple lineages, with alternative 3' or 5' splicing events being the most prominent type of event. However, plant-enriched sub-families have 57%-88% of their SR genes experiencing some type of AS compared to the 40%-54% seen in other sub-families. The SR gene family is pervasive throughout multiple eukaryotic lineages, conserved in sequence and domain organization, but differs in gene number across lineages with an abundance of SR genes in flowering plants. The higher number of alternatively spliced SR genes in plants emphasizes the importance of AS in generating splice variants in these organisms.

  16. Two new mite species of the subfamily Harpirhynchinae Dubinin, 1957 (Acariformes: Harpirhynchidae), parasites of the passerine birds (Aves: Passeriformes) in Australia and South Asia.

    Science.gov (United States)

    Bochkov, Andre V; Klompen, Hans

    2015-09-01

    Two new mite species of the subfamily Harpirhynchinae Dubinin, 1957 (Acariformes: Harpirhynchidae) are described from passerine birds (Aves: Passeriformes): Harpirhynchoides artamus n. sp. from Artamus fuscus Vieillot (Artamidae) from an unknown locality in South Asia and Neharpyrhynchus domrowi n. sp. from three host species of the family Meliphagidae, Acanthorhynchus tenuirostris (Latham) (type-host) from Australia (New South Walles), Ptiloprora perstriata (De Vis) and Myzomela rosenbergii Schlegel from Papua New Guinea.

  17. The expression of T-cell receptor Vβ subfamily in hepatitis B virus-related acute-on-chronic liver failure patients and its clinical significance

    Institute of Scientific and Technical Information of China (English)

    施文娟

    2014-01-01

    Objective To investigate the expression and clinical significance of T-cell receptor(TCR)Vβsubfamily in hepatitis B virus(HBV)-related acute-on-chronic liverfailure(HBV-ACLF)patients.Methods Twenty-eight patients with HBV-ACLF(HBV-ACLF group)and 32patients with chronic hepatitis B flare(CHB-F group),who were treated in The Second People’s Hospital from

  18. Genetic association of aromatic hydrocarbon receptor (AHR) and cytochrome P450, family 1, subfamily A, polypeptide 1 (CYP1A1) polymorphisms with dioxin blood concentrations among pregnant Japanese women

    OpenAIRE

    Kobayashi, Sumitaka; Sata, Fumihiro; Sasaki, Seiko; Ban, Susumu; Miyashita, Chihiro; Okada, Emiko; Limpar, Mariko; Yoshioka, Eiji; Kajiwara, Jumboku; TODAKA, Takashi; Saijo, Yasuaki; Kishi, Reiko

    2013-01-01

    Dioxins are metabolized by cytochrome P450, family 1 (CYP1) via the aromatic hydrocarbon receptor (AHR). We determined whether different blood dioxin concentrations are associated with polymorphisms in AHR (dbSNP ID: rs2066853), AHR repressor (AHRR; rs2292596), CYP1 subfamily A polypeptide 1 (CYP1A1; rs4646903 and rs1048963), CYP1 subfamily A polypeptide 2 (CYP1A2; rs762551), and CYP1 subfamily B polypeptide 1 (CYP1B1; rs1056836) in pregnant Japanese women. These six polymorphisms were detect...

  19. Differential equations

    CERN Document Server

    Barbu, Viorel

    2016-01-01

    This textbook is a comprehensive treatment of ordinary differential equations, concisely presenting basic and essential results in a rigorous manner. Including various examples from physics, mechanics, natural sciences, engineering and automatic theory, Differential Equations is a bridge between the abstract theory of differential equations and applied systems theory. Particular attention is given to the existence and uniqueness of the Cauchy problem, linear differential systems, stability theory and applications to first-order partial differential equations. Upper undergraduate students and researchers in applied mathematics and systems theory with a background in advanced calculus will find this book particularly useful. Supplementary topics are covered in an appendix enabling the book to be completely self-contained.

  20. A review of the mite subfamily Harpirhynchinae (Acariformes: Harpirhynchidae)--parasites of New World birds (Aves: Neognathae).

    Science.gov (United States)

    Bochkov, Andre V; OConnor, Barry M; Klompen, Hans

    2015-09-30

    Mites of the subfamily Harpirhynchinae (Acariformes: Cheyletoidea: Harpirhynchidae) associated with neognathous birds (Aves: Neognathae) in the New World are revised. In all, 68 species in 8 genera are recorded. Among them, 27 new species and 1 new genus are described as new for science: Harpyrhynchoides gallowayi Bochkov, OConnor and Klompen sp. nov. from Columba livia (Columbiformes: Columbidae) from Canada (Manitoba), H. zenaida Bochkov, OConnor and Klompen sp. nov. from Zenaida macroura (Columbiformes: Columbidae) from USA (Michigan), H. calidris Bochkov, OConnor and Klompen sp. nov. from Calidris minutilla (Charadriiformes: Scolopacidae) from USA (Kansas), H. actitis Bochkov, OConnor and Klompen sp. nov. from Actitis macularius (Charadriiformes: Scolopacidae) from Canada (British Columbia), H. charadrius Bochkov, OConnor and Klompen sp. nov. from Charadrius vociferus (Charadriiformes: Charadriidae) from USA (Texas), H. pluvialis Bochkov, OConnor and Klompen sp. nov. from Pluvialis dominica (Charadriiformes: Charadriidae) from USA (Ohio), H. bubulcus Bochkov, OConnor and Klompen sp. nov. from Bubulcus ibis (Pelecaniformes: Ardeidae) from USA (Florida), H. ixobrychus Bochkov, OConnor and Klompen sp. nov. from Ixobrychus exilis (Pelecaniformes: Ardeidae) from USA (Michigan), H. puffinus Mertins sp. nov. from Puffinus gravis (Procellariformes: Procellariidae) from USA (Florida), H. megascops Bochkov, OConnor and Klompen sp. nov. from Megascops asio (Strigiformes: Strigidae) from USA (Michigan), H. athene Bochkov, OConnor and Klompen sp. nov. from Athene canicularia (Strigiformes: Strigidae) from USA (Texas), H. coccyzus Bochkov, OConnor and Klompen sp. nov. from Coccyzus americanus (Cuculiformes: Cuculidae) from USA (Michigan), H. crotophaga Bochkov, OConnor and Klompen sp. nov. from Crotophaga ani (Cuculiformes: Cuculidae) from Suriname; Crassacarus Bochkov, OConnor and Klompen, gen. nov.: Crassacarus alexfaini Bochkov, OConnor and Klompen sp. nov. (type of genus

  1. Crystal structure of a raw-starch-degrading bacterial α-amylase belonging to subfamily 37 of the glycoside hydrolase family GH13

    Science.gov (United States)

    Liu, Yanhong; Yu, Jigang; Li, Fudong; Peng, Hui; Zhang, Xuecheng; Xiao, Yazhong; He, Chao

    2017-01-01

    Subfamily 37 of the glycoside hydrolase family GH13 was recently established on the basis of the discovery of a novel α-amylase, designated AmyP, from a marine metagenomic library. AmyP exhibits raw-starch-degrading activity and consists of an N-terminal catalytic domain and a C-terminal starch-binding domain. To understand this newest subfamily, we determined the crystal structure of the catalytic domain of AmyP, named AmyPΔSBD, complexed with maltose, and the crystal structure of the E221Q mutant AmyPΔSBD complexed with maltotriose. Glu221 is one of the three conserved catalytic residues, and AmyP is inactivated by the E221Q mutation. Domain B of AmyPΔSBD forms a loop that protrudes from domain A, stabilizes the conformation of the active site and increases the thermostability of the enzyme. A new calcium ion is situated adjacent to the -3 subsite binding loop and may be responsible for the increased thermostability of the enzyme after the addition of calcium. Moreover, Tyr36 participates in both stacking and hydrogen bonding interactions with the sugar motif at subsite -3. This work provides the first insights into the structure of α-amylases belonging to subfamily 37 of GH13 and may contribute to the rational design of α-amylase mutants with enhanced performance in biotechnological applications. PMID:28303907

  2. Morphological "primary homology" and expression of AG-subfamily MADS-box genes in pines, podocarps, and yews.

    Science.gov (United States)

    Englund, Marie; Carlsbecker, Annelie; Engström, Peter; Vergara-Silva, Francisco

    2011-01-01

    The morphological variation among reproductive organs of extant gymnosperms is remarkable, especially among conifers. Several hypotheses concerning morphological homology between various conifer reproductive organs have been put forward, in particular in relation to the pine ovuliferous scale. Here, we use the expression patterns of orthologs of the ABC-model MADS-box gene AGAMOUS (AG) for testing morphological homology hypotheses related to organs of the conifer female cone. To this end, we first developed a tailored 3'RACE procedure that allows reliable amplification of partial sequences highly similar to gymnosperm-derived members of the AG-subfamily of MADS-box genes. Expression patterns of two novel conifer AG orthologs cloned with this procedure-namely PodAG and TgAG, obtained from the podocarp Podocarpus reichei and the yew Taxus globosa, respectively-are then further characterized in the morphologically divergent female cones of these species. The expression patterns of PodAG and TgAG are compared with those of DAL2, a previously discovered Picea abies (Pinaceae) AG ortholog. By treating the expression patterns of DAL2, PodAG, and TgAG as character states mapped onto currently accepted cladogram topologies, we suggest that the epimatium-that is, the podocarp female cone organ previously postulated as a "modified" ovuliferous scale-and the canonical Pinaceae ovuliferous scale can be legitimally conceptualized as "primary homologs." Character state mapping for TgAG suggests in turn that the aril of Taxaceae should be considered as a different type of organ. This work demonstrates how the interaction between developmental-genetic data and formal cladistic theory could fruitfully contribute to gymnosperm systematics.

  3. The ZNF75 zinc finger gene subfamily: Isolation and mapping of the four members in humans and great apes

    Energy Technology Data Exchange (ETDEWEB)

    Villa, A.; Strina, D.; Frattini, A. [Consiglio Nazionale delle Ricerche, Milan (Italy)] [and others

    1996-07-15

    We have previously reported the characterization of the human ZNF75 gene located on Xq26, which has only limited homology (less than 65%) to other ZF genes in the databases. Here, we describe three human zinc finger genes with 86 to 95% homology to ZNF75 at the nucleotide level, which represent all the members of the human ZNF75 subfamily. One of these, ZNF75B, is a pseudogene mapped to chromosome 12q13. The other two, ZNF75A and ZNF75C, maintain on ORF in the sequenced region, and at least the latter is expressed in the U937 cell line. They were mapped to chromosomes 16 and 11, respectively. All these genes are conserved in chimpanzees, gorillas, and orangutans. The ZNF75B homologue is a pseudogene in all three great apes, and in chimpanzee it is located on chromosome 10 (phylogenetic XII), at p13 (corresponding to the human 12q13). The chimpanzee homologue of ZNF75 is also located on the Xq26 chromosome, in the same region, as detected by in situ hybridization. As expected, nucleotide changes were clearly more abundant between human and organutan than between human and chimpanzee or gorilla homologues. Members of the same class were more similar to each other than to the other homologues within the same species. This suggests that the duplication and/or retrotranscription events occurred in a common ancestor long before great ape speciation. This, together with the existance of at least two genes in cows and horses, suggests a relatively high conservation of this gene family. 20 refs., 5 figs., 1 tab.

  4. A novel fractal approach for predicting G-protein-coupled receptors and their subfamilies with support vector machines.

    Science.gov (United States)

    Nie, Guoping; Li, Yong; Wang, Feichi; Wang, Siwen; Hu, Xuehai

    2015-01-01

    G-protein-coupled receptors (GPCRs) are seven membrane-spanning proteins and regulate many important physiological processes, such as vision, neurotransmission, immune response and so on. GPCRs-related pathways are the targets of a large number of marketed drugs. Therefore, the design of a reliable computational model for predicting GPCRs from amino acid sequence has long been a significant biomedical problem. Chaos game representation (CGR) reveals the fractal patterns hidden in protein sequences, and then fractal dimension (FD) is an important feature of these highly irregular geometries with concise mathematical expression. Here, in order to extract important features from GPCR protein sequences, CGR algorithm, fractal dimension and amino acid composition (AAC) are employed to formulate the numerical features of protein samples. Four groups of features are considered, and each group is evaluated by support vector machine (SVM) and 10-fold cross-validation test. To test the performance of the present method, a new non-redundant dataset was built based on latest GPCRDB database. Comparing the results of numerical experiments, the group of combined features with AAC and FD gets the best result, the accuracy is 99.22% and Matthew's correlation coefficient (MCC) is 0.9845 for identifying GPCRs from non-GPCRs. Moreover, if it is classified as a GPCR, it will be further put into the second level, which will classify a GPCR into one of the five main subfamilies. At this level, the group of combined features with AAC and FD also gets best accuracy 85.73%. Finally, the proposed predictor is also compared with existing methods and shows better performances.

  5. Stereochemistry of Fuscumol and Fuscumol Acetate Influences Attraction of Longhorned Beetles (Coleoptera: Cerambycidae) of the Subfamily Lamiinae.

    Science.gov (United States)

    Hughes, G P; Meier, L R; Zou, Y; Millar, J G; Hanks, L M; Ginzel, M D

    2016-10-01

    The chemical structures of aggregation-sex pheromones of longhorned beetles (Coleoptera: Cerambycidae) are often conserved among closely related taxa. In the subfamily Lamiinae, adult males and females of several species are attracted by racemic blends of (E)-6,10-dimethyl-5,9-undecadien-2-ol (termed fuscumol) and the structurally related (E)-6,10-dimethyl-5,9-undecadien-2-yl acetate (fuscumol acetate). Both compounds have a chiral center, so each can exist in two enantiomeric forms. Males of many species of longhorned beetles only produce one stereoisomer of each pheromone component, and attraction may be reduced by the presence of stereoisomers that are not produced by a particular species. In a previous publication, analysis of headspace volatiles of adult beetles of the lamiine species Astyleiopus variegatus (Haldeman) revealed that males sex-specifically produced (S)-fuscumol and (S)-fuscumol acetate. Here, we describe field trials which tested attraction of this species to single enantiomers of fuscumol and fuscumol acetate, or to blends of enantiomers. We confirmed attraction of A. variegatus to its species-specific blend, but during the course of the trials, found that several other species also were attracted. These included Aegomorphus modestus (Gyllenhall), attracted to (S)-fuscumol acetate; Astylidius parvus (LeConte), attracted to (R)-fuscumol; Astylopsis macula (Say), attracted to (S)-fuscumol; and Graphisurus fasciatus (DeGeer), attracted to a blend of (R)-fuscumol and (R)-fuscumol acetate. These results suggest that chirality may be important in the pheromone chemistry of lamiines, and that specific stereoisomers or mixtures of stereoisomers are likely produced by each species.

  6. Identification and characterization of RBEL1 subfamily of GTPases in the Ras superfamily involved in cell growth regulation.

    Science.gov (United States)

    Montalbano, JoAnne; Lui, Ki; Sheikh, M Saeed; Huang, Ying

    2009-07-03

    Recently, we reported the identification of a novel gene named RBEL1 (Rab-like protein 1) and characterized its two encoded isoforms, RBEL1A and RBEL1B, that function as novel GTPases of Ras superfamily. Here we report the identification of two additional splice variants of RBEL1 that we have named RBEL1C and -D. All four RBEL1 isoforms (A, B, C, and D) have identical N termini harboring the Rab-like GTPase domains but contain variable C termini. Although all isoforms can be detected in both cytoplasm and nucleus, RBEL1A is predominantly cytoplasmic, whereas RBEL1B is mostly nuclear. RBEL1C and -D, by contrast, are evenly distributed between the cytoplasm and nucleus. Furthermore, all four RBEL1 proteins are also capable of associating with cellular membrane. The RBEL1 proteins also exhibit a unique nucleotide-binding potential and, whereas the larger A and B isoforms are mainly GTP-bound, the smaller C and D variants bind to both GTP and GDP. Furthermore, a regulatory region at amino acid position 236-302 immediately adjacent to the GTP-binding domain is important for GTP-binding potential of RBEL1A, because deletion of this region converts RBEL1A from predominantly GTP-bound to GDP-bound. RBEL1 knockdown via RNA interference results in marked cell growth suppression, which is associated with morphological and biochemical features of apoptosis as well as inhibition of extracellular signal-regulated kinase phosphorylation. Taken together, our results indicate that RBEL1 proteins are linked to cell growth and survival and possess unique biochemical, cellular, and functional characteristics and, therefore, appear to form a novel subfamily of GTPases within the Ras superfamily.

  7. The Hevea brasiliensis XIP aquaporin subfamily: genomic, structural and functional characterizations with relevance to intensive latex harvesting.

    Science.gov (United States)

    Lopez, David; Amira, Maroua Ben; Brown, Daniel; Muries, Beatriz; Brunel-Michac, Nicole; Bourgerie, Sylvain; Porcheron, Benoit; Lemoine, Remi; Chrestin, Hervé; Mollison, Ewan; Di Cola, Alessandra; Frigerio, Lorenzo; Julien, Jean-Louis; Gousset-Dupont, Aurélie; Fumanal, Boris; Label, Philippe; Pujade-Renaud, Valérie; Auguin, Daniel; Venisse, Jean-Stéphane

    2016-07-01

    X-Intrinsic Proteins (XIP) were recently identified in a narrow range of plants as a full clade within the aquaporins. These channels reportedly facilitate the transport of a wide range of hydrophobic solutes. The functional roles of XIP in planta remain poorly identified. In this study, we found three XIP genes (HbXIP1;1, HbXIP2;1 and HbXIP3;1) in the Hevea brasiliensis genome. Comprehensive bioinformatics, biochemical and structural analyses were used to acquire a better understanding of this AQP subfamily. Phylogenetic analysis revealed that HbXIPs clustered into two major groups, each distributed in a specific lineage of the order Malpighiales. Tissue-specific expression profiles showed that only HbXIP2;1 was expressed in all the vegetative tissues tested (leaves, stem, bark, xylem and latex), suggesting that HbXIP2;1 could take part in a wide range of cellular processes. This is particularly relevant to the rubber-producing laticiferous system, where this isoform was found to be up-regulated during tapping and ethylene treatments. Furthermore, the XIP transcriptional pattern is significantly correlated to latex production level. Structural comparison with SoPIP2;1 from Spinacia oleracea species provides new insights into the possible role of structural checkpoints by which HbXIP2;1 ensures glycerol transfer across the membrane. From these results, we discuss the physiological involvement of glycerol and HbXIP2;1 in water homeostasis and carbon stream of challenged laticifers. The characterization of HbXIP2;1 during rubber tree tapping lends new insights into molecular and physiological response processes of laticifer metabolism in the context of latex exploitation.

  8. Differential games

    CERN Document Server

    Friedman, Avner

    2006-01-01

    This volume lays the mathematical foundations for the theory of differential games, developing a rigorous mathematical framework with existence theorems. It begins with a precise definition of a differential game and advances to considerations of games of fixed duration, games of pursuit and evasion, the computation of saddle points, games of survival, and games with restricted phase coordinates. Final chapters cover selected topics (including capturability and games with delayed information) and N-person games.Geared toward graduate students, Differential Games will be of particular interest

  9. Differential topology

    CERN Document Server

    Mukherjee, Amiya

    2015-01-01

    This book presents a systematic and comprehensive account of the theory of differentiable manifolds and provides the necessary background for the use of fundamental differential topology tools. The text includes, in particular, the earlier works of Stephen Smale, for which he was awarded the Fields Medal. Explicitly, the topics covered are Thom transversality, Morse theory, theory of handle presentation, h-cobordism theorem, and the generalised Poincaré conjecture. The material is the outcome of lectures and seminars on various aspects of differentiable manifolds and differential topology given over the years at the Indian Statistical Institute in Calcutta, and at other universities throughout India. The book will appeal to graduate students and researchers interested in these topics. An elementary knowledge of linear algebra, general topology, multivariate calculus, analysis, and algebraic topology is recommended.

  10. Revision of the Oriental subfamily Heteropteryginae Kirby, 1896, with a re-arrangement of the family Heteropterygidae and the descriptions of five new species of Haaniella Kirby, 1904. (Phasmatodea: Areolatae: Heteropterygidae).

    Science.gov (United States)

    Hennemann, Frank H; Conle, Oskar V; Brock, Paul D; Seow-Choen, Francis

    2016-09-01

    established for the three basal genera Tisamenus Stål, 1875, Ilocano Rehn & Rehn, 1939 and Hoploclonia Stål, 1875 all of which were placed in Eubulidini by Zompro (2004). The latter genus differs from the other two genera by the morphology of the female genitalia, which is unique amongst the entire family. Three generic groups are recognized within Obrimini, the Obrimus-group, Stenobrimus-group and Theramenes-group. Keys are presented to distinguish between the three tribes now contained in the Obriminae, i.e. Obrimini, Tisamenini n. trib. and Miroceramiini. The genus Hennobrimus Conle, 2006 is synonymised with Mearnsiana Rehn & Rehn, 1939, based on the fact that the type-species of both genera are conspecific (n. syn.). Hennobrimus hennemanni Conle, 2006, the type-species of Hennobrimus, and Trachyaretaon manobo Lit & Eusebio, 2005 are synonymised with Mearnsiana bullosa Rehn & Rehn, 1939, the type-species of Mearnsiana (n. syn.). Theramenes dromedarius Stål, 1877 from the Philippines is removed from synonymy with the Wallacean Theramenes olivaceus (Westwood, 1859) and re-established as a valid species (rev. stat.).        The subfamily Heteropteryginae Kirby, 1896 is revised at the species-level and a new diagnosis is presented. Keys to the two genera and all 16 known species are provided along with new descriptions, differential diagnoses, lists of examined material, detailed information on the known distributions, measurements and illustrations of the insects and eggs. The intra-subfamiliar and intra-generic relationships are discussed and a cladogram is presented. Heteropteryginae contains two genera: Heteropteryx Gray, 1835 (Type-species: Phasma dilatatum Parkinson, 1798) and Haaniella Kirby, 1896 (Type-species: Phasma (Heteropteryx) muelleri de Haan, 1842). The distribution of this subfamily is restricted to Sundaland with the exception of a single species that is found in Vietnam. All other species are distributed in Borneo, Sumatra, the Mentawai Islands

  11. Differential Krull dimension in differential polynomial extensions

    OpenAIRE

    Smirnov, Ilya

    2011-01-01

    We investigate the differential Krull dimension of differential polynomials over a differential ring. We prove a differential analogue of Jaffard's Special Chain Theorem and show that differential polynomial extensions of certain classes of differential rings have no anomaly of differential Krull dimension.

  12. APL患者外周血TCR V α亚家族T细胞分布和增殖特点%Distribution and clonality of peripheral blood TCR Vαsubfamily T cells in patients with acute promyelocytic leukemia

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Objective: To investigate the distribution and clonality of TCR Vc subfamily T cells in patients with acute promyelocytic leukemia (APL). Methods: The complementary determining region 3 (CDR3) of TCR Vα 29 subfamily genes in peripheral blood mononuclear cells from 9 APL patients were amplified using RT-PCR. The positive products were further analyzed to identify the clonality of T cells by GeneScan technique. Results: One to seven of TCR Vα subfamilies could be detected in peripheral blood T cells from 9 cases with APL, the frequent expression of Vα subfamilies predominated in Vα3and Vα19. Clonal expanded T cells could be detected in 8 APL patients, which predominant used Vα3, Vα26 or Vα27 (3 out of 8 cases). However, almost all Vα subfamilies with polyclonal expansion could be detected in peripheral blood T cells from 10 cases of normal individuals. Conclusion: Remarkable skew distribution and clonal expansion of TCR Vα subfamilies T cells is the common feature in patients with APL. Clonal expansion of T cells might reflect a response in host to APL cell associated antigen, whether these expanded T cells have the ability for specific cytotoxicity against APL cells, remains an open question.

  13. Crystal structures of two transcriptional regulators from Bacillus cereus define the conserved structural features of a PadR subfamily.

    Directory of Open Access Journals (Sweden)

    Guntur Fibriansah

    Full Text Available PadR-like transcriptional regulators form a structurally-related family of proteins that control the expression of genes associated with detoxification, virulence and multi-drug resistance in bacteria. Only a few members of this family have been studied by genetic, biochemical and biophysical methods, and their structure/function relationships are still largely undefined. Here, we report the crystal structures of two PadR-like proteins from Bacillus cereus, which we named bcPadR1 and bcPadR2 (products of gene loci BC4206 and BCE3449 in strains ATCC 14579 and ATCC 10987, respectively. BC4206, together with its neighboring gene BC4207, was previously shown to become significantly upregulated in presence of the bacteriocin AS-48. DNA mobility shift assays reveal that bcPadR1 binds to a 250 bp intergenic region containing the putative BC4206-BC4207 promoter sequence, while in-situ expression of bcPadR1 decreases bacteriocin tolerance, together suggesting a role for bcPadR1 as repressor of BC4206-BC4207 transcription. The function of bcPadR2 (48% identical in sequence to bcPadR1 is unknown, but the location of its gene just upstream from genes encoding a putative antibiotic ABC efflux pump, suggests a role in regulating antibiotic resistance. The bcPadR proteins are structurally similar to LmrR, a PadR-like transcription regulator in Lactococcus lactis that controls expression of a multidrug ABC transporter via a mechanism of multidrug binding and induction. Together these proteins define a subfamily of conserved, relatively small PadR proteins characterized by a single C-terminal helix for dimerization. Unlike LmrR, bcPadR1 and bcPadR2 lack a central pore for ligand binding, making it unclear whether the transcriptional regulatory roles of bcPadR1 and bcPadR2 involve direct ligand recognition and induction.

  14. Crystal structures of two transcriptional regulators from Bacillus cereus define the conserved structural features of a PadR subfamily.

    Science.gov (United States)

    Fibriansah, Guntur; Kovács, Ákos T; Pool, Trijntje J; Boonstra, Mirjam; Kuipers, Oscar P; Thunnissen, Andy-Mark W H

    2012-01-01

    PadR-like transcriptional regulators form a structurally-related family of proteins that control the expression of genes associated with detoxification, virulence and multi-drug resistance in bacteria. Only a few members of this family have been studied by genetic, biochemical and biophysical methods, and their structure/function relationships are still largely undefined. Here, we report the crystal structures of two PadR-like proteins from Bacillus cereus, which we named bcPadR1 and bcPadR2 (products of gene loci BC4206 and BCE3449 in strains ATCC 14579 and ATCC 10987, respectively). BC4206, together with its neighboring gene BC4207, was previously shown to become significantly upregulated in presence of the bacteriocin AS-48. DNA mobility shift assays reveal that bcPadR1 binds to a 250 bp intergenic region containing the putative BC4206-BC4207 promoter sequence, while in-situ expression of bcPadR1 decreases bacteriocin tolerance, together suggesting a role for bcPadR1 as repressor of BC4206-BC4207 transcription. The function of bcPadR2 (48% identical in sequence to bcPadR1) is unknown, but the location of its gene just upstream from genes encoding a putative antibiotic ABC efflux pump, suggests a role in regulating antibiotic resistance. The bcPadR proteins are structurally similar to LmrR, a PadR-like transcription regulator in Lactococcus lactis that controls expression of a multidrug ABC transporter via a mechanism of multidrug binding and induction. Together these proteins define a subfamily of conserved, relatively small PadR proteins characterized by a single C-terminal helix for dimerization. Unlike LmrR, bcPadR1 and bcPadR2 lack a central pore for ligand binding, making it unclear whether the transcriptional regulatory roles of bcPadR1 and bcPadR2 involve direct ligand recognition and induction.

  15. Isolation of two novel ras genes in Dictyostelium discoideum; evidence for a complex, developmentally regulated ras gene subfamily.

    Science.gov (United States)

    Daniel, J; Bush, J; Cardelli, J; Spiegelman, G B; Weeks, G

    1994-02-01

    In Dictyostelium discoideum, three ras genes (rasD, rasG and rasB) and one ras-related gene (rap1) have been previously isolated and characterized, and the deduced amino acid sequence of their predicted protein products share at least 50% sequence identity with the human H-Ras protein. We have now cloned and characterized two additional members of the ras gene subfamily in Dictyostelium, rasC and rasS. These genes are developmentally regulated and unlike the previously isolated Dictyostelium ras genes, maximum levels of their transcripts were detected during aggregation, suggesting that the encoded proteins have distinct functions during aggregation. The rasC cDNA encodes a 189 amino acid protein that is 65% identical to the Dictyostelium RasD and RasG proteins and 56% identical to the human H-Ras protein. The predicted 194 amino acid gene product encoded by rasS is 60% identical to the Dictyostelium RasD and RasG proteins and 54% identical to the human H-Ras protein. Whereas RasD, RasG, RasB and Rap1 are totally conserved in their putative effector domains relative to H-Ras, RasC and RasS have single amino acid substitutions in their effector domains, consistent with the idea that they have unique functions. In RasC, aspartic acid-38 has been replaced by asparagine (D38N), and in RasS, isoleucine-36 has been replaced by leucine (I36L). In addition, both proteins have several differences in the effector-proximal domain, a domain which is believed to play a role in Ras target activation. In RasC, there is a single conservative amino acid change in the canonical sequence of the binding site for the Ras-specific monoclonal antibody Y13-259, and consequently, RasC is less immunoreactive with the antibody than either of the Dictyostelium RasD or RasG proteins. In contrast, RasS, which has three substitutions in the Y13-259 binding site, does not react with the Y13-259 antibody.

  16. Evolution of a novel subfamily of nuclear receptors with members that each contain two DNA binding domains

    Directory of Open Access Journals (Sweden)

    Hirai Hirohisa

    2007-02-01

    Full Text Available Abstract Background Nuclear receptors (NRs are important transcriptional modulators in metazoans which regulate transcription through binding to the promoter region of their target gene by the DNA binding domain (DBD and activation or repression of mRNA synthesis through co-regulators bound to the ligand binding domain (LBD. NRs typically have a single DBD with a LBD. Results Three nuclear receptors named 2DBD-NRs, were identified from the flatworm Schistosoma mansoni that each possess a novel set of two DBDs in tandem with a LBD. They represent a novel NR modular structure: A/B-DBD-DBD-hinge-LBD. The 2DBD-NRs form a new subfamily of NRs, VII. By database mining, 2DBD-NR genes from other flatworm species (Schmidtea mediterranea and Dugesia japonica, from Mollusks (Lottia gigantean and from arthropods (Daphnia pulex were also identified. All 2DBD-NRs possess a P-box sequence of CEACKK in the first DBD, which is unique to 2DBD-NRs, and a P-box sequence of CEGCKG in the second DBD. Phylogenetic analyses of both DBD and ligand binding domain sequences showed that 2DBD-NR genes originate from a common two DBD-containing ancestor gene. A single 2DBD-NR orthologue was found in Arthropoda, Platyhelminths and Mollusca. Subsequent 2DBD-NR gene evolution in Mollusks and Platyhelminths involved gene duplication. Chromosome localization of S. mansoni 2DBD-NR genes by Fluorescent in situ hybridization (FISH suggests that 2DBD-NR genes duplicated on different chromosomes in the Platyhelminths. Dimerization of Sm2DBDα indicates that 2DBD-NRs may act as homodimers, suggesting either that two repeats of a half-site are necessary for each DBD of 2DBD-NRs to bind to its target gene, or that each 2DBD-NR can recognize multiple sites. Conclusion 2DBD-NRs share a common ancestor gene which possessed an extra DBD that likely resulted from a recombination event. After the split of the Arthropods, Mollusks and Platyhelminths, 2DBD-NR underwent a recent duplication in a

  17. Phylogenetic relationships and biogeographical patterns in Circum-Mediterranean subfamily Leuciscinae (Teleostei, Cyprinidae inferred from both mitochondrial and nuclear data

    Directory of Open Access Journals (Sweden)

    Perea Silvia

    2010-08-01

    Full Text Available Abstract Background Leuciscinae is a subfamily belonging to the Cyprinidae fish family that is widely distributed in Circum-Mediterranean region. Many efforts have been carried out to deciphering the evolutionary history of this group. Thus, different biogeographical scenarios have tried to explain the colonization of Europe and Mediterranean area by cyprinids, such as the "north dispersal" or the "Lago Mare dispersal" models. Most recently, Pleistocene glaciations influenced the distribution of leuciscins, especially in North and Central Europe. Weighing up these biogeographical scenarios, this paper constitutes not only the first attempt at deciphering the mitochondrial and nuclear relationships of Mediterranean leuciscins but also a test of biogeographical hypotheses that could have determined the current distribution of Circum-Mediterranean leuciscins. Results A total of 4439 characters (mitochondrial + nuclear from 321 individuals of 176 leuciscine species rendered a well-supported phylogeny, showing fourteen main lineages. Analyses of independent mitochondrial and nuclear markers supported the same main lineages, but basal relationships were not concordant. Moreover, some incongruence was found among independent mitochondrial and nuclear phylogenies. The monophyly of some poorly known genera such as Pseudophoxinus and Petroleuciscus was rejected. Representatives of both genera belong to different evolutionary lineages. Timing of cladogenetic events among the main leuciscine lineages was gained using mitochondrial and all genes data set. Conclusions Adaptations to a predatory lifestyle or miniaturization have superimposed the morphology of some species. These species have been separated into different genera, which are not supported by a phylogenetic framework. Such is the case of the genera Pseudophoxinus and Petroleuciscus, which real taxonomy is not well known. The diversification of leuciscine lineages has been determined by intense

  18. Identification and characterization of three TLR1 subfamily members from the orange-spotted grouper, Epinephelus coioides.

    Science.gov (United States)

    Li, Yan-Wei; Xu, Dong-Dong; Li, Xia; Mo, Ze-Quan; Luo, Xiao-Chun; Li, An-Xing; Dan, Xue-Ming

    2016-08-01

    Toll-like receptors (TLRs), which play important roles in host defense against pathogen infection, are the most intensively studied pattern recognition receptors (PRRs). In this study, we identified three novel TLR1 subfamily members, including TLR1 (EcTLR1b), TLR2 (EcTLR2b) and TLR14 (EcTLR14), from the orange-spotted grouper (Epinephelus coioides). EcTLR1b and EcTLR2b displayed low sequence identity with the previously reported grouper TLR1 (EcTLR1a) and TLR2 (EcTLR2a), respectively. The open reading frames (ORFs) of EcTLR1b, EcTLR2b and EcTLR14 contain 2484 bp, 2394 bp and 2640 bp, which encode the corresponding 827 amino acids (aa), 797 aa and 879 aa, respectively. All three TLRs have leucine-rich repeat (LRR) domains (including an LRR-NT (except for EcTLR1b), several LRR motifs and an LRR-CT), a trans-membrane region and a Toll/interleukin-1 receptor (TIR) domain. The TIR domains of the three TLRs exhibited conserved boxes, namely box1, box2 and box3, and their 3D models were similar to those of human TLR1 or TLR2. Sequence alignment demonstrated that the TIR domains of the three TLRs shared higher sequence identity with those of other species than the full-length receptors. Phylogenetic analysis indicated that EcTLR1s and EcTLR2s are characterized by their differing evolutionary status, whereas EcTLR14 was found to be in the same group as other piscine TLR14/18s. The three TLRs were ubiquitously expressed in seven tested tissues of healthy groupers, although their expression profiles were different. Post Cryptocaryon irritans infection, TLR1s expression was up-regulated in the gills. The expression of TLR2b was mainly increased in the spleen, but decreased in the gills, which was similar to the expression pattern of TLR2a post C. irritans infection. Unlike EcTLR1b and EcTLR2b, however, the grouper TLR14 transcript was substantially induced in both tissues post challenge. These findings may be helpful in understanding the innate immune mechanism of host

  19. Differential geometry

    CERN Document Server

    Graustein, William C

    2006-01-01

    This first course in differential geometry presents the fundamentals of the metric differential geometry of curves and surfaces in a Euclidean space of three dimensions. Written by an outstanding teacher and mathematician, it explains the material in the most effective way, using vector notation and technique. It also provides an introduction to the study of Riemannian geometry.Suitable for advanced undergraduates and graduate students, the text presupposes a knowledge of calculus. The first nine chapters focus on the theory, treating the basic properties of curves and surfaces, the mapping of

  20. Constraint Differentiation

    DEFF Research Database (Denmark)

    Mödersheim, Sebastian Alexander; Basin, David; Viganò, Luca

    2010-01-01

    , under the assumption that the original constraint-based approach has these properties. Practically, as a concrete case study, we have integrated this technique into OFMC, a state-of-the-art model-checker for security protocol analysis, and demonstrated its effectiveness by extensive experimentation. Our......We introduce constraint differentiation, a powerful technique for reducing search when model-checking security protocols using constraint-based methods. Constraint differentiation works by eliminating certain kinds of redundancies that arise in the search space when using constraints to represent...

  1. Differential geometry

    CERN Document Server

    Guggenheimer, Heinrich W

    1977-01-01

    This is a text of local differential geometry considered as an application of advanced calculus and linear algebra. The discussion is designed for advanced undergraduate or beginning graduate study, and presumes of readers only a fair knowledge of matrix algebra and of advanced calculus of functions of several real variables. The author, who is a Professor of Mathematics at the Polytechnic Institute of New York, begins with a discussion of plane geometry and then treats the local theory of Lie groups and transformation groups, solid differential geometry, and Riemannian geometry, leading to a

  2. First record of the subfamily Proctolabinae (Orthoptera: Acridoidea: Acrididae from Argentina Primer registro de la subfamilia Proctolabinae (Orthoptera: Acridoidea: Acrididae para la Argentina

    Directory of Open Access Journals (Sweden)

    Christian Bardi

    2010-12-01

    Full Text Available This contribution records for the first time the subfamily Proctolabinae from Argentina. This subfamily contains 29 genera and 209 species restricted to the Neotropics with only one genus, Eucephalacris Descamps, reaching south as far as Mato Grosso in Brazil and northern Paraguay. Specimens belonging to Eucephalacris borellii (Giglio-Tos were collected in Misiones province. The presence of this species registered herein raises to eleven the number of Acrididae subfamilies known to occur in the country, and highlights the importance of conducting surveys of Acridoidea and Orthoptera in general, in diverse regions of Argentina. Brief diagnoses and illustrations of the characters that allowed the identification of the genus and species are also given in this contribution.Esta contribución registra por primera vez la subfamilia Proctolabinae para la Argentina. La subfamilia Proctolabinae contiene 29 géneros y 209 especies restringidas a la región Neotropical, con sólo uno de sus géneros, Eucephalacris Descamps, que llega al sur hasta Mato Grosso en Brasil y el norte de Paraguay. Ejemplares pertenecientes a Eucephalacris borellii (Giglio-Tos fueron colectados en el departamento de Guaraní, provincia de Misiones. La presencia de Eucephalacris borellii, registrada en este trabajo, eleva a once el número de subfamilias de Acrididae presentes en la Argentina, y destaca la necesidad de realizar relevamientos sobre la diversidad de Acridoidea y de Orthoptera en general, en diversas regiones de nuestro país. También se brindan en esta contribución una breve diagnosis e ilustraciones de los caracteres que permiten la identificación del género y de la especie.

  3. Biting midges of the subfamily Forcipomyiinae (Diptera: Ceratopogonidae) from the Middle East, with keys and descriptions of new species.

    Science.gov (United States)

    Alwin-Kownacka, Alicja; Szadziewski, Ryszard; Szwedo, Jacek

    2016-10-05

    Middle East biting midges of the genera Atrichopogon Kieffer and Forcipomyia Meigen, subfamily Forcipomyiinae Lenz, covering 41 species are reviewed. Two new species are described and illustrated: Forcipomyia (F.) siverekensis Alwin & Szadziewski sp. nov. and Forcipomyia (Microhelea) borkenti Alwin & Szadziewski sp. nov. The list includes 16 species of Atrichopogon and 25 of Forcipomyia. Nine species previously described by Vimmer and Kieffer from the Middle East are treated as nomina dubia and not included in the list.        Keys to identification of Atrichopogon and Forcipomyia species of the Middle East are also provided.

  4. Differentiation of papillae and rostral sensory neurons in the larva of the ascidian Botryllus schlosseri (Tunicata).

    Science.gov (United States)

    Caicci, Federico; Zaniolo, Giovanna; Burighel, Paolo; Degasperi, Valentina; Gasparini, Fabio; Manni, Lucia

    2010-02-15

    During the metamorphosis of tunicate ascidians, the swimming larva uses its three anterior papillae to detect the substrate for settlement, reabsorbs its chordate-like tail, and becomes a sessile oozooid. In view of the crucial role played by the anterior structures and their nerve relations, we applied electron microscopy and immunocytochemistry to study the larva of the colonial ascidian Botryllus schlosseri, following differentiation of the anterior epidermis during late embryogenesis, the larval stage, and the onset of metamorphosis. Rudiments of the papillae appear in the early tail-bud stage as ectodermic protrusions, the apexes of which differentiate into central and peripheral bipolar neurons. Axons fasciculate into two nerves direct to the brain. Distally, the long, rod-like dendritic terminations extend during the larval stage, becoming exposed to sea water. After the larva selects and adheres to the substrate, these neurons retract and regress. Adjacent to the papillae, other scattered neurons insinuate dendrites into the tunic and form the net of rostral trunk epidermal neurons (RTENs) which fasciculate together with the papillary neurons. Our data indicate that the papillae are simple and coniform, the papillary neurons are mechanoreceptors, and the RTENs are chemoreceptors. The interpapillary epidermal area, by means of an apocrine secretion, provides sticky material for temporary adhesion of the larva to the substrate.

  5. Differential topology

    CERN Document Server

    Margalef-Roig, J

    1992-01-01

    ...there are reasons enough to warrant a coherent treatment of the main body of differential topology in the realm of Banach manifolds, which is at the same time correct and complete. This book fills the gap: whenever possible the manifolds treated are Banach manifolds with corners. Corners add to the complications and the authors have carefully fathomed the validity of all main results at corners. Even in finite dimensions some results at corners are more complete and better thought out here than elsewhere in the literature. The proofs are correct and with all details. I see this book as a reliable monograph of a well-defined subject; the possibility to fall back to it adds to the feeling of security when climbing in the more dangerous realms of infinite dimensional differential geometry. Peter W. Michor

  6. The distribution of glutathione and homoglutathione in leaf, root and seed tissue of 73 species across the three sub-families of the Leguminosae.

    Science.gov (United States)

    Colville, Louise; Sáez, Clara M Blanco; Lewis, Gwilym P; Kranner, Ilse

    2015-07-01

    Homoglutathione (γ-glutamyl-cysteinyl-β-alanine) is a homologue of glutathione (γ-glutamyl-cysteinyl-glycine), which is a ubiquitous and indispensable tripeptide in eukaryotes with multi-facetted functions, many of which relate to cellular redox regulation. Homoglutathione is unique to the Leguminosae family, but studies of its occurrence have been restricted to the Papilionoideae subfamily, and almost exclusively to crop species. To determine whether the distribution of homoglutathione in the Leguminosae has a phylogenetic basis the occurrence of homoglutathione was investigated in the leaves, roots and seeds of 73 wild species of Leguminosae, representing 30 tribes across the Caesalpinioideae, Mimosoideae and Papilionoideae subfamilies. Homoglutathione was found only in the Papilionoideae, and was generally restricted to the 'Old World Clade'. It is proposed that homoglutathione may have arisen following a whole genome duplication event after the divergence of the Old World Clade. Homoglutathione is believed to fulfil the same functional roles as glutathione, but this study showed that homoglutathione and glutathione have different tissue-specific distribution patterns. Homoglutathione tended to occur more frequently in root tissue, and higher concentrations were found in leaves and roots, whereas glutathione tended to be present at the highest concentrations in seeds. This may reflect a distinct role for homoglutathione, particularly in roots, or an inability of homoglutathione to functionally replace glutathione in reproductive tissues. However, no relationships with environmental factors or nodulation were observed. Greater understanding of the factors that influence homoglutathione distribution may help to elucidate its unique function in some legume species.

  7. Crystal structure and biochemical investigations reveal novel mode of substrate selectivity and illuminate substrate inhibition and allostericity in a subfamily of Xaa-Pro dipeptidases.

    Science.gov (United States)

    Are, Venkat N; Kumar, Ashwani; Kumar, Saurabh; Goyal, Venuka Durani; Ghosh, Biplab; Bhatnagar, Deepak; Jamdar, Sahayog N; Makde, Ravindra D

    2017-02-01

    Xaa-Pro dipeptidase (XPD) catalyzes hydrolysis of iminopeptide bond in dipeptides containing trans-proline as a second residue. XPDs are found in all living organisms and are believed to play an essential role in proline metabolism. Here, we report crystal structures and extensive enzymatic studies of XPD from Xanthomonas campestris (XPDxc), the first such comprehensive study of a bacterial XPD. We also report enzymatic activities of its ortholog from Mycobacterium tuberculosis (XPDmt). These enzymes are strictly dipeptidases with broad substrate specificities. They exhibit substrate inhibition and allostericity, as described earlier for XPD from Lactococcus lactis (XPDll). The structural, mutational and comparative data have revealed a novel mechanism of dipeptide selectivity and substrate binding in these enzymes. Moreover, we have identified conserved sequence motifs that distinguish these enzymes from other prolidases, thus defining a new subfamily. This study provides a suitable structural template for explaining unique properties of this XPDxc subfamily. In addition, we report unique structural features of XPDxc protein like an extended N-terminal tail region and absence of a conserved Tyr residue near the active site.

  8. A phylogenetic analysis using multidirectional chromosome painting of three species (Uroderma magnirostrum, U. bilobatum and Artibeus obscurus) of subfamily Stenodermatinae (Chiroptera-Phyllostomidae).

    Science.gov (United States)

    Pieczarka, J C; Gomes, A J B; Nagamachi, C Y; Rocha, D C C; Rissino, J D; O'Brien, P C M; Yang, F; Ferguson-Smith, M A

    2013-07-01

    The species of genera Uroderma and Artibeus are medium-sized bats belonging to the family Phyllostomidae and subfamily Stenodermatinae (Mammalia, Chiroptera) from South America. They have a wide distribution in the Neotropical region, with two currently recognized species in Uroderma and approximately 20 species in Artibeus. These two genera have different rates of chromosome evolution, with Artibeus probably having retained the ancestral karyotype for the subfamily. We used whole chromosome paint probe sets from Carollia brevicauda and Phyllostomus hastatus on Uroderma magnirostrum, Uroderma bilobatum, and Artibeus obscurus. With the aim of testing the previous phylogenies of these bats using cytogenetics, we compared these results with published painting maps on Phyllostomidae. The genome-wide comparative maps based on chromosome painting and chromosome banding reveal the chromosome forms that characterize each taxonomic level within the Phyllostomidae and show the chromosome evolution of this family. Based on this, we are able to suggest an ancestral karyotype for Phyllostomidae. Our cladistic analysis is an independent confirmation using multidirectional chromosome painting of the previous Phyllostomidae phylogenies.

  9. Key to larvae of the South American subfamilies of weevils (Coleoptera, Curculionoidea Clave para larvas de las subfamilias sudamericanas de gorgojos (Coleoptera, Curculionoidea

    Directory of Open Access Journals (Sweden)

    ADRIANA E. MARVALDI

    2003-12-01

    Full Text Available The weevils (Coleoptera: Curculionoidea from South America are classsified into seven families and 28 subfamilies as follows: Nemonychidae (Rhinorhynchinae, Anthribidae (Anthribinae, Belidae (Belinae and Oxycoryninae, Attelabidae (Attelabinae and Rhynchitinae, Brentidae (Apioninae and Brentinae, Caridae (Carinae and Curculionidae (Erirhininae, Dryophthorinae, Entiminae, Aterpinae, Gonipterinae, Rhythirrininae, Thecesterninae, Eugnominae, Hyperinae, Curculioninae, Cryptorhynchinae, Mesoptiliinae (= Magdalidinae, Molytinae, Baridinae, Lixinae, Conoderinae (= Zygopinae, Cossoninae, Scolytinae and Platypodinae. A dichotomous key for the larval stage is provided for identification of the families and subfamilies of Curculionoidea present in South America. The key is based on external morphological characters and contains data on larval feeding habitsLos gorgojos (Coleoptera: Curculionoidea de Sudamérica están clasificados en siete familias y 28 subfamilias como se muestra a continuación: Nemonychidae (Rhinorhynchinae, Anthribidae (Anthribinae, Belidae (Belinae y Oxycoryninae, Attelabidae (Attelabinae y Rhynchitinae, Brentidae (Apioninae y Brentinae, Caridae (Carinae y Curculionidae (Erirhininae, Dryophthorinae, Entiminae, Aterpinae, Gonipterinae, Rhythirrininae, Thecesterninae, Eugnominae, Hyperinae, Curculioninae, Cryptorhynchinae, Mesoptiliinae (= Magdalidinae, Molytinae, Baridinae, Lixinae, Conoderinae (= Zygopinae, Cossoninae, Scolytinae y Platypodinae. Se brinda una clave dicotómica para el estado de larva de Curculionoidea en Sudamérica, para su determinación a nivel de familias y subfamilias. La clave está basada sobre caracteres morfológicos externos y se presentan además datos de hábitos alimentarios

  10. A subfamily of putative cytokinin receptors is revealed by an analysis of the evolution of the two-component signaling system of plants.

    Science.gov (United States)

    Gruhn, Nijuscha; Halawa, Mhyeddeen; Snel, Berend; Seidl, Michael F; Heyl, Alexander

    2014-05-01

    The two-component signaling system--the major signaling pathway of bacteria--is found among higher eukaryotes only in plants, where it regulates diverse processes, such as the signaling of the phytohormone cytokinin. Cytokinin is perceived by a hybrid histidine (His) kinase receptor, and the signal is transduced by a multistep phosphorelay system of His phosphotransfer proteins and different classes of response regulators (RRs). To shed light on the origin and evolution of the two-component signaling system members in plants, we conducted a comprehensive domain-based phylogenetic study across the relevant kingdoms, including Charophyceae algae, the group of green algae giving rise to land plants. Surprisingly, we identified a subfamily of cytokinin receptors with members only from the early diverging land plants Marchantia polymorpha and Physcomitrella patens and then experimentally characterized two members of this subfamily. His phosphotransfer proteins of Charophyceae seemed to be more closely related to land plants than to other groups of green algae. Farther down the signaling pathway, the type-B RRs were found across all plant clades, but many members lack either the canonical Asp residue or the DNA binding domain. In contrast, the type-A RRs seemed to be limited to land plants. Finally, the analysis provided hints that one additional group of RRs, the type-C RRs, might be degenerated receptors and thus, of a different evolutionary origin than bona fide RRs.

  11. Distinct structural and redox properties of the heme active site in bacterial dye decolorizing peroxidase-type peroxidases from two subfamilies: resonance Raman and electrochemical study.

    Science.gov (United States)

    Sezer, Murat; Santos, Ana; Kielb, Patrycja; Pinto, Tiago; Martins, Ligia O; Todorovic, Smilja

    2013-05-07

    Spectroscopic data of dye decolorizing peroxidases (DyPs) from Bacillus subtilis (BsDyP), an A subfamily member, and Pseudomonas putida (PpDyP), a B subfamily enzyme, reveal distinct heme coordination patterns of the respective active sites. In solution, both enzymes show a heterogeneous spin population, with the six-coordinated low-spin state being the most populated in the former and the five-coordinated quantum mechanically mixed-spin state in the latter. We ascribe the poor catalytic activity of BsDyP to the presence of a catalytically incompetent six-coordinated low-spin population. The spin populations of the two DyPs are sensitively dependent on the pH, temperature, and physical, i.e., solution versus crystal versus immobilized, state of the enzymes. We observe a redox potential for the Fe(2+)/Fe(3+) couple in BsDyP (-40 mV) at pH 7.6 substantially more positive than those reported for the majority of other peroxidases, including PpDyP (-260 mV). Furthermore, we evaluate the potential of the studied enzymes for biotechnological applications on the basis of electrochemical and spectroelectrochemical data.

  12. 水蛇亚科形态学特征的支序分析%Morphological Phylogeny of the Water Snake Subfamily Homalopsinae (Serpent: Colubridae)

    Institute of Scientific and Technical Information of China (English)

    吕顺清; 庞峻锋; 杨大同

    2006-01-01

    The morphological phylogeny of the water snake subfamily Homalopsinae, containing 10 genera, of which seven are monotypic, was not reported up until now. Here fourteen morphological characters were selected for the cladistic analysis. Using software Hennig 86, two phylogenetic trees were inferred and the results showed that the subfamily Homalopsinae was divided into two groups. Compared with the molecular phylonenetic tree of Voris et al (2002), the genera Gerarda and Fordonia are sister groups in both studies; both studies also yielded the same monophyletic lineage, which contained three genera ( Cerberus + Erpeton + Homalopsis ). However, the position of the genus Cantoria is distinctly different with the study of Voris et al(2002).%水蛇亚科属于游蛇科,包含10个属.其中7个属为单型属.选取水蛇亚科14个形态学特征进行支序分析,并利用计算机软件Hennig 86对水蛇亚科中8个属之间的系统发育关系进行初步探讨,结果显示水蛇亚科分为两支:Gerarda和Fordonia两个属构成姊妹群,Cerberus、Erpeton和Homalopsis三个属也构成单系群,与Voris et al(2002)的分子系统树相同,但Cantoria属的地位则与Voris et al(2002)的明显不同.

  13. SLIDE, the Protein Interacting Domain of Imitation Switch Remodelers, Binds DDT-Domain Proteins of Different Subfamilies in Chromatin Remodeling Complexes

    Institute of Scientific and Technical Information of China (English)

    Jiaqiang Dong; Zheng Gao; Shujing Liu; Guang Li; Zhongnan Yang; Hai Huang; Lin Xu

    2013-01-01

    The Imitation Switch (ISWI) type adenosine triphosphate (ATP)-dependent chromatin remodeling factors are conserved proteins in eukaryotes, and some of them are known to form stable remodeling complexes with members from a family of proteins, termed DDT-domain proteins. Although it is well documented that ISWIs play important roles in different biological processes in many eukaryotic species, the molecular basis for protein interactions in ISWI complexes has not been fully addressed. Here, we report the identification of interaction domains for both ISWI and DDT-domain proteins. By analyzing CHROMATIN REMODELING11 (CHR11) and RINGLET1 (RLT1), an Arabidopsis thaliana ISWI (AtISWI) and AtDDT-domain protein, respectively, we show that the SLIDE domain of CHR11 and the DDT domain together with an adjacent sequence of RLT1 are responsible for their binding. The Arabidopsis genome contains at least 12 genes that encode DDT-domain proteins, which could be grouped into five subfamilies based on the sequence similarity. The SLIDE domain of AtISWI is able to bind members from different AtDDT subfamilies. Moreover, a human ISWI protein SNF2H is capable of binding AtDDT-domain proteins through its SLIDE domain, suggesting that binding to DDT-domain proteins is a conserved biochemical function for the SLIDE domain of ISWIs in eukaryotes.

  14. iDPF-PseRAAAC: A Web-Server for Identifying the Defensin Peptide Family and Subfamily Using Pseudo Reduced Amino Acid Alphabet Composition.

    Directory of Open Access Journals (Sweden)

    Yongchun Zuo

    Full Text Available Defensins as one of the most abundant classes of antimicrobial peptides are an essential part of the innate immunity that has evolved in most living organisms from lower organisms to humans. To identify specific defensins as interesting antifungal leads, in this study, we constructed a more rigorous benchmark dataset and the iDPF-PseRAAAC server was developed to predict the defensin family and subfamily. Using reduced dipeptide compositions were used, the overall accuracy of proposed method increased to 95.10% for the defensin family, and 98.39% for the vertebrate subfamily, which is higher than the accuracy from other methods. The jackknife test shows that more than 4% improvement was obtained comparing with the previous method. A free online server was further established for the convenience of most experimental scientists at http://wlxy.imu.edu.cn/college/biostation/fuwu/iDPF-PseRAAAC/index.asp. A friendly guide is provided to describe how to use the web server. We anticipate that iDPF-PseRAAAC may become a useful high-throughput tool for both basic research and drug design.

  15. Differential geometry

    CERN Document Server

    Kreyszig, Erwin

    1991-01-01

    An introductory textbook on the differential geometry of curves and surfaces in three-dimensional Euclidean space, presented in its simplest, most essential form, but with many explanatory details, figures and examples, and in a manner that conveys the theoretical and practical importance of the different concepts, methods and results involved. With problems at the end of each section, and solutions listed at the end of the book. Includes 99 illustrations.

  16. Differential equations

    CERN Document Server

    Tricomi, FG

    2013-01-01

    Based on his extensive experience as an educator, F. G. Tricomi wrote this practical and concise teaching text to offer a clear idea of the problems and methods of the theory of differential equations. The treatment is geared toward advanced undergraduates and graduate students and addresses only questions that can be resolved with rigor and simplicity.Starting with a consideration of the existence and uniqueness theorem, the text advances to the behavior of the characteristics of a first-order equation, boundary problems for second-order linear equations, asymptotic methods, and diff

  17. Differential geometry

    CERN Document Server

    Ciarlet, Philippe G

    2007-01-01

    This book gives the basic notions of differential geometry, such as the metric tensor, the Riemann curvature tensor, the fundamental forms of a surface, covariant derivatives, and the fundamental theorem of surface theory in a selfcontained and accessible manner. Although the field is often considered a classical one, it has recently been rejuvenated, thanks to the manifold applications where it plays an essential role. The book presents some important applications to shells, such as the theory of linearly and nonlinearly elastic shells, the implementation of numerical methods for shells, and

  18. The Exiguobacterium sibiricum 255-15 GtfC Enzyme Represents a Novel Glycoside Hydrolase 70 Subfamily of 4,6-α-Glucanotransferase Enzymes

    Science.gov (United States)

    Gangoiti, Joana; Pijning, Tjaard

    2015-01-01

    The glycoside hydrolase 70 (GH70) family originally was established for glucansucrase enzymes found solely in lactic acid bacteria synthesizing α-glucan polysaccharides from sucrose (e.g., GtfA). In recent years, we have characterized GtfB and related Lactobacillus enzymes as 4,6-α-glucanotransferase enzymes. These GtfB-type enzymes constitute the first GH70 subfamily of enzymes that are unable to act on sucrose as a substrate but are active with maltodextrins and starch, cleave α1→4 linkages, and synthesize linear α1→6-glucan chains. The GtfB disproportionating type of activity results in the conversion of malto-oligosaccharides into isomalto/malto-polysaccharides with a relatively high percentage of α1→6 linkages. This paper reports the identification of the members of a second GH70 subfamily (designated GtfC enzymes) and the characterization of the Exiguobacterium sibiricum 255-15 GtfC enzyme, which is also inactive with sucrose and displays 4,6-α-glucanotransferase activity with malto-oligosaccharides. GtfC differs from GtfB in synthesizing isomalto/malto-oligosaccharides. Biochemically, the GtfB- and GtfC-type enzymes are related, but phylogenetically, they clearly constitute different GH70 subfamilies, displaying only 30% sequence identity. Whereas the GtfB-type enzyme largely has the same domain order as glucansucrases (with α-amylase domains A, B, and C plus domains IV and V), this GtfC-type enzyme differs in the order of these domains and completely lacks domain V. In GtfC, the sequence of conserved regions I to IV of clan GH-H is identical to that in GH13 (I-II-III-IV) but different from that in GH70 (II-III-IV-I because of a circular permutation of the (β/α)8 barrel. The GtfC 4,6-α-glucanotransferase enzymes thus represent structurally and functionally very interesting evolutionary intermediates between α-amylase and glucansucrase enzymes. PMID:26590275

  19. Uncharacterized conserved motifs outside the HD-Zip domain in HD-Zip subfamily I transcription factors; a potential source of functional diversity

    Directory of Open Access Journals (Sweden)

    Cabello Julieta V

    2011-03-01

    Full Text Available Abstract Background Plant HD-Zip transcription factors are modular proteins in which a homeodomain is associated to a leucine zipper. Of the four subfamilies in which they are divided, the tested members from subfamily I bind in vitro the same pseudopalindromic sequence CAAT(A/TATTG and among them, several exhibit similar expression patterns. However, most experiments in which HD-Zip I proteins were over or ectopically expressed under the control of the constitutive promoter 35S CaMV resulted in transgenic plants with clearly different phenotypes. Aiming to elucidate the structural mechanisms underlying such observation and taking advantage of the increasing information in databases of sequences from diverse plant species, an in silico analysis was performed. In addition, some of the results were also experimentally supported. Results A phylogenetic tree of 178 HD-Zip I proteins together with the sequence conservation presented outside the HD-Zip domains allowed the distinction of six groups of proteins. A motif-discovery approach enabled the recognition of an activation domain in the carboxy-terminal regions (CTRs and some putative regulatory mechanisms acting in the amino-terminal regions (NTRs and CTRs involving sumoylation and phosphorylation. A yeast one-hybrid experiment demonstrated that the activation activity of ATHB1, a member of one of the groups, is located in its CTR. Chimerical constructs were performed combining the HD-Zip domain of one member with the CTR of another and transgenic plants were obtained with these constructs. The phenotype of the chimerical transgenic plants was similar to the observed in transgenic plants bearing the CTR of the donor protein, revealing the importance of this module inside the whole protein. Conclusions The bioinformatical results and the experiments conducted in yeast and transgenic plants strongly suggest that the previously poorly analyzed NTRs and CTRs of HD-Zip I proteins play an important

  20. The Exiguobacterium sibiricum 255-15 GtfC Enzyme Represents a Novel Glycoside Hydrolase 70 Subfamily of 4,6-α-Glucanotransferase Enzymes.

    Science.gov (United States)

    Gangoiti, Joana; Pijning, Tjaard; Dijkhuizen, Lubbert

    2015-11-20

    The glycoside hydrolase 70 (GH70) family originally was established for glucansucrase enzymes found solely in lactic acid bacteria synthesizing α-glucan polysaccharides from sucrose (e.g., GtfA). In recent years, we have characterized GtfB and related Lactobacillus enzymes as 4,6-α-glucanotransferase enzymes. These GtfB-type enzymes constitute the first GH70 subfamily of enzymes that are unable to act on sucrose as a substrate but are active with maltodextrins and starch, cleave α1→4 linkages, and synthesize linear α1→6-glucan chains. The GtfB disproportionating type of activity results in the conversion of malto-oligosaccharides into isomalto/malto-polysaccharides with a relatively high percentage of α1→6 linkages. This paper reports the identification of the members of a second GH70 subfamily (designated GtfC enzymes) and the characterization of the Exiguobacterium sibiricum 255-15 GtfC enzyme, which is also inactive with sucrose and displays 4,6-α-glucanotransferase activity with malto-oligosaccharides. GtfC differs from GtfB in synthesizing isomalto/malto-oligosaccharides. Biochemically, the GtfB- and GtfC-type enzymes are related, but phylogenetically, they clearly constitute different GH70 subfamilies, displaying only 30% sequence identity. Whereas the GtfB-type enzyme largely has the same domain order as glucansucrases (with α-amylase domains A, B, and C plus domains IV and V), this GtfC-type enzyme differs in the order of these domains and completely lacks domain V. In GtfC, the sequence of conserved regions I to IV of clan GH-H is identical to that in GH13 (I-II-III-IV) but different from that in GH70 (II-III-IV-I because of a circular permutation of the (β/α)8 barrel. The GtfC 4,6-α-glucanotransferase enzymes thus represent structurally and functionally very interesting evolutionary intermediates between α-amylase and glucansucrase enzymes.

  1. A new species of Glaphyropoma: the first subterranean copionodontine catfish and the first occurrence of opercular odontodes in the subfamily (Siluriformes: Trichomycteridae

    Directory of Open Access Journals (Sweden)

    Maria Elina Bichuette

    Full Text Available A new species of the rare copionodontine genus Glaphyropoma is described from subterranean waters in the Diamantina Plateau, Bahia State, central northeastern Brazil. This is the first troglomorphic species in the subfamily Copionodontinae. It is distinguished from all other copionodontines by the presence of opercular odontodes, and further distinguished from its only congener, G. rodriguesi, by the reduction of dark integumentary pigmentation. The new species shares the single synapomorphy previously proposed for Glaphyropoma, the marked narrowing of the first hypobranchial and indirect character evidence also supports its inclusion in the genus. The presence of opercular odontodes in the new species, in combination with a reviewed hypothesis of sister group relationship between Copionodontinae and Trichogeninae, indicate that the absence of opercular odontodes in previously-known copionodontines is secondary, rather than primitive.

  2. Comparative analysis of the male reproductive accessory glands of bat species from the five Brazilian subfamilies of the family Phyllostomidae (Chiroptera).

    Science.gov (United States)

    Martins, Fabiane F; Puga, Cintia C I; Beguelini, Mateus R; Morielle-Versute, Eliana; Vilamaior, Patricia S L; Taboga, Sebastião R

    2015-04-01

    This study aimed to morphologically characterize and compare the male reproductive accessory glands (RAGs) of bats belonging to the five Brazilian subfamilies of the family Phyllostomidae (Carollia perspicillata-Carollinae; Desmodus rotundus-Desmodontinae; Glossophaga soricina-Glossophaginae; Phyllostomus discolor-Phyllostominae and Platyrrhinus lineatus-Stenodermatinae). The study demonstrated that the RAGs of phyllostomid bats were comprised of a pair of extra-abdominal bulbourethral glands and an intra-abdominal complex, composed of paraurethral glands and a prostate with two (Desmodontinae and Stenodermatinae) or three (Carollinae, Glossophaginae and Phyllostominae) different regions, with the absence of the seminal vesicles; this pattern possibly evolved from a process of compaction of the prostatic regions from an ancestor with three regions.

  3. Identification of a GH110 subfamily of alpha 1,3-galactosidases: novel enzymes for removal of the alpha 3Gal xenotransplantation antigen

    DEFF Research Database (Denmark)

    Liu, Qiyong P; Yuan, Huaiping; Bennett, Eric P;

    2008-01-01

    In search of alpha-galactosidases with improved kinetic properties for removal of the immunodominant alpha1,3-linked galactose residues of blood group B antigens, we recently identified a novel prokaryotic family of alpha-galactosidases (CAZy GH110) with highly restricted substrate specificity......,3-galactosidases that act equally well on both branched blood group B and linear alpha1,3Gal structures. We determined by one-dimensional (1)H NMR spectroscopy that GH110 enzymes function with an inverting mechanism, which is in striking contrast to all other known alpha-galactosidases that use a retaining...... mechanism. The novel GH110 subfamily offers enzymes with highly improved performance in enzymatic removal of the immunodominant alpha3Gal xenotransplantation epitope....

  4. A novel toxin from the venom of the scorpion Tityus trivittatus, is the first member of a new alpha-KTX subfamily.

    Science.gov (United States)

    Abdel-Mottaleb, Yousra; Coronas, Fredy V; de Roodt, Adolfo R; Possani, Lourival D; Tytgat, Jan

    2006-01-23

    The first example of a new sub-family of toxins (alpha-KTx20.1) from the scorpion Tityus trivittatus was purified, sequenced and characterized physiologically. It has 29 amino acid residues, three disulfide bridges assumed to adopt the cysteine-stabilized alpha/beta scaffold with a pI value of 8.98. The sequence identities with all the other known alpha-KTx are less than 40%. Its effects were verified using seven different cloned K(+) channels (vertebrate Kv1.1-1.5, Shaker IR and hERG) expressed in Xenopus leavis oocytes. The toxin-induced effects show large differences among the different K(+) channels and a preference towards Kv1.3 (EC50=7.9+/-1.4 nM).

  5. Typification of taxa of subfamily Silenoideae (Caryophyllaceae Juss. from Siberia and Russian Far East based on materials kept in the Herbarium of the Komarov Botanical Institute (LE

    Directory of Open Access Journals (Sweden)

    G. A. Lazkov

    2016-06-01

    Full Text Available Data on type material of previously not typified taxa of the subfamily Silenoideae (Caryophyllaceae Juss., kept in the Herbarium of the Komarov Botanical Institute (LE are summarized in the paper. All relevant taxa including eight species (or subsequently accepted as species: Gastrolychnis violascens Tolm., Gypsophila stricta Bunge, Heterochroa petraea Bunge, Lychnis ajanensis var. villosula Trautv. [L. villosula (Trautv. Gorschk.], L. fulgens var. wilfordi Regel [L. wilfordi (Regel Maxim.], L. tristis Bunge, Melandrium olgae Maxim., Silene melandriiformis Maxim., five varieties (Melandrium affine var. Intermedium Tolm., Silene repens var. pratensis Kom., S. repens var. alpina Kom., S. repens var. angustifolia Turcz., S. repens var. latifolia Turcz., and one form (Silene repens f. densa Kom. are lectotypified.Key words: Caryophyllaceae, Silenoideae, type specimens, typification, Komarov Botanical Institute (LE, Siberia, Far East. 

  6. Getting from A to B-exploring the activation motifs of the class B adhesion G protein-coupled receptor subfamily G member 4/GPR112

    DEFF Research Database (Denmark)

    Cornelia Peeters, Miriam; Mos, Iris; Lenselink, Eelke B;

    2016-01-01

    The adhesion G protein-coupled receptors (ADGRs/class B2 G protein-coupled receptors) constitute an ancient family of G protein-coupled receptors that have recently been demonstrated to play important roles in cellular and developmental processes. Here, we describe a first insight...... into the structure-function relationship of ADGRs using the family member ADGR subfamily G member 4 (ADGRG4)/GPR112 as a model receptor. In a bioinformatics approach, we compared conserved, functional elements of the well-characterized class A and class B1 secretin-like G protein-coupled receptors with the ADGRs. We...... identified several potential equivalent motifs and subjected those to mutational analysis. The importance of the mutated residues was evaluated by examining their effect on the high constitutive activity of the N-terminally truncated ADGRG4/GPR112 in a 1-receptor-1-G protein Saccharomyces cerevisiae...

  7. Frequency analysis of TRBV subfamily sjTRECs to characterize T-cell reconstitution in acute leukemia patients after allogeneic hematopoietic stem cell transplantation

    Directory of Open Access Journals (Sweden)

    Yang Lijian

    2011-04-01

    Full Text Available Abstract Background Allogeneic hematopoietic stem cell transplantation (allo-HSCT leads to a prolonged state of immunodeficiency and requires reconstitution of normal T-cell immunity. Signal joint T-cell receptor excision DNA circles (sjTRECs are markers of developmental proximity to the thymus that have been used to evaluate thymic function related to T-cell immune reconstitution after HSCT. To assess the proliferative history in different T-cell receptor beta variable region (TRBV subfamilies of T cells after HSCT, expansion of TRBV subfamily-naive T cells was determined by analysis of a series of TRBV-BD1 sjTRECs. Methods sjTRECs levels were detected by real-time quantitative polymerase chain reaction (PCR in peripheral blood mononuclear cells (PBMCs from 43 Chinese acute leukemia patients who underwent allo-HSCT. Twenty-three TRBV-BD1 sjTRECs were amplified by semi-nested PCR. Sixteen age-matched healthy volunteers served as normal controls. Results sjTRECs levels were low or undetectable in the first 6 weeks after allo-HSCT and increased after 8 weeks post HSCT; however, sjTRECs levels at week 20 post-HSCT were still less than normal controls. Frequencies of TRBV subfamily sjTRECs in PBMCs from recipients at week 8 post-HSCT (29.17 ± 20.97% or at week 16 post-HSCT (38.33 ± 9.03% were significantly lower than those in donors (47.92 ± 13.82% or recipients at pre-HSCT (45.83 ± 14.03%. However, frequencies of TRBV subfamily sjTRECs in recipients at week 30 post-HSCT (42.71 ± 21.62% were similar to those in donors and recipients at pre-HSCT. sjTRECs levels in donors had a positive linear correlation with sjTRECs levels in recipients within 8-12 weeks post-HSCT. Patients with acute graft-versus-host disease (GVHD or chronic GVHD had profoundly reduced TRECs levels during the first year post-HSCT. Frequencies of BV22-BD1 sjTRECs and BV23-BD1 sjTRECs in patients with GVHD were significantly lower than those in recipients at pre-HSCT, and the

  8. Transient receptor potential cation channel subfamily V member 1 expressing corneal sensory neurons can be subdivided into at least three subpopulations

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    Abdulhakeem eAlamri

    2015-06-01

    Full Text Available The cornea is innervated by 3 main functional classes of sensory neurons: polymodal nociceptors, pure mechano-nociceptors and cold-sensing neurons. Here we explored transient receptor potential cation channel subfamily V member 1 (TRPV1 expression in guinea pig corneal sensory neurons, a widely used molecular marker of polymodal nociceptors. We used retrograde tracing to identify corneal afferent neurons in the trigeminal ganglion and double label in situ hybridization and/or immunohistochemistry to determine their molecular profile. In addition, we used immunohistochemistry to reveal the neurochemistry and structure of TRPV1 expressing nerve endings in the corneal epithelium. Approximately 45% of corneal afferent neurons expressed TRPV1, 28% expressed Piezo2 (a marker of putative pure mechano-nociceptors and 8% expressed the transient receptor potential cation channel subfamily M member 8 (TRPM8; a marker of cold-sensing neurons. There was no co-expression of TRPV1 and Piezo2 in corneal afferent neurons, but 6% of TRPV1 neurons co-expressed TRPM8. The TRPV1 expressing corneal afferent neurons could be divided into 3 subpopulations on the basis of calcitonin gene-related peptide (CGRP and/or or glial cell line-derived neurotrophic factor family receptor alpha3 (GFRα3 co-expression. In the corneal epithelium, the TRPV1 axons that co-expressed CGRP and GFRα3 ended as simple unbranched endings in the wing cell layer. In contrast, those that only co-expressed GFRα3 had ramifying endings that branched and terminated in the squamous cell layer, whereas those that only co-expressed CGRP had simple endings in the basal epithelium. This study shows that the majority of TRPV1 expressing corneal afferent neurons (>90% are likely to be polymodal nociceptors. Furthermore, TRPV1 expressing corneal afferent neurons can be subdivided into specific subpopulations based on their molecular phenotype, nerve terminal morphology and distribution in the corneal

  9. Homology of the internal sac components in the leaf beetle subfamily Criocerinae and evolutionary novelties related to the extremely elongated flagellum.

    Science.gov (United States)

    Matsumura, Yoko; Yoshizawa, Kazunori

    2012-05-01

    Extremely elongated intromittent organs are found in a wide range of taxa, especially among insects. This phenomenon is generally thought to result from sexual selection, but it is predicted that limited storage space in the body cavity and the difficulty of using the elongated organs should have constrained the evolution of extreme elongation, neutralizing any selective advantage. Therefore, in groups with long intromittent organs, features that overcome these constraints may have evolved or coevolved together with intromittent organ elongation. Using a comparative morphological approach and outgroup comparisons, we identified potential constraints and key novelties that may neutralize such constraints in the leaf beetle subfamily Criocerinae. Observations of the internal sac structure throughout Criocerinae were performed. Comparing the results with preceding studies from outgroups, a ground plan of the criocerine internal sac was constructed. Our analysis also identified specific features that are always correlated with extreme elongation: the rotation of whole internal-sac sclerites and the possession of a pocket in which to store the elongated flagellum. The pocket is thought to be formed by the rotation of the sclerites, markedly altering internal sac shape from the criocerine ground plan. Onlythe clades that have acquired this derived state contain species with an elongated flagellum that distinctly exceeds the median lobe length. It is presumed that these character correlations evolved independently three times. The detected character correlations corroborate the hypothesis that there are latent adaptive constraints for the evolution of extremely elongated intromittent organs. The constraints may have been neutralized by the alteration from the criocerine ground plan resulting in the formation of a storage pocket. In conclusion, deviation from the criocerine ground plan is considered to be the evolutionary innovation that neutralized the latent adaptive

  10. Have giant lobelias evolved several times independently? Life form shifts and historical biogeography of the cosmopolitan and highly diverse subfamily Lobelioideae (Campanulaceae

    Directory of Open Access Journals (Sweden)

    Antonelli Alexandre

    2009-01-01

    Full Text Available Abstract Background The tendency of animals and plants to independently develop similar features under similar evolutionary pressures - convergence - is a widespread phenomenon in nature. In plants, convergence has been suggested to explain the striking similarity in life form between the giant lobelioids (Campanulaceae, the bellflower family of Africa and the Hawaiian Islands. Under this assumption these plants would have developed the giant habit from herbaceous ancestors independently, in much the same way as has been suggested for the giant senecios of Africa and the silversword alliance of Hawaii. Results Phylogenetic analyses based on plastid (rbcL, trnL-F and nuclear (internal transcribed spacer [ITS] DNA sequences for 101 species in subfamily Lobelioideae demonstrate that the large lobelioids from eastern Africa the Hawaiian Islands, and also South America, French Polynesia and southeast Asia, form a strongly supported monophyletic group. Ancestral state reconstructions of life form and distribution, taking into account phylogenetic uncertainty, indicate their descent from a woody ancestor that was probably confined to Africa. Molecular dating analyses using Penalized Likelihood and Bayesian relaxed clock approaches, and combining multiple calibration points, estimate their first diversification at ~25-33 million years ago (Ma, shortly followed by several long-distance dispersal events that resulted in the current pantropical distribution. Conclusion These results confidently show that lobelioid species, commonly called 'giant', are very closely related and have not developed their giant form from herbaceous ancestors independently. This study, which includes the hitherto largest taxon sampling for subfamily Lobelioideae, highlights the need for a broad phylogenetic framework for testing assumptions about morphological development in general, and convergent evolution in particular.

  11. Identification and initial characterization of the 3' end of gene transcripts encoding putative members of the pheromone receptor subfamily in Lepidoptera

    Institute of Scientific and Technical Information of China (English)

    Stephen F. Garczynski; Kevin W. Wanner; Thomas R. Unruh

    2012-01-01

    Semiochemicals,including pheromones and kairomones,used in pest management programs reduce the need for chemical insecticides,and understanding their interactions with their membrane receptors may help make them more effective in the field.Identification of odorant receptors in the Lepidoptera has mainly been achieved using bioinformatics to search DNA sequences generated by genome or expressed sequence tag (EST) sequencing projects.This study reports a rapid method to identify members of the pheromone receptor subfamily in Lepidoptera.Degenerate oligonucleotide primers were designed against a conserved amino acid sequence in the carboxyl terminus of known lepidopteran pheromone receptors,and the primers were used in a 3' rapid amplification of complementary DNA (cDNA) ends procedure.Polymerase chain reaction products generated from seven different lepidopteran species were TA cloned and sequenced.The eDNA sequences of 25 transcripts were determined to encode potential members of the pheromone receptor subfamily.These cDNAs ranged from 238 to 642 bp and encoded 49-54 amino acids of the carboxyl terminus.Analysis of the 3' untranslated region reveals that most of the transcripts contain multiple polyadenylation signal sequences,and in the case ofManduca sexta,an alternate polyadenylation signal appears to be used in transcript processing.The 3' untranslated region was also useful in determining unique receptors encoded by transcripts having highly similar nucleotide and amino acid sequences.Overall,this technique provides a complementary method of pheromone receptor identification in EST sequencing projects,or can be used as a stand-alone method in conjunction with 5' rapid amplification of cDNA ends procedures.

  12. The Atypical Response Regulator Protein ChxR Has Structural Characteristics and Dimer Interface Interactions That Are Unique within the OmpR/PhoB Subfamily

    Energy Technology Data Exchange (ETDEWEB)

    Hickey, John M.; Lovell, Scott; Battaile, Kevin P.; Hu, Lei; Middaugh, C. Russell; Hefty, P. Scott (Kansas); (HWMRI)

    2013-05-29

    Typically as a result of phosphorylation, OmpR/PhoB response regulators form homodimers through a receiver domain as an integral step in transcriptional activation. Phosphorylation stabilizes the ionic and hydrophobic interactions between monomers. Recent studies have shown that some response regulators retain functional activity in the absence of phosphorylation and are termed atypical response regulators. The two currently available receiver domain structures of atypical response regulators are very similar to their phospho-accepting homologs, and their propensity to form homodimers is generally retained. An atypical response regulator, ChxR, from Chlamydia trachomatis, was previously reported to form homodimers; however, the residues critical to this interaction have not been elucidated. We hypothesize that the intra- and intermolecular interactions involved in forming a transcriptionally competent ChxR are distinct from the canonical phosphorylation (activation) paradigm in the OmpR/PhoB response regulator subfamily. To test this hypothesis, structural and functional studies were performed on the receiver domain of ChxR. Two crystal structures of the receiver domain were solved with the recently developed method using triiodo compound I3C. These structures revealed many characteristics unique to OmpR/PhoB subfamily members: typical or atypical. Included was the absence of two {alpha}-helices present in all other OmpR/PhoB response regulators. Functional studies on various dimer interface residues demonstrated that ChxR forms relatively stable homodimers through hydrophobic interactions, and disruption of these can be accomplished with the introduction of a charged residue within the dimer interface. A gel shift study with monomeric ChxR supports that dimerization through the receiver domain is critical for interaction with DNA.

  13. Differential expression and co-regulation of carrot AOX genes (Daucus carota).

    Science.gov (United States)

    Campos, Maria Doroteia; Cardoso, Hélia Guerra; Linke, Bettina; Costa, José Hélio; de Melo, Dirce Fernandes; Justo, Lígia; Frederico, António Miguel; Arnholdt-Schmitt, Birgit

    2009-12-01

    Alternative oxidase (AOX) is a mitochondrial protein encoded by the nuclear genome. In higher plants AOX genes form a small multigene family mostly consisting of the two subfamilies AOX1 and AOX2. Daucus carota L. is characterized by a unique extension pattern of AOX genes. Different from other plant species studied so far it contains two genes in both subfamilies. Therefore, carrot was recently highlighted as an important model in AOX stress research to understand the evolutionary importance of both AOX subfamilies. Here we report on the expression patterns of DcAOX1a, DcAOX1b and DcAOX2a and DcAOX2b. Our results demonstrate that all of the four carrot AOX genes are expressed. Differential expression was observed in organs, tissues and during de novo induction of secondary root phloem explants to growth and development. DcAOX1a and DcAOX2a indicated a differential transcript accumulation but a similar co-expression pattern. The genes of each carrot AOX sub-family revealed a differential regulation and responsiveness. DcAOX2a indicated high inducibility in contrast to DcAOX2b, which generally revealed low transcript abundance and rather weak responses. In search for within-gene sequence differences between both genes as a potential reason for the differential expression patterns, the structural organization of the two genes was compared. DcAOX2a and DcAOX2b showed high sequence similarity in their open reading frames (ORFs). However, length variability was observed in the N-terminal exon1 region. The predicted cleavage site of the mitochondrial targeting sequence in this locus is untypical small for both genes and consists of 35 amino acids for DcAOX2a and of 21 amino acids for DcAOX2b. The importance of structural gene organization and the relevancy of within-gene sequence variations are discussed. Our results strengthen the value of carrot as a model plant for future studies on the importance of AOX sub family evolution.

  14. Adaptation dynamics in densely clustered chemoreceptors.

    Directory of Open Access Journals (Sweden)

    William Pontius

    Full Text Available In many sensory systems, transmembrane receptors are spatially organized in large clusters. Such arrangement may facilitate signal amplification and the integration of multiple stimuli. However, this organization likely also affects the kinetics of signaling since the cytoplasmic enzymes that modulate the activity of the receptors must localize to the cluster prior to receptor modification. Here we examine how these spatial considerations shape signaling dynamics at rest and in response to stimuli. As a model system, we use the chemotaxis pathway of Escherichia coli, a canonical system for the study of how organisms sense, respond, and adapt to environmental stimuli. In bacterial chemotaxis, adaptation is mediated by two enzymes that localize to the clustered receptors and modulate their activity through methylation-demethylation. Using a novel stochastic simulation, we show that distributive receptor methylation is necessary for successful adaptation to stimulus and also leads to large fluctuations in receptor activity in the steady state. These fluctuations arise from noise in the number of localized enzymes combined with saturated modification kinetics between the localized enzymes and the receptor substrate. An analytical model explains how saturated enzyme kinetics and large fluctuations can coexist with an adapted state robust to variation in the expression levels of the pathway constituents, a key requirement to ensure the functionality of individual cells within a population. This contrasts with the well-mixed covalent modification system studied by Goldbeter and Koshland in which mean activity becomes ultrasensitive to protein abundances when the enzymes operate at saturation. Large fluctuations in receptor activity have been quantified experimentally and may benefit the cell by enhancing its ability to explore empty environments and track shallow nutrient gradients. Here we clarify the mechanistic relationship of these large fluctuations to well-studied aspects of the chemotaxis system, precise adaptation and functional robustness.

  15. Leaf and stem CO/sub 2/ uptake in the three subfamilies of the Cactaceae. [Pereskia aculeata; Pereskia grandifolia; Maihuenia poeppigii; Carnegiea gigantea; Ferocactus acanthodes; Coryphantha vivipara; Mammillaria dioica; Opuntia ficus-inidica; Pereskiopsis porteri; Quiabentia chacoensis; Austrocylindropuntia subulata

    Energy Technology Data Exchange (ETDEWEB)

    Nobel, P.S.; Hartsock, T.L.

    1986-04-01

    Net CO/sub 2/ uptake over 24-hour periods was examined for the leaves and for the stems of 11 species of cacti representing all three subfamilies. For Pereskia aculeata, Pereskia grandifolia, and Maihuenia poeppigii (subfamily Pereskioideae), all the net shoot CO/sub 2/ uptake was by the leaves and during the daytime. In contrast, for the leafless species Carnegiea gigantea, Ferocactus acanthodes, Coryphantha vivipara, and Mammillaria dioica (subfamily Cactoideae), all the shoot net CO/sub 2/ uptake was by the stems and at night. Similarly, for leafless Opuntia ficus-indica (subfamily Opuntioideae), all net CO/sub 2/ uptake occurred at night. For leafy members of the Opuntioideae (Pereskiopsis porteri, Quiabentia chacoensis, Austrocylindropuntia subulata), at least 88% of the shoot CO/sub 2/ uptake over 24 hours was by the leaves and some CO/sub 2/ uptake occurred at night. Leaves responded to the instantaneous level of photosynthetically active radiation (PAR) during the daytime, as occurs for C/sub 3/ plants, whereas nocturnal CO/sub 2/ uptake by stems of O. ficus-indica and F. acanthodes responded to the total daily PAR, as occurs for Crassulacean acid metabolism (CAM) plants. Thus, under the well-watered conditions employed, the Pereskioideae behaved as C/sub 3/ plants, the Cactoideae behaved as CAM plants, and the Opuntioideae exhibited characteristics of both pathways.

  16. A novel cluster of mariner-like elements belonging to mellifera subfamily from spiders and insects: implications of recent horizontal transfer on the South-West Islands of Japan.

    Science.gov (United States)

    Yamada, Kaori; Kawanishi, Yuichi; Yamada, Akinori; Tokuda, Gaku; Gurung, Raj Deep; Sasaki, Takeshi; Nakajima, Yumiko; Maekawa, Hideaki

    2014-04-01

    Mariner-like elements (MLEs) have been isolated from various eukaryotic genomes and they are divided into 15 subfamilies, including main five subfamilies: mauritiana, cecropia, mellifera/capitata, irritans, and elegans/briggsae. In the present study, MLEs belonging to mellifera subfamily were isolated from various spiders and insects (Hymenoptera and Lepidoptera) inhabiting the South-West Islands of Japan and neighboring regions. MLEs isolated from 15 different species formed a distinct novel cluster in mellifera subfamily. MLEs obtained from three different species [i.e., the bee Amegilla senahai subflavescens (Amsmar1), the wasp Campsomeris sp. (Casmar1), and the swallowtail butterfly Pachliopta aristolochiae (Paamar1)] contained an intact open reading frame that encoded a putative transposase. These transposases exhibited high similarity of 97.9% among themselves. In case of Casmar1, the presence of an intact ORF was found in high frequencies (i.e., 11 out of 12 clones). In addition, these transposases also showed the presence of a terminal inverted repeat-binding motif, DD(34)D and two highly conserved amino acid motifs, (W/L)(I/L)PHQL and YSP(D/N)L(A/S)P. These two motifs differed from previously known motifs, WVPHEL and YSPDLAP. MLEs isolated from these three different species may have been inserted into their genomes by horizontal transfer. Furthermore, the presence of an intact ORF suggests that they are still active in habitats along these isolated islands.

  17. On differential characteristic classes

    OpenAIRE

    Ho, Man-Ho

    2013-01-01

    In this paper we give explicit formulas of differential characteristic classes of principal $G$-bundles with connections and prove their expected properties. In particular, we obtain explicit formulas for differential Chern classes, differential Pontryagin classes and differential Euler class. Furthermore, we show that the differential Chern class is the unique natural transformation from (Simons-Sullivan) differential $K$-theory to (Cheeger-Simons) differential characters that is compatible ...

  18. Chilean Pitavia more closely related to Oceania and Old World Rutaceae than to Neotropical groups: evidence from two cpDNA non-coding regions, with a new subfamilial classification of the family.

    Science.gov (United States)

    Groppo, Milton; Kallunki, Jacquelyn A; Pirani, José Rubens; Antonelli, Alexandre

    2012-01-01

    The position of the plant genus Pitavia within an infrafamilial phylogeny of Rutaceae (rue, or orange family) was investigated with the use of two non-coding regions from cpDNA, the trnL-trnF region and the rps16 intron. The only species of the genus, Pitavia punctata Molina, is restricted to the temperate forests of the Coastal Cordillera of Central-Southern Chile and threatened by loss of habitat. The genus traditionally has been treated as part of tribe Zanthoxyleae (subfamily Rutoideae) where it constitutes the monogeneric tribe Pitaviinae. This tribe and genus are characterized by fruits of 1 to 4 fleshy drupelets, unlike the dehiscent fruits typical of the subfamily. Fifty-five taxa of Rutaceae, representing 53 genera (nearly one-third of those in the family) and all subfamilies, tribes, and almost all subtribes of the family were included. Parsimony and Bayesian inference were used to infer the phylogeny; six taxa of Meliaceae, Sapindaceae, and Simaroubaceae, all members of Sapindales, were also used as out-groups. Results from both analyses were congruent and showed Pitavia as sister to Flindersia and Lunasia, both genera with species scattered through Australia, Philippines, Moluccas, New Guinea and the Malayan region, and phylogenetically far from other Neotropical Rutaceae, such as the Galipeinae (Galipeeae, Rutoideae) and Pteleinae (Toddalieae, former Toddalioideae). Additionally, a new circumscription of the subfamilies of Rutaceae is presented and discussed. Only two subfamilies (both monophyletic) are recognized: Cneoroideae (including Dictyolomatoideae, Spathelioideae, Cneoraceae, and Ptaeroxylaceae) and Rutoideae (including not only traditional Rutoideae but also Aurantioideae, Flindersioideae, and Toddalioideae). As a consequence, Aurantioideae (Citrus and allies) is reduced to tribal rank as Aurantieae.

  19. Chilean Pitavia more closely related to Oceania and Old World Rutaceae than to Neotropical groups: evidence from two cpDNA non-coding regions, with a new subfamilial classification of the family

    Directory of Open Access Journals (Sweden)

    Milton Groppo

    2012-12-01

    Full Text Available The position of the plant genus Pitavia within an infrafamilial phylogeny of Rutaceae (rue, or orange family was investigated with the use of two non-coding regions from cpDNA, the trnL-trnF region and the rps16 intron. The only species of the genus, Pitavia punctata Molina, is restricted to the temperate forests of the Coastal Cordillera of Central-Southern Chile and threatened by loss of habitat. The genus traditionally has been treated as part of tribe Zanthoxyleae (subfamily Rutoideae where it constitutes the monogeneric tribe Pitaviinae. This tribe and genus are characterized by fruits of 1 to 4 fleshy drupelets, unlike the dehiscent fruits typical of the subfamily. Fifty-five taxa of Rutaceae, representing 53 genera (nearly one-third of those in the family and all subfamilies, tribes, and almost all subtribes of the family were included. Parsimony and Bayesian inference were used to infer the phylogeny; six taxa of Meliaceae, Sapindaceae, and Simaroubaceae, all members of Sapindales, were also used as out-groups. Results from both analyses were congruent and showed Pitavia as sister to Flindersia and Lunasia, both genera with species scattered through Australia, Philippines, Moluccas, New Guinea and the Malayan region, and phylogenetically far from other Neotropical Rutaceae, such as the Galipeinae (Galipeeae, Rutoideae and Pteleinae (Toddalieae, former Toddalioideae. Additionally, a new circumscription of the subfamilies of Rutaceae is presented and discussed. Only two subfamilies (both monophyletic are recognized: Cneoroideae (including Dictyolomatoideae, Spathelioideae, Cneoraceae, and Ptaeroxylaceae and Rutoideae (including not only traditional Rutoideae but also Aurantioideae, Flindersioideae, and Toddalioideae. As a consequence, Aurantioideae (Citrus and allies is reduced to tribal rank as Aurantieae.

  20. Physical mapping of 18S and 5S rDNA loci and histone H3 gene in grasshopper species of the subfamily Gomphocerinae (Acrididae).

    Science.gov (United States)

    Silva-Neto, L C; Bernardino, A C S; Loreto, V; Moura, R C

    2015-11-25

    In this study, fluorescence in situ hybridization (FISH) analysis was used to determine and compare the numbers and chromosomal locations of two multigene families (rDNA and histone H3) in four Neotropical species of gomphocerine grasshoppers. FISH using the 18S rDNA probe identified a single site on the S9 chromosome of Amblytropidia sp and Cauratettix borelli, a single site on chromosome M6 of Compsacris pulcher, and two sites (chromosomes L1 and L2) in Orphulella punctata. By contrast, FISH with a 5S rDNA probe identified dispersion of this sequence in the genomes of the four species, with evidence of intraspecific variations. Amblytropidia sp had six to eight FISH signals on autosomal chromosomes, while C. pulcher exhibited a signal only on the M5 bivalent. The histone H3 gene was less variable and was restricted to a single pair in all species. The conservation of the numbers and locations of 18S rDNA and H3 genes in conjunction with data from the literature was useful for evaluating karyotype evolution in this subfamily. The variation in the number and sizes of 5S rDNA sites indicates a process of recent dispersion that might have been mediated by transposition.

  1. A systematic review of the subfamily Syringophilinae (Acari: Syringophilidae) of the Nearctic region. Part 1: quill mites associated with passerines (Aves: Passeriformes).

    Science.gov (United States)

    Skoracki, Maciej; Spicer, Greg S; Oconnor, Barry M

    2016-02-29

    Quill mites belonging to the subfamily Syringophilinae Lavoipierre, 1953 associated with the Nearctic passeriform birds are revised. All of the 49 known species, which are grouped in seven genera, are recorded. Among them, four new species are described: Syringophiloidus audubioni sp. nov. from Spizella breweri (Cassini) (Emberizidae), Syringophilopsis catesbyi sp. nov. from Vireo olivaceus (Linnaeus) (Vireonidae), S. wilsoni sp. nov. from Pheucticus melanocephalus (Swainson) (Cardinalidae), and S. bartrami sp. nov. from Spizella passerina (Bechstein) (Emberizidae). The species Syringophilopsis hylocichlae Clark, 1964 syn. nov. is synonymized with Syringophilopsis turdus (Fritsch, 1958), and Syringophiloidus zonotrichia syn. nov. is synonymized with Betasyringophiloidus seiuri (Clark, 1964) comb. nov. Six species are recorded from the Nearctic region for the first time: Syringophiloidus delichonum Bochkov, 2001, S. glandarii (Fritsch, 1958), S. weiszii Skoracki et al., 2001, S. bombycillae Skoracki, 2002, Syringophilopsis mimidus Sikora et al., 2011, and Torotrogla merulae Skoracki et al., 2000. Data on Nearctic syringophiline species, their hosts and distribution are summarized and the keys to all species are constructed.

  2. A novel DNMT3B subfamily, DeltaDNMT3B, is the predominant form of DNMT3B in non-small cell lung cancer.

    Science.gov (United States)

    Wang, Luo; Wang, Jie; Sun, Shiyong; Rodriguez, Marivonne; Yue, Ping; Jang, Se Jin; Mao, Li

    2006-07-01

    De novo promoter DNA methylation represses gene transcription and is a common mechanism to inactivate tumor suppressor genes in tumorigenesis. DNMT3B plays an important role in de novo DNA methylation. We report here the identification of a novel DNMT3B subfamily, termed DeltaDNMT3B, whose expression is initiated through a promoter located at intron 4 and exon 5 of the DNMT3B gene. At least 7 transcriptional variants of DeltaDNMT3B have been observed as the result of alternative pre-mRNA splicing. Predicted proteins derived from these variants suggest that 4 of the variants share a conservative enzymatic domain but contain a variable PWWP motif, a putative DNA binding structure, whereas 3 of the variants lack the enzymatic domain due to predicted premature translational termination. In non-small cell lung cancer (NSCLC) cell lines, DeltaDNMT3B variants are frequently expressed and are the predominant forms of DNMT3B. Similarly, DeltaDNMT3B variants are frequently expressed in primary NSCLC but are not detectable or are expressed at low levels in corresponding normal lung tissue. Our results indicate that DeltaDNMT3B is the major expression form of DNMT3B in NSCLC and may play an important role in the development of aberrant promoter methylation during lung tumorigenesis.

  3. Preferential and rapid degradation of raw rice starch by an α-amylase of glycoside hydrolase subfamily GH13_37.

    Science.gov (United States)

    Lei, Yin; Peng, Hui; Wang, Ying; Liu, Yuantao; Han, Fang; Xiao, Yazhong; Gao, Yi

    2012-06-01

    The α-amylase (AmyP) from a marine metagenomic library belongs to the recently classified glycoside hydrolase subfamily GH13_37. The degradation abilities of AmyP on a broad range of raw starch granules were examined at 40 °C and pH 7.5. It was found that AmyP is a raw starch-degrading enzyme, exhibiting a unique and remarkable ability to preferentially and very rapidly digest raw rice starch. The specific activity of raw rice starch was reached 118.5 ± 0.6 Umg(-1), which was much higher than that of other raw starches. The final hydrolysis degrees were obtained in 4 h for 1 % raw rice starch and 1 h for 8 % concentration, indicating a very rapid speed of hydrolysis. The presence of a starch residue resistant was the main limiting factor for complete hydrolysis, although end product inhibition also existed, especially at high starch concentrations. AmyP randomly attacks unique or susceptible sites on raw rice starch granules, and releases glucose, maltose, and maltotriose as end products. This is the first biochemical characterization of the raw starch-degrading ability of an α-amylase of family GH13_37. The specific ability towards raw rice starch has never been described before, and this makes AmyP a promising candidate for use as a novel enzyme in rice starch processing.

  4. Inherited surfactant deficiency due to uniparental disomy of rare mutations in the surfactant protein-B and ATP binding cassette, subfamily A, member 3 genes

    Science.gov (United States)

    Hamvas, Aaron; Nogee, Lawrence M.; Wegner, Daniel J.; DePass, Kelcey; Christodoulou, John; Bennetts, Bruce; McQuade, Leon R.; Gray, Peter H.; Deterding, Robin R.; Carroll, Travis R.; Kammesheidt, Anja; Kasch, Laura M.; Kulkarni, Shashikant; Cole, F. Sessions

    2009-01-01

    Objective To characterize inheritance of homozygous, rare, recessive loss-of-function mutations in the surfactant protein-B (SFTPB) or ATP binding cassette, subfamily A, member 3 (ABCA3) genes in newborns with lethal respiratory failure. Study design We resequenced parents whose infants were homozygous for mutations in SFTPB or ABCA3. For infants with only one heterozygous parent, we performed microsatellite analysis for chromosomes 2 (SFTPB) and 16 (ABCA3). Results We identified one infant homozygous for the c.1549C>GAA mutation (121ins2) in SFTPB for whom only the mother was heterozygous and 3 infants homozygous for mutations in ABCA3 (p.K914R, p.P147L, and c.806_7insGCT) for whom only the fathers were heterozygous. For the SP-B deficient infant, microsatellite markers confirmed maternal heterodisomy with segmental isodisomy. Microsatellite analysis confirmed paternal isodisomy for the three ABCA3 deficient infants. Two ABCA3 deficient infants underwent lung transplantation at 3 and 5 months of age, respectively, and two infants died. None exhibited any non-pulmonary phenotype. Conclusions Uniparental disomy should be suspected in infants with rare homozygous mutations in SFTPB or ABCA3. Confirmation of parental carrier status is important to provide recurrence risk and to monitor expression of other phenotypes that may emerge through reduction to homozygosity of recessive alleles. PMID:19647838

  5. Giant panda (Ailuropoda melanoleuca) population dynamics and bamboo (subfamily Bambusoideae) life history: a structured population approach to examining carrying capacity when the prey are semelparous

    Science.gov (United States)

    Carter, J.; Ackleh, A.S.; Leonard, B.P.; Wang, Hongfang

    1999-01-01

    The giant panda, Ailuropoda melanoleuca, is a highly specialized Ursid whose diet consists almost entirely of various species of bamboo. Bamboo (Bambusoideae) is a grass subfamily whose species often exhibit a synchronous semelparity. Synchronous semelparity can create local drops in carrying capacity for the panda. We modeled the interaction of pandas and their bamboo food resources with an age structured panda population model linked to a natural history model of bamboo biomass dynamics based on literature values of bamboo biomass, and giant panda life history dynamics. This paper reports the results of our examination of the interaction between pandas and their bamboo food resource and its implications for panda conservation. In the model all panda populations were well below the carrying capacity of the habitat. The giant panda populations growth was most sensitive to changes in birth rates and removal of reproductive aged individuals. Periodic starvation that has been documented in conjunction with bamboo die-offs is probably related to the inability to move to other areas within the region where bamboo is still available. Based on the results of this model, giant panda conservation should concentrate on keeping breeding individuals in the wild, keep corridors to different bamboo species open to pandas, and to concentrate research on bamboo life history.

  6. Cloning and characterization of PAK5, a novel member of mammalian p21-activated kinase-II subfamily that is predominantly expressed in brain

    DEFF Research Database (Denmark)

    Pandey, A.; Dan, I.; Kristiansen, T.Z.;

    2002-01-01

    activates the JNK kinase pathway but not p38 or ERK pathways. PAK5 transcript is predominantly expressed in brain as revealed by Northern blot and in situ hybridization. The expression pattern of PAK5 is distinct from that of PAK4 and PAK6, suggesting a functional division among PAK-II subfamily kinases......The p21-activated kinase (PAK) family of protein kinases has recently attracted considerable attention as an effector of Rho family of small G proteins and as an upstream regulator of MAPK signalling pathways during cellular events such as re-arrangement of the cytoskeleton and apoptosis. We have...... that PAK5 preferentially binds to CDC42 in the presence of GTP and that CRIB motif is essential for this interaction. PAK5 is a functional protein kinase but unlike PAK-I family kinases (PAK1, 2, and 3), the kinase activity of PAK5 does not seem to require the binding of CDC42. Overexpression of PAK5...

  7. Homodimerization Controls the Fibroblast Growth Factor 9 Subfamily's Receptor Binding and Heparan Sulfate-Dependent Diffusion in the Extracellular Matrix

    Energy Technology Data Exchange (ETDEWEB)

    Kalinina, J.; Byron, S; Makarenkova, H; Olsen, S; Eliseenkova, A; Larochelle, W; Dhanabal, M; Blais, S; Mohammadi, M; et. al.

    2009-01-01

    Uncontrolled fibroblast growth factor (FGF) signaling can lead to human diseases, necessitating multiple layers of self-regulatory control mechanisms to keep its activity in check. Herein, we demonstrate that FGF9 and FGF20 ligands undergo a reversible homodimerization, occluding their key receptor binding sites. To test the role of dimerization in ligand autoinhibition, we introduced structure-based mutations into the dimer interfaces of FGF9 and FGF20. The mutations weakened the ability of the ligands to dimerize, effectively increasing the concentrations of monomeric ligands capable of binding and activating their cognate FGF receptor in vitro and in living cells. Interestingly, the monomeric ligands exhibit reduced heparin binding, resulting in their increased radii of heparan sulfate-dependent diffusion and biologic action, as evidenced by the wider dilation area of ex vivo lung cultures in response to implanted mutant FGF9-loaded beads. Hence, our data demonstrate that homodimerization autoregulates FGF9 and FGF20's receptor binding and concentration gradients in the extracellular matrix. Our study is the first to implicate ligand dimerization as an autoregulatory mechanism for growth factor bioactivity and sets the stage for engineering modified FGF9 subfamily ligands, with desired activity for use in both basic and translational research.

  8. The mammalian Rab family of small GTPases: definition of family and subfamily sequence motifs suggests a mechanism for functional specificity in the Ras superfamily.

    Science.gov (United States)

    Pereira-Leal, J B; Seabra, M C

    2000-08-25

    The Rab/Ypt/Sec4 family forms the largest branch of the Ras superfamily of GTPases, acting as essential regulators of vesicular transport pathways. We used the large amount of information in the databases to analyse the mammalian Rab family. We defined Rab-conserved sequences that we designate Rab family (RabF) motifs using the conserved PM and G motifs as "landmarks". The Rab-specific regions were used to identify new Rab proteins in the databases and suggest rules for nomenclature. Surprisingly, we find that RabF regions cluster in and around switch I and switch II regions, i.e. the regions that change conformation upon GDP or GTP binding. This finding suggests that specificity of Rab-effector interaction cannot be conferred solely through the switch regions as is usually inferred. Instead, we propose a model whereby an effector binds to RabF (switch) regions to discriminate between nucleotide-bound states and simultaneously to other regions that confer specificity to the interaction, possibly Rab subfamily (RabSF) specific regions that we also define here. We discuss structural and functional data that support this model and its general applicability to the Ras superfamily of proteins.

  9. Role of NH{sub 2}-terminal hydrophobic motif in the subcellular localization of ATP-binding cassette protein subfamily D: Common features in eukaryotic organisms

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Asaka; Asahina, Kota; Okamoto, Takumi; Kawaguchi, Kosuke [Department of Biological Chemistry, Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama, 2630 Sugitani, Toyama 930-0194 (Japan); Kostsin, Dzmitry G. [Department of Biological Chemistry, Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama, 2630 Sugitani, Toyama 930-0194 (Japan); Institute of Biophysics and Cell Engineering, National Academy of Sciences of Belarus, Academicheskaya Str. 27, Minsk 220072 (Belarus); Kashiwayama, Yoshinori [Department of Biological Chemistry, Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama, 2630 Sugitani, Toyama 930-0194 (Japan); Takanashi, Kojiro; Yazaki, Kazufumi [Laboratory of Plant Gene Expression, Research Institute for Sustainable Humanosphere, Kyoko University, Uji, Kyoto 611-0011 (Japan); Imanaka, Tsuneo, E-mail: imanaka@pha.u-toyama.ac.jp [Department of Biological Chemistry, Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama, 2630 Sugitani, Toyama 930-0194 (Japan); Morita, Masashi [Department of Biological Chemistry, Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama, 2630 Sugitani, Toyama 930-0194 (Japan)

    2014-10-24

    Highlights: • ABCD proteins classifies based on with or without NH{sub 2}-terminal hydrophobic segment. • The ABCD proteins with the segment are targeted peroxisomes. • The ABCD proteins without the segment are targeted to the endoplasmic reticulum. • The role of the segment in organelle targeting is conserved in eukaryotic organisms. - Abstract: In mammals, four ATP-binding cassette (ABC) proteins belonging to subfamily D have been identified. ABCD1–3 possesses the NH{sub 2}-terminal hydrophobic region and are targeted to peroxisomes, while ABCD4 lacking the region is targeted to the endoplasmic reticulum (ER). Based on hydropathy plot analysis, we found that several eukaryotes have ABCD protein homologs lacking the NH{sub 2}-terminal hydrophobic segment (H0 motif). To investigate whether the role of the NH{sub 2}-terminal H0 motif in subcellular localization is conserved across species, we expressed ABCD proteins from several species (metazoan, plant and fungi) in fusion with GFP in CHO cells and examined their subcellular localization. ABCD proteins possessing the NH{sub 2}-terminal H0 motif were localized to peroxisomes, while ABCD proteins lacking this region lost this capacity. In addition, the deletion of the NH{sub 2}-terminal H0 motif of ABCD protein resulted in their localization to the ER. These results suggest that the role of the NH{sub 2}-terminal H0 motif in organelle targeting is widely conserved in living organisms.

  10. Phylogenetic analysis of the spider mite sub-family Tetranychinae (Acari: Tetranychidae) based on the mitochondrial COI gene and the 18S and the 5' end of the 28S rRNA genes indicates that several genera are polyphyletic.

    Science.gov (United States)

    Matsuda, Tomoko; Morishita, Maiko; Hinomoto, Norihide; Gotoh, Tetsuo

    2014-01-01

    The spider mite sub-family Tetranychinae includes many agricultural pests. The internal transcribed spacer (ITS) region of nuclear ribosomal RNA genes and the cytochrome c oxidase subunit I (COI) gene of mitochondrial DNA have been used for species identification and phylogenetic reconstruction within the sub-family Tetranychinae, although they have not always been successful. The 18S and 28S rRNA genes should be more suitable for resolving higher levels of phylogeny, such as tribes or genera of Tetranychinae because these genes evolve more slowly and are made up of conserved regions and divergent domains. Therefore, we used both the 18S (1,825-1,901 bp) and 28S (the 5' end of 646-743 bp) rRNA genes to infer phylogenetic relationships within the sub-family Tetranychinae with a focus on the tribe Tetranychini. Then, we compared the phylogenetic tree of the 18S and 28S genes with that of the mitochondrial COI gene (618 bp). As observed in previous studies, our phylogeny based on the COI gene was not resolved because of the low bootstrap values for most nodes of the tree. On the other hand, our phylogenetic tree of the 18S and 28S genes revealed several well-supported clades within the sub-family Tetranychinae. The 18S and 28S phylogenetic trees suggest that the tribes Bryobiini, Petrobiini and Eurytetranychini are monophyletic and that the tribe Tetranychini is polyphyletic. At the genus level, six genera for which more than two species were sampled appear to be monophyletic, while four genera (Oligonychus, Tetranychus, Schizotetranychus and Eotetranychus) appear to be polyphyletic. The topology presented here does not fully agree with the current morphology-based taxonomy, so that the diagnostic morphological characters of Tetranychinae need to be reconsidered.

  11. Phylogenetic analysis of the spider mite sub-family Tetranychinae (Acari: Tetranychidae based on the mitochondrial COI gene and the 18S and the 5' end of the 28S rRNA genes indicates that several genera are polyphyletic.

    Directory of Open Access Journals (Sweden)

    Tomoko Matsuda

    Full Text Available The spider mite sub-family Tetranychinae includes many agricultural pests. The internal transcribed spacer (ITS region of nuclear ribosomal RNA genes and the cytochrome c oxidase subunit I (COI gene of mitochondrial DNA have been used for species identification and phylogenetic reconstruction within the sub-family Tetranychinae, although they have not always been successful. The 18S and 28S rRNA genes should be more suitable for resolving higher levels of phylogeny, such as tribes or genera of Tetranychinae because these genes evolve more slowly and are made up of conserved regions and divergent domains. Therefore, we used both the 18S (1,825-1,901 bp and 28S (the 5' end of 646-743 bp rRNA genes to infer phylogenetic relationships within the sub-family Tetranychinae with a focus on the tribe Tetranychini. Then, we compared the phylogenetic tree of the 18S and 28S genes with that of the mitochondrial COI gene (618 bp. As observed in previous studies, our phylogeny based on the COI gene was not resolved because of the low bootstrap values for most nodes of the tree. On the other hand, our phylogenetic tree of the 18S and 28S genes revealed several well-supported clades within the sub-family Tetranychinae. The 18S and 28S phylogenetic trees suggest that the tribes Bryobiini, Petrobiini and Eurytetranychini are monophyletic and that the tribe Tetranychini is polyphyletic. At the genus level, six genera for which more than two species were sampled appear to be monophyletic, while four genera (Oligonychus, Tetranychus, Schizotetranychus and Eotetranychus appear to be polyphyletic. The topology presented here does not fully agree with the current morphology-based taxonomy, so that the diagnostic morphological characters of Tetranychinae need to be reconsidered.

  12. Genetic association of aromatic hydrocarbon receptor (AHR) and cytochrome P450, family 1, subfamily A, polypeptide 1 (CYP1A1) polymorphisms with dioxin blood concentrations among pregnant Japanese women.

    Science.gov (United States)

    Kobayashi, Sumitaka; Sata, Fumihiro; Sasaki, Seiko; Ban, Susumu; Miyashita, Chihiro; Okada, Emiko; Limpar, Mariko; Yoshioka, Eiji; Kajiwara, Jumboku; Todaka, Takashi; Saijo, Yasuaki; Kishi, Reiko

    2013-06-07

    Dioxins are metabolized by cytochrome P450, family 1 (CYP1) via the aromatic hydrocarbon receptor (AHR). We determined whether different blood dioxin concentrations are associated with polymorphisms in AHR (dbSNP ID: rs2066853), AHR repressor (AHRR; rs2292596), CYP1 subfamily A polypeptide 1 (CYP1A1; rs4646903 and rs1048963), CYP1 subfamily A polypeptide 2 (CYP1A2; rs762551), and CYP1 subfamily B polypeptide 1 (CYP1B1; rs1056836) in pregnant Japanese women. These six polymorphisms were detected in 421 healthy pregnant Japanese women. Differences in dioxin exposure concentrations in maternal blood among the genotypes were investigated. Comparisons among the GG, GA, and AA genotypes of AHR showed a significant difference (genotype model: P=0.016 for the mono-ortho polychlorinated biphenyl concentrations and toxicity equivalence quantities [TEQs]). Second, we found a significant association with the dominant genotype model ([TT+TC] vs. CC: P=0.048 for the polychlorinated dibenzo-p-dioxin TEQs; P=0.035 for polychlorinated dibenzofuran TEQs) of CYP1A1 (rs4646903). No significant differences were found among blood dioxin concentrations and polymorphisms in AHRR, CYP1A1 (rs1048963), CYP1A2, and CYP1B1. Thus, polymorphisms in AHR and CYP1A1 (rs4646903) were associated with maternal dioxin concentrations. However, differences in blood dioxin concentrations were relatively low.

  13. The Differential Dimension Polynomial for Characterizable Differential Ideals

    OpenAIRE

    Lange-Hegermann, Markus

    2014-01-01

    We generalize the differential dimension polynomial from prime differential ideals to characterizable differential ideals. Its computation is algorithmic, its degree and leading coefficient remain differential birational invariants, and it decides equality of characterizable differential ideals contained in each other.

  14. Over-expression in Escherichia coli, purification and reconstitution in liposomes of the third member of the OCTN sub-family: The mouse carnitine transporter OCTN3

    Energy Technology Data Exchange (ETDEWEB)

    Scalise, Mariafrancesca; Galluccio, Michele; Pochini, Lorena [Department of Cell Biology, University of Calabria, Via P. Bucci 4c, 87036 Arcavacata di Rende (Italy); Indiveri, Cesare, E-mail: indiveri@unical.it [Department of Cell Biology, University of Calabria, Via P. Bucci 4c, 87036 Arcavacata di Rende (Italy)

    2012-05-25

    Highlights: Black-Right-Pointing-Pointer mOCTN3 transport protein has been cloned in pET-21a(+) and over-expressed in Escherichia coli. Black-Right-Pointing-Pointer The expressed mOCTN3 has been purified to homogeneity by Ni-chelating chromatography. Black-Right-Pointing-Pointer The protein solubilised in Triton X-100 has been reconstituted in liposomes. Black-Right-Pointing-Pointer Recombinant mOCTN3 catalyses transport of carnitine by a uniport mode. -- Abstract: pET-21a(+)-mOCTN3-6His was constructed and used for over-expression in Escherichia coli Rosetta(DE3)pLysS. After IPTG induction a protein with apparent molecular mass of 53 kDa was collected in the insoluble fraction of the cell lysate and purified by Ni{sup 2+}-chelating chromatography with a yield of 2 mg/l of cell culture. The over-expressed protein was identified with mOCTN3 by anti-His antibody and reconstitution in liposomes. mOCTN3 required peculiar conditions for optimal expression and reconstitution in liposomes. The protein catalyzed a time dependent [{sup 3}H]carnitine uptake which was stimulated by intraliposomal ATP and nearly independent of the pH. The K{sub m} for carnitine was 36 {mu}M. [{sup 3}H]carnitine transport was inhibited by carnitine analogues and some Cys and NH{sub 2} reagents. This paper represents the first outcome in over-expressing, in active form, the third member of the OCTN sub-family, mOCTN3, in E. coli.

  15. A REVISION OF THE PLIOCENE NATICIDS OF NORTHERN AND CENTRAL ITALY. II. THE SUBFAMILY NATICINAE: ADDITIONS TO COCHLIS, TANEA AND TECTONATICA

    Directory of Open Access Journals (Sweden)

    LUCA PEDRIALI

    2008-03-01

    Full Text Available The present paper is the second in a series devoted to the revision of the Pliocene naticids of Northern and Central Italy. It concludes the section covering the calcareous operculum-bearing Naticinae and expands to 18 the total number of species and subspecies of this subfamily recovered so far from the Pliocene deposits of Italy. Of the six taxa considered in this study, two (epigloafuniculata and fredianii fully match the characters of the genus Cochlis Röding, 1798, one (koeneni is assigned to the genus Tanea Marwick, 1931, the rest (astensis, prietoi and tectula belong to the genus Tectonatica Sacco, 1890. All the six taxa considered in this paper are described and commented in the systematic account. One, Cochlis fredianii, is proposed as new. In the chapter treating the generic assignment of the studied taxa, the range of Tanea, hitherto used to allocate several Indo-Pacific species, is extended to the Mediterranean Basin as well, and the relations between Tectonatica and Cryptonatica Dall, 1892 are discussed. This study further demonstrates that the morphological characters of the teleoconch are of low significance in species recognition. In fact, should the characters be ranked, the operculum comes first and is the primary element, sufficient to distinguish each species. The protoconch and the color pattern are the second and third relevant attributes that can be used diagnostically for several taxa, but not always. The other shell features appear to be useful tools in separating species only occasionally. Some species lack distinctive shell characters and do require operculate specimens in order to be confidently 

  16. Association with the Plasma Membrane Is Sufficient for Potentiating Catalytic Activity of Regulators of G Protein Signaling (RGS) Proteins of the R7 Subfamily.

    Science.gov (United States)

    Muntean, Brian S; Martemyanov, Kirill A

    2016-03-25

    Regulators of G protein Signaling (RGS) promote deactivation of heterotrimeric G proteins thus controlling the magnitude and kinetics of responses mediated by G protein-coupled receptors (GPCR). In the nervous system, RGS7 and RGS9-2 play essential role in vision, reward processing, and movement control. Both RGS7 and RGS9-2 belong to the R7 subfamily of RGS proteins that form macromolecular complexes with R7-binding protein (R7BP). R7BP targets RGS proteins to the plasma membrane and augments their GTPase-accelerating protein (GAP) activity, ultimately accelerating deactivation of G protein signaling. However, it remains unclear if R7BP serves exclusively as a membrane anchoring subunit or further modulates RGS proteins to increase their GAP activity. To directly answer this question, we utilized a rapidly reversible chemically induced protein dimerization system that enabled us to control RGS localization independent from R7BP in living cells. To monitor kinetics of Gα deactivation, we coupled this strategy with measuring changes in the GAP activity by bioluminescence resonance energy transfer-based assay in a cellular system containing μ-opioid receptor. This approach was used to correlate changes in RGS localization and activity in the presence or absence of R7BP. Strikingly, we observed that RGS activity is augmented by membrane recruitment, in an orientation independent manner with no additional contributions provided by R7BP. These findings argue that the association of R7 RGS proteins with the membrane environment provides a major direct contribution to modulation of their GAP activity.

  17. Prognostic significance and molecular mechanism of ATP-binding cassette subfamily C member 4 in resistance to neoadjuvant radiotherapy of locally advanced rectal carcinoma.

    Directory of Open Access Journals (Sweden)

    Zhiqi Yu

    Full Text Available BACKGROUND: Mechanism of radioresistance in rectal carcinoma remains largely unknown. We aimed to evaluate the predictive role of ATP-binding cassette subfamily C member 4 (ABCC4 in locally advanced rectal carcinoma and explore possible molecular mechanisms by which ABCC4 confers the resistance to neoadjuvant radiotherapy. METHODS: The expression of ABCC4 and P53 mutant in biopsy tissue specimens from 121 locally advanced rectal carcinoma patients was examined using immunohistochemistry. The factors contributing to 3-year overall survival and disease-free survival were evaluated using the Kaplan-Meier method and Cox proportional hazard model. Lentivirus-mediated small hairpin RNA was applied to inhibit ABCC4 expression in colorectal carcinoma cell line RKO, and investigate the radiosensitivity in xenograft model. Intracellular cyclic adenosine monophosphate concentration and cell cycle distribution following irradiation were detected. RESULTS: High expression of ABCC4 and p53 mutant in pretreated tumors, poor pathological response, and high final tumor staging were significant factors independently predicted an unfavorable prognosis of locally advanced rectal carcinoma patients after neoadjuvant radiotherapy. Down-regulation of ABCC4 expression significantly enhanced irradiation-induced suppression of tumor growth in xenograft model. Furthermore, down-regulation of ABCC4 expression enhanced intracellular cyclic adenosine monophosphate production and noticeable deficiency of G1-S phase checkpoint in cell cycle following irradiation. CONCLUSIONS: Our study suggests that ABCC4 serves as a novel predictive biomarker that is responsible for the radioresistance and predicts a poor prognosis for locally advanced rectal carcinoma after neoadjuvant radiotherapy.

  18. pkl1(+)and klp2(+): Two kinesins of the Kar3 subfamily in fission yeast perform different functions in both mitosis and meiosis.

    Science.gov (United States)

    Troxell, C L; Sweezy, M A; West, R R; Reed, K D; Carson, B D; Pidoux, A L; Cande, W Z; McIntosh, J R

    2001-11-01

    We have identified Klp2p, a new kinesin-like protein (KLP) of the KAR3 subfamily in fission yeast. The motor domain of this protein is 61% identical and 71% similar to Pkl1p, another fission yeast KAR3 protein, yet the two enzymes are different in behavior and function. Pkl1p is nuclear throughout the cell cycle, whereas Klp2p is cytoplasmic during interphase. During mitosis Klp2p enters the nucleus where it forms about six chromatin-associated dots. In metaphase-arrested cells these migrate back and forth across the nucleus. During early anaphase they segregate with the chromosomes into two sets of about three, fade, and are replaced by other dots that form on the spindle interzone. Neither klp2(+) nor pkl1(+) is essential, and the double deletion is also wild type for both vegetative and sexual reproduction. Each deletion rescues different alleles of cut7(ts), a KLP that contributes to spindle formation and elongation. When either or both deletions are combined with a dynein deletion, vegetative growth is normal, but sexual reproduction fails: klp2 Delta,dhc1-d1 in karyogamy, pkl1 Delta,dhc1-d1 in multiple phases of meiosis, and the triple deletion in both. Deletion of Klp2p elongates a metaphase-arrested spindle, but pkl1 Delta shortens it. The anaphase spindle of klp2 Delta becomes longer than the cell, leading it to curl around the cell's ends. Apparently, Klp2p promotes spindle disassembly and contributes to the behavior of mitotic chromosomes.

  19. Repression of genes involved in melanocyte differentiation in uveal melanoma

    Science.gov (United States)

    Bergeron, Marjorie-Allison; Champagne, Sophie; Gaudreault, Manon; Deschambeault, Alexandre

    2012-01-01

    Purpose Uveal melanoma (UM) has been the subject of intense interest due to its distinctive metastatic pattern, which involves hematogenous dissemination of cancerous cells toward the liver in 50% of patients. To search for new UM prognostic markers, the Suppressive Subtractive Hybridization (SSH) technique was used to isolate genes that are differentially expressed between UM primary tumors and normal uveal melanocytes (UVM). Methods A subtracted cDNA library was prepared using cDNA from uncultured UM primary tumors and UVM. The expression level of selected genes was further validated by cDNA microarray, semi-quantitative reverse transcription polymerase chain reaction (RT-PCR), and immunofluorescence analyses. Results One hundred-fifteen genes were identified using the SSH technique. Microarray analyses comparing the gene expression profiles of UM primary tumors to UVM validated a significant differential expression for 48% of these genes. The expression pattern of selected genes was then analyzed by semi-quantitative RT–PCR and was found to be consistent with the SSH and cDNA microarray findings. A down-regulation of genes associated with melanocyte differentiation was confirmed in UM primary tumors. Presence of undifferentiated cells in the UM was demonstrated by the expression of stem cell markers ATP-binding cassette sub-family G member 2 (ABCG2) and octamer-binding protein 4 (OCT4). Conclusions We demonstrated that the SSH technique is efficient to detect differentially expressed genes between UM and UVM. The genes identified in this study represent valuable candidates for further functional analysis in UM and should be informative in studying the biology of this tumor. In addition, deregulation of the melanocyte differentiation pathway revealed the presence of UM cells exhibiting a stem cell-like phenotype. PMID:22815634

  20. Axiomatic differential geometry II-2 - differential forms

    OpenAIRE

    Nishimura, Hirokazu

    2013-01-01

    We refurbish our axiomatics of differential geometry introduced in [Mathematics for Applications,, 1 (2012), 171-182]. Then the notion of Euclideaness can naturally be formulated. The principal objective in this paper is to present an adaptation of our theory of differential forms developed in [International Journal of Pure and Applied Mathematics, 64 (2010), 85-102] to our present axiomatic framework.

  1. Axiomatic Differential Geometry Ⅱ-2: Differential Forms

    OpenAIRE

    Nishimura, Hirokazu

    2013-01-01

    We refurbish our axiomatics of differential geometry introduced in [arXiv 1203.3911]. Then the notion of Euclideaness can naturally be formulated. The principal objective in this paper is to present an adaptation of our theory of differential forms developed in [International Journal of Pure and Applied Mathematics, 64 (2010), 85-102] to our present axiomatic framework.

  2. Symposium on Differential Geometry and Differential Equations

    CERN Document Server

    Berger, Marcel; Bryant, Robert

    1987-01-01

    The DD6 Symposium was, like its predecessors DD1 to DD5 both a research symposium and a summer seminar and concentrated on differential geometry. This volume contains a selection of the invited papers and some additional contributions. They cover recent advances and principal trends in current research in differential geometry.

  3. Automatic differentiation bibliography

    Energy Technology Data Exchange (ETDEWEB)

    Corliss, G.F. (comp.)

    1992-07-01

    This is a bibliography of work related to automatic differentiation. Automatic differentiation is a technique for the fast, accurate propagation of derivative values using the chain rule. It is neither symbolic nor numeric. Automatic differentiation is a fundamental tool for scientific computation, with applications in optimization, nonlinear equations, nonlinear least squares approximation, stiff ordinary differential equation, partial differential equations, continuation methods, and sensitivity analysis. This report is an updated version of the bibliography which originally appeared in Automatic Differentiation of Algorithms: Theory, Implementation, and Application.

  4. Fast Differential Adder

    Science.gov (United States)

    Arditti, Mort A.; Silva, Rosemary

    1993-01-01

    Differential adding circuit (or, equivalently, subtracting circuit) faster and consumes less power because it contains only one differential amplifier. Suitable for use in high-frequency-switching, high power-regulating circuit.

  5. functional-differential inequalities

    Directory of Open Access Journals (Sweden)

    Ludwik Byszewski

    1995-01-01

    Full Text Available A theorem about a system of strong impulsive degenerate nonlinear parabolic functional-differential inequalities in an arbitrary parabolic set is proved. As a consequence of the theorem, some theorems about impulsive degenerate nonlinear parabolic differential inequalities and the uniqueness of a classical solution of an impulsive degenerate nonlinear parabolic differential problem are established.

  6. Partial Differential Equations

    CERN Document Server

    1988-01-01

    The volume contains a selection of papers presented at the 7th Symposium on differential geometry and differential equations (DD7) held at the Nankai Institute of Mathematics, Tianjin, China, in 1986. Most of the contributions are original research papers on topics including elliptic equations, hyperbolic equations, evolution equations, non-linear equations from differential geometry and mechanics, micro-local analysis.

  7. Using Differentials to Differentiate Trigonometric and Exponential Functions

    Science.gov (United States)

    Dray, Tevian

    2013-01-01

    Starting from geometric definitions, we show how differentials can be used to differentiate trigonometric and exponential functions without limits, numerical estimates, solutions of differential equations, or integration.

  8. A new species of Glaphyropoma: the first subterranean copionodontine catfish and the first occurrence of opercular odontodes in the subfamily (Siluriformes: Trichomycteridae

    Directory of Open Access Journals (Sweden)

    Maria Elina Bichuette

    2008-01-01

    Full Text Available A new species of the rare copionodontine genus Glaphyropoma is described from subterranean waters in the Diamantina Plateau, Bahia State, central northeastern Brazil. This is the first troglomorphic species in the subfamily Copionodontinae. It is distinguished from all other copionodontines by the presence of opercular odontodes, and further distinguished from its only congener, G. rodriguesi, by the reduction of dark integumentary pigmentation. The new species shares the single synapomorphy previously proposed for Glaphyropoma, the marked narrowing of the first hypobranchial and indirect character evidence also supports its inclusion in the genus. The presence of opercular odontodes in the new species, in combination with a reviewed hypothesis of sister group relationship between Copionodontinae and Trichogeninae, indicate that the absence of opercular odontodes in previously-known copionodontines is secondary, rather than primitive.Uma nova espécie do raro gênero de Copionodontinae Glaphyropoma é descrita de águas subterrâneas da Chapada Diamantina, estado da Bahia, região central do Nordeste Brasileiro. Esta é a primeira espécie troglomórfica na subfamília Copionodontinae. Distingue-se de todos os outros Copionodontinae pela presença de odontódeos operculares, e de seu único congênere, G. rodriguesi, também pela redução de pigmentação tegumentar. A nova espécie apresenta a única sinapomorfia previamente proposta para Glaphyropoma, um estreitamento acentuado do primeiro hipobranquial e evidência indireta de outros caracteres também suportam sua inclusão no gênero. A presença de odontódeos operculares na nova espécie, em combinação com uma hipótese revisada de grupo-irmão entre Copionodontinae e Trichogeninae, indica que a ausência de odontódeos operculares nos Copionodontinae previamente conhecidos é secundária e não primitiva.

  9. Differential genes in adipocytes induced from polycystic and non-polycystic ovary syndrome-derived human embryonic stem cells.

    Science.gov (United States)

    Wang, Fang; Liu, Wei-Wei; Chen, Xue-Mei; Kong, Hui-Juan; Li, Jing; Sun, Ying-Pu

    2014-06-01

    We explored the molecular mechanisms of obesity and insulin resistance in patients with polycystic ovary syndrome (PCOS) using a human embryonic stem cell model (hESCs). Three PCOS-derived and one non-PCOS-derived hESC lines were induced into adipocytes, and then total RNA was extracted. The differentially expressed PCOS-derived and non-PCOS-derived adipocytes genes were identified using the Boao Biological human V 2.0 whole genome oligonucleotide microarray. Signals of interest were then validated by real-time PCR. A total of 153 differential genes were expressed of which 91 genes were up-regulated and 62 down-regulated. Nuclear receptor subfamily 0, group B, member 2 (NR0B2) was an up-regulated gene, and the GeneChip CapitalBio® Molecule Annotation System V4.0 indicated that it was associated with obesity and diabetes (Ratio ≥ 2.0X). Multiple genes are involved in PCOS. Nuclear receptor subfamily 0, group B, member 2 may play a role in obesity and insulin resistance in patients with PCOS.

  10. Amphibious Shelter-Builder Oniscidea Species from the New World with Description of a New Subfamily, a New Genus and a New Species from Brazilian Cave (Isopoda, Synocheta, Styloniscidae)

    Science.gov (United States)

    2015-01-01

    The new subfamily Iuiuniscinae, Styloniscidae, is erected for the new genus Iuiuniscus and the new species I. iuiuensis, which is described from cave of the State of Bahia, Northeastern Brazil. A special ecological character is shown here for the first time for a New World Oniscidea: the construction of mud shelters. An introduction addressing the systematics of Synocheta with emphasis on Styloniscidae Vandel, 1952 is provided, as well as general comments about the dependence of water in some Oniscidea and ecological traits of amphibious Synocheta. The problems referring to nomenclature, taxonomy and the interrelationships in Styloniscidae are discussed. PMID:25992909

  11. [Revision of of the subfamily of Metaracoelophryinae de Puytorac 1972 (Oligohymenophora: Hoplytophryida: Hoplytophryidae), astome ciliates of the digestive tract of Oligochaeta worms of Africa: description of five new species].

    Science.gov (United States)

    Fokam, Z; Ngassam, P; Nana, P A; Bricheux, G; Bouchard, P; Sime Ngando, T

    2012-02-01

    Five new species belonging to the astome ciliates, living in the digestive tract of Oligochaeta worms belonging to the genus Alma from Cameroon, have been described. The techniques used are: vital staining, staining of the nucleus with Diamidino Phenyl Indol (DAPI), scanning electron microscopy and silver staining method (Fernandez Galiano, 1976, 1994). This work confirms the presence of the genus Paracoelophrya and Dicoelophrya in the digestive track of the oligochaete Alma from Gabon and Cameroon; it helps to understand the general taxonomy of this Metaracoelophryinae subfamily. Moreover, the homogeneity of this group is confirmed and the phylogenetic relationship inside the Hoplitophryida order need more studies to be solved.

  12. Fundamentals of differential beamforming

    CERN Document Server

    Benesty, Jacob; Pan, Chao

    2016-01-01

    This book provides a systematic study of the fundamental theory and methods of beamforming with differential microphone arrays (DMAs), or differential beamforming in short. It begins with a brief overview of differential beamforming and some popularly used DMA beampatterns such as the dipole, cardioid, hypercardioid, and supercardioid, before providing essential background knowledge on orthogonal functions and orthogonal polynomials, which form the basis of differential beamforming. From a physical perspective, a DMA of a given order is defined as an array that measures the differential acoustic pressure field of that order; such an array has a beampattern in the form of a polynomial whose degree is equal to the DMA order. Therefore, the fundamental and core problem of differential beamforming boils down to the design of beampatterns with orthogonal polynomials. But certain constraints also have to be considered so that the resulting beamformer does not seriously amplify the sensors’ self noise and the mism...

  13. A putative autonomous 20.5 kb-CACTA transposon insertion in an F3'H allele identifies a new CACTA transposon subfamily in Glycine max

    Directory of Open Access Journals (Sweden)

    Vodkin Lila

    2008-12-01

    in the gray trichome allele t*. Conclusion The molecular characterization of a 20.5 kb insertion in the flavonoid 3'-hydroxylase (F3'H gene of a soybean gray pubescence allele (t* identified the structure of a CACTA transposon designated Tgmt*. Besides the terminal inverted repeats and subterminal repeated motifs,Tgmt* encoded a large gene with two putative functions that are required for excision and transposition of a CACTA element, a transposase and the DNA binding protein known to associate to the subterminal repeated motifs. The degree of dissimilarity between Tgmt* transposase and subterminal repeated motifs with those of previously characterized defective CACTA elements (Tgm1-7 were evidence of the existence of two subfamilies of CACTA transposons in soybean, an observation not previously reported in other plants. In addition, our analyses of a genetically active and potentially autonomous element sheds light on the complete structure of a soybean element that is useful for annotation of the repetitive fraction of the soybean genome sequence and may prove useful for transposon tagging or transposon display experiments in different genetic lines.

  14. Developmental Partial Differential Equations

    OpenAIRE

    Duteil, Nastassia Pouradier; Rossi, Francesco; Boscain, Ugo; Piccoli, Benedetto

    2015-01-01

    In this paper, we introduce the concept of Developmental Partial Differential Equation (DPDE), which consists of a Partial Differential Equation (PDE) on a time-varying manifold with complete coupling between the PDE and the manifold's evolution. In other words, the manifold's evolution depends on the solution to the PDE, and vice versa the differential operator of the PDE depends on the manifold's geometry. DPDE is used to study a diffusion equation with source on a growing surface whose gro...

  15. High resolution differential thermometer

    Directory of Open Access Journals (Sweden)

    Gotra Z. Yu.

    2009-11-01

    Full Text Available Main schematic solutions of differential thermometers with measurement resolution about 0.001°C are considered. Differential temperature primary transducer realized on a transistor differential circuit in microampere mode. Analytic calculation and schematic mathematic simulation of primary transducer are fulfilled. Signal transducer is realized on a high precision Zero-Drift Single-Supply Rail-to-Rail operation amplifier AD8552 and 24-Bit S-D microconverter ADuC834.

  16. Singular stochastic differential equations

    CERN Document Server

    Cherny, Alexander S

    2005-01-01

    The authors introduce, in this research monograph on stochastic differential equations, a class of points termed isolated singular points. Stochastic differential equations possessing such points (called singular stochastic differential equations here) arise often in theory and in applications. However, known conditions for the existence and uniqueness of a solution typically fail for such equations. The book concentrates on the study of the existence, the uniqueness, and, what is most important, on the qualitative behaviour of solutions of singular stochastic differential equations. This is done by providing a qualitative classification of isolated singular points, into 48 possible types.

  17. Differential expression of members of the E2F family of transcription factors in rodent testes

    Directory of Open Access Journals (Sweden)

    Toppari Jorma

    2006-12-01

    profile of stage-specificity compared to E2F-1, which is probably related to its prevalence and role in Sertoli cells. IHC of rat testis indicates that localization of E2F-5 is distinct from that of E2F-4 and overlaps those of E2F-1 and E2F-2. Conclusion The E2F-1 represents the subfamily of transcription factors required during stages of DNA replication and gene expression for development of germ cells and the E2F-4 represents the subfamily of transcription factors that help maintain gene expression for a terminally differentiated state within the testis.

  18. Differentiering - Hvorfor & hvordan?

    DEFF Research Database (Denmark)

    Pedersen, Michael Svendsen

    Rapporten indeholder en introduktion til differentiering i undervisningen i dansk som andetsprog, hvor der lægges vægt på at differentiering ikke kan reduceres til nogle "teknikker" eller "værktøjer", men er en generel tilgang til undervisning der har deltagernes ressourcer og ligeværd som udgang...

  19. Equivalence of Differential System

    Institute of Scientific and Technical Information of China (English)

    Zheng-xin Zhou

    2004-01-01

    Using refiecting function of Mironenko we construct some differential systems which are equivalent to the given differential system.This gives us an opportunity to find out the monodromic matrix of these periodi csystems which are not integrable in finite terms.

  20. On Quadratic Differential Forms

    NARCIS (Netherlands)

    Willems, J.C.; Trentelman, H.L.

    1998-01-01

    This paper develops a theory around the notion of quadratic differential forms in the context of linear differential systems. In many applications, we need to not only understand the behavior of the system variables but also the behavior of certain functionals of these variables. The obvious cases w

  1. Lifting the Differentiation Embargo.

    Science.gov (United States)

    Latif, Anne-Louise; Holyoake, Tessa L

    2016-09-22

    Effective differentiation therapy for acute myeloid leukemia (AML) has been restricted to a small subset of patients with one defined genetic abnormality. Using an unbiased small molecule screen, Sykes et al. now identify a mechanism of de-repression of differentiation in several models of AML driven by distinct genetic drivers.

  2. Automatic Differentiation Package

    Energy Technology Data Exchange (ETDEWEB)

    2007-03-01

    Sacado is an automatic differentiation package for C++ codes using operator overloading and C++ templating. Sacado provide forward, reverse, and Taylor polynomial automatic differentiation classes and utilities for incorporating these classes into C++ codes. Users can compute derivatives of computations arising in engineering and scientific applications, including nonlinear equation solving, time integration, sensitivity analysis, stability analysis, optimization and uncertainity quantification.

  3. "Nowhere" differentiable horizons

    CERN Document Server

    Chrúsciel, P T

    1996-01-01

    It is folklore knowledge amongst general relativists that horizons are well behaved, continuously differentiable hypersurfaces except perhaps on a negligible subset one needs not to bother with. We show that this is not the case, by constructing a Cauchy horizon, as well as a black hole event horizon, which contain no open subset on which they are differentiable.

  4. Differential equations for dummies

    CERN Document Server

    Holzner, Steven

    2008-01-01

    The fun and easy way to understand and solve complex equations Many of the fundamental laws of physics, chemistry, biology, and economics can be formulated as differential equations. This plain-English guide explores the many applications of this mathematical tool and shows how differential equations can help us understand the world around us. Differential Equations For Dummies is the perfect companion for a college differential equations course and is an ideal supplemental resource for other calculus classes as well as science and engineering courses. It offers step-by-step techniques, practical tips, numerous exercises, and clear, concise examples to help readers improve their differential equation-solving skills and boost their test scores.

  5. Randomness and Differentiability

    CERN Document Server

    Brattka, Vasco; Nies, André

    2011-01-01

    We characterize some major algorithmic randomness notions via differentiability of effective functions. (1) We show that a real number z in [0,1] is computably random if and only if every nondecreasing computable function [0,1]->R is differentiable at z. (2) A real number z in [0,1] is weakly 2-random if and only if every almost everywhere differentiable computable function [0,1]->R is differentiable at z. (3) Recasting results of the constructivist Demuth (1975) in classical language, we show that a real z is ML random if and only if every computable function of bounded variation is differentiable at z, and similarly for absolutely continuous functions. We also use the analytic methods to show that computable randomness of a real is base invariant, and to derive preservation results for randomness notions.

  6. 25-Hydroxyvitamin D3 induces osteogenic differentiation of human mesenchymal stem cells

    Science.gov (United States)

    Lou, Yan-Ru; Toh, Tai Chong; Tee, Yee Han; Yu, Hanry

    2017-01-01

    25-Hydroxyvitamin D3 [25(OH)D3] has recently been found to be an active hormone. Its biological actions are demonstrated in various cell types. 25(OH)D3 deficiency results in failure in bone formation and skeletal deformation. Here, we investigated the effect of 25(OH)D3 on osteogenic differentiation of human mesenchymal stem cells (hMSCs). We also studied the effect of 1α,25-dihydroxyvitamin D3 [1α,25-(OH)2D3], a metabolite of 25(OH)D3. One of the vitamin D responsive genes, 25(OH)D3-24-hydroxylase (cytochrome P450 family 24 subfamily A member 1) mRNA expression is up-regulated by 25(OH)D3 at 250–500 nM and by 1α,25-(OH)2D3 at 1–10 nM. 25(OH)D3 and 1α,25-(OH)2D3 at a time-dependent manner alter cell morphology towards osteoblast-associated characteristics. The osteogenic markers, alkaline phosphatase, secreted phosphoprotein 1 (osteopontin), and bone gamma-carboxyglutamate protein (osteocalcin) are increased by 25(OH)D3 and 1α,25-(OH)2D3 in a dose-dependent manner. Finally, mineralisation is significantly increased by 25(OH)D3 but not by 1α,25-(OH)2D3. Moreover, we found that hMSCs express very low level of 25(OH)D3-1α-hydroxylase (cytochrome P450 family 27 subfamily B member 1), and there is no detectable 1α,25-(OH)2D3 product. Taken together, our findings provide evidence that 25(OH)D3 at 250–500 nM can induce osteogenic differentiation and that 25(OH)D3 has great potential for cell-based bone tissue engineering. PMID:28211493

  7. Linking Diversity and Differentiation

    Directory of Open Access Journals (Sweden)

    Hans-Rolf Gregorius

    2010-03-01

    Full Text Available Generally speaking, the term differentiation refers to differences between collections for the distribution of specified traits of their members, while diversity deals with (effective numbers of trait states (types. Counting numbers of types implies discrete traits such as alleles and genotypes in population genetics or species and taxa in ecology. Comparisons between the concepts of differentiation and diversity therefore primarily refer to discrete traits. Diversity is related to differentiation through the idea that the total diversity of a subdivided collection should be composed of the diversity within the subcollections and a complement called “diversity between subcollections”. The idea goes back to the perception that the mixing of differentiated collections increases diversity. Several existing concepts of “diversity between subcollections” are based on this idea. Among them, β-diversity and fixation (inadvertently called differentiation are the most prominent in ecology and in population genetics, respectively. The pertaining measures are shown to quantify the effect of differentiation in terms of diversity components, though from a dual perspective: the classical perspective of differentiation between collections for their type compositions, and the reverse perspective of differentiation between types for their collection affiliations. A series of measures of diversity-oriented differentiation is presented that consider this dual perspective at two levels of diversity partitioning: the overall type or subcollection diversity and the joint type-subcollection diversity. It turns out that, in contrast with common notions, the measures of fixation (such as FST or GST refer to the perspective of type rather than subcollection differentiation. This unexpected observation strongly suggests that the popular interpretations of fixation measures must be reconsidered.

  8. Systematics and phylogeny of the Neotropical treehopper subfamily Nicomiinae (Hemiptera, Membracidae Sistemática e filogenia das cigarrinhas neotropicais da subfamília Nicomiinae (Hemiptera, Membracidae

    Directory of Open Access Journals (Sweden)

    Jesse L. Albertson

    2005-03-01

    Full Text Available Morphological characters of adults of the treehopper subfamily Nicomiinae Haupt, 1929 (Hemiptera, Membracidae including seven genera (Eudonica gen. nov.; Euwalkeria Goding, 1926; Holdgatiella Evans, 1962; Nicomia Stål, 1858; Nodonica Dietrich, McKamey& Deitz, 2001; Stalomia gen. nov.; and Tolania Stål, 1858 and 22 species (16 new are described and illustrated. Keys are provided for genera and for species of Euwalkeria, Holdgatiella, and Nicomia. Nomenclatural changes, based on study of the primary type material of 15 species, include three new combinations, one new synonymy, and reinstatement of one junior synonym. Eudonica has one species, Eudonica nanella sp. nov.; Euwalkeria has five species, including four new species: E. colorata sp. nov., E. distincta sp. nov., E. perdita sp. nov., E. rubrica sp. nov.; Holdgatiella has two species, one of which is described as new: Holdgatiella chiloensis sp. nov.; Nicomia has twelve species, nine of which are described as new: N. buccina sp. nov., N. harenosa sp. nov., N. inscripta sp. nov., N. jucunda sp. nov., N. monticola sp. nov., N. nigrifasciata sp. nov., N. notidana sp. nov., N. pulchella sp. nov., N. serrata sp. nov.; Nodonica has one species, Nodonica bispinigera Dietrich, McKamey & Deitz; and Stalomia has one species, Stalomia veruta sp. nov. Tolania contains eleven previously described species and nearly 60 new species, which will be treated in a later publication. Three new combinations are proposed: one species described in Nicomia is placed in the tribe Abelini (Centrotinae as Abelus retrospinosus (Lethierry comb. nov.; one species previously placed in Nicomia is transferred to the genus Tolania as T. obliqua (Walker, 1858, comb. nov.; one species described in Holdgatiella is placed in the genus Tolania as T. stria (Cryan & Deitz, 2002, comb. nov. One new synonymy is proposed: Hoplophera [sic] cicadoides Walker, 1862, syn. nov., a junior synonym of Nicomia interrupta Stål, 1858. Nicomia

  9. Hyperbolic partial differential equations

    CERN Document Server

    Witten, Matthew

    1986-01-01

    Hyperbolic Partial Differential Equations III is a refereed journal issue that explores the applications, theory, and/or applied methods related to hyperbolic partial differential equations, or problems arising out of hyperbolic partial differential equations, in any area of research. This journal issue is interested in all types of articles in terms of review, mini-monograph, standard study, or short communication. Some studies presented in this journal include discretization of ideal fluid dynamics in the Eulerian representation; a Riemann problem in gas dynamics with bifurcation; periodic M

  10. Theory of differential equations

    CERN Document Server

    Gel'fand, I M

    1967-01-01

    Generalized Functions, Volume 3: Theory of Differential Equations focuses on the application of generalized functions to problems of the theory of partial differential equations.This book discusses the problems of determining uniqueness and correctness classes for solutions of the Cauchy problem for systems with constant coefficients and eigenfunction expansions for self-adjoint differential operators. The topics covered include the bounded operators in spaces of type W, Cauchy problem in a topological vector space, and theorem of the Phragmén-Lindelöf type. The correctness classes for the Cau

  11. Beginning partial differential equations

    CERN Document Server

    O'Neil, Peter V

    2011-01-01

    A rigorous, yet accessible, introduction to partial differential equations-updated in a valuable new edition Beginning Partial Differential Equations, Second Edition provides a comprehensive introduction to partial differential equations (PDEs) with a special focus on the significance of characteristics, solutions by Fourier series, integrals and transforms, properties and physical interpretations of solutions, and a transition to the modern function space approach to PDEs. With its breadth of coverage, this new edition continues to present a broad introduction to the field, while also addres

  12. Differentiation transforming system

    Institute of Scientific and Technical Information of China (English)

    Qiang Cheng; Haibin Zhang; Bin Wang; Yonghua Zhao

    2009-01-01

    The differentiation transforming(DFT)system is developed to produce the tangent linear codes,which is used to calculate the Jacobian-and the Hessian-vector products with no truncation errors.This paper first gives the introduction of the functionality and features of the DFT system,and then discusses several techniques for the implementation of automatic differentiation tools,including data dependence analysis,singular differentiation and code optimization.Finally,the codes generated with DFT used in several applications have been demonstrated.

  13. Differential equations problem solver

    CERN Document Server

    Arterburn, David R

    2012-01-01

    REA's Problem Solvers is a series of useful, practical, and informative study guides. Each title in the series is complete step-by-step solution guide. The Differential Equations Problem Solver enables students to solve difficult problems by showing them step-by-step solutions to Differential Equations problems. The Problem Solvers cover material ranging from the elementary to the advanced and make excellent review books and textbook companions. They're perfect for undergraduate and graduate studies.The Differential Equations Problem Solver is the perfect resource for any class, any exam, and

  14. Ordinary differential equations

    CERN Document Server

    Miller, Richard K

    1982-01-01

    Ordinary Differential Equations is an outgrowth of courses taught for a number of years at Iowa State University in the mathematics and the electrical engineering departments. It is intended as a text for a first graduate course in differential equations for students in mathematics, engineering, and the sciences. Although differential equations is an old, traditional, and well-established subject, the diverse backgrounds and interests of the students in a typical modern-day course cause problems in the selection and method of presentation of material. In order to compensate for this diversity,

  15. Ordinary differential equations

    CERN Document Server

    Pontryagin, Lev Semenovich

    1962-01-01

    Ordinary Differential Equations presents the study of the system of ordinary differential equations and its applications to engineering. The book is designed to serve as a first course in differential equations. Importance is given to the linear equation with constant coefficients; stability theory; use of matrices and linear algebra; and the introduction to the Lyapunov theory. Engineering problems such as the Watt regulator for a steam engine and the vacuum-tube circuit are also presented. Engineers, mathematicians, and engineering students will find the book invaluable.

  16. Differential Equations as Actions

    DEFF Research Database (Denmark)

    Ronkko, Mauno; Ravn, Anders P.

    1997-01-01

    We extend a conventional action system with a primitive action consisting of a differential equation and an evolution invariant. The semantics is given by a predicate transformer. The weakest liberal precondition is chosen, because it is not always desirable that steps corresponding to differential...... actions shall terminate. It is shown that the proposed differential action has a semantics which corresponds to a discrete approximation when the discrete step size goes to zero. The extension gives action systems the power to model real-time clocks and continuous evolutions within hybrid systems....

  17. Uncertain differential equations

    CERN Document Server

    Yao, Kai

    2016-01-01

    This book introduces readers to the basic concepts of and latest findings in the area of differential equations with uncertain factors. It covers the analytic method and numerical method for solving uncertain differential equations, as well as their applications in the field of finance. Furthermore, the book provides a number of new potential research directions for uncertain differential equation. It will be of interest to researchers, engineers and students in the fields of mathematics, information science, operations research, industrial engineering, computer science, artificial intelligence, automation, economics, and management science.

  18. Elementary differential geometry

    CERN Document Server

    Pressley, Andrew

    2001-01-01

    Curves and surfaces are objects that everyone can see, and many of the questions that can be asked about them are natural and easily understood Differential geometry is concerned with the precise mathematical formulation of some of these questions, and with trying to answer them using calculus techniques It is a subject that contains some of the most beautiful and profound results in mathematics yet many of these are accessible to higher-level undergraduates Elementary Differential Geometry presents the main results in the differential geometry of curves and surfaces while keeping the prerequisites to an absolute minimum Nothing more than first courses in linear algebra and multivariate calculus are required, and the most direct and straightforward approach is used at all times Numerous diagrams illustrate both the ideas in the text and the examples of curves and surfaces discussed there The book will provide an invaluable resource to all those taking a first course in differential geometry, for their lecture...

  19. Key to the subfamilies, tribes and genera of adult Dytiscidae of Argentina (Coleoptera: Adephaga Clave para los adultos de las subfamilias, tribus y géneros de Dytiscidae de la Argentina (Coleoptera: Adephaga

    Directory of Open Access Journals (Sweden)

    María L. Libonatti

    2011-12-01

    Full Text Available Dytiscids constitute the world's most speciose family of water beetles, whose identifi cation in Argentina is problematic with current keys. In this work, a key (both in English and Spanish to the eight subfamilies, 16 tribes and 31 genera of adult Dytiscidae of Argentina is presented. The key was constructed using stable qualitative characters of the external morphology and chaetotaxy, easily visualizable and interpretable. Characters such as size and shape of the body, color pattern and geographic distribution were also used. Illustrations of a great number of morphological structures as well as SEM micrographs were included to aid in the interpretation of the text. One subfamily (Hydrodytinae and fi ve genera (Agaporomorphus Zimmermann, Bidessodes Régimbart, Hydrodytes Miller, Queda Sharp and an unpublished genus of the subfamily Laccophilinae are cited for the fi rst time for Argentina.Los ditíscidos constituyen la familia más numerosa de escarabajos acuáticos a nivel mundial, cuya identifi cación en la Argentina resulta problemática con las claves actuales. En este trabajo, se presenta una clave (en inglés y español para los adultos de las ocho subfamilias, 16 tribus y 31 géneros de Dytiscidae de la Argentina. La clave fue construida priorizando la inclusión de caracteres cualitativos estables de la morfología externa y quetotaxia, fácilmente visibles e interpretables. También, se utilizaron caracteres como el tamaño y la forma del cuerpo, el patrón de coloración y la distribución geográfi ca. Se incluyeron ilustraciones de un gran número de estructuras morfológicas y fotografías tomadas con el microscopio electrónico, para ayudar a la interpretación del texto. Se citan, por primera vez para la Argentina, una subfamilia (Hydrodytinae y cinco géneros (Agaporomorphus Zimmermann, Bidessodes Régimbart, Hydrodytes Miller, Queda Sharp y un género inédito de la subfamilia Laccophilinae.

  20. Stochastic partial differential equations

    CERN Document Server

    Chow, Pao-Liu

    2014-01-01

    Preliminaries Introduction Some Examples Brownian Motions and Martingales Stochastic Integrals Stochastic Differential Equations of Itô Type Lévy Processes and Stochastic IntegralsStochastic Differential Equations of Lévy Type Comments Scalar Equations of First Order Introduction Generalized Itô's Formula Linear Stochastic Equations Quasilinear Equations General Remarks Stochastic Parabolic Equations Introduction Preliminaries Solution of Stochastic Heat EquationLinear Equations with Additive Noise Some Regularity Properties Stochastic Reaction-Diffusion Equations Parabolic Equations with Grad

  1. Differential topology an introduction

    CERN Document Server

    Gauld, David B

    2006-01-01

    Offering classroom-proven results, Differential Topology presents an introduction to point set topology via a naive version of nearness space. Its treatment encompasses a general study of surgery, laying a solid foundation for further study and greatly simplifying the classification of surfaces.This self-contained treatment features 88 helpful illustrations. Its subjects include topological spaces and properties, some advanced calculus, differentiable manifolds, orientability, submanifolds and an embedding theorem, and tangent spaces. Additional topics comprise vector fields and integral curv

  2. Beginning partial differential equations

    CERN Document Server

    O'Neil, Peter V

    2014-01-01

    A broad introduction to PDEs with an emphasis on specialized topics and applications occurring in a variety of fields Featuring a thoroughly revised presentation of topics, Beginning Partial Differential Equations, Third Edition provides a challenging, yet accessible,combination of techniques, applications, and introductory theory on the subjectof partial differential equations. The new edition offers nonstandard coverageon material including Burger's equation, the telegraph equation, damped wavemotion, and the use of characteristics to solve nonhomogeneous problems. The Third Edition is or

  3. Ordinary differential equations

    CERN Document Server

    Greenberg, Michael D

    2014-01-01

    Features a balance between theory, proofs, and examples and provides applications across diverse fields of study Ordinary Differential Equations presents a thorough discussion of first-order differential equations and progresses to equations of higher order. The book transitions smoothly from first-order to higher-order equations, allowing readers to develop a complete understanding of the related theory. Featuring diverse and interesting applications from engineering, bioengineering, ecology, and biology, the book anticipates potential difficulties in understanding the various solution steps

  4. A single amino acid substitution in IIIf subfamily of basic helix-loop-helix transcription factor AtMYC1 leads to trichome and root hair patterning defects by abolishing its interaction with partner proteins in Arabidopsis.

    Science.gov (United States)

    Zhao, Hongtao; Wang, Xiaoxue; Zhu, Dandan; Cui, Sujuan; Li, Xia; Cao, Ying; Ma, Ligeng

    2012-04-20

    Plant trichomes and root hairs are powerful models for the study of cell fate determination. In Arabidopsis thaliana, trichome and root hair initiation requires a combination of three groups of proteins, including the WD40 repeat protein transparent TESTA GLABRA1 (TTG1), R2R3 repeat MYB protein GLABRA1 (GL1), or werewolf (WER) and the IIIf subfamily of basic helix-loop-helix (bHLH) protein GLABRA3 (GL3) or enhancer of GLABRA3 (EGL3). The bHLH component acts as a docking site for TTG1 and MYB proteins. Here, we isolated a mutant showing defects in trichome and root hair patterning that carried a point mutation (R173H) in AtMYC1 that encodes the fourth member of IIIf bHLH family protein. Genetic analysis revealed partial redundant yet distinct function between AtMYC1 and GL3/EGL3. GLABRA2 (GL2), an important transcription factor involved in trichome and root hair control, was down-regulated in Atmyc1 plants, suggesting the requirement of AtMYC1 for appropriate GL2 transcription. Like its homologs, AtMYC1 formed a complex with TTG1 and MYB proteins but did not dimerized. In addition, the interaction of AtMYC1 with MYB proteins and TTG1 was abrogated by the R173H substitution in Atmyc1-1. We found that this amino acid (Arg) is conserved in the AtMYC1 homologs GL3/EGL3 and that it is essential for their interaction with MYB proteins and for their proper functions. Our findings indicate that AtMYC1 is an important regulator of trichome and root hair initiation, and they reveal a novel amino acid necessary for protein-protein interactions and gene function in IIIf subfamily bHLH transcription factors.

  5. Differentiation-inducing activity of lupeol, a lupane-type triterpene from Chinese dandelion root (Hokouei-kon), on a mouse melanoma cell line.

    Science.gov (United States)

    Hata, K; Ishikawa, K; Hori, K; Konishi, T

    2000-08-01

    We examined the differentiation-inducing effects of extracts of 49 wild plants, 25 types of seaweed and 26 mushrooms in Akita on the human leukemia cell line HL60 and a B16 mouse melanoma-derived sub-clone with high differentiation capability (B16 2F2). Differentiation inducers of HL60 cells such as retinoic acid, showed no effects on the differentiation of B16 2F2 cells. Furthermore, chemical compounds known to be inducers of B16 cells, did not induce differentiation of HL60 cells. Screening tests showed that the differentiation of HL60 cells was induced by extracts of 28 wild plants, 10 types of seaweed and 2 mushrooms, and melanogenesis of B16 2F2 cells was increased by extracts of 21 wild plants, 8 types of seaweed and 7 mushrooms. All of the alcoholic extracts of plants belonging to the subfamily Cichorioideae of the family Compositae caused cell differentiation of the melanoma cell line. The extracts of Chinese dandelion root, also inhibited cell growth and induced melanogenesis of B16 2F2 cells. We isolated the active compound from ethanol extracts of the crude drug. Chemical and physical data for the active compound were identical with those for lupeol, a lupane-type triterpene.

  6. Differentially Private Spatial Decompositions

    CERN Document Server

    Cormode, Graham; Shen, Entong; Srivastava, Divesh; Yu, Ting

    2011-01-01

    Differential privacy has recently emerged as the de facto standard for private data release. This makes it possible to provide strong theoretical guarantees on the privacy and utility of released data. While it is well-known how to release data based on counts and simple functions under this guarantee, it remains to provide general purpose techniques to release different kinds of data. In this paper, we focus on spatial data such as locations and more generally any data that can be indexed by a tree structure. Directly applying existing differential privacy methods to this type of data simply generates noise. Instead, we introduce a new class of "private spatial decompositions": these adapt standard spatial indexing methods such as quadtrees and kd-trees to provide a private description of the data distribution. Equipping such structures with differential privacy requires several steps to ensure that they provide meaningful privacy guarantees. Various primitives, such as choosing splitting points and describi...

  7. A convenient differential category

    CERN Document Server

    Blute, Richard; Tasson, Christine

    2010-01-01

    In this paper, we show that the category of Mackey-complete, separated, topological convex bornological vector spaces and bornological linear maps is a differential category. Such spaces were introduced by Fr\\"olicher and Kriegl, where they were called convenient vector spaces. While much of the structure necessary to demonstrate this observation is already contained in Fr\\"olicher and Kriegl's book, we here give a new interpretation of the category of convenient vector spaces as a model of the differential linear logic of Ehrhard and Regnier. Rather than base our proof on the abstract categorical structure presented by Fr\\"olicher and Kriegl, we prefer to focus on the bornological structure of convenient vector spaces. We believe bornological structures will ultimately yield a wide variety of models of differential logics.

  8. Partial differential equations

    CERN Document Server

    Evans, Lawrence C

    2010-01-01

    This text gives a comprehensive survey of modern techniques in the theoretical study of partial differential equations (PDEs) with particular emphasis on nonlinear equations. The exposition is divided into three parts: representation formulas for solutions; theory for linear partial differential equations; and theory for nonlinear partial differential equations. Included are complete treatments of the method of characteristics; energy methods within Sobolev spaces; regularity for second-order elliptic, parabolic, and hyperbolic equations; maximum principles; the multidimensional calculus of variations; viscosity solutions of Hamilton-Jacobi equations; shock waves and entropy criteria for conservation laws; and, much more.The author summarizes the relevant mathematics required to understand current research in PDEs, especially nonlinear PDEs. While he has reworked and simplified much of the classical theory (particularly the method of characteristics), he primarily emphasizes the modern interplay between funct...

  9. [Differential diagnosis of hoarseness].

    Science.gov (United States)

    Voigt-Zimmermann, S; Lampe, K; Arens, C

    2014-04-01

    Hoarseness can be the leading symptom of dysphonia. In combination with impaired vocal performance and subjective voice-related discomfort, it can represent an individually different handicap for patients and lead to limited participation in social and professional life. Since the reasons for dysphonia may be not only functional but also organic with a potentially poor prognosis, hoarseness must be clarified using differential diagnosis. In addition to the knowledge of possible diseases, pathogenesis, and treatment options for dysphonia, the differential diagnostic approach requires profound knowledge of the various diagnostic methods, and of the interpretation of the results in particular. The etiology of dysphonia is very diverse and rarely monocausal. Therefore, a team-based and interdisciplinary differential diagnostic approach is recommended.

  10. Advanced differential quadrature methods

    CERN Document Server

    Zong, Zhi

    2009-01-01

    Modern Tools to Perform Numerical DifferentiationThe original direct differential quadrature (DQ) method has been known to fail for problems with strong nonlinearity and material discontinuity as well as for problems involving singularity, irregularity, and multiple scales. But now researchers in applied mathematics, computational mechanics, and engineering have developed a range of innovative DQ-based methods to overcome these shortcomings. Advanced Differential Quadrature Methods explores new DQ methods and uses these methods to solve problems beyond the capabilities of the direct DQ method.After a basic introduction to the direct DQ method, the book presents a number of DQ methods, including complex DQ, triangular DQ, multi-scale DQ, variable order DQ, multi-domain DQ, and localized DQ. It also provides a mathematical compendium that summarizes Gauss elimination, the Runge-Kutta method, complex analysis, and more. The final chapter contains three codes written in the FORTRAN language, enabling readers to q...

  11. Overshooting by differential heating

    CERN Document Server

    Andrássy, R

    2015-01-01

    On the long nuclear time scale of stellar main-sequence evolution, even weak mixing processes can become relevant for redistributing chemical species in a star. We investigate a process of "differential heating," which occurs when a temperature fluctuation propagates by radiative diffusion from the boundary of a convection zone into the adjacent radiative zone. The resulting perturbation of the hydrostatic equilibrium causes a flow that extends some distance from the convection zone. We study a simplified differential-heating problem with a static temperature fluctuation imposed on a solid boundary. The astrophysically relevant limit of a high Reynolds number and a low P\\'eclet number (high thermal diffusivity) turns out to be interestingly non-intuitive. We derive a set of scaling relations for the stationary differential heating flow. A numerical method adapted to a high dynamic range in flow amplitude needed to detect weak flows is presented. Our two-dimensional simulations show that the flow reaches a sta...

  12. Fractional Differential Equations

    Directory of Open Access Journals (Sweden)

    Jianping Zhao

    2012-01-01

    Full Text Available An extended fractional subequation method is proposed for solving fractional differential equations by introducing a new general ansätz and Bäcklund transformation of the fractional Riccati equation with known solutions. Being concise and straightforward, this method is applied to the space-time fractional coupled Burgers’ equations and coupled MKdV equations. As a result, many exact solutions are obtained. It is shown that the considered method provides a very effective, convenient, and powerful mathematical tool for solving fractional differential equations.

  13. Digital Differential Geometry Processing

    Institute of Scientific and Technical Information of China (English)

    Xin-Guo Liu; Hu-Jun Bao; Qun-Sheng Peng

    2006-01-01

    The theory and methods of digital geometry processing has been a hot research area in computer graphics, as geometric models serves as the core data for 3D graphics applications. The purpose of this paper is to introduce some recent advances in digital geometry processing, particularly mesh fairing, surface parameterization and mesh editing, that heavily use differential geometry quantities. Some related concepts from differential geometry, such as normal, curvature, gradient,Laplacian and their counterparts on digital geometry are also reviewed for understanding the strength and weakness of various digital geometry processing methods.

  14. Numerical differential protection

    CERN Document Server

    Ziegler, Gerhard

    2012-01-01

    Differential protection is a fast and selective method of protection against short-circuits. It is applied in many variants for electrical machines, trans?formers, busbars, and electric lines.Initially this book covers the theory and fundamentals of analog and numerical differential protection. Current transformers are treated in detail including transient behaviour, impact on protection performance, and practical dimensioning. An extended chapter is dedicated to signal transmission for line protection, in particular, modern digital communication and GPS timing.The emphasis is then pla

  15. Cross-differential amplifier

    Science.gov (United States)

    Hajimiri, Seyed-Ali (Inventor); Kee, Scott D. (Inventor); Aoki, Ichiro (Inventor)

    2013-01-01

    A cross-differential amplifier is provided. The cross-differential amplifier includes an inductor connected to a direct current power source at a first terminal. A first and second switch, such as transistors, are connected to the inductor at a second terminal. A first and second amplifier are connected at their supply terminals to the first and second switch. The first and second switches are operated to commutate the inductor between the amplifiers so as to provide an amplified signal while limiting the ripple voltage on the inductor and thus limiting the maximum voltage imposed across the amplifiers and switches.

  16. Stochastic differential equations and applications

    CERN Document Server

    Friedman, Avner

    2006-01-01

    This text develops the theory of systems of stochastic differential equations, and it presents applications in probability, partial differential equations, and stochastic control problems. Originally published in two volumes, it combines a book of basic theory and selected topics with a book of applications.The first part explores Markov processes and Brownian motion; the stochastic integral and stochastic differential equations; elliptic and parabolic partial differential equations and their relations to stochastic differential equations; the Cameron-Martin-Girsanov theorem; and asymptotic es

  17. Mathematical analysis differentiation and integration

    CERN Document Server

    Aramanovich, IG; Lyusternik, LA; Sneddon, I N

    1965-01-01

    Mathematical Analysis: Differentiation and Integration is devoted to two basic operations of mathematical analysis, differentiation and integration. The problems directly connected with the operations of differentiation and integration of functions of one or several variables are discussed, together with elementary generalizations of these operations. This volume is comprised of seven chapters and begins by considering the differentiation of functions of one variable and of n variables, paying particular attention to derivatives and differentials as well as their properties. The next chapter d

  18. Differential Equations with Linear Algebra

    CERN Document Server

    Boelkins, Matthew R; Potter, Merle C

    2009-01-01

    Linearity plays a critical role in the study of elementary differential equations; linear differential equations, especially systems thereof, demonstrate a fundamental application of linear algebra. In Differential Equations with Linear Algebra, we explore this interplay between linear algebra and differential equations and examine introductory and important ideas in each, usually through the lens of important problems that involve differential equations. Written at a sophomore level, the text is accessible to students who have completed multivariable calculus. With a systems-first approach, t

  19. Hepatocyte differentiation of mesenchymalstemcells

    Institute of Scientific and Technical Information of China (English)

    Xu-Bo Wu; Ran Tao

    2012-01-01

    BACKGROUND: Liver cell transplantation and bioartiifcial liver may provide metabolic support of liver function temporary and are prospective treatments for patients with liver failure. Mesenchymal stem cells (MSCs) are expected to be an ideal cell source for transplantation or liver tissue engineering, however the hepatic differentiation of MSCs is still insufifcient for clinical application. DATA  SOURCES: A PubMed search on "mesenchymal stem cells","liver cell"and"hepatocyte differentiation"was performed on the topic, and the relevant articles published in the past ten years were reviewed. RESULTS:Hepatocyte-like cells differentiated from MSCs are a promising cell source for liver regeneration or tissue engineering. Although it is still a matter of debate as to whether MSC-derived hepatocytes may efifciently repopulate a host liver to provide adequate functional substitution, the majority of animal studies support that MSCs can become key players in liver-directed regenerative medicine. However the clinical application of human stem cells in the treatment of liver diseases is still in its infancy. CONCLUSIONS: Future studies are required to improve the efifcacy and consistency of hepatic differentiation from MSCs. It is necessary to better understand the mechanism to achieve transdifferentiation with high efifciency. More clinical trials are warranted to prove their efifcacy in the management of patients with liver failure.

  20. Investigating typographic differentiation

    DEFF Research Database (Denmark)

    Beier, Sofie; Dyson, Mary

    2016-01-01

    Text designers are likely to benefit from guidance on how to use typographic differentiation for emphasis. Three experiments use purposely-designed fonts to explore the size and nature of differences in the stylistic characteristics of fonts (weight, width, contrast, italic) which affect letter...

  1. Ghrelin and cell differentiation

    Institute of Scientific and Technical Information of China (English)

    Geyang Xu; Yin Li; Wenjiao An; Weizhen Zhang

    2008-01-01

    Ghrelin, an endogenous ligand for the growth hormone secretagogue receptor, is a gastric hormone that has been found to have a wide variety of biological functions. This review summarizes our current understanding of the effects of ghrelin on cell differentiation and tissue development, with an emphasis on the lineage determination of mesenchymal stem cells.

  2. Klasseledelse, inklusion og differentiering

    DEFF Research Database (Denmark)

    Jørgensen, Christina; Mottelson, Martha

    2014-01-01

    Kapitlet behandler forholdet mellem de tre begreber klasseledelse, inklusion og differentiering og ser på, hvordan de folder sig ud i folkeskolens praksis. Der tages afsæt i en definition af klasseledelse som alle de redskaber, læreren tager i anvendelse med henblik på at få timen til tage form på...

  3. [Cluster headache differential diagnosis].

    Science.gov (United States)

    Guégan-Massardier, Evelyne; Laubier, Cécile

    2015-11-01

    Cluster headache is characterized by disabling stereotyped headache. Early diagnosis allows appropriate treatment, unfortunately diagnostic errors are frequent. The main differential diagnoses are other primary or essential headaches. Migraine, more frequent and whose diagnosis is carried by excess, trigeminal neuralgia or other trigemino-autonomic cephalgia. Vascular or tumoral underlying condition can mimic cluster headache, neck and brain imaging is recommended, ideally MRI.

  4. Parametric Differentiation and Integration

    Science.gov (United States)

    Chen, Hongwei

    2009-01-01

    Parametric differentiation and integration under the integral sign constitutes a powerful technique for calculating integrals. However, this topic is generally not included in the undergraduate mathematics curriculum. In this note, we give a comprehensive review of this approach, and show how it can be systematically used to evaluate most of the…

  5. Invariant differential operators

    CERN Document Server

    Dobrev, Vladimir K

    2016-01-01

    With applications in quantum field theory, elementary particle physics and general relativity, this two-volume work studies invariance of differential operators under Lie algebras, quantum groups, superalgebras including infinite-dimensional cases, Schrödinger algebras, applications to holography. This first volume covers the general aspects of Lie algebras and group theory.

  6. 454 Transcriptome sequencing suggests a role for two-component signalling in cellularization and differentiation of barley endosperm transfer cells.

    Directory of Open Access Journals (Sweden)

    Johannes Thiel

    Full Text Available BACKGROUND: Cell specification and differentiation in the endosperm of cereals starts at the maternal-filial boundary and generates the endosperm transfer cells (ETCs. Besides the importance in assimilate transfer, ETCs are proposed to play an essential role in the regulation of endosperm differentiation by affecting development of proximate endosperm tissues. We attempted to identify signalling elements involved in early endosperm differentiation by using a combination of laser-assisted microdissection and 454 transcriptome sequencing. PRINCIPAL FINDINGS: 454 sequencing of the differentiating ETC region from the syncytial state until functionality in transfer processes captured a high proportion of novel transcripts which are not available in existing barley EST databases. Intriguingly, the ETC-transcriptome showed a high abundance of elements of the two-component signalling (TCS system suggesting an outstanding role in ETC differentiation. All components and subfamilies of the TCS, including distinct kinds of membrane-bound receptors, have been identified to be expressed in ETCs. The TCS system represents an ancient signal transduction system firstly discovered in bacteria and has previously been shown to be co-opted by eukaryotes, like fungi and plants, whereas in animals and humans this signalling route does not exist. Transcript profiling of TCS elements by qRT-PCR suggested pivotal roles for specific phosphorelays activated in a coordinated time flow during ETC cellularization and differentiation. ETC-specificity of transcriptionally activated TCS phosphorelays was assessed for early differentiation and cellularization contrasting to an extension of expression to other grain tissues at the beginning of ETC maturation. Features of candidate genes of distinct phosphorelays and transcriptional activation of genes putatively implicated in hormone signalling pathways hint at a crosstalk of hormonal influences, putatively ABA and ethylene, and

  7. Checklist of Chinese Ants :Formicomorph Subfamilies (Hymenoptera : Formicidae) (Ⅱ)%中国蚁科昆虫名录——蚁型亚科群(膜翅目:蚁科)(Ⅱ)

    Institute of Scientific and Technical Information of China (English)

    冉浩; 周善义

    2012-01-01

    本文总结中国蚁型亚科群(the formicomorph subfamilies)蚁亚科Formieinae已知昆虫10属107种4亚种,其中箭蚁属Cataglyphis 7种,蚁属Formica 44种1亚种,短角蚁属Gesomyrmex 1种,毛蚁属Lasius 19种,刺结蚁属Lepisiota 8种3亚种,长齿蚁属Myrmoteras 2种,尼氏蚁属Nylanderia 21种,织叶蚁属Oecophylla 1种,拟立毛蚁属Paraparatrechina 3种,立毛蚁属Paratrechina 1种.因长有德和贺达汉于2002年命名的粗壮黑蚁的Formica robusta已被Carpenter占用,故将其重命名为长贺氏蚁Formica changhei Ran et Zhou.根据Lapolla最新研究成果,将观音立毛蚁和孔明立毛蚁从立毛蚁属Paratrechina中移至拟立毛蚁属Paraparatrechina,提出了2个新组合,即:观音拟立毛蚁Paraparatrechina guanyin (Terayama,2009)com.nov.和孔明拟立毛蚁Paraparatrechina kongming (Terayama,2009) com.nov..文中给出各种的中文译名、拉丁学名和分布,并对近年来分类地位发生变化、具有较大经济意义和社会意义的种,以及需要特别说明的种作了注解.%107 known species, 4 subspcies belonging to 10 genera of the subfamily Formicinae of the formicomorph subfamilies from China are listed. Among them Cataglyphis with 7 species, Formica with 44 species and 1 subspecies,Gesomyrmex with 1 species,Lasius with 19 species,Lepisiota with 8 species and 3 subspecies,Myrmoteras with 2 species,Nylanderia with 21 species,Oecophylla with 1 species,Para-paratrechina with 3 species,and Paratrechina with 1 species. Formica robusta Chang et He,2002 was renamed as Formica changhei Ran et Zhou as the former was occupied by Formica robusta Carpenter. According to the results of Lapolla et al. ,removed guanyin and kongming from the genus Paratrechina to the genus Paraparatrechina, and combinated two species, i. e. Paraparatrechina guanyin (Terayama, 2009),com. nov. and Paraparatrechina kongming (Terayama,2009) ,com. nov.. All species were treated with Chinese translated names and latin names

  8. Pseudo-differentiation syndrome

    Directory of Open Access Journals (Sweden)

    Dina Khalaf

    2011-12-01

    Full Text Available A patient with relapsed acute myeloid leukemia (AML (M2 FAB classification developed a differentiating syndrome upon receiving Decitabine therapy given with palliative intent. The patient presented with high grade fever, constitutional symptoms and severe chest symptoms with no underlying lung condition. Chest x-ray (CXR showed diffuse pulmonary infiltrates. Septic work up followed by intravenous broad spectrum antimicrobials did not improve his condition. Pan cultures’ results were repeatedly negative. Treatment with high dose Dexamethasone (DXM resulted in marked clinical and radiological improvement. Our patient initially presented with relapsed AML (M2 Fab classification with t (8; 21; negative FMS-like tyrosine kinase -internal tandem duplication (FLT3-ITD which are all good prognostic factors, yet the patient had an atypical clinical course with early frequent relapses, differentiation syndrome associated with Decitabine therapy and late in his disease, he developed a granulocytic sarcoma.

  9. Renormalizing Partial Differential Equations

    OpenAIRE

    Bricmont, J.; Kupiainen, A.

    1994-01-01

    In this review paper, we explain how to apply Renormalization Group ideas to the analysis of the long-time asymptotics of solutions of partial differential equations. We illustrate the method on several examples of nonlinear parabolic equations. We discuss many applications, including the stability of profiles and fronts in the Ginzburg-Landau equation, anomalous scaling laws in reaction-diffusion equations, and the shape of a solution near a blow-up point.

  10. Arithmetic partial differential equations

    OpenAIRE

    Buium, Alexandru; Simanca, Santiago R.

    2006-01-01

    We develop an arithmetic analogue of linear partial differential equations in two independent ``space-time'' variables. The spatial derivative is a Fermat quotient operator, while the time derivative is the usual derivation. This allows us to ``flow'' integers or, more generally, points on algebraic groups with coordinates in rings with arithmetic flavor. In particular, we show that elliptic curves have certain canonical ``flows'' on them that are the arithmetic analogues of the heat and wave...

  11. Differentiation in Classroom Practice

    DEFF Research Database (Denmark)

    Mottelson, Martha

    2015-01-01

    Differentiation in School Practice is an ongoing research project currently being carried out in UCC’s research department by myself and my coworker Christina Jørgensen. The project includes a field study of everyday life in a Danish 5th grade classroom with the aim to observe, describe and analy...... those everyday practices in the classroom that ultimately result in offering students different positions, identities and opportunities for participation....

  12. Differential equations with Mathematica

    CERN Document Server

    Abell, Martha L

    2004-01-01

    The Third Edition of the Differential Equations with Mathematica integrates new applications from a variety of fields,especially biology, physics, and engineering. The new handbook is also completely compatible with recent versions of Mathematica and is a perfect introduction for Mathematica beginners.* Focuses on the most often used features of Mathematica for the beginning Mathematica user* New applications from a variety of fields, including engineering, biology, and physics* All applications were completed using recent versions of Mathematica

  13. Supremum norm differentiability

    Directory of Open Access Journals (Sweden)

    I. E. Leonard

    1983-01-01

    Full Text Available The points of Gateaux and Fréchet differentiability of the norm in C(T,E are obtained, where T is a locally compact Hausdorff space and E is a real Banach space. Applications of these results are given to the space ℓ∞(E of all bounded sequences in E and to the space B(ℓ1,E of all bounded linear operators from ℓ1 into E

  14. Differential equations I essentials

    CERN Document Server

    REA, Editors of

    2012-01-01

    REA's Essentials provide quick and easy access to critical information in a variety of different fields, ranging from the most basic to the most advanced. As its name implies, these concise, comprehensive study guides summarize the essentials of the field covered. Essentials are helpful when preparing for exams, doing homework and will remain a lasting reference source for students, teachers, and professionals. Differential Equations I covers first- and second-order equations, series solutions, higher-order linear equations, and the Laplace transform.

  15. Is Titan Partially Differentiated?

    Science.gov (United States)

    Mitri, G.; Pappalardo, R. T.; Stevenson, D. J.

    2009-12-01

    The recent measurement of the gravity coefficients from the Radio Doppler data of the Cassini spacecraft has improved our knowledge of the interior structure of Titan (Rappaport et al. 2008 AGU, P21A-1343). The measured gravity field of Titan is dominated by near hydrostatic quadrupole components. We have used the measured gravitational coefficients, thermal models and the hydrostatic equilibrium theory to derive Titan's interior structure. The axial moment of inertia gives us an indication of the degree of the interior differentiation. The inferred axial moment of inertia, calculated using the quadrupole gravitational coefficients and the Radau-Darwin approximation, indicates that Titan is partially differentiated. If Titan is partially differentiated then the interior must avoid melting of the ice during its evolution. This suggests a relatively late formation of Titan to avoid the presence of short-lived radioisotopes (Al-26). This also suggests the onset of convection after accretion to efficiently remove the heat from the interior. The outer layer is likely composed mainly of water in solid phase. Thermal modeling indicates that water could be present also in liquid phase forming a subsurface ocean between an outer ice I shell and a high pressure ice layer. Acknowledgments: This work was conducted at the Jet Propulsion Laboratory, California Institute of Technology, under contract with the National Aeronautics and Space Administration.

  16. Differentially Private Distributed Sensing

    Energy Technology Data Exchange (ETDEWEB)

    Fink, Glenn A.

    2016-12-11

    The growth of the Internet of Things (IoT) creates the possibility of decentralized systems of sensing and actuation, potentially on a global scale. IoT devices connected to cloud networks can offer Sensing and Actuation as a Service (SAaaS) enabling networks of sensors to grow to a global scale. But extremely large sensor networks can violate privacy, especially in the case where IoT devices are mobile and connected directly to the behaviors of people. The thesis of this paper is that by adapting differential privacy (adding statistically appropriate noise to query results) to groups of geographically distributed sensors privacy could be maintained without ever sending all values up to a central curator and without compromising the overall accuracy of the data collected. This paper outlines such a scheme and performs an analysis of differential privacy techniques adapted to edge computing in a simulated sensor network where ground truth is known. The positive and negative outcomes of employing differential privacy in distributed networks of devices are discussed and a brief research agenda is presented.

  17. Conservation laws, differential identities, and constraints of partial differential equations

    Science.gov (United States)

    Zharinov, V. V.

    2015-11-01

    We consider specific cohomological properties such as low-dimensional conservation laws and differential identities of systems of partial differential equations (PDEs). We show that such properties are inherent to complex systems such as evolution systems with constraints. The mathematical tools used here are the algebraic analysis of PDEs and cohomologies over differential algebras and modules.

  18. Nth-order Fuzzy Differential Equations Under Generalized Differentiability

    Directory of Open Access Journals (Sweden)

    Soheil Salahshour

    2011-11-01

    Full Text Available In this paper, the multiple solutions of Nth-order fuzzy differential equations by the equivalent integral forms are considered. Also, an Existence and uniqueness theorem of solution of Nth-order fuzzy differential equations is proved under Nth-order generalized differentiability in Banach space.

  19. Differential transimpedance amplifier circuit for correlated differential amplification

    Science.gov (United States)

    Gresham, Christopher A.; Denton, M. Bonner; Sperline, Roger P.

    2008-07-22

    A differential transimpedance amplifier circuit for correlated differential amplification. The amplifier circuit increase electronic signal-to-noise ratios in charge detection circuits designed for the detection of very small quantities of electrical charge and/or very weak electromagnetic waves. A differential, integrating capacitive transimpedance amplifier integrated circuit comprising capacitor feedback loops performs time-correlated subtraction of noise.

  20. Differential invariants of second-order ordinary differential equations

    OpenAIRE

    Rosado Maria, Maria Eugenia

    2011-01-01

    The notion of a differential invariant for systems of second-order differential equations on a manifold M with respect to the group of vertical automorphisms of the projection is de?ned and the Chern connection attached to a SODE allows one to determine a basis for second-order differential invariants of a SODE.

  1. Putting Differentials Back into Calculus

    Science.gov (United States)

    Dray, Tevian; Manogue, Corrine A.

    2010-01-01

    We argue that the use of differentials in introductory calculus courses is useful and provides a unifying theme, leading to a coherent view of the calculus. Along the way, we meet several interpretations of differentials, some better than others.

  2. Group valued differential forms revisited

    DEFF Research Database (Denmark)

    Kock, Anders

    We study the relationship between combinatorial group valued differential forms, and classical differential forms with values in the corresponding Lie algebra. In particular, we compare simplicial coboundary and exterior derivative for 1-forms. The results represent strengthenings of results...

  3. Differential expression profiles in the midgut of Triatoma infestans infected with Trypanosoma cruzi.

    Directory of Open Access Journals (Sweden)

    Diego S Buarque

    Full Text Available Chagas disease, or American trypanosomiasis, is a parasitic disease caused by the protozoan Trypanosoma cruzi and is transmitted by insects from the Triatominae subfamily. To identify components involved in the protozoan-vector relationship, we constructed and analyzed cDNA libraries from RNA isolated from the midguts of uninfected and T. cruzi-infected Triatoma infestans, which are major vectors of Chagas disease. We generated approximately 440 high-quality Expressed Sequence Tags (ESTs from each T. infestans midgut cDNA library. The sequences were grouped in 380 clusters, representing an average length of 664.78 base pairs (bp. Many clusters were not classified functionally, representing unknown transcripts. Several transcripts involved in different processes (e.g., detoxification showed differential expression in response to T. cruzi infection. Lysozyme, cathepsin D, a nitrophorin-like protein and a putative 14 kDa protein were significantly upregulated upon infection, whereas thioredoxin reductase was downregulated. In addition, we identified several transcripts related to metabolic processes or immunity with unchanged expressions, including infestin, lipocalins and defensins. We also detected ESTs encoding juvenile hormone binding protein (JHBP, which seems to be involved in insect development and could be a target in control strategies for the vector. This work demonstrates differential gene expression upon T. cruzi infection in the midgut of T. infestans. These data expand the current knowledge regarding vector-parasite interactions for Chagas disease.

  4. Tasting Arterial Blood: What do the Carotid Chemoreceptors Sense?

    Directory of Open Access Journals (Sweden)

    Nanduri R. Prabakhar

    2015-01-01

    Full Text Available The carotid bodies are sensory organs that detect the chemical composition of the arterial blood. The carotid body sensory activity increases in response to arterial hypoxemia and the ensuing chemoreflex regulates vital homeostatic functions. Recent studies suggest that the carotid bodies might also sense arterial blood glucose and circulating insulin levels. This review focuses on how the carotid bodies sense O2, glucose and insulin and some potential implications of these sensory functions on physiological regulation and in pathophysiological conditions. Emerging evidence suggests that carbon monoxide (CO-regulated hydrogen sulfide (H2S, stemming from hypoxia, depolarizes type I cells by inhibiting certain K+ channels, facilitates voltage-gated Ca2+ influx leading to sensory excitation of the carotid body. Elevated CO and decreased H2S renders the carotid bodies insensitive to hypoxia resulting in attenuated ventilatory adaptations to high altitude hypoxia, whereas reduced CO and high H2S result in hypersensitivity of the carotid bodies to hypoxia and hypertension. Acute hypoglycemia augments the carotid body responses to hypoxia but that a prolonged lack of glucose in the carotid bodies can lead to a failure to sense hypoxia. Emerging evidence also indicates that carotid bodies might sense insulin directly independent of its effect on glucose, linking the carotid bodies to the pathophysiological consequences of the metabolic syndrome. How glucose and insulin interact with the CO-H2S signalling is an area of ongoing study.KEY WORDS: Glomus cells, K+ channels, Carbon monoxide, hydrogen sulfide, hypoglycemia, diabetes.

  5. On Degenerate Partial Differential Equations

    OpenAIRE

    Chen, Gui-Qiang G.

    2010-01-01

    Some of recent developments, including recent results, ideas, techniques, and approaches, in the study of degenerate partial differential equations are surveyed and analyzed. Several examples of nonlinear degenerate, even mixed, partial differential equations, are presented, which arise naturally in some longstanding, fundamental problems in fluid mechanics and differential geometry. The solution to these fundamental problems greatly requires a deep understanding of nonlinear degenerate parti...

  6. Differential operator multiplication method for fractional differential equations

    Science.gov (United States)

    Tang, Shaoqiang; Ying, Yuping; Lian, Yanping; Lin, Stephen; Yang, Yibo; Wagner, Gregory J.; Liu, Wing Kam

    2016-08-01

    Fractional derivatives play a very important role in modeling physical phenomena involving long-range correlation effects. However, they raise challenges of computational cost and memory storage requirements when solved using current well developed numerical methods. In this paper, the differential operator multiplication method is proposed to address the issues by considering a reaction-advection-diffusion equation with a fractional derivative in time. The linear fractional differential equation is transformed into an integer order differential equation by the proposed method, which can fundamentally fix the aforementioned issues for select fractional differential equations. In such a transform, special attention should be paid to the initial conditions for the resulting differential equation of higher integer order. Through numerical experiments, we verify the proposed method for both fractional ordinary differential equations and partial differential equations.

  7. Identification and characterization of CbeI, a novel thermostable restriction enzyme from Caldicellulosiruptor bescii DSM 6725 and a member of a new subfamily of HaeIII-like enzymes.

    Science.gov (United States)

    Chung, Dae-Hwan; Huddleston, Jennifer R; Farkas, Joel; Westpheling, Janet

    2011-11-01

    Potent HaeIII-like DNA restriction activity was detected in cell-free extracts of Caldicellulosiruptor bescii DSM 6725 using plasmid DNA isolated from Escherichia coli as substrate. Incubation of the plasmid DNA in vitro with HaeIII methyltransferase protected it from cleavage by HaeIII nuclease as well as cell-free extracts of C. bescii. The gene encoding the putative restriction enzyme was cloned and expressed in E. coli with a His-tag at the C-terminus. The purified protein was 38 kDa as predicted by the 981-bp nucleic acid sequence, was optimally active at temperatures between 75°C and 85°C, and was stable for more than 1 week when stored at 35°C. The cleavage sequence was determined to be 5'-GG/CC-3', indicating that CbeI is an isoschizomer of HaeIII. A search of the C. bescii genome sequence revealed the presence of both a HaeIII-like restriction endonuclease (Athe 2438) and DNA methyltransferase (Athe 2437). Preliminary analysis of other Caldicellulosiruptor species suggested that this restriction/modification activity is widespread in this genus. A phylogenetic analysis based on sequence alignment and conserved motif searches identified features of CbeI distinct from other members of this group and classified CbeI as a member of a novel subfamily of HaeIII-like enzymes.

  8. 中国细蚁亚科系统分类研究(膜翅目:蚁科)%A Systematic Study on the Ant Subfamily Leptanillinae of China ( Hymenoptera: Formicidae)

    Institute of Scientific and Technical Information of China (English)

    徐正会

    2002-01-01

    Two genera of the ant subfamily Leptanillinae are recorded in China. Three species including a new species of the genus LeptanillaEmery are reported: L. hunaneasis Tang, Li et Chen from Hunan Province, L. taiwanensis Ogata, Terayama et Masuko from Taiwan Province, L. yuananensis sp. nov. from Yunnan Province. Protanilla Taylor is newly recorded in China, of which 2 new species are describedfrom Yunnan Province, i.e.P, concolor sp. nov. and P. bicolor sp. nov. Keys to the two genera of Leptanillinae and their species in Chinabased on worker caste are provided%记载中国细蚁亚科kptanilliBae昆虫2属.报道细蚁属Leptanilla Emery3种:湖南细蚁L. hunanensis Tang, Li et Chen 分布于湖南省,台湾细蚁L. taiwanensis Ogata, Terayama et Masuko分布于台湾省,云南细蚁L. yunnanensis sp. nov.分布于云南省.原细蚁属Protanilla Taylor为中国新记录属,在云南省采集并描述该属2新种:单色原细蚁P. concolor sp. nov.和双色原细蚁P.bicolor sp.nov..编制了细蚁亚科这2属的工蚁分属检索表和中国分布种工蚁分种检索表.

  9. Investigating typographic differentiation

    DEFF Research Database (Denmark)

    Beier, Sofie

    2016-01-01

    Text designers are likely to benefit from guidance on how to use typographic differentiation for emphasis. Three experiments use purposely-designed fonts to explore the size and nature of differences in the stylistic characteristics of fonts (weight, width, contrast, italic) which affect letter...... identification. Results indicate that words set in bold and expanded fonts, when alternated with words set in a Neutral test font, may impair performance, whereas changing to italic does not. Possible explanations are explored through measuring the physical and perceptual similarities of the test fonts...

  10. Partial differential equations

    CERN Document Server

    Friedman, Avner

    2008-01-01

    This three-part treatment of partial differential equations focuses on elliptic and evolution equations. Largely self-contained, it concludes with a series of independent topics directly related to the methods and results of the preceding sections that helps introduce readers to advanced topics for further study. Geared toward graduate and postgraduate students of mathematics, this volume also constitutes a valuable reference for mathematicians and mathematical theorists.Starting with the theory of elliptic equations and the solution of the Dirichlet problem, the text develops the theory of we

  11. Differential diagnosis of tonsillolith

    Directory of Open Access Journals (Sweden)

    Luisa Schertel Cassiano

    2010-07-01

    Full Text Available Introduction:Tonsillolith is a rare type of dystrophic calcification in the palatine tonsils or in the peritonsilar region, which can mimics several intraosseous radiopaque lesions when evaluated by two-dimensional or overlapping images.This may lead to an erroneous diagnosis and to invasive and unnecessary procedures.This study reports a case of tonsillolith that was wrongly diagnosed as an odontoma. Case report: A patient with primary diagnosis of odontoma in the mandibular ramus was referred to surgical treatment of this lesion. Conclusion: Computed tomography (CT scans are fundamentally important to establish differential diagnosis and appropriate treatment for the patient.

  12. Differentiating among penal states.

    Science.gov (United States)

    Lacey, Nicola

    2010-12-01

    This review article assesses Loïc Wacquant's contribution to debates on penality, focusing on his most recent book, Punishing the Poor: The Neoliberal Government of Social Insecurity (Wacquant 2009), while setting its argument in the context of his earlier Prisons of Poverty (1999). In particular, it draws on both historical and comparative methods to question whether Wacquant's conception of 'the penal state' is adequately differentiated for the purposes of building the explanatory account he proposes; about whether 'neo-liberalism' has, materially, the global influence which he ascribes to it; and about whether, therefore, the process of penal Americanization which he asserts in his recent writings is credible.

  13. Differentiation in online retailing

    DEFF Research Database (Denmark)

    Kellner, Julian; Wagner, Gerhard; Zielke, Stephan;

    Due to the highly competitive nature of the online retail environment, differentiation strategies are of importance for online retailers to gain competitive advantages and to achieve a unique positioning in the market. However, little is known about perceptual dimensions used by consumers to make...... a distinction between online retailers. The present study addresses this research gap by using a repertory grid approach to identify points of difference between online retailers from a consumer’s perspective. The results have important implications for positioning strategies of online retailers and research...... on online store formats....

  14. Ordinary differential equations

    CERN Document Server

    Cox, William

    1995-01-01

    Building on introductory calculus courses, this text provides a sound foundation in the underlying principles of ordinary differential equations. Important concepts, including uniqueness and existence theorems, are worked through in detail and the student is encouraged to develop much of the routine material themselves, thus helping to ensure a solid understanding of the fundamentals required.The wide use of exercises, problems and self-assessment questions helps to promote a deeper understanding of the material and it is developed in such a way that it lays the groundwork for further

  15. Boolean differential equations

    CERN Document Server

    Steinbach, Bernd

    2013-01-01

    The Boolean Differential Calculus (BDC) is a very powerful theory that extends the structure of a Boolean Algebra significantly. Based on a small number of definitions, many theorems have been proven. The available operations have been efficiently implemented in several software packages. There is a very wide field of applications. While a Boolean Algebra is focused on values of logic functions, the BDC allows the evaluation of changes of function values. Such changes can be explored for pairs of function values as well as for whole subspaces. Due to the same basic data structures, the BDC can

  16. Partial differential equations

    CERN Document Server

    Sloan, D; Süli, E

    2001-01-01

    /homepage/sac/cam/na2000/index.html7-Volume Set now available at special set price ! Over the second half of the 20th century the subject area loosely referred to as numerical analysis of partial differential equations (PDEs) has undergone unprecedented development. At its practical end, the vigorous growth and steady diversification of the field were stimulated by the demand for accurate and reliable tools for computational modelling in physical sciences and engineering, and by the rapid development of computer hardware and architecture. At the more theoretical end, the analytical insight in

  17. Differential diagnosis of hyponatraemia.

    LENUS (Irish Health Repository)

    Thompson, Chris

    2012-03-01

    The appropriate management of hyponatraemia is reliant on the accurate identification of the underlying cause of the hyponatraemia. In the light of evidence which has shown that the use of a clinical algorithm appears to improve accuracy in the differential diagnosis of hyponatraemia, the European Hyponatraemia Network considered the use of two algorithms. One was developed from a nephrologist\\'s view of hyponatraemia, while the other reflected the approach of an endocrinologist. Both of these algorithms concurred on the importance of assessing effective blood volume status and the measurement of urine sodium concentration in the diagnostic process. To demonstrate the importance of accurate diagnosis to the correct treatment of hyponatraemia, special consideration was given to hyponatraemia in neurosurgical patients. The differentiation between the syndrome of inappropriate antidiuretic hormone secretion (SIADH), acute adrenocorticotropic hormone (ACTH) deficiency, fluid overload and cerebral salt-wasting syndrome was discussed. In patients with SIADH, fluid restriction has been the mainstay of treatment despite the absence of an evidence base for its use. An approach to using fluid restriction to raise serum tonicity in patients with SIADH and to identify patients who are likely to be recalcitrant to fluid restriction was also suggested.

  18. Abnormalities of gonadal differentiation.

    Science.gov (United States)

    Berkovitz, G D; Seeherunvong, T

    1998-04-01

    Gonadal differentiation involves a complex interplay of developmental pathways. The sex determining region Y (SRY) gene plays a key role in testis determination, but its interaction with other genes is less well understood. Abnormalities of gonadal differentiation result in a range of clinical problems. 46,XY complete gonadal dysgenesis is defined by an absence of testis determination. Subjects have female external genitalia and come to clinical attention because of delayed puberty. Individuals with 46,XY partial gonadal dysgenesis usually present in the newborn period for the valuation of ambiguous genitalia. Gonadal histology always shows an abnormality of seminiferous tubule formation. A diagnosis of 46,XY true hermaphroditism is made if the gonads contain well-formed testicular and ovarian elements. Despite the pivotal role of the SRY gene in testis development, mutations of SRY are unusual in subjects with a 46,XY karyotype and abnormal gonadal development. 46,XX maleness is defined by testis determination in an individual with a 46,XX karyotype. Most affected individuals have a phenotype similar to that of Klinefelter syndrome. In contrast, subjects with 46,XX true hermaphroditism usually present with ambiguous genitalia. The majority of subjects with 46,XX maleness have Y sequences including SRY in genomic DNA. However, only rare subjects with 46,XX true hermaphroditism have translocated sequences encoding SRY. Mosaicism and chimaerism involving the Y chromosome can also be associated with abnormal gonadal development. However, the vast majority of subjects with 45,X/46,XY mosaicism have normal testes and normal male external genitalia.

  19. Differential diagnosis diphtheria adults

    Directory of Open Access Journals (Sweden)

    Yu. I. Liashenko

    2010-01-01

    Full Text Available A total of 1,824 human cases of diphtheria, treated at the Clinical Infectious Diseases Hospital SP Botkin (St. Petersburg during 1993, as well as 19 deaths in 1994. It is known that early diagnosis of infectious diseases, especially diphtheria, contributes to the favorable outcome of the disease. The diagnosis of diphtheria at the prehospital stage is always difficult. Presented in detail the differential diagnosis of the disease, clinically similar to diphtheria: Lacunal angina, angina Simanovsky, infectious mononucleosis, angina Ludwig’s angina Dugue, syphilis, non-infectious with clinical «masks» of diphtheria and other. Diphtheria epidemic of 1993–1994 in Russia and, in particular, in St. Petersburg, showed that the late admission of patients with diphtheria infection in hospitals, usually associated with irregular differential diagnosis of this dangerous disease.

  20. Koszul differential graded modules

    Institute of Scientific and Technical Information of China (English)

    HE JiWei; WU QuanShui

    2009-01-01

    The concept of Koszulity for differential graded (DG, for short) modules is introduced. It is shown that any bounded below DG module with bounded Ext-group to the trivial module over a Koszul DG algebra has a Koszul DG submodule (up to a shift and truncation), moreover such a DG module can be approximated by Koszul DG modules (Theorem 3.6). Let A be a Koszul DG algebra, and Dc (A) be the full triangulated subcategory of the derived category of DG A-modules generated by the object AA. If the trivial DG module kA lies in Dc(A), then the heart of the standard t-structure on Dc(A) is anti-equivalent to the category of finitely generated modules over some finite dimensional algebra. As a corollary, Dc(A) is equivalent to the bounded derived category of its heart as triangulated categories.

  1. Koszul differential graded modules

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    The concept of Koszulity for differential graded (DG, for short) modules is introduced. It is shown that any bounded below DG module with bounded Ext-group to the trivial module over a Koszul DG algebra has a Koszul DG submodule (up to a shift and truncation), moreover such a DG module can be approximated by Koszul DG modules (Theorem 3.6). Let A be a Koszul DG algebra, and Dc(A) be the full triangulated subcategory of the derived category of DG A-modules generated by the object AA. If the trivial DG module kA lies in Dc(A), then the heart of the standard t-structure on Dc(A) is anti-equivalent to the category of finitely generated modules over some finite dimensional algebra. As a corollary, Dc(A) is equivalent to the bounded derived category of its heart as triangulated categories.

  2. Scaling of differential equations

    CERN Document Server

    Langtangen, Hans Petter

    2016-01-01

    The book serves both as a reference for various scaled models with corresponding dimensionless numbers, and as a resource for learning the art of scaling. A special feature of the book is the emphasis on how to create software for scaled models, based on existing software for unscaled models. Scaling (or non-dimensionalization) is a mathematical technique that greatly simplifies the setting of input parameters in numerical simulations. Moreover, scaling enhances the understanding of how different physical processes interact in a differential equation model. Compared to the existing literature, where the topic of scaling is frequently encountered, but very often in only a brief and shallow setting, the present book gives much more thorough explanations of how to reason about finding the right scales. This process is highly problem dependent, and therefore the book features a lot of worked examples, from very simple ODEs to systems of PDEs, especially from fluid mechanics. The text is easily accessible and exam...

  3. Applied partial differential equations

    CERN Document Server

    Logan, J David

    2004-01-01

    This primer on elementary partial differential equations presents the standard material usually covered in a one-semester, undergraduate course on boundary value problems and PDEs. What makes this book unique is that it is a brief treatment, yet it covers all the major ideas: the wave equation, the diffusion equation, the Laplace equation, and the advection equation on bounded and unbounded domains. Methods include eigenfunction expansions, integral transforms, and characteristics. Mathematical ideas are motivated from physical problems, and the exposition is presented in a concise style accessible to science and engineering students; emphasis is on motivation, concepts, methods, and interpretation, rather than formal theory. This second edition contains new and additional exercises, and it includes a new chapter on the applications of PDEs to biology: age structured models, pattern formation; epidemic wave fronts, and advection-diffusion processes. The student who reads through this book and solves many of t...

  4. Differential and holomorphic differential operators on noncommutative algebras

    Science.gov (United States)

    Beggs, E.

    2015-07-01

    This paper deals with sheaves of differential operators on noncommutative algebras, in a manner related to the classical theory of D-modules. The sheaves are defined by quotienting the tensor algebra of vector fields (suitably deformed by a covariant derivative). As an example we can obtain enveloping algebra like relations for Hopf algebras with differential structures which are not bicovariant. Symbols of differential operators are defined, but not studied. These sheaves are shown to be in the center of a category of bimodules with flat bimodule covariant derivatives. Also holomorphic differential operators are considered.

  5. DNA microarray analysis of genes differentially expressed in adipocyte differentiation

    Indian Academy of Sciences (India)

    Chunyan Yin; Yanfeng Xiao; Wei Zhang; Erdi Xu; Weihua Liu; Xiaoqing Yi; Ming Chang

    2014-06-01

    In the present study, the human liposarcoma cell line SW872 was used to identify global changes in gene expression profiles occurring during adipogenesis. We further explored some of the genes expressed during the late phase of adipocyte differentiation. These genes may play a major role in promoting excessive proliferation and accumulation of lipid droplets, which contribute to the development of obesity. By using microarray-based technology, we examined differential gene expression in early differentiated adipocytes and late differentiated adipocytes. Validated genes exhibited a ≥ 10-fold increase in the late phase of adipocyte differentiation by polymerase chain reaction (RT-PCR). Compared with undifferentiated preadipocytes, we found that 763 genes were increased in early differentiated adipocytes, and 667 genes were increased in later differentiated adipocytes. Furthermore, 21 genes were found being expressed 10-fold higher in the late phase of adipocyte differentiation. The results were in accordance with the RT-PCR test, which validated 11 genes, namely, CIDEC, PID1, LYRM1, ADD1, PPAR2, ANGPTL4, ADIPOQ, ACOX1, FIP1L1, MAP3K2 and PEX14. Most of these genes were found being expressed in the later phase of adipocyte differentiation involved in obesity-related diseases. The findings may help to better understand the mechanism of obesity and related diseases.

  6. Pseudo-differentiation syndrome

    Directory of Open Access Journals (Sweden)

    Fathi Jehani

    2011-01-01

    Full Text Available

    A patient with relapsed acute myeloid leukemia (AML (M2 FAB classification developed a differentiating syndrome upon receiving Decitabine therapy given with palliative intent. The patient presented with high grade fever, constitutional symptoms and severe chest symptoms with no underlying lung condition. Chest x-ray (CXR showed diffuse pulmonary infiltrates. Septic work up followed by intravenous broad spectrum antimicrobials did not improve his condition. Pan cultures’ results were repeatedly negative. Treatment with high dose Dexamethasone (DXM resulted in marked clinical and radiological improvement.

    Our patient initially presented with relapsed AML (M2 Fab classification with t (8; 21; negative FMS-like tyrosine kinase -internal tandem duplication (FLT3-ITD which are all good prognostic factors, yet the patient had an atypical clinical course with early frequent relapses, differentiation syndrome associated with Decitabine therapy and late in his disease, he developed a granulocytic sarcoma.

  7. An introduction to differential manifolds

    CERN Document Server

    Lafontaine, Jacques

    2015-01-01

    This book is an introduction to differential manifolds. It gives solid preliminaries for more advanced topics: Riemannian manifolds, differential topology, Lie theory. It presupposes little background: the reader is only expected to master basic differential calculus, and a little point-set topology. The book covers the main topics of differential geometry: manifolds, tangent space, vector fields, differential forms, Lie groups, and a few more sophisticated topics such as de Rham cohomology, degree theory and the Gauss-Bonnet theorem for surfaces. Its ambition is to give solid foundations. In particular, the introduction of “abstract” notions such as manifolds or differential forms is motivated via questions and examples from mathematics or theoretical physics. More than 150 exercises, some of them easy and classical, some others more sophisticated, will help the beginner as well as the more expert reader. Solutions are provided for most of them. The book should be of interest to various readers: undergra...

  8. Trypsin potentiates human fibrocyte differentiation.

    Directory of Open Access Journals (Sweden)

    Michael J V White

    Full Text Available Trypsin-containing topical treatments can be used to speed wound healing, although the mechanism of action is unknown. To help form granulation tissue and heal wounds, monocytes leave the circulation, enter the wound tissue, and differentiate into fibroblast-like cells called fibrocytes. We find that 20 to 200 ng/ml trypsin (concentrations similar to those used in wound dressings potentiates the differentiation of human monocytes to fibrocytes in cell culture. Adding trypsin inhibitors increases the amount of trypsin needed to potentiate fibrocyte differentiation, suggesting that the potentiating effect is dependent on trypsin proteolytic activity. Proteases with other site specificities such as pepsin, endoprotease GluC, and chymotrypsin do not potentiate fibrocyte differentiation. This potentiation requires the presence of albumin in the culture medium, and tryptic fragments of human or bovine albumin also potentiate fibrocyte differentiation. These results suggest that topical trypsin speeds wound healing by generating tryptic fragments of albumin, which in turn potentiate fibrocyte differentiation.

  9. Trypsin potentiates human fibrocyte differentiation.

    Science.gov (United States)

    White, Michael J V; Glenn, Melissa; Gomer, Richard H

    2013-01-01

    Trypsin-containing topical treatments can be used to speed wound healing, although the mechanism of action is unknown. To help form granulation tissue and heal wounds, monocytes leave the circulation, enter the wound tissue, and differentiate into fibroblast-like cells called fibrocytes. We find that 20 to 200 ng/ml trypsin (concentrations similar to those used in wound dressings) potentiates the differentiation of human monocytes to fibrocytes in cell culture. Adding trypsin inhibitors increases the amount of trypsin needed to potentiate fibrocyte differentiation, suggesting that the potentiating effect is dependent on trypsin proteolytic activity. Proteases with other site specificities such as pepsin, endoprotease GluC, and chymotrypsin do not potentiate fibrocyte differentiation. This potentiation requires the presence of albumin in the culture medium, and tryptic fragments of human or bovine albumin also potentiate fibrocyte differentiation. These results suggest that topical trypsin speeds wound healing by generating tryptic fragments of albumin, which in turn potentiate fibrocyte differentiation.

  10. 南海分室科单殖吸虫-中国新记录亚科%A NEWLY RECORDED SUBFAMILY OF PSEUDONITZSCHIINAE (MONOGENEA:CAPSALIDAE) IN THE SOUTH CHINA SEA

    Institute of Scientific and Technical Information of China (English)

    杨长平; 邹小梅; 张剑英; 丁雪娟

    2015-01-01

    研究记述寄生于海南清澜绿短臂鱼Aprion virescens鳃上的一种分室科单殖吸虫,短臂鱼蚌盘虫Pseudonitzschia ukuYamaguti,1965。所获标本的形态、量度与Yamaguti(1965)的原始描述基本一致;但南海标本的后吸器上具中央锚钩和边缘小钩等几丁质结构,而 Yamaguti 的描述中无此类结构;原始描述中阴茎表面被向后弯曲的小刺,而南海标本阴茎表面无刺。故此对蚌盘亚科、蚌盘虫属的特征进行了补充修订。该亚科、属及种均为中国新记录。标本保存于华南师范大学生命科学学院鱼类寄生虫学研究室。%A capsalid monogenean,Pseudonitzschia ukuYamaguti,1965, that belongs toPseudonitzschia, Pseudonitzschiinae, was discovered on the gills ofAprion virescens in Qinglan Bay of Hainan in China. The morphology and size of the specimens were consistent with the original description, except that there were anchors and marginal hooklets on their haptor, and that the recurved spines over the cirrus were missing. Therefore here we updated the description of the characteristics of the Pseudonitzschiinae subfamily and thePseudonitzschia genus. The subfamily, genus and species were reported for the first time in China. The specimens were deposited in the Lab of Fish Parasitology of Collage of Life Sciences in the South China Normal University. Amended diagnosis of Pseudonitzschiinae: Capsalidaesensu Yamaguti, 1963. Body elliptical flattened. Haptor disc-shaped, sessile, usually folded antero-posteriorly, armed with one pair of anchors and 14 marginal hooklets; in-dented muscular margin and delicate marginal membrane present; without septa, loculi or papillae. Anterior attachment organ paired, sucker-shaped. One pair of eye spots. Pharynx without constriction. Intestinal limbs with lateral dendritic diverticula, not united posteriorly. Testes numerous, intercecal. Male copulatory pouch muscular, postpharyngeal, con-sisted of ejaculatory and prostatic ducts

  11. Introduction to partial differential equations

    CERN Document Server

    Greenspan, Donald

    2000-01-01

    Designed for use in a one-semester course by seniors and beginning graduate students, this rigorous presentation explores practical methods of solving differential equations, plus the unifying theory underlying the mathematical superstructure. Topics include basic concepts, Fourier series, second-order partial differential equations, wave equation, potential equation, heat equation, approximate solution of partial differential equations, and more. Exercises appear at the ends of most chapters. 1961 edition.

  12. Upregulated Expression of Transient Receptor Potential Cation Channel Subfamily V Receptors in Mucosae of Patients with Oral Squamous Cell Carcinoma and Patients with a History of Alcohol Consumption or Smoking

    Science.gov (United States)

    Sakakibara, Akiko; Sakakibara, Shunsuke; Kusumoto, Junya; Takeda, Daisuke; Hasegawa, Takumi; Akashi, Masaya; Minamikawa, Tsutomu; Hashikawa, Kazunobu; Terashi, Hiroto; Komori, Takahide

    2017-01-01

    Objectives Transient receptor potential cation channel (subfamily V, members 1–4) (TRPV1–4) are expressed in skin and neurons and activated by external stimuli in normal mucosae of all oral cavity sites. The oral cavity is exposed to various stimuli, including temperature, mechanical stimuli, chemical substances, and changes in pH, and, notably, the risk factors for oncogenic transformation in oral squamous epithelium are the same as the external stimuli received by TRPV1–4 receptors. Hence, we examined the relationship between oral squamous cell carcinoma (SCC) and TRPV1–4 expression. Materials and Methods Oral SCC patients (n = 37) who underwent surgical resection were included in this study. We investigated the expression of TRPV1–4 by immunohistochemical staining and quantification of TRPV1–4 mRNA in human oral mucosa. In addition, we compared the TRPV1–4 levels in mucosa from patients with SCC to those in normal oral mucosa. Results The receptors were expressed in oral mucosa at all sites (tongue, buccal mucosa, gingiva, and oral floor) and the expression was stronger in epithelia from patients with SCC than in normal epithelia. Furthermore, alcohol consumption and tobacco use were strongly associated with the occurrence of oral cancer and were found to have a remarkable influence on TRPV1–4 receptor expression in normal oral mucosa. In particular, patients with a history of alcohol consumption demonstrated significantly higher expression levels. Conclusion Various external stimuli may influence the behavior of cancer cells. Overexpression of TRPV1-4 is likely to be a factor in enhanced sensitivity to external stimuli. These findings could contribute to the establishment of novel strategies for cancer therapy or prevention. PMID:28081185

  13. Villin promoter-mediated transgenic expression of transient receptor potential cation channel, subfamily V, member 6 (TRPV6) increases intestinal calcium absorption in wild-type and vitamin D receptor knockout mice.

    Science.gov (United States)

    Cui, Min; Li, Qiang; Johnson, Robert; Fleet, James C

    2012-10-01

    Transient receptor potential cation channel, subfamily V, member 6 (TRPV6) is an apical membrane calcium (Ca) channel in the small intestine proposed to be essential for vitamin D-regulated intestinal Ca absorption. Recent studies have challenged the proposed role for TRPV6 in Ca absorption. We directly tested intestinal TRPV6 function in Ca and bone metabolism in wild-type (WT) and vitamin D receptor knockout (VDRKO) mice. TRPV6 transgenic mice (TG) were made with intestinal epithelium-specific expression of a 3X Flag-tagged human TRPV6 protein. TG and VDRKO mice were crossed to make TG-VDRKO mice. Ca and bone metabolism was examined in WT, TG, VDRKO, and TG-VDRKO mice. TG mice developed hypercalcemia and soft tissue calcification on a chow diet. In TG mice fed a 0.25% Ca diet, Ca absorption was more than three-fold higher and femur bone mineral density (BMD) was 26% higher than WT. Renal 1α hydroxylase (CYP27B1) mRNA and intestinal expression of the natural mouse TRPV6 gene were reduced to intestine calbindin-D(9k) expression was elevated >15 times in TG mice. TG-VDRKO mice had high Ca absorption that prevented the low serum Ca, high renal CYP27B1 mRNA, low BMD, and abnormal bone microarchitecture seen in VDRKO mice. In addition, small intestinal calbindin D(9K) mRNA and protein levels were elevated in TG-VDRKO. Transgenic TRPV6 expression in intestine is sufficient to increase Ca absorption and bone density, even in VDRKO mice. VDR-independent upregulation of intestinal calbindin D(9k) in TG-VDRKO suggests this protein may buffer intracellular Ca during Ca absorption. © 2012 American Society for Bone and Mineral Research.

  14. Characterization of the starch-acting MaAmyB enzyme from Microbacterium aurum B8.A representing the novel subfamily GH13_42 with an unusual, multi-domain organization

    Science.gov (United States)

    Valk, Vincent; van der Kaaij, Rachel M.; Dijkhuizen, Lubbert

    2016-01-01

    The bacterium Microbacterium aurum strain B8.A degrades granular starches, using the multi-domain MaAmyA α-amylase to initiate granule degradation through pore formation. This paper reports the characterization of the M. aurum B8.A MaAmyB enzyme, a second starch-acting enzyme with multiple FNIII and CBM25 domains. MaAmyB was characterized as an α-glucan 1,4-α-maltohexaosidase with the ability to subsequently hydrolyze maltohexaose to maltose through the release of glucose. MaAmyB also displays exo-activity with a double blocked PNPG7 substrate, releasing PNP. In M. aurum B8.A, MaAmyB may contribute to degradation of starch granules by rapidly hydrolyzing the helical and linear starch chains that become exposed after pore formation by MaAmyA. Bioinformatics analysis showed that MaAmyB represents a novel GH13 subfamily, designated GH13_42, currently with 165 members, all in Gram-positive soil dwelling bacteria, mostly Streptomyces. All members have an unusually large catalytic domain (AB-regions), due to three insertions compared to established α-amylases, and an aberrant C-region, which has only 30% identity to established GH13 C-regions. Most GH13_42 members have three N-terminal domains (2 CBM25 and 1 FNIII). This is unusual as starch binding domains are commonly found at the C-termini of α-amylases. The evolution of the multi-domain M. aurum B8.A MaAmyA and MaAmyB enzymes is discussed. PMID:27808246

  15. Induction of excitatory and inhibitory presynaptic differentiation by GluD1.

    Science.gov (United States)

    Ryu, Kyounghee; Yokoyama, Marie; Yamashita, Manami; Hirano, Tomoo

    2012-01-06

    The δ subfamily of ionotropic glutamate receptor subunits consists of GluD1 and GluD2. GluD2, which is selectively expressed in cerebellar Purkinje neurons, has been shown to contribute to the formation of synapses between granule neurons and Purkinje neurons through interaction with Cbln1 (cerebellin precursor protein1) and presynaptic Neurexin. On the other hand, the synaptogenic activity of GluD1, which is expressed not in the cerebellum but in the hippocampus, remains to be characterized. Here, we report that GluD1 expressed in non-neuronal HEK cells, induced presynaptic differentiation of granule neurons through its N-terminal domain in co-cultures with cerebellar neurons, similarly to GluD2. We also show that GluD1 rescued the defect of synapse formation in GluD2-knockout Purkinje neurons, indicating the functional similarity of GluD1 and GluD2. In contrast, GluD1 expression alone did not induce presynaptic differentiation in co-cultures of HEK cells with hippocampal neurons. However, when Cbln1 was exogenously added to the culture medium, GluD1 induced presynaptic differentiation of not only glutamatergic presynaptic terminals but also GABAergic ones. Cbln1 is not expressed in hippocampal neurons but is expressed in entorhinal cortical neurons projecting to the hippocampus. In co-cultures of HEK cells expressing GluD1 and entorhinal cortical neurons, both glutamatergic and GABAergic presynaptic terminals were formed on the HEK cells without exogenous application of Cbln1. These results suggest that GluD1 might contribute to the formation of specific synapses in the hippocampus such as those formed by the projecting neurons of the entorhinal cortex.

  16. Differential expression profiling between the relative normal and dystrophic muscle tissues from the same LGMD patient

    Directory of Open Access Journals (Sweden)

    Yang Wei

    2006-12-01

    Full Text Available Abstract Background Limb-girdle muscular dystrophy (LGMD is a group of heterogeneous muscular disorders with autosomal dominant and recessive inheritance, in which the pelvic or shoulder girdle musculature is predominantly or primarily involved. Although analysis of the defective proteins has shed some light onto their functions implicated in the etiology of LGMD, our understanding of the molecular mechanisms underlying muscular dystrophy remains incomplete. Methods To give insight into the molecular mechanisms of AR-LGMD, we have examined the differentially expressed gene profiling between the relative normal and pathological skeletal muscles from the same AR-LGMD patient with the differential display RT-PCR approach. The research subjects came from a Chinese AR-LGMD family with three affected sisters. Results In this report, we have identified 31 known genes and 12 unknown ESTs, which were differentially expressed between the relative normal and dystrophic muscle from the same LGMD patient. The expression of many genes encoding structural proteins of skeletal muscle fibers (such as titin, myosin heavy and light chains, and nebulin were dramatically down-regulated in dystrophic muscles compared to the relative normal muscles. The genes, reticulocalbin 1, kinectin 1, fatty acid desaturase 1, insulin-like growth factor binding protein 5 (IGFBP5, Nedd4 family interacting protein 1 (NDFIP1, SMARCA2 (SWI/SNF related, matrix associated, actin dependent regulator of chromatin, subfamily a, member 2, encoding the proteins involved in signal transduction and gene expression regulation were up-regulated in the dystrophic muscles. Conclusion The functional analysis of these expression-altered genes in the pathogenesis of LGMD could provide additional information for understanding possible molecular mechanisms of LGMD development.

  17. A gene regulatory network for root epidermis cell differentiation in Arabidopsis.

    Directory of Open Access Journals (Sweden)

    Angela Bruex

    2012-01-01

    Full Text Available The root epidermis of Arabidopsis provides an exceptional model for studying the molecular basis of cell fate and differentiation. To obtain a systems-level view of root epidermal cell differentiation, we used a genome-wide transcriptome approach to define and organize a large set of genes into a transcriptional regulatory network. Using cell fate mutants that produce only one of the two epidermal cell types, together with fluorescence-activated cell-sorting to preferentially analyze the root epidermis transcriptome, we identified 1,582 genes differentially expressed in the root-hair or non-hair cell types, including a set of 208 "core" root epidermal genes. The organization of the core genes into a network was accomplished by using 17 distinct root epidermis mutants and 2 hormone treatments to perturb the system and assess the effects on each gene's transcript accumulation. In addition, temporal gene expression information from a developmental time series dataset and predicted gene associations derived from a Bayesian modeling approach were used to aid the positioning of genes within the network. Further, a detailed functional analysis of likely bHLH regulatory genes within the network, including MYC1, bHLH54, bHLH66, and bHLH82, showed that three distinct subfamilies of bHLH proteins participate in root epidermis development in a stage-specific manner. The integration of genetic, genomic, and computational analyses provides a new view of the composition, architecture, and logic of the root epidermal transcriptional network, and it demonstrates the utility of a comprehensive systems approach for dissecting a complex regulatory network.

  18. Practical Differential Profiling

    Energy Technology Data Exchange (ETDEWEB)

    Schulz, M; De Supinski, B R

    2007-02-04

    Comparing performance profiles from two runs is an essential performance analysis step that users routinely perform. In this work we present eGprof, a tool that facilitates these comparisons through differential profiling inside gprof. We chose this approach, rather than designing a new tool, since gprof is one of the few performance analysis tools accepted and used by a large community of users. eGprof allows users to 'subtract' two performance profiles directly. It also includes callgraph visualization to highlight the differences in graphical form. Along with the design of this tool, we present several case studies that show how eGprof can be used to find and to study the differences of two application executions quickly and hence can aid the user in this most common step in performance analysis. We do this without requiring major changes on the side of the user, the most important factor in guaranteeing the adoption of our tool by code teams.

  19. Differential scanning calorimetry.

    Science.gov (United States)

    Spink, Charles H

    2008-01-01

    Differential scanning calorimetry (DSC) has emerged as a powerful experimental technique for determining thermodynamic properties of biomacromolecules. The ability to monitor unfolding or phase transitions in proteins, polynucleotides, and lipid assemblies has not only provided data on thermodynamic stability for these important molecules, but also made it possible to examine the details of unfolding processes and to analyze the characteristics of intermediate states involved in the melting of biopolymers. The recent improvements in DSC instrumentation and software have generated new opportunities for the study of the effects of structure and changes in environment on the behavior of proteins, nucleic acids, and lipids. This review presents some of the details of application of DSC to the examination of the unfolding of biomolecules. After a brief introduction to DSC instrumentation used for the study of thermal transitions, the methods for obtaining basic thermodynamic information from the DSC curve are presented. Then, using DNA unfolding as an example, methods for the analysis of the melting transition are presented that allow deconvolution of the DSC curves to determine more subtle characteristics of the intermediate states involved in unfolding. Two types of transitions are presented for analysis, the first example being the unfolding of two large synthetic polynucleotides, which display high cooperativity in the melting process. The second example shows the application of DSC for the study of the unfolding of a simple hairpin oligonucleotide. Details of the data analysis are presented in a simple spreadsheet format.

  20. Glioma initiating cells form a differentiation niche via the induction of extracellular matrices and integrin αV.

    Directory of Open Access Journals (Sweden)

    Akiko Niibori-Nambu

    Full Text Available Glioma initiating cells (GICs are considered responsible for the therapeutic resistance and recurrence of malignant glioma. To clarify the molecular mechanism of GIC maintenance/differentiation, we established GIC clones having the potential to differentiate into malignant gliomas, and subjected to DNA microarray/iTRAQ based integrated proteomics. 21,857 mRNAs and 8,471 proteins were identified and integrated into a gene/protein expression analysis chart. Gene Ontology analysis revealed that the expression of cell adhesion molecules, including integrin subfamilies, such as α2 and αV, and extracellular matrices (ECMs, such as collagen IV (COL4, laminin α2 (LAMA2, and fibronectin 1 (FN, was significantly upregulated during serum-induced GIC differentiation. This differentiation process, accompanied by the upregulation of MAPK as well as glioma specific proteins in GICs, was dramatically accelerated in these ECM (especially FN-coated dishes. Integrin αV blocking antibody and RGD peptide significantly suppressed early events in GIC differentiation, suggesting that the coupling of ECMs to integrin αV is necessary for GIC differentiation. In addition, the expression of integrin αV and its strong ligand FN was prominently increased in glioblastomas developed from mouse intracranial GIC xenografts. Interestingly, during the initial phase of GIC differentiation, the RGD treatment significantly inhibited GIC proliferation and raised their sensitivity against anti-cancer drug temozolomide (TMZ. We also found that combination treatments of TMZ and RGD inhibit glioma progression and lead the longer survival of mouse intracranial GIC xenograft model. These results indicate that GICs induce/secrete ECMs to develop microenvironments with serum factors, namely differentiation niches that further stimulate GIC differentiation and proliferation via the integrin recognition motif RGD. A combination of RGD treatment with TMZ could have the higher inhibitory

  1. Intelligence Differentiation in Adult Samples.

    Science.gov (United States)

    Abad, Francisco J.; Colom, Robert; Juan-Espinosa, Manuel; Garcia, Luis F.

    2003-01-01

    Results for 3,340 participants taking a battery of cognitive tests and an analysis of the Spanish standardization of the Wechsler Adult Intelligence Scale-III support the differentiation of intelligence across the range of ability, with WAIS-III results more supportive of the differentiation theory. (SLD)

  2. Cognitive Differentiation in Intergroup Perception

    Science.gov (United States)

    Stephan, Walter G.

    1977-01-01

    Black, Chicano, and Anglo students from segregated and integrated schools perceived their ethnic groups as being less differentiated than outgroups. Students in integrated schools perceived outgroups as somewhat less differentiated than students in segregated schools. Intergroup contact, except between highly dissimilar groups, was not an…

  3. LUROTH'S THEOREM IN DIFFERENTIAL FIELDS

    Institute of Scientific and Technical Information of China (English)

    GAO Xiaoshan; XU Tao

    2002-01-01

    In this paper, we present a constructive proof of Liroth's theorem in differentialcase. We also give a method to find the inversion maps for general differential rationalparametric equations. As a consequence, we prove that a differential rational curve alwayshas a set of proper parametric equations.

  4. Thyroid differentiated carcinomas survey

    Energy Technology Data Exchange (ETDEWEB)

    Speich, P.V.; Couturier, M.; Mollet, E.; Bidet, R. (C.H.U., Besancon (France))

    1982-01-01

    We have adopted for the follow up of the differentiated thyroid carcinomas in adult cases, a protocol of control which is at the same time strict and not very constraining for the patient and which is based on two types of investigations. Most of your patients have been, at first, submitted for a total thyroidectomy which is followed with one or many therapeutic doses of 3700 MBq (100 mCi) of 131-Iodine and that to destroy thewhole of the thyroid tissue. The patients are then reexamined every six months and are submitted for a T4 opotherapeutic treatment the balance of a general check-up which includes a delicate clinic control, radiologic exam and biological exam, a general control of thyroid hormones, of the T.S.H. and the thyroglobulin and the antithyroglobulin antibodies. In case of any doubt, the balance sheet must be stopped and the patient which is suspected of having Iodine desaturation is submitted for a new general clinic and biologic check-up, which is accompanied with a total scanning after oral administration of 185 mBq (5 mCi) 131-Iodine. If this general check-up shows any active nodul, another therapeutic decision is taken which is often based on an new carcinologic dose of 131-Iodine. This treatment is always followed with a post therapeutic scanning 2 and 5 days later and than another new general check-up three months later to judge the efficiency of the treatment, and during this time the patient is compensed with a LT3.

  5. Prognostic Significance of Melanoma Differentiation and Trans-Differentiation

    Energy Technology Data Exchange (ETDEWEB)

    Maddodi, Nityanand; Setaluri, Vijayasaradhi, E-mail: setaluri@wisc.edu [Department of Dermatology, University of Wisconsin School of Medicine and Public Health, 1300 University Avenue, B25, Madison WI 53706 (United States)

    2010-05-26

    Cutaneous malignant melanomas share a number of molecular attributes such as limitless replicative potential that define capabilities acquired by most malignancies. Accordingly, much effort has been focused on evaluating and validating protein markers related to these capabilities to function as melanoma prognostic markers. However, a few studies have also highlighted the prognostic value of markers that define melanocytic differentiation and the plasticity of melanoma cells to trans-differentiate along several other cellular pathways. Here, we provide a comprehensive review and evaluation of the prognostic significance of melanocyte-lineage markers such as MITF and melanogenic proteins, as well as markers of vascular epithelial and neuronal differentiation.

  6. Differential localization of Mox-1 and Mox-2 proteins indicates distinct roles during development.

    Science.gov (United States)

    Candia, A F; Wright, C V

    1996-12-01

    Transcript localizations for Mox genes have implicated this homeobox gene subfamily in the early steps of mesoderm formation. We have extended these studies by determining the protein expression profile of Mox-1 and Mox-2 during mouse development. The time of onset of Mox protein expression has been accurately obtained to provide clues as to their roles during gastrulation. Expression of Mox-1 protein is first detected in the newly formed mesoderm of primitive streak stage mouse embryos (7.5 days post-coitum, d.p.c.). In contrast, Mox-2 protein is first detected at 9.0 d.p.c. in thr already formed somites. Additionally, immunostaining reveals new and distinct areas of Mox expression in the branchial arches and limbs that were not reported in our previous mRNA localization analysis. Mouse Mox-2 antibodies cross-react specifically in similar embryonic tissues in chick indicating the conservation of function of Mox genes in vertebrates. These expression data suggest that the Mox genes function transiently in the formation of mesodermal and mesenchymal derivatives, after their initial specification, but before their overt differentiation. Furthermore, while there appears to be some overlap in protein expression between Mox-1 and Mox-2 during somitogenesis, unique areas of expression indicate several distinct roles for the Mox genes during development.

  7. Cassava (Manihot esculenta Krantz) genome harbors KNOX genes differentially expressed during storage root development.

    Science.gov (United States)

    Guo, D; Li, H L; Tang, X; Peng, S Q

    2014-12-18

    In plants, homeodomain proteins play a critical role in regulating various aspects of plant growth and development. KNOX proteins are members of the homeodomain protein family. The KNOX transcription factors have been reported from Arabidopsis, rice, and other higher plants. The recent publication of the draft genome sequence of cassava (Manihot esculenta Krantz) has allowed a genome-wide search for M. esculenta KNOX (MeKNOX) transcription factors and the comparison of these positively identified proteins with their homologs in model plants. In the present study, we identified 12 MeKNOX genes in the cassava genome and grouped them into two distinct subfamilies based on their domain composition and phylogenetic analysis. Furthermore, semi-quantitative reverse transcription polymerase chain reaction analysis was performed to elucidate the expression profiles of these genes in different tissues and during various stages of root development. The analysis of MeKNOX expression profiles of indicated that 12 MeKNOX genes display differential expressions either in their transcript abundance or expression patterns.

  8. Two new species of the subfamily Tachininae (Diptera:Tachinidae) from the Liupan Mountains in Ningxia, China%中国宁夏六盘山寄蝇亚科二新种(双翅目:寄蝇科)

    Institute of Scientific and Technical Information of China (English)

    王强; 张春田

    2012-01-01

    记述采自宁夏六盘山区的寄蝇亚科2新种,宁夏透翅寄蝇Hyalurgus ningxiaensis sp.nov.和周氏密克寄蝇Mikia choui sp.nov.,分别隶属埃内寄蝇族Ernestini和寄蝇族Tachinini.宁夏透翅寄蝇外形与分布中国、俄罗斯和欧洲的亮透翅寄蝇H.lucidus相似,但新种额较窄,触角和足股节均黑色,翅r4+5室不闭合,无短柄,明显不同于后者;此外,新种也近似于分布我国的黄足透翅寄蝇H.flavipes,但新种额和颊均较窄,触角基节和梗节黑色,足股节也黑色,腹部第3、4背板均具多对侧心鬃,可区别于后者.周氏密克寄蝇外形与分布我国、印尼及印度的毛缘密克寄蝇M.apicali相似,但新种雌、雄胸部背板中鬃均2+3,翅前缘端半部无黑色斑.R4+5脉从基部到r-m脉段全部具小鬃,后足端位背鬃3根,腹部第1+2合背板无中缘鬃,可区别于后者.新种模式标本保存在沈阳师范大学昆虫标本室.%Two new species of the subfamily Tachininae from the Liupan Mountains in Ningxia,China are found and described:Hyalurgus ningxiaensis sp.nov.and Mikia choui sp.nov..The type specimens are preserved in the Liaoning Key Laboratory of Evolution and Biodiversity of Shenyang Normal University.

  9. Nuclear/nucleolar GTPase 2 proteins as a subfamily of YlqF/YawG GTPases function in pre-60S ribosomal subunit maturation of mono- and dicotyledonous plants.

    Science.gov (United States)

    Im, Chak Han; Hwang, Sung Min; Son, Young Sim; Heo, Jae Bok; Bang, Woo Young; Suwastika, I Nengah; Shiina, Takashi; Bahk, Jeong Dong

    2011-03-11

    The YlqF/YawG families are important GTPases involved in ribosome biogenesis, cell proliferation, or cell growth, however, no plant homologs have yet to be characterized. Here we isolated rice (Oryza sativa) and Arabidopsis nuclear/nucleolar GTPase 2 (OsNug2 and AtNug2, respectively) that belong to the YawG subfamily and characterized them for pre-60S ribosomal subunit maturation. They showed typical intrinsic YlqF/YawG family GTPase activities in bacteria and yeasts with k(cat) values 0.12 ± 0.007 min(-1) (n = 6) and 0.087 ± 0.002 min(-1) (n = 4), respectively, and addition of 60S ribosomal subunits stimulated their activities in vitro. In addition, OsNug2 rescued the lethality of the yeast nug2 null mutant through recovery of 25S pre-rRNA processing. By yeast two-hybrid screening five clones, including a putative one of 60S ribosomal proteins, OsL10a, were isolated. Subcellular localization and pulldown assays resulted in that the N-terminal region of OsNug2 is sufficient for nucleolar/nuclear targeting and association with OsL10a. OsNug2 is physically associated with pre-60S ribosomal complexes highly enriched in the 25S, 5.8S, and 5S rRNA, and its interaction was stimulated by exogenous GTP. Furthermore, the AtNug2 knockdown mutant constructed by the RNAi method showed defective growth on the medium containing cycloheximide. Expression pattern analysis revealed that the distribution of AtNug2 mainly in the meristematic region underlies its potential role in active plant growth. Finally, it is concluded that Nug2/Nog2p GTPase from mono- and didicotyledonous plants is linked to the pre-60S ribosome complex and actively processed 27S into 25S during the ribosomal large subunit maturation process, i.e. prior to export to the cytoplasm.

  10. Elements of partial differential equations

    CERN Document Server

    Sneddon, Ian N

    2006-01-01

    Geared toward students of applied rather than pure mathematics, this volume introduces elements of partial differential equations. Its focus is primarily upon finding solutions to particular equations rather than general theory.Topics include ordinary differential equations in more than two variables, partial differential equations of the first and second orders, Laplace's equation, the wave equation, and the diffusion equation. A helpful Appendix offers information on systems of surfaces, and solutions to the odd-numbered problems appear at the end of the book. Readers pursuing independent st

  11. Introduction to Piecewise Differentiable Equations

    CERN Document Server

    Scholtes, Stefan

    2012-01-01

    This brief provides an elementary introduction to the theory of piecewise differentiable functions with an emphasis on differentiable equations. In the first chapter, two sample problems are used to motivate the study of this theory. The presentation is then developed using two basic tools for the analysis of piecewise differentiable functions: the Bouligand derivative as the non smooth analogue of the classical derivative concept and the theory of piecewise affine functions as the combinatorial tool for the study of this approximation function. In the end, the results are combined to develop

  12. Differential forms on electromagnetic networks

    CERN Document Server

    Balasubramanian, N V; Sen Gupta, D P

    2013-01-01

    Differential Forms on Electromagnetic Networks deals with the use of combinatorial techniques in electrical circuit, machine analysis, and the relationship between circuit quantities and electromagnetic fields. The monograph is also an introduction to the organization of field equations by the methods of differential forms. The book covers topics such as algebraic structural relations in an electric circuit; mesh and node-pair analysis; exterior differential structures; generalized Stoke's theorem and tensor analysis; and Maxwell's electromagnetic equation. Also covered in the book are the app

  13. On Generalized Fractional Differentiator Signals

    Directory of Open Access Journals (Sweden)

    Hamid A. Jalab

    2013-01-01

    Full Text Available By employing the generalized fractional differential operator, we introduce a system of fractional order derivative for a uniformly sampled polynomial signal. The calculation of the bring in signal depends on the additive combination of the weighted bring-in of N cascaded digital differentiators. The weights are imposed in a closed formula containing the Stirling numbers of the first kind. The approach taken in this work is to consider that signal function in terms of Newton series. The convergence of the system to a fractional time differentiator is discussed.

  14. Differential forms theory and practice

    CERN Document Server

    Weintraub, Steven H

    2014-01-01

    Differential forms are utilized as a mathematical technique to help students, researchers, and engineers analyze and interpret problems where abstract spaces and structures are concerned, and when questions of shape, size, and relative positions are involved. Differential Forms has gained high recognition in the mathematical and scientific community as a powerful computational tool in solving research problems and simplifying very abstract problems through mathematical analysis on a computer. Differential Forms, 2nd Edition, is a solid resource for students and professionals needing a solid g

  15. Early Planetary Differentiation: Comparative Planetology

    Science.gov (United States)

    Jones, John H.

    2006-01-01

    We currently have extensive data for four different terrestrial bodies of the inner solar system: Earth, the Moon, Mars, and the Eucrite Parent Body [EPB]. All formed early cores; but all(?) have mantles with elevated concentrations of highly sidero-phile elements, suggestive of the addition of a late "veneer". Two appear to have undergone extensive differentiation consistent with a global magma ocean. One appears to be inconsistent with a simple model of "low-pressure" chondritic differentiation. Thus, there seems to be no single, simple paradigm for understand-ing early differentiation.

  16. Cloning and expression of two human genes encoding calcium-binding proteins that are regulated during myeloid differentiation

    Energy Technology Data Exchange (ETDEWEB)

    Lagasse, E.; Clerc, R.G.

    1988-06-01

    The cellular mechanisms involved in chronic inflammatory processes are poorly understood. This is especially true for the role of macrophages, which figure prominently in the inflammatory response. Two proteins, MRP8 and MRP14, which are expressed in infiltrate macrophages during inflammatory reactions but not in normal tissue macrophages, which have been characterized. Here the authors report that MRP8 and MRP14 mRNAs are specially expressed in human cells of myeloid origin and that their expression is regulated during monocycle-macrophage and granulocyte differentiation. To initiate the analysis of cis-acting elements governing the tissue-specific expression of the MRP genes, the authors cloned the human genes encoding MRP8 and MRP14. Both genes contain three exons, are single copy, and have a strikingly similar organization. They belong to a novel subfamily of highly homologous calcium-binding proteins which includes S100..cap alpha.., S100BETA, intestinal calcium-binding protein, P11, and calcyclin (2A9). A transient expression assay was devised to investigate the tissue-specific regulatory elements responsible for MRP gene expression after differentiation in leukemia HL60 cells. The results of this investigation demonstrated that the cis-acting element responsible for MRP expression are present on the cloned DNA fragment containing the MRP gene loci.

  17. Nash and Stackelberg Differential Games

    Institute of Scientific and Technical Information of China (English)

    Alain BENSOUSSAN; Jens FREHSE; Jens VOGELGESANG

    2012-01-01

    A large class of stochastic differential games for several players is considered in this paper.The class includes Nash differential games as well as Stackelberg differential games.A mix is possible.The existence of feedback strategies under general conditions is proved.The limitations concern the functionals in which the state and the controls appear separately.This is also true for the state equations.The controls appear in a quadratic form for the payoff and linearly in the state equation.The most serious restriction is the dimension of the state equation,which cannot exceed 2. The reason comes from PDE (partial differential equations) techniques used in studying the system of Bellman equations obtained by Dynamic Programming arguments.In the authors' previous work in 2002,there is not such a restriction,but there are serious restrictions on the structure of the Hamiltonians,which are violated in the applications dealt with in this article.

  18. Chiral anomalies and differential geometry

    Energy Technology Data Exchange (ETDEWEB)

    Zumino, B.

    1983-10-01

    Some properties of chiral anomalies are described from a geometric point of view. Topics include chiral anomalies and differential forms, transformation properties of the anomalies, identification and use of the anomalies, and normalization of the anomalies. 22 references. (WHK)

  19. Sexual differentiation in fission yeast

    DEFF Research Database (Denmark)

    Egel, R; Nielsen, O; Weilguny, D

    1990-01-01

    The regulation of sexual reproduction in yeast constitutes the highest level of differentiation observed in these unicellular organisms. The various ramifications of this system involve DNA rearrangement, transcriptional control, post-translational modification (such as protein phosphorylation) a...

  20. Introductory course on differential equations

    CERN Document Server

    Gorain, Ganesh C

    2014-01-01

    Introductory Course on DIFFERENTIAL EQUATIONS provides an excellent exposition of the fundamentals of ordinary and partial differential equations and is ideally suited for a first course of undergraduate students of mathematics, physics and engineering. The aim of this book is to present the elementary theories of differential equations in the forms suitable for use of those students whose main interest in the subject are based on simple mathematical ideas. KEY FEATURES: Discusses the subject in a systematic manner without sacrificing mathematical rigour. A variety of exercises drill the students in problem solving in view of the mathematical theories explained in the book. Worked out examples illustrated according to the theories developed in the book with possible alternatives. Exhaustive collection of problems and the simplicity of presentation differentiate this book from several others. Material contained will help teachers as well as aspiring students of different competitive examinations.

  1. Advances in discrete differential geometry

    CERN Document Server

    2016-01-01

    This is one of the first books on a newly emerging field of discrete differential geometry and an excellent way to access this exciting area. It surveys the fascinating connections between discrete models in differential geometry and complex analysis, integrable systems and applications in computer graphics. The authors take a closer look at discrete models in differential geometry and dynamical systems. Their curves are polygonal, surfaces are made from triangles and quadrilaterals, and time is discrete. Nevertheless, the difference between the corresponding smooth curves, surfaces and classical dynamical systems with continuous time can hardly be seen. This is the paradigm of structure-preserving discretizations. Current advances in this field are stimulated to a large extent by its relevance for computer graphics and mathematical physics. This book is written by specialists working together on a common research project. It is about differential geometry and dynamical systems, smooth and discrete theories, ...

  2. Taxonomia da subfamília Corinninae (Araneae, Corinnidae nas regiões neotropical e neártica Taxonomy of the subfamily Corinninae (Araneae, Corinnidae in neotropical and neartic regions

    Directory of Open Access Journals (Sweden)

    Alexandre Bragio Bonaldo

    2000-11-01

    Full Text Available The subfamily Corinninae is characterized and diagnosed. Two synapomorphies are hypothesized for the subfamily, both regarding the male palpal reservoir, which is primarily coiled and presents a sclerotized distal sector. Seventeen genera are recognized, six of which are new: Abapeba (type species Corinna lacertosa Simon, Erendira (type species Corinna pallidoguttata Simon, Septentrinna (type species Corinna bicalcarata Simon, Simonestus (type species Diestus validus Simon, Tapixaua (type species T. callida sp. nov. and Tupirinna (type species T. rosae sp. nov.. The genera Creugas Thorell, Falconina Brignoli and Paradiestus Mello-Leitão are revalidated. Diestus Simon and Lausus Simon are newly synonymized with Corinna C. L. Koch. Chemmis Simon is included in the synonymy of Megalostrata Karsch. Hypsinotus L. Koch is removed from the synonymy of Corinna and included in the synonymy of Creugas. Thirteen new species are described: Septentrinna yucatan and S. potosi from Mexico; Tupirinna rosae from Venezuela and Brazil; Tapixaua callida from Brazil and Peru; Abapeba hoeferi, A. rioclaro, A. taruma, Corinna ducke, C. colombo, C. mourai, C. recurva and Parachemmis manauara from Brazil; Creugas lisei from Brazil, Argentina and Uruguay. Twenty seven species are redescribed. Fifty eight new combinations are presented: from Chemmis, Septentrinna steckleri (Gertsch; from Corinna, Abapeba abalosi (Mello-Leitão, A. cleonei (Petrunkevitch, A. echinus (Simon, A. grassima (Chickering, A. guanicae (Petrunkevitch, A. lacertosa (Simon, A. luctuosa (F. O. Pickard-Cambridge, A. lugubris (Schenkel, A. pennata (Caporiacco, A. kochi (Petrunkevitch, A. saga (F. O. Pickard-Cambridge, A. wheeleri (Petrunkevitch, Creugas annamae (Gertsch & Davis, C. apophysarius (Caporiacco, C. bajulus (Gertsch, C. bellator (L. Koch, C. bicuspis (F.O. Pickard-Cambridge, C. epicureanus (Chamberlin, C. falculus (F. O. Pickard-Cambridge, C. mucronatus (F. O. Pickard-Cambridge, C. navus (F

  3. Partial Differential Equations of Physics

    OpenAIRE

    Geroch, Robert

    1996-01-01

    Apparently, all partial differential equations that describe physical phenomena in space-time can be cast into a universal quasilinear, first-order form. In this paper, we do two things. First, we describe some broad features of systems of differential equations so formulated. Examples of such features include hyperbolicity of the equations, constraints and their roles (e.g., in connection with the initial-value formulation), how diffeomorphism freedom is manifest, and how interactions betwee...

  4. Partial Differential Equations An Introduction

    OpenAIRE

    Choudary, A. D. R.; Parveen, Saima; Varsan, Constantin

    2010-01-01

    This book encompasses both traditional and modern methods treating partial differential equation (PDE) of first order and second order. There is a balance in making a selfcontained mathematical text and introducing new subjects. The Lie algebras of vector fields and their algebraic-geometric representations are involved in solving overdetermined of PDE and getting integral representation of stochastic differential equations (SDE). It is addressing to all scientists using PDE in treating mathe...

  5. Symmetries of partial differential equations

    OpenAIRE

    Gaussier, Hervé; Merker, Joël

    2004-01-01

    We establish a link between the study of completely integrable systems of partial differential equations and the study of generic submanifolds in C^n. Using the recent developments of Cauchy-Riemann geometry we provide the set of symmetries of such a system with a Lie group structure. Finally we determine the precise upper bound of the dimension of this Lie group for some specific systems of partial differential equations.

  6. Differential calculi on noncommutative bundles

    OpenAIRE

    Pflaum, Markus J.; Schauenburg, Peter

    1996-01-01

    We introduce a category of noncommutative bundles. To establish geometry in this category we construct suitable noncommutative differential calculi on these bundles and study their basic properties. Furthermore we define the notion of a connection with respect to a differential calculus and consider questions of existence and uniqueness. At the end these constructions are applied to basic examples of noncommutative bundles over a coquasitriangular Hopf algebra.

  7. Lecture Notes on Differential Forms

    OpenAIRE

    2016-01-01

    This is a series of lecture notes, with embedded problems, aimed at students studying differential topology. Many revered texts, such as Spivak's "Calculus on Manifolds" and Guillemin and Pollack's "Differential Topology" introduce forms by first working through properties of alternating tensors. Unfortunately, many students get bogged down with the whole notion of tensors and never get to the punch lines: Stokes' Theorem, de Rham cohomology, Poincare duality, and the realization of various t...

  8. Partial Differential Equations An Introduction

    CERN Document Server

    Choudary, A D R; Varsan, Constantin

    2010-01-01

    This book encompasses both traditional and modern methods treating partial differential equation (PDE) of first order and second order. There is a balance in making a selfcontained mathematical text and introducing new subjects. The Lie algebras of vector fields and their algebraic-geometric representations are involved in solving overdetermined of PDE and getting integral representation of stochastic differential equations (SDE). It is addressing to all scientists using PDE in treating mathematical methods.

  9. Multi-output differential technologies

    Science.gov (United States)

    Bidare, Srinivas R.

    1997-01-01

    A differential is a very old and proven mechanical device that allows a single input to be split into two outputs having equal torque irrespective of the output speeds. A standard differential is capable of providing only two outputs from a single input. A recently patented multi-output differential technology known as `Plural-Output Differential' allows a single input to be split into many outputs. This new technology is the outcome of a systematic study of complex gear trains (Bidare 1992). The unique feature of a differential (equal torque at different speeds) can be applied to simplify the construction and operation of many complex mechanical devices that require equal torque's or forces at multiple outputs. It is now possible to design a mechanical hand with three or more fingers with equal torque. Since these finger are powered via a differential they are `mechanically intelligent'. A prototype device is operational and has been used to demonstrate the utility and flexibility of the design. In this paper we shall review two devices that utilize the new technology resulting in increased performance, robustness with reduced complexity and cost.

  10. Comparison of two methods for customer differentiation

    NARCIS (Netherlands)

    A.F. Gabor (Adriana); Y. Guang (Yang); S. Axsäter (Sven)

    2014-01-01

    textabstractIn response to customer specific time guarantee requirements, service providers can offer differentiated ser- vices. However, conventional customer differentiation methods often lead to high holding costs and may have some practical drawbacks. We compare two customer differentiation poli

  11. Canonical FGFs Prevent Osteogenic Lineage Commitment and Differentiation of Human Bone Marrow Stromal Cells Via ERK1/2 Signaling.

    Science.gov (United States)

    Simann, Meike; Le Blanc, Solange; Schneider, Verena; Zehe, Viola; Lüdemann, Martin; Schütze, Norbert; Jakob, Franz; Schilling, Tatjana

    2017-02-01

    Controlling the adipo-osteogenic lineage decision of trabecular human bone marrow stromal cells (hBMSCs) in favor of osteogenesis represents a promising approach for osteoporosis therapy and prevention. Previously, Fibroblast Growth Factor 1 (FGF1) and its subfamily member FGF2 were scored as leading candidates to exercise control over skeletal precursor commitment and lineage decision albeit literature results are highly inconsistent. We show here that FGF1 and 2 strongly prevent the osteogenic commitment and differentiation of hBMSCs. Mineralization of extracellular matrix (ECM) and mRNA expression of osteogenic marker genes Alkaline Phosphatase (ALP), Collagen 1A1 (COL1A1), and Integrin-Binding Sialoprotein (IBSP) were significantly reduced. Furthermore, master regulators of osteogenic commitment like Runt-Related Transcription Factor 2 (RUNX2) and Bone Morphogenetic Protein 4 (BMP4) were downregulated. When administered under adipogenic culture conditions, canonical FGFs did not support osteogenic marker expression. Moreover despite the presence of osteogenic differentiation factors, FGFs even disabled the pro-osteogenic lineage decision of pre-differentiated adipocytic cells. In contrast to FGF Receptor 2 (FGFR2), FGFR1 was stably expressed throughout osteogenic and adipogenic differentiation and FGF addition. Moreover, FGFR1 and Extracellular Signal-Regulated Kinases 1 and 2 (ERK1/2) were found to be responsible for underlying signal transduction using respective inhibitors. Taken together, we present new findings indicating that canonical FGFR-ERK1/2 signaling entrapped hBMSCs in a pre-committed state and arrested further maturation of committed precursors. Our results might aid in unraveling and controlling check points relevant for ageing-associated aberrant adipogenesis with consequences for the treatment of degenerative diseases such as osteoporosis and for skeletal tissue engineering strategies. J. Cell. Biochem. 118: 263-275, 2017. © 2016 Wiley

  12. Genome-wide study of gene variants associated with differential cardiovascular event reduction by pravastatin therapy.

    Directory of Open Access Journals (Sweden)

    Dov Shiffman

    Full Text Available Statin therapy reduces the risk of coronary heart disease (CHD, however, the person-to-person variability in response to statin therapy is not well understood. We have investigated the effect of genetic variation on the reduction of CHD events by pravastatin. First, we conducted a genome-wide association study of 682 CHD cases from the Cholesterol and Recurrent Events (CARE trial and 383 CHD cases from the West of Scotland Coronary Prevention Study (WOSCOPS, two randomized, placebo-controlled studies of pravastatin. In a combined case-only analysis, 79 single nucleotide polymorphisms (SNPs were associated with differential CHD event reduction by pravastatin according to genotype (P<0.0001, and these SNPs were analyzed in a second stage that included cases as well as non-cases from CARE and WOSCOPS and patients from the PROspective Study of Pravastatin in the Elderly at Risk/PHArmacogenomic study of Statins in the Elderly at risk for cardiovascular disease (PROSPER/PHASE, a randomized placebo controlled study of pravastatin in the elderly. We found that one of these SNPs (rs13279522 was associated with differential CHD event reduction by pravastatin therapy in all 3 studies: P = 0.002 in CARE, P = 0.01 in WOSCOPS, P = 0.002 in PROSPER/PHASE. In a combined analysis of CARE, WOSCOPS, and PROSPER/PHASE, the hazard ratio for CHD when comparing pravastatin with placebo decreased by a factor of 0.63 (95% CI: 0.52 to 0.75 for each extra copy of the minor allele (P = 4.8 × 10(-7. This SNP is located in DnaJ homolog subfamily C member 5B (DNAJC5B and merits investigation in additional randomized studies of pravastatin and other statins.

  13. MEK5 suppresses osteoblastic differentiation

    Energy Technology Data Exchange (ETDEWEB)

    Kaneshiro, Shoichi [Department of Orthopaedic Surgery, Japan Community Health Care Organization Osaka Hospital, 4-2-78 Fukushima, Fukushima Ward, Osaka City, Osaka 553-0003 (Japan); Department of Orthopaedic Surgery, Graduate School of Medicine, Osaka University, 2-2 Yamadaoka, Suita, Osaka 565-0871 (Japan); Otsuki, Dai; Yoshida, Kiyoshi; Yoshikawa, Hideki [Department of Orthopaedic Surgery, Graduate School of Medicine, Osaka University, 2-2 Yamadaoka, Suita, Osaka 565-0871 (Japan); Higuchi, Chikahisa, E-mail: c-higuchi@umin.ac.jp [Department of Orthopaedic Surgery, Graduate School of Medicine, Osaka University, 2-2 Yamadaoka, Suita, Osaka 565-0871 (Japan)

    2015-07-31

    Extracellular signal-regulated kinase 5 (ERK5) is a member of the mitogen-activated protein kinase (MAPK) family and is activated by its upstream kinase, MAPK kinase 5 (MEK5), which is a member of the MEK family. Although the role of MEK5 has been investigated in several fields, little is known about its role in osteoblastic differentiation. In this study, we have demonstrated the role of MEK5 in osteoblastic differentiation in mouse preosteoblastic MC3T3-E1 cells and bone marrow stromal ST2 cells. We found that treatment with BIX02189, an inhibitor of MEK5, increased alkaline phosphatase (ALP) activity and the gene expression of ALP, osteocalcin (OCN) and osterix, as well as it enhanced the calcification of the extracellular matrix. Moreover, osteoblastic cell proliferation decreased at a concentration of greater than 0.5 μM. In addition, knockdown of MEK5 using siRNA induced an increase in ALP activity and in the gene expression of ALP, OCN, and osterix. In contrast, overexpression of wild-type MEK5 decreased ALP activity and attenuated osteoblastic differentiation markers including ALP, OCN and osterix, but promoted cell proliferation. In summary, our results indicated that MEK5 suppressed the osteoblastic differentiation, but promoted osteoblastic cell proliferation. These results implied that MEK5 may play a pivotal role in cell signaling to modulate the differentiation and proliferation of osteoblasts. Thus, inhibition of MEK5 signaling in osteoblasts may be of potential use in the treatment of osteoporosis. - Highlights: • MEK5 inhibitor BIX02189 suppresses proliferation of osteoblasts. • MEK5 knockdown and MEK5 inhibitor promote differentiation of osteoblasts. • MEK5 overexpression inhibits differentiation of osteoblasts.

  14. Stochastic differential equations, backward SDEs, partial differential equations

    CERN Document Server

    Pardoux, Etienne

    2014-01-01

    This research monograph presents results to researchers in stochastic calculus, forward and backward stochastic differential equations, connections between diffusion processes and second order partial differential equations (PDEs), and financial mathematics. It pays special attention to the relations between SDEs/BSDEs and second order PDEs under minimal regularity assumptions, and also extends those results to equations with multivalued coefficients. The authors present in particular the theory of reflected SDEs in the above mentioned framework and include exercises at the end of each chapter. Stochastic calculus and stochastic differential equations (SDEs) were first introduced by K. Itô in the 1940s, in order to construct the path of diffusion processes (which are continuous time Markov processes with continuous trajectories taking their values in a finite dimensional vector space or manifold), which had been studied from a more analytic point of view by Kolmogorov in the 1930s. Since then, this topic has...

  15. Differentiation, ageing, and terminal differentiation: a semantic analysis.

    Science.gov (United States)

    Reiner, J M

    1983-12-21

    The largely unsolved problems in the theoretical analysis of differentiation and ageing involve a substantial component of linguistic (semantic) difficulties. Some of these are simple traps of ambiguity, resulting from metaphorical or analogical employment of established terms--for example, "terminal differentiation" (loss of division potential in vitro) as a borrowing from "differentiation" as used by developmental biologists, or "commitment" by analogy with "determination". Some difficulties represent a failure to adopt (at least provisionally) an operational (empirical) view--for example, failure to ask what is the nature of the evidence for the view that a fertilized ovum is totipotential, or to scrutinize the evidence for the view that cells "terminally differentiated" in vitro in a conventional medium are in fact moribund under all conditions, or to examine more closely the view that the differentiated state and the cycling state are mutually exclusive. With respect to the problem of ageing, we review some of the critical experiments on "terminal differentiation" or "clonal senescence". We then proceed to consider some of the models that have been proposed, including a molecular model proposed by the author which appears to overcome some of the objections to other models. Some of the models exemplify the results of what are ultimately semantic vices. The problems with which these remarks began should indeed yield to the immense and novel resources of molecular biology. But the development of complete analyses demands not only good luck and delicate technique but also critical semantic clarity and severity. Given the best tools, we shall solve major theoretical problems only if we understand quite fully what problem it is that we are trying to solve--and the history of science illustrates that this is not as elementary a matter as it sounds.(ABSTRACT TRUNCATED AT 250 WORDS)

  16. Molecular clock hypothesis testing based on mitochondrial cytochrome b gene sequence of subfamily bovinae%以牛亚科家畜线粒体细胞色素b基因全序列检验分子钟假说

    Institute of Scientific and Technical Information of China (English)

    耿荣庆; 王兰萍; 常洪; 冀德君; 李永红; 常春芳

    2011-01-01

    To provide some objective data for accepting or refusing molecular clock hypothesis, non-parameter test method was employed based on mitochondrial cytochrome b gene sequence of six species of subfamily bovinae. The complete cytochrome b gene was 1 140 bp in length for all six bovine species and there was a little difference in base composition between species. Transition was the dominant base substitution model and the ratio of transition to transversion was 5.4. The testing results of relative evolution rate based on nucleotide sequences and amino acid sequences showed that molecular clock hypothesis was accepted absolutely within bovine species. The evolution of only a few sequences refused molecular clock hypothesis and evolution of most sequencesaccepted it among the species. It was easier to refuse molecular clock hypothesis based on the testing result from nucleotide sequence than the result from amino acid sequence. There was no obvious correlation between accepting or refusing molecular clock hypothesis and genetic distance between tested species. Molecular clock existed in some species. There was no nucleotide sequence or amino acid sequence varying in an absolutely stable rate in long evolution, and molecular clock was not unicersal.%在测定牛亚科家畜6个物种线粒体细胞色素b(Cyt b)基因全序列的基础上,以非参数检验法检验分子钟假说,提出肯定或否定分子钟假说的部分客观资料.结果表明,6个牛种的Cyt b基因全序列长度都是1140bp,牛种间序列的碱基组成差异较小,碱基替代以转换为主,转换/颠换比为5.4.基于核苷酸序列和氨基酸相对速率检验结果表明,牛种内序列的进化全部接受分子钟假说;牛种问大多数序列的进化接受分子钟假说,少数序列的进化拒绝分子钟假说.与基于氨基酸序列的检验结果相比较,基于核苷酸序列的检验结果更易于拒绝分子钟假说.进而推论,接受或者拒绝分子钟假说与所

  17. Studies on Neotropical Phasmatodea XVI: Revision of Haplopodini Günther, 1953 (rev. stat.), with notes on the subfamily Cladomorphinae Bradley & Galil, 1977 and the descriptions of a new tribe, four new genera and nine new species (Phasmatodea: "Anareolatae": Phasmatidae: Cladomorphinae).

    Science.gov (United States)

    Hennemann, Frank H; Conle, Oskar V; Perez-Gelabert, Daniel E

    2016-06-27

    eggs. Haplopodini Günther, 1953 is re-established (rev. stat.) and comprises almost exclusively Caribbean genera previously placed in Hesperophasmatini by Bradley & Galil (1977) or Cranidiini by Zompro, (2004). Aploploides Rehn & Hebard, 1938, Diapherodes Gray, 1835, Haplopus Burmeister, 1838 and Paracranidium Brock, 1998 were misplaced in Cranidiini and are transferred to Haplopodini. On the basis of numerous morphological characters of the insects and eggs Hesperophasmatini is removed from Pseudophasmatidae: Xerosomatinae and re-transferred to its previous position in the subfamily Cladomorphinae sensu lato. A detailed newdiagnosis of Hesperophasmatini is presented, but is only provisional since the true diversity is as yet only fractionally known. The lack of a gula distinguishes Hesperophasmatini from all other tribes. The genus Laciphorus Redtenbacher, 1908 is removed from Hesperophasmatini and transferred to Diapheromeridae: Diapheromerinae: Diapheromerini. The new tribe Pterinoxylini n. trib. is established to contain only the type-genus Pterinoxylus Audinet-Serville, 1838. It is closely related and perhaps the sister taxon of Hesperophasmatini, with which it shares the presence of rough sensory areas on the probasisternum and profurcasternum. It differs from Hesperophasmatini and Haplopodini by the presence of a tympanal region (= stridulatory organ) in the alae of females and the alveolar eggs, which possess peripheral opercular and polar structures. Haplopodini is likely to be the sister group of Pterinoxylini n. trib. + Hesperophasmatini.        The tribe Haplopodini rev. stat. is revised at the species level and comprises eight almost exclusively Caribbean genera, four of which are newly described. All eight genera now contained in Haplopodini are described in detail, differentiated from their closest relatives and their relationships and systematic position within Haplopodini are discussed. Keys and maps showing their distributions are presented

  18. ON NONLINEAR DIFFERENTIAL GALOIS THEORY

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Let X denote a complex analytic manifold, and let Aut(X) denote the space of invertible maps of a germ (X, a) to a germ (X, b); this space is obviously a groupoid; roughly speaking, a "Lie groupoid" is a subgroupoid of Aut(X) defined by a system of partial differential equations.To a foliation with singularities on X one attaches such a groupoid, e.g. the smallest one whose Lie algebra contains the vector fields tangent to the foliation. It is called "the Galois groupoid of the foliation". Some examples are considered, for instance foliations of codimension one, and foliations defined by linear differential equations; in this last case one recuperates the usual differential Galois group.

  19. INTERNATIONAL SPECIALIZATION AND VERTICAL DIFFERENTIATION

    Directory of Open Access Journals (Sweden)

    Furia Donatella

    2010-07-01

    Full Text Available During the last decades, market segmentation and intra-industry trade have become increasingly relevant. The underlying hypothesis of our work is that distinct articles have heterogeneous potential for vertical differentiation, implying that different patterns of international specialization should be identifiable. We carry out an analysis on revealed comparative advantage (through the Lafay Index in specific sectors of interest. Then we highlight the emergence of diverse degrees of product quality differentiation among sectors (through the Relative Quality Index. Results confirm our hypothesis. Indeed it appears that only certain goods, for which the pace of either creative or technological innovation (or both is particularly fast, present a high degree of vertical differentiation and market segmentation. This allows countries to specialize in a particular product variety and gain market power position for that variety. These findings should be taken in due consideration when designing trade policies.

  20. State space consistency and differentiability

    CERN Document Server

    Serakos, Demetrios

    2014-01-01

    By investigating the properties of the natural state, this book presents an analysis of input-output systems with regard to the mathematical concept of state. The state of a system condenses the effects of past inputs to the system in a useful manner. This monograph emphasizes two main properties of the natural state; the first has to do with the possibility of determining the input-output system from its natural state set and the second deals with differentiability properties involving the natural state inherited from the input-output system, including differentiability of the natural state and natural state trajectories. The results presented in this title aid in modeling physical systems since system identification from a state set holds in most models. Researchers and engineers working in electrical, aerospace, mechanical, and chemical fields along with applied mathematicians working in systems or differential equations will find this title useful due to its rigorous mathematics.  

  1. Differential equations methods and applications

    CERN Document Server

    Said-Houari, Belkacem

    2015-01-01

    This book presents a variety of techniques for solving ordinary differential equations analytically and features a wealth of examples. Focusing on the modeling of real-world phenomena, it begins with a basic introduction to differential equations, followed by linear and nonlinear first order equations and a detailed treatment of the second order linear equations. After presenting solution methods for the Laplace transform and power series, it lastly presents systems of equations and offers an introduction to the stability theory. To help readers practice the theory covered, two types of exercises are provided: those that illustrate the general theory, and others designed to expand on the text material. Detailed solutions to all the exercises are included. The book is excellently suited for use as a textbook for an undergraduate class (of all disciplines) in ordinary differential equations. .

  2. Algebrization of Nonautonomous Differential Equations

    Directory of Open Access Journals (Sweden)

    María Aracelia Alcorta-García

    2015-01-01

    Full Text Available Given a planar system of nonautonomous ordinary differential equations, dw/dt=F(t,w, conditions are given for the existence of an associative commutative unital algebra A with unit e and a function H:Ω⊂R2×R2→R2 on an open set Ω such that F(t,w=H(te,w and the maps H1(τ=H(τ,ξ and H2(ξ=H(τ,ξ are Lorch differentiable with respect to A for all (τ,ξ∈Ω, where τ and ξ represent variables in A. Under these conditions the solutions ξ(τ of the differential equation dξ/dτ=H(τ,ξ over A define solutions (x(t,y(t=ξ(te of the planar system.

  3. Solving Partial Differential Equations Using a New Differential Evolution Algorithm

    Directory of Open Access Journals (Sweden)

    Natee Panagant

    2014-01-01

    Full Text Available This paper proposes an alternative meshless approach to solve partial differential equations (PDEs. With a global approximate function being defined, a partial differential equation problem is converted into an optimisation problem with equality constraints from PDE boundary conditions. An evolutionary algorithm (EA is employed to search for the optimum solution. For this approach, the most difficult task is the low convergence rate of EA which consequently results in poor PDE solution approximation. However, its attractiveness remains due to the nature of a soft computing technique in EA. The algorithm can be used to tackle almost any kind of optimisation problem with simple evolutionary operation, which means it is mathematically simpler to use. A new efficient differential evolution (DE is presented and used to solve a number of the partial differential equations. The results obtained are illustrated and compared with exact solutions. It is shown that the proposed method has a potential to be a future meshless tool provided that the search performance of EA is greatly enhanced.

  4. Differential diagnosis of feline pruritus.

    Science.gov (United States)

    Foil, C S

    1988-09-01

    Pruritic skin diseases in the cat are best approached in a problem-oriented fashion. The presentations of pruritic skin disease in the cat include miliary dermatitis, pruritus of the head, scaling and crusting dermatoses, alopecia, erythroderma and exfoliation, eosinophilic granuloma complex, macular and pustular eruptions, and pruritic nodular dermatoses. There is a specific differential diagnosis for each presentation. A rational diagnostic plan, based on the likelihood of each disease in the differential diagnosis, may be formulated for each presentation of pruritus in the cat.

  5. Basic linear partial differential equations

    CERN Document Server

    Treves, Francois

    2006-01-01

    Focusing on the archetypes of linear partial differential equations, this text for upper-level undergraduates and graduate students features most of the basic classical results. The methods, however, are decidedly nontraditional: in practically every instance, they tend toward a high level of abstraction. This approach recalls classical material to contemporary analysts in a language they can understand, as well as exploiting the field's wealth of examples as an introduction to modern theories.The four-part treatment covers the basic examples of linear partial differential equations and their

  6. Spatial and Temporal Ray Differentials

    DEFF Research Database (Denmark)

    Sporring, Jon; Schjøth, Lars; Erleben, Kenny

    We consider ray bundles emanating from a source such as a camera or light source. We derive the full spatial and temporal structure to ¿rst order of the intersection of ray bundles with scene geometry, where scene geometry given as any implicit function. Further, we present the full details of 2...... often used geometrical representations. The ¿rst order structure may be used as the linear approximation of the change of photons as the camera, ob jects, and light source change as function of space and time. Our work generalises previous work on ray differentials [Igehy, 1999] and photon differentials...

  7. Group analysis of differential equations

    CERN Document Server

    Ovsiannikov, L V

    1982-01-01

    Group Analysis of Differential Equations provides a systematic exposition of the theory of Lie groups and Lie algebras and its application to creating algorithms for solving the problems of the group analysis of differential equations.This text is organized into eight chapters. Chapters I to III describe the one-parameter group with its tangential field of vectors. The nonstandard treatment of the Banach Lie groups is reviewed in Chapter IV, including a discussion of the complete theory of Lie group transformations. Chapters V and VI cover the construction of partial solution classes for the g

  8. Nielsen number and differential equations

    Directory of Open Access Journals (Sweden)

    Andres Jan

    2005-01-01

    Full Text Available In reply to a problem of Jean Leray (application of the Nielsen theory to differential equations, two main approaches are presented. The first is via Poincaré's translation operator, while the second one is based on the Hammerstein-type solution operator. The applicability of various Nielsen theories is discussed with respect to several sorts of differential equations and inclusions. Links with the Sharkovskii-like theorems (a finite number of periodic solutions imply infinitely many subharmonics are indicated, jointly with some further consequences like the nontrivial -structure of solutions of initial value problems. Some illustrating examples are supplied and open problems are formulated.

  9. Differential equations and mathematical biology

    CERN Document Server

    Jones, DS; Sleeman, BD

    2009-01-01

    ""… Much progress by these authors and others over the past quarter century in modeling biological and other scientific phenomena make this differential equations textbook more valuable and better motivated than ever. … The writing is clear, though the modeling is not oversimplified. Overall, this book should convince math majors how demanding math modeling needs to be and biologists that taking another course in differential equations will be worthwhile. The coauthors deserve congratulations as well as course adoptions.""-SIAM Review, Sept. 2010, Vol. 52, No. 3""… Where this text stands out i

  10. Full averaging of fuzzy impulsive differential inclusions

    Directory of Open Access Journals (Sweden)

    Natalia V. Skripnik

    2010-09-01

    Full Text Available In this paper the substantiation of the method of full averaging for fuzzy impulsive differential inclusions is studied. We extend the similar results for impulsive differential inclusions with Hukuhara derivative (Skripnik, 2007, for fuzzy impulsive differential equations (Plotnikov and Skripnik, 2009, and for fuzzy differential inclusions (Skripnik, 2009.

  11. Differential Calculus on N-Graded Manifolds

    OpenAIRE

    Sardanashvily, G.; W. Wachowski

    2017-01-01

    The differential calculus, including formalism of linear differential operators and the Chevalley–Eilenberg differential calculus, over N-graded commutative rings and on N-graded manifolds is developed. This is a straightforward generalization of the conventional differential calculus over commutative rings and also is the case of the differential calculus over Grassmann algebras and on Z2-graded manifolds. We follow the notion of an N-graded manifold as a local-ringed space whose body is a s...

  12. POLYMYOSITIS/DERMATOMIOSITIS: DIFFERENTIAL DIAGNOSIS

    Directory of Open Access Journals (Sweden)

    O. A. Antelava

    2016-01-01

    Full Text Available The lecture considers the problem of rare systemic connective tissue diseases, such as idiopathic inflammatory myopathies (IIMs. It underlines the clinical and immunological heterogeneity of their subtypes, which defines therapeutic tactics and prognosis. The diagnostic criteria for IIMs are given. A differential diagnostic algorithm based on the exclusion of phenotypically similar forms of myopathies of different genesis is proposed. 

  13. Differential equations a concise course

    CERN Document Server

    Bear, H S

    2011-01-01

    Concise introduction for undergraduates includes, among other topics, a survey of first order equations, discussions of complex-valued solutions, linear differential operators, inverse operators and variation of parameters method, the Laplace transform, Picard's existence theorem, and an exploration of various interpretations of systems of equations. Numerous clearly stated theorems and proofs, examples, and problems followed by solutions.

  14. Transcriptional profiling of epidermal differentiation.

    Science.gov (United States)

    Radoja, Nada; Gazel, Alix; Banno, Tomohiro; Yano, Shoichiro; Blumenberg, Miroslav

    2006-10-03

    In epidermal differentiation basal keratinocytes detach from the basement membrane, stop proliferating, and express a new set of structural proteins and enzymes, which results in an impermeable protein/lipid barrier that protects us. To define the transcriptional changes essential for this process, we purified large quantities of basal and suprabasal cells from human epidermis, using the expression of beta4 integrin as the discriminating factor. The expected expression differences in cytoskeletal, cell cycle, and adhesion genes confirmed the effective separation of the cell populations. Using DNA microarray chips, we comprehensively identify the differences in genes expressed in basal and differentiating layers of the epidermis, including the ECM components produced by the basal cells, the proteases in both the basal and suprabasal cells, and the lipid and steroid metabolism enzymes in suprabasal cells responsible for the permeability barrier. We identified the signaling pathways specific for the two populations and found two previously unknown paracrine and one juxtacrine signaling pathway operating between the basal and suprabasal cells. Furthermore, using specific expression signatures, we identified a new set of late differentiation markers and mapped their chromosomal loci, as well as a new set of melanocyte-specific markers. The data represent a quantum jump in understanding the mechanisms of epidermal differentiation.

  15. Pendulum Motion and Differential Equations

    Science.gov (United States)

    Reid, Thomas F.; King, Stephen C.

    2009-01-01

    A common example of real-world motion that can be modeled by a differential equation, and one easily understood by the student, is the simple pendulum. Simplifying assumptions are necessary for closed-form solutions to exist, and frequently there is little discussion of the impact if those assumptions are not met. This article presents a…

  16. Transcriptional networks controlling adipocyte differentiation

    DEFF Research Database (Denmark)

    Siersbæk, R; Mandrup, Susanne

    2011-01-01

    Adipocyte differentiation is regulated by a complex cascade of signals that drive the transcriptional reprogramming of the fibroblastic precursors. Genome-wide analyses of chromatin accessibility and binding of adipogenic transcription factors make it possible to generate "snapshots" of the trans...

  17. Multiple Intelligences for Differentiated Learning

    Science.gov (United States)

    Williams, R. Bruce

    2007-01-01

    There is an intricate literacy to Gardner's multiple intelligences theory that unlocks key entry points for differentiated learning. Using a well-articulated framework, rich with graphic representations, Williams provides a comprehensive discussion of multiple intelligences. He moves the teacher and students from curiosity, to confidence, to…

  18. Differential geometry meets the cell.

    Science.gov (United States)

    Marshall, Wallace F

    2013-07-18

    A new study by Terasaki et al. highlights the role of physical forces in biological form by showing that connections between stacked endoplasmic reticulum cisternae have a shape well known in classical differential geometry, the helicoid, and that this shape is a predictable consequence of membrane physics.

  19. Generalized fast automatic differentiation technique

    Science.gov (United States)

    Evtushenko, Yu. G.; Zubov, V. I.

    2016-11-01

    A new efficient technique intended for the numerical solution of a broad class of optimal control problems for complicated dynamical systems described by ordinary and/or partial differential equations is investigated. In this approach, canonical formulas are derived to precisely calculate the objective function gradient for a chosen finite-dimensional approximation of the objective functional.

  20. Cultural Differentiation of Negotiating Agents

    NARCIS (Netherlands)

    Hofstede, G.J.; Jonker, C.M.; Verwaart, D.

    2012-01-01

    Negotiations proceed differently across cultures. For realistic modeling of agents in multicultural negotiations, the agents must display culturally differentiated behavior. This paper presents an agent-based simulation model that tackles these challenges, based on Hofstede’s model of national cultu

  1. Cultural differentiation of negotiating agents

    NARCIS (Netherlands)

    Hofstede, G.J.; Jonker, C.M.; Verwaart, T.

    2010-01-01

    Negotiations proceed differently across cultures. For realistic modeling of agents in multicultural negotiations, the agents must display culturally differentiated behavior. This paper presents an agent-based simulation model that tackles these challenges, based on Hofstede’s model of national cultu

  2. On the path to differentiation

    DEFF Research Database (Denmark)

    Martinsen, Dorte Sindbjerg; Uygur, Ayca

    2014-01-01

    by examining the ‘path to differentiation’ within EU working time regulation as it has unfolded over time. It identifies the ‘opt-out’ as a means of differentiation adopted to overcome policy deadlocks within collective decision-making, albeit one with unforeseen consequences. In particular, the contribution...

  3. Stochastic nonlinear differential equations. I

    NARCIS (Netherlands)

    Heilmann, O.J.; Kampen, N.G. van

    1974-01-01

    A solution method is developed for nonlinear differential equations having the following two properties. Their coefficients are stochastic through their dependence on a Markov process. The magnitude of the fluctuations, multiplied with their auto-correlation time, is a small quantity. Under these co

  4. Differential operators and automorphism schemes

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    The ring of global differential operators of a variety is in closed and deep relation with its automorphism scheme.This relation can be applied to the study of homogeneous schemes,giving some criteria of homogeneity,a generalization of Serre-Lang theorem,and some consequences about abelian varieties.

  5. Experiments with a Differential Transformer

    Science.gov (United States)

    Aguilar, Horacio Munguía

    2016-01-01

    An experiment with an electric transformer based on single coils shows how electromagnetic induction changes when the magnetic coupling between coils is adjusted. This transformer has two secondary outputs which are taken differentially. This is the basis for a widely used position transducer known as LVDT.

  6. Pulmonary edema: radiographic differential diagnosis

    Energy Technology Data Exchange (ETDEWEB)

    Yoo, Dong Soo; Choi, Young Hi; Kim, Seung Cheol; An, Ji Hyun; Lee, Jee Young; Park, Hee Hong [Dankook Univ. College of Medicine, Chonan (Korea, Republic of)

    1997-04-01

    To evaluate the feasibility of using chest radiography to differentiate between three different etiologies of pulmonary edema. Plain chest radiographs of 77 patients, who were clinically confirmed as having pulmonary edema, were retrospectively reviewed. The patients were classified into three groups : group 1 (cardiogenic edema : n = 35), group 2 (renal pulmonary edema : n = 16) and group 3 (permeability edema : n = 26). We analyzed the radiologic findings of air bronchogram, heart size, peribronchial cuffing, septal line, pleural effusion, vascular pedicle width, pulmonary blood flow distribution and distribution of pulmonary edema. In a search for radiologic findings which would help in the differentiation of these three etiologies, each finding was assessed. Cardiogenic and renal pulmonary edema showed overlapping radiologic findings, except for pulmonary blood flow distribution. In cardiogenic pulmonary edema (n=35), cardiomegaly (n=29), peribronchial cuffing (n=29), inverted pulmonary blood flow distribution (n=21) and basal distribution of edema (n=20) were common. In renal pulmonary edema (n=16), cardiomegaly (n=15), balanced blood flow distribution (n=12), and central (n=9) or basal distribution of edema (n=7) were common. Permeability edema (n=26) showed different findings. Air bronchogram (n=25), normal blood flow distribution (n=14) and peripheral distribution of edema (n=21) were frequent findings, while cardiomegaly (n=7), peribronchial cuffing (n=7) and septal line (n=5) were observed in only a few cases. On plain chest radiograph, permeability edema can be differentiated from cardiogenic or renal pulmonary edema. The radiographic findings which most reliably differentiated these two etiologies were air bronchogram, distribution of pulmonary edema, peribronchial cuffing and heart size. Only blood flow distribution was useful for radiographic differentiation of cardiogenic and renal edema.

  7. Differentiation into Endoderm Lineage: Pancreatic differentiation from Embryonic Stem Cells

    OpenAIRE

    2011-01-01

    The endoderm gives rise to digestive and respiratory tracts, thyroid, liver, and pancreas. Representative disease of endoderm lineages is type 1 diabetes resulting from destruction of the insulin-producing β cells. Generation of functional β cells from human embryonic stem (ES) cells in vitro can be practical, renewable cell source for replacement cell therapy for type 1 diabetes. It has been achieved by progressive instructive differentiation through each of the developmental stages. In this...

  8. On the origin of differentiation

    Indian Academy of Sciences (India)

    J T Bonner

    2003-06-01

    Following the origin of multicellularity in many groups of primitive organisms there evolved more than one cell type. It has been assumed that this early differentiation is related to size – the larger the organism the more cell types. Here two very different kinds of organisms are considered: the volvocine algae that become multicellular by growth, and the cellular slime moulds that become multicellular by aggregation. In both cases there are species that have only one cell type and others that have two. It has been possible to show that there is a perfect correlation with size: the forms with two cell types are significantly larger than those with one. Also in both groups there are forms of intermediate size that will vary from one to two cell types depending on the size of the individuals, suggesting a form of quorum sensing. These observations reinforce the view that size plays a critical role in influencing the degree of differentiation.

  9. Differential growth of wrinkled biofilms

    CERN Document Server

    Espeso, D R; Einarsson, B

    2015-01-01

    Biofilms are antibiotic-resistant bacterial aggregates that grow on moist surfaces and can trigger hospital-acquired infections. They provide a classical example in biology where the dynamics of cellular communities may be observed and studied. Gene expression regulates cell division and differentiation, which affect the biofilm architecture. Mechanical and chemical processes shape the resulting structure. We gain insight into the interplay between cellular and mechanical processes during biofilm development on air-agar interfaces by means of a hybrid model. Cellular behavior is governed by stochastic rules informed by a cascade of concentration fields for nutrients, waste and autoinducers. Cellular differentiation and death alter the structure and the mechanical properties of the biofilm, which is deformed according to Foppl-Von Karman equations informed by cellular processes and the interaction with the substratum. Stiffness gradients due to growth and swelling produce wrinkle branching. We are able to repr...

  10. Reticulated acanthoma with sebaceous differentiation.

    Science.gov (United States)

    Fukai, Kazuyoshi; Sowa, Junko; Ishii, Masamitsu

    2006-04-01

    Reticulated acanthoma with sebaceous differentiation (RASD) is characterized by the reticulated proliferation of spinous cells with aggregates of mature sebocytes in the bases of the strands of the keratinocytes, often linking rete ridges. Here, we report the first case reported as RASD. A 55-year-old woman presented with a 15-year history of a slightly pruritic patch on the upper back, and the histology was typical for RASD. She had been bothered by a yellow discharge from the tumor. Skin tumors with sebaceous differentiation are occasionally associated with Muir-Torre syndrome. However, immunohistochemical staining for mutS homolog 2 (MSH-2) and mutL homolog 1 (MLH-1) showed positive staining within the nuclei of sebaceous cells and cells in the dermis. Therefore, it is most likely that the present case is not associated with Muir-Torre syndrome.

  11. Differential geometry and mathematical physics

    CERN Document Server

    Rudolph, Gerd

    2013-01-01

    Starting from an undergraduate level, this book systematically develops the basics of • Calculus on manifolds, vector bundles, vector fields and differential forms, • Lie groups and Lie group actions, • Linear symplectic algebra and symplectic geometry, • Hamiltonian systems, symmetries and reduction, integrable systems and Hamilton-Jacobi theory. The topics listed under the first item are relevant for virtually all areas of mathematical physics. The second and third items constitute the link between abstract calculus and the theory of Hamiltonian systems. The last item provides an introduction to various aspects of this theory, including Morse families, the Maslov class and caustics. The book guides the reader from elementary differential geometry to advanced topics in the theory of Hamiltonian systems with the aim of making current research literature accessible. The style is that of a mathematical textbook,with full proofs given in the text or as exercises. The material is illustrated by numerous d...

  12. Introduction to partial differential equations

    CERN Document Server

    Borthwick, David

    2016-01-01

    This modern take on partial differential equations does not require knowledge beyond vector calculus and linear algebra. The author focuses on the most important classical partial differential equations, including conservation equations and their characteristics, the wave equation, the heat equation, function spaces, and Fourier series, drawing on tools from analysis only as they arise.Within each section the author creates a narrative that answers the five questions: (1) What is the scientific problem we are trying to understand? (2) How do we model that with PDE? (3) What techniques can we use to analyze the PDE? (4) How do those techniques apply to this equation? (5) What information or insight did we obtain by developing and analyzing the PDE? The text stresses the interplay between modeling and mathematical analysis, providing a thorough source of problems and an inspiration for the development of methods.

  13. Age-differentiated work systems

    CERN Document Server

    Frieling, Ekkehart; Wegge, Jürgen

    2013-01-01

    The disproportionate aging of the population of working age in many nations around the world is a unique occurrence in the history of humankind. In the light of demographic change, it is becoming increasingly important to develop and use the potential of older employees. This edited volume Age-differentiated Work Systems provides a final report on a six-year priority program funded by the German Research Foundation (DFG) and presents selected research findings of 17 interdisciplinary project teams. The idea is that it will serve both as a reference book and overview of the current state of research in ergonomics, occupational psychology and related disciplines. It provides new models, methods, and procedures for analyzing and designing age-differentiated work systems with the aim of supporting subject matter experts from different areas in their decisions on labor and employment policies. Therefore over 40 laboratory experiments involving 2,000 participants and 50 field studies involving over 25,000 employees...

  14. Dynamics of partial differential equations

    CERN Document Server

    Wayne, C Eugene

    2015-01-01

    This book contains two review articles on the dynamics of partial differential equations that deal with closely related topics but can be read independently. Wayne reviews recent results on the global dynamics of the two-dimensional Navier-Stokes equations. This system exhibits stable vortex solutions: the topic of Wayne's contribution is how solutions that start from arbitrary initial conditions evolve towards stable vortices. Weinstein considers the dynamics of localized states in nonlinear Schrodinger and Gross-Pitaevskii equations that describe many optical and quantum systems. In this contribution, Weinstein reviews recent bifurcations results of solitary waves, their linear and nonlinear stability properties, and results about radiation damping where waves lose energy through radiation.   The articles, written independently, are combined into one volume to showcase the tools of dynamical systems theory at work in explaining qualitative phenomena associated with two classes of partial differential equ...

  15. Differentially Private Trajectory Data Publication

    CERN Document Server

    Chen, Rui; Desai, Bipin C

    2011-01-01

    With the increasing prevalence of location-aware devices, trajectory data has been generated and collected in various application domains. Trajectory data carries rich information that is useful for many data analysis tasks. Yet, improper publishing and use of trajectory data could jeopardize individual privacy. However, it has been shown that existing privacy-preserving trajectory data publishing methods derived from partition-based privacy models, for example k-anonymity, are unable to provide sufficient privacy protection. In this paper, motivated by the data publishing scenario at the Societe de transport de Montreal (STM), the public transit agency in Montreal area, we study the problem of publishing trajectory data under the rigorous differential privacy model. We propose an efficient data-dependent yet differentially private sanitization algorithm, which is applicable to different types of trajectory data. The efficiency of our approach comes from adaptively narrowing down the output domain by building...

  16. Numerical models for differential problems

    CERN Document Server

    Quarteroni, Alfio

    2014-01-01

    In this text, we introduce the basic concepts for the numerical modelling of partial differential equations. We consider the classical elliptic, parabolic and hyperbolic linear equations, but also the diffusion, transport, and Navier-Stokes equations, as well as equations representing conservation laws, saddle-point problems and optimal control problems. Furthermore, we provide numerous physical examples which underline such equations. We then analyze numerical solution methods based on finite elements, finite differences, finite volumes, spectral methods and domain decomposition methods, and reduced basis methods. In particular, we discuss the algorithmic and computer implementation aspects and provide a number of easy-to-use programs. The text does not require any previous advanced mathematical knowledge of partial differential equations: the absolutely essential concepts are reported in a preliminary chapter. It is therefore suitable for students of bachelor and master courses in scientific disciplines, an...

  17. [Differential diagnosis "vertigo and dizziness"].

    Science.gov (United States)

    Plontke, S K; Walther, L E

    2014-08-01

    Vertigo and dizziness are symptoms of interdisciplinary dimension. However, the differentiation and classification of vertigo syndromes also require experience and multidisciplinary knowledge. Since the clinical syndrome is subjective, a detailed analysis of the complaints underlying is required. International disease definitions are an indispensable tool in the differential diagnosis of vertigo syndromes today. With simple diagnostic tools eye movement disorders and nystagmus can be examined and assigned to specific vestibular disorders today. Screening tests (e.g. head impulse test) are now an important instrument in the investigation of patients with vertigo syndromes in case of emergency. With objective diagnostic methods (caloric irrigation, video head impulse test, vestibular evoked myogenic potentials) the degree of functional impairment of the five vestibular receptors can be assessed quantitatively. Furthermore, in vestibulopathies, a receptor and side-specific diagnostic assessment can be performed even with regard to dynamic aspects.

  18. Differential Equations for Morphological Amoebas

    Science.gov (United States)

    Welk, Martin; Breuß, Michael; Vogel, Oliver

    This paper is concerned with amoeba median filtering, a structure-adaptive morphological image filter. It has been introduced by Lerallut et al. in a discrete formulation. Experimental evidence shows that iterated amoeba median filtering leads to segmentation-like results that are similar to those obtained by self-snakes, an image filter based on a partial differential equation. We investigate this correspondence by analysing a space-continuous formulation of iterated median filtering. We prove that in the limit of vanishing radius of the structuring elements, iterated amoeba median filtering indeed approximates a partial differential equation related to self-snakes and the well-known (mean) curvature motion equation. We present experiments with discrete iterated amoeba median filtering that confirm qualitative and quantitative predictions of our analysis.

  19. Nielsen number and differential equations

    Directory of Open Access Journals (Sweden)

    Jan Andres

    2005-06-01

    Full Text Available In reply to a problem of Jean Leray (application of the Nielsen theory to differential equations, two main approaches are presented. The first is via Poincaré's translation operator, while the second one is based on the Hammerstein-type solution operator. The applicability of various Nielsen theories is discussed with respect to several sorts of differential equations and inclusions. Links with the Sharkovskii-like theorems (a finite number of periodic solutions imply infinitely many subharmonics are indicated, jointly with some further consequences like the nontrivial Rδ-structure of solutions of initial value problems. Some illustrating examples are supplied and open problems are formulated.

  20. Interpolation and partial differential equations

    OpenAIRE

    MALIGRANDA, Lech; Persson, Lars-Erik; Wyller, John

    1994-01-01

    One of the main motivations for developing the theory of interpolation was to apply it to the theory of partial differential equations (PDEs). Nowadays interpolation theory has been developed in an almost unbelievable way {see the bibliography of Maligranda [Interpolation of Operators and Applications (1926-1990), 2nd ed. (Luleå University, Luleå, 1993), p. 154]}. In this article some model examples are presented which display how powerful this theory is when dealing with PDEs. One main aim i...