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Sample records for pilus locus ebpr-ebpabc

  1. The presence of the pilus locus is a clonal property among pneumococcal invasive isolates

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    Melo-Cristino José

    2008-02-01

    Full Text Available Abstract Background Pili were recently recognized in Streptococcus pneumoniae and implicated in the virulence of this bacterium, which led to the proposal of using these antigens in a future pneumococcal vaccine. However, pili were found to be encoded by the rlrA islet that was not universally distributed in the species. We examined the distribution of the pilus islet, using the presence of the rlrA gene as a marker for the locus, among a collection of invasive isolates recovered in Portugal and analyzed its association with capsular serotypes, clusters defined by the pulsed-field gel electrophoretic profiles (PFGE and multilocus sequence types. Results Only a minority of the isolates were positive for the presence of the rlrA gene (27%. There was a high correspondence between the serotype and the presence or absence of rlrA (Wallace coefficient, W = 0.778. In particular, there was an association between the presence of rlrA and the vaccine serotypes 4, 6B, 9V and 14 whereas the gene was significantly absent from other serotypes, namely 1, 7F, 8, 12B and 23F, a group that included a vaccine serotype (23F and serotype 1 associated with enhanced invasiveness. Even within serotypes, there was variation in the presence of the pilus islet between PFGE clones and a higher Wallace coefficient (W = 0.939 indicates that carriage of the islet is a clonal property of pneumococci. Analysis of rlrA negative isolates revealed heterogeneity in the genomic region downstream of the rfl gene, the region where the islet is found in other isolates, compatible with recent loss of the islet in some lineages. Conclusion The pilus islet is present in a minority of pneumococcal isolates recovered from human invasive infections and is therefore not an essential virulence factor in these infections. Carriage of the pilus islet is a clonal property of pneumococci that may vary between isolates expressing the same serotype and loss and acquisition of the islet may be

  2. Activity of Bdellovibrio hit locus proteins, Bd0108 and Bd0109, links Type IVa pilus extrusion/retraction status to prey-independent growth signalling.

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    Michael J Capeness

    Full Text Available Bdellovibrio bacteriovorus are facultatively predatory bacteria that grow within gram-negative prey, using pili to invade their periplasmic niche. They also grow prey-independently on organic nutrients after undergoing a reversible switch. The nature of the growth switching mechanism has been elusive, but several independent reports suggested mutations in the hit (host-interaction locus on the Bdellovibrio genome were associated with the transition to prey-independent growth. Pili are essential for prey entry by Bdellovibrio and sequence analysis of the hit locus predicted that it was part of a cluster of Type IVb pilus-associated genes, containing bd0108 and bd0109. In this study we have deleted the whole bd0108 gene, which is unique to Bdellovibrio, and compared its phenotype to strains containing spontaneous mutations in bd0108 and the common natural 42 bp deletion variant of bd0108. We find that deletion of the whole bd0108 gene greatly reduced the extrusion of pili, whereas the 42 bp deletion caused greater pilus extrusion than wild-type. The pili isolated from these strains were comprised of the Type IVa pilin protein; PilA. Attempts to similarly delete gene bd0109, which like bd0108 encodes a periplasmic/secreted protein, were not successful, suggesting that it is likely to be essential for Bdellovibrio viability in any growth mode. Bd0109 has a sugar binding YD- repeat motif and an N-terminus with a putative pilin-like fold and was found to interact directly with Bd0108. These results lead us to propose that the Bd0109/Bd0108 interaction regulates pilus production in Bdellovibrio (possibly by interaction with the pilus fibre at the cell wall, and that the presence (and possibly retraction state of the pilus feeds back to alter the growth state of the Bdellovibrio cell. We further identify a novel small RNA encoded by the hit locus, the transcription of which is altered in different bd0108 mutation backgrounds.

  3. Fluctuations in type IV pilus retraction

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    Linden, M; Jonsson, A B; Wallin, M; Linden, Martin; Johansson, Emil; Jonsson, Ann-Beth; Wallin, Mats

    2005-01-01

    The type IV pilus retraction motor is found in many important bacterial pathogens. It is the strongest known linear motor protein and is required for bacterial infectivity. We characterize the dynamics of type IV pilus retraction in terms of a stochastic chemical reaction model. We find that a two state model can describe the experimental force velocity relation and qualitative dependence of ATP concentration. The results indicate that the dynamics is limited by an ATP-dependent step at low load and a force-dependent step at high load, and that at least one step is effectively irreversible in the measured range of forces. The irreversible nature of the sub-step(s) lead to interesting predictions for future experiments: We find different parameterizations with mathematically identical force velocity relations but different fluctuations (diffusion constant). We also find a longer elementary step compared to an earlier analysis, which agrees better with known facts about the structure of the pilus filament and e...

  4. The Streptococcus pneumoniae pilus-1 displays a biphasic expression pattern.

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    Gabriella De Angelis

    Full Text Available The Streptococcus pneumoniae pilus-1 is encoded by pilus islet 1 (PI-1, which has three clonal variants (clade I, II and III and is present in about 30% of clinical pneumococcal isolates. In vitro and in vivo assays have demonstrated that pilus-1 is involved in attachment to epithelial cells and virulence, as well as protection in mouse models of infection. Several reports suggest that pilus-1 expression is tightly regulated and involves the interplay of numerous genetic regulators, including the PI-1 positive regulator RlrA. In this report we provide evidence that pilus expression, when analyzed at the single-cell level in PI-1 positive strains, is biphasic. In fact, the strains present two phenotypically different sub-populations of bacteria, one that expresses the pilus, while the other does not. The proportions of these two phenotypes are variable among the strains tested and are not influenced by genotype, serotype, growth conditions, colony morphology or by the presence of antibodies directed toward the pilus components. Two sub-populations, enriched in pilus expressing or not expressing bacteria were obtained by means of colony selection and immuno-detection methods for five strains. PI-1 sequencing in the two sub-populations revealed the absence of mutations, thus indicating that the biphasic expression observed is not due to a genetic modification within PI-1. Microarray expression profile and western blot analyses on whole bacterial lysates performed comparing the two enriched sub-populations, revealed that pilus expression is regulated at the transcriptional level (on/off regulation, and that there are no other genes, in addition to those encoded by PI-1, concurrently regulated across the strains tested. Finally, we provide evidence that the over-expression of the RrlA positive regulator is sufficient to induce pilus expression in pilus-1 negative bacteria. Overall, the data presented here suggest that the observed biphasic pilus

  5. Examination of type IV pilus expression and pilus-associated phenotypes in Kingella kingae clinical isolates.

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    Kehl-Fie, Thomas E; Porsch, Eric A; Yagupsky, Pablo; Grass, Elizabeth A; Obert, Caroline; Benjamin, Daniel K; St Geme, Joseph W

    2010-04-01

    Kingella kingae is a gram-negative bacterium that is being recognized increasingly as a cause of septic arthritis and osteomyelitis in young children. Previous work established that K. kingae expresses type IV pili that mediate adherence to respiratory epithelial and synovial cells. PilA1 is the major pilus subunit in K. kingae type IV pili and is essential for pilus assembly. To develop a better understanding of the role of K. kingae type IV pili during colonization and invasive disease, we examined a collection of clinical isolates for pilus expression and in vitro adherence. In addition, in a subset of isolates we performed nucleotide sequencing to assess the level of conservation of PilA1. The majority of respiratory and nonendocarditis blood isolates were piliated, while the majority of joint fluid, bone, and endocarditis blood isolates were nonpiliated. The piliated isolates formed either spreading/corroding or nonspreading/noncorroding colonies and were uniformly adherent, while the nonpiliated isolates formed domed colonies and were nonadherent. PilA1 sequence varied significantly from strain to strain, resulting in substantial variability in antibody reactivity. These results suggest that type IV pili may confer a selective advantage on K. kingae early in infection and a selective disadvantage on K. kingae at later stages in the pathogenic process. We speculate that PilA1 is immunogenic during natural infection and undergoes antigenic variation to escape the immune response.

  6. Examination of Type IV Pilus Expression and Pilus-Associated Phenotypes in Kingella kingae Clinical Isolates▿

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    Kehl-Fie, Thomas E.; Porsch, Eric A.; Yagupsky, Pablo; Grass, Elizabeth A.; Obert, Caroline; Benjamin, Daniel K.; St. Geme, Joseph W.

    2010-01-01

    Kingella kingae is a gram-negative bacterium that is being recognized increasingly as a cause of septic arthritis and osteomyelitis in young children. Previous work established that K. kingae expresses type IV pili that mediate adherence to respiratory epithelial and synovial cells. PilA1 is the major pilus subunit in K. kingae type IV pili and is essential for pilus assembly. To develop a better understanding of the role of K. kingae type IV pili during colonization and invasive disease, we examined a collection of clinical isolates for pilus expression and in vitro adherence. In addition, in a subset of isolates we performed nucleotide sequencing to assess the level of conservation of PilA1. The majority of respiratory and nonendocarditis blood isolates were piliated, while the majority of joint fluid, bone, and endocarditis blood isolates were nonpiliated. The piliated isolates formed either spreading/corroding or nonspreading/noncorroding colonies and were uniformly adherent, while the nonpiliated isolates formed domed colonies and were nonadherent. PilA1 sequence varied significantly from strain to strain, resulting in substantial variability in antibody reactivity. These results suggest that type IV pili may confer a selective advantage on K. kingae early in infection and a selective disadvantage on K. kingae at later stages in the pathogenic process. We speculate that PilA1 is immunogenic during natural infection and undergoes antigenic variation to escape the immune response. PMID:20145101

  7. Structure of the Vibrio cholerae Type IVb Pilus and stability comparison with the Neisseria gonorrhoeae type IVa pilus.

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    Li, Juliana; Egelman, Edward H; Craig, Lisa

    2012-04-20

    Type IV pili are multifunctional filaments displayed on many bacterial pathogens. Members of the Type IVa pilus subclass are found on a diverse group of human pathogens, whereas Type IVb pili are found almost exclusively on enteric bacteria. The Type IVa and IVb subclasses are distinguished by differences in the pilin subunits, including the fold of the globular domain. To understand the implications of the distinct pilin folds, we compared the stabilities of pilin subunits and pilus filaments for the Type IVa GC pilus from Neisseria gonorrhoeae and the Type IVb toxin-coregulated pilus (TCP) from Vibrio cholerae. We show that while recombinant TCP pilin is more stable than GC pilin, the GC pili are more resistant to proteolysis, heat and chemical denaturation than TCP, remaining intact in 8 M urea. To understand these differences, we determined the TCP structure by electron microscopy and three-dimensional image reconstruction. TCP have an architecture similar to that of GC pili, with subunits arranged in a right-handed 1-start helix and related by an 8.4-Å axial rise and a 96.8° azimuthal rotation. However, the TCP subunits are not as tightly packed as GC pilins, and the distinct Type IVb pilin fold exposes a segment of the α-helical core of TCP. Hydrophobic interactions dominate for both pilus subtypes, but base stacking by aromatic residues conserved among the Type IVa pilins may contribute to GC pilus stability. The extraordinary stability of GC pili may represent an adaptation of the Type IVa pili to harsh environments and the need to retract against external forces. Copyright © 2012 Elsevier Ltd. All rights reserved.

  8. Duplication of pilus gene complexes of Haemophilus influenzae biogroup aegyptius.

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    Read, T D; Dowdell, M; Satola, S W; Farley, M M

    1996-11-01

    Brazilian purpuric fever (BPF) is a recently described pediatric septicemia caused by a strain of Haemophilus influenzae biogroup aegyptius. The pilus specified by this bacterium may be important in BPF pathogenesis, enhancing attachment to host tissue. Here, we report the cloning of two haf (for H. influenzae biogroup aegyptius fimbriae) gene clusters from a cosmid library of strain F3031. We sequenced a 6.8-kb segment of the haf1 cluster and identified five genes (hafA to hafE). The predicted protein products, HafA to HafD, are 72, 95, 98, and 90% similar, respectively, to HifA to HifD of the closely related H. influenzae type b pilus. Strikingly, the putative pilus adhesion, HifE, shares only 44% identity with HafE, suggesting that the proteins may differ in receptor specificity. Insertion of a mini-gammadelta transposon in the hafE gene eliminated hemadsorption. The nucleotide sequences of the haf1 and haf2 clusters are more than 99% identical. Using the recently published sequence of the H. influenzae Rd genome, we determined that the haf1 complex lies at a unique position in the chromosome between the pmbA gene and a hypothetical open reading frame, HI1153. The location of the haf2 cluster, inserted between the purE and pepN genes, is analogous to the hif genes on H. influenzae type b. BPF fimbrial phase switching appears to involve slip-strand mispairing of repeated dinucleotides in the pilus promoter. The BPF-associated H. influenzae biogroup aegyptius pilus system generally resembles other H. influenzae, but the possession of a second fimbrial gene cluster, which appears to have arisen by a recent duplication event, and the novel sequence of the HafE adhesin may be significant in the unusual pathogenesis of BPF.

  9. Evidence that a modified type IV pilus-like system powers gliding motility and polysaccharide secretion in filamentous cyanobacteria.

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    Khayatan, Behzad; Meeks, John C; Risser, Douglas D

    2015-12-01

    In filamentous cyanobacteria, the mechanism of gliding motility is undefined but posited to be driven by a polysaccharide secretion system known as the junctional pore complex (JPC). Recent evidence implies that the JPC is a modified type IV pilus-like structure encoded for in part by genes in the hps locus. To test this hypothesis, we conducted genetic, cytological and comparative genomics studies on hps and pil genes in Nostoc punctiforme, a species in which motility is restricted to transiently differentiated filaments called hormogonia. Inactivation of most hps and pil genes abolished motility and abolished or drastically reduced secretion of hormogonium polysaccharide, and the subcellular localization of several Pil proteins in motile hormogonia corresponds to the site of the junctional pore complex. The non-motile ΔhpsE-G strain, which lacks three glycosyltransferases that synthesize hormogonium polysaccharide, could be complemented to motility by the addition of medium conditioned by wild-type hormogonia. Based on this result, we speculate that secretion of hormogonium polysaccharide facilitates but does not provide the motive force for gliding. Both the Hps and Pil homologs characterized in this study are almost universally conserved among filamentous cyanobacteria, with the Hps homologs rarely found in unicellular strains. These results support the theory that Hps and Pil proteins compose the JPC, a type IV pilus-like nanomotor that drives motility and polysaccharide secretion in filamentous cyanobacteria.

  10. Mitis group streptococci express variable pilus islet 2 pili.

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    Dorothea Zähner

    Full Text Available BACKGROUND: Streptococcus oralis, Streptococcus mitis, and Streptococcus sanguinis are members of the Mitis group of streptococci and agents of oral biofilm, dental plaque and infective endocarditis, disease processes that involve bacteria-bacteria and bacteria-host interactions. Their close relative, the human pathogen S. pneumoniae uses pilus-islet 2 (PI-2-encoded pili to facilitate adhesion to eukaryotic cells. METHODOLOGY/PRINCIPAL FINDINGS: PI-2 pilus-encoding genetic islets were identified in S. oralis, S. mitis, and S. sanguinis, but were absent from other isolates of these species. The PI-2 islets resembled the genetic organization of the PI-2 islet of S. pneumoniae, but differed in the genes encoding the structural pilus proteins PitA and PitB. Two and three variants of pitA (a pseudogene in S. pneumoniae and pitB, respectively, were identified that showed ≈20% difference in nucleotide as well as corresponding protein sequence. Species-independent combinations of pitA and pitB variants indicated prior intra- and interspecies horizontal gene transfer events. Polyclonal antisera developed against PitA and PitB of S. oralis type strain ATCC35037 revealed that PI-2 pili in oral streptococci were composed of PitA and PitB. Electronmicrographs showed pilus structures radiating >700 nm from the bacterial surface in the wild type strain, but not in an isogenic PI-2 deletion mutant. Anti-PitB-antiserum only reacted with pili containing the same PitB variant, whereas anti-PitA antiserum was cross-reactive with the other PitA variant. Electronic multilocus sequence analysis revealed that all PI-2-encoding oral streptococci were closely-related and cluster with non-PI-2-encoding S. oralis strains. CONCLUSIONS/SIGNIFICANCE: This is the first identification of PI-2 pili in Mitis group oral streptococci. The findings provide a striking example of intra- and interspecies horizontal gene transfer. The PI-2 pilus diversity provides a possible key to

  11. Scanning probe studies of the pilus nanowires in Geobacter sulfurreducens

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    Veazey, Joshua P.

    In microbial organisms like bacteria, pili (singular: pilus) are filament-like appendages that are nanometers in diameter and microns long. The sizes and structures of the different types of pili found in nature are adapted to serve one of many distinct functions for the organism from which they come. The pili expressed by the bacterium Geobacter sulfurreducens act as electrically conductive nanowires that provide conduits for electrons to leave the cell during its respiratory cycle. Biological experiments have suggested that long range electron transfer across micron distances may proceed along the protein matrix, rather than by metal cofactors (metal atoms bound to the protein). Protein conductivity across such distances would require a novel transport mechanism. In an effort to elucidate this mechanism, our lab has used two electronically sensitive scanning probe techniques: Scanning Tunneling Microscopy (STM) and Conductive Probe Atomic Force Microscopy (CP-AFM). I employed the high resolution imaging and electronic sensitivity of STM to resolve the molecular sub-structure and local electronic density of states (LDOS) at different points above pili from purified preparations, deposited onto a conducting substrate. The significant and stable tunneling currents achieved for biologically relevant voltages, in the absence of metal cofactors, demonstrated conduction between tip and substrate via the protein matrix. We observed periodicity of roughly 10 nm and 2.5 nm in topographs of the pili. In our acquisition of LDOS, we observed gap-like asymmetric energy spectra that were dependent upon the location of the tip above the pilus, suggestive of easier current flow out of one side of the cylindrical pilus and into the opposite side. Voltage-dependent STM imaging, which also contains information about the LDOS at each pixel, was consistent with this interpretation. The asymmetry in spectra observed on one pilus edge had a slightly larger magnitude than the other edge

  12. Hybrid Structure of the Type 1 Pilus of Uropathogenic Escherichia coli.

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    Habenstein, Birgit; Loquet, Antoine; Hwang, Songhwan; Giller, Karin; Vasa, Suresh Kumar; Becker, Stefan; Habeck, Michael; Lange, Adam

    2015-09-28

    Type 1 pili are filamentous protein assemblies on the surface of Gram-negative bacteria that mediate adhesion to host cells during the infection process. The molecular structure of type 1 pili remains elusive on the atomic scale owing to their insolubility and noncrystallinity. Herein we describe an approach for hybrid-structure determination that is based on data from solution-state NMR spectroscopy on the soluble subunit and solid-state NMR spectroscopy and STEM data on the assembled pilus. Our approach is based on iterative modeling driven by structural information extracted from different sources and provides a general tool to access pseudo atomic structures of protein assemblies with complex subunit folds. By using this methodology, we determined the local conformation of the FimA pilus subunit in the context of the assembled type 1 pilus, determined the exact helical pilus architecture, and elucidated the intermolecular interfaces contributing to pilus assembly and stability with atomic detail.

  13. Noncanonical sortase-mediated assembly of pilus type 2b in group B Streptococcus.

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    Lazzarin, Maddalena; Cozzi, Roberta; Malito, Enrico; Martinelli, Manuele; D'Onofrio, Mariapina; Maione, Domenico; Margarit, Immaculada; Rinaudo, C Daniela

    2015-11-01

    Group B Streptococcus (GBS) expresses 3 structurally distinct pilus types (1, 2a, and 2b) identified as important virulence factors and vaccine targets. These pili are heterotrimeric polymers, covalently assembled on the cell wall by sortase (Srt) enzymes. We investigated the pilus-2b biogenesis mechanism by using a multidisciplinary approach integrating genetic, biochemical, and structural studies to dissect the role of the 2 pilus-2b-associated Srts. We show that only 1 sortase (SrtC1-2b) is responsible for pilus protein polymerization, whereas the second one (Srt2-2b) does not act as a pilin polymerase, but similarly to the housekeeping class A Srt (SrtA), it is involved in cell-wall pilus anchoring by targeting the minor ancillary subunit. Based on its function and sequence features, Srt2-2b does not belong to class C Srts (SrtCs), nor is it a canonical member of any other known family of Srts. We also report the crystal structure of SrtC1-2b at 1.9 Å resolution. The overall fold resembles the typical structure of SrtCs except for the N-terminal lid region that appears in an open conformation displaced from the active site. Our findings reveal that GBS pilus type 2b biogenesis differs significantly from the current model of pilus assembly in gram-positive pathogens.

  14. A type IV pilus mediates DNA binding during natural transformation in Streptococcus pneumoniae.

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    Raphaël Laurenceau

    Full Text Available Natural genetic transformation is widely distributed in bacteria and generally occurs during a genetically programmed differentiated state called competence. This process promotes genome plasticity and adaptability in Gram-negative and Gram-positive bacteria. Transformation requires the binding and internalization of exogenous DNA, the mechanisms of which are unclear. Here, we report the discovery of a transformation pilus at the surface of competent Streptococcus pneumoniae cells. This Type IV-like pilus, which is primarily composed of the ComGC pilin, is required for transformation. We provide evidence that it directly binds DNA and propose that the transformation pilus is the primary DNA receptor on the bacterial cell during transformation in S. pneumoniae. Being a central component of the transformation apparatus, the transformation pilus enables S. pneumoniae, a major Gram-positive human pathogen, to acquire resistance to antibiotics and to escape vaccines through the binding and incorporation of new genetic material.

  15. Extracellular polysaccharides mediate pilus retraction during social motility of Myxococcus xanthus.

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    Li, Yinuo; Sun, Hong; Ma, Xiaoyuan; Lu, Ann; Lux, Renate; Zusman, David; Shi, Wenyuan

    2003-04-29

    Myxococcus xanthus is a Gram-negative bacterium with a complex life cycle that includes vegetative swarming and fruiting-body formation. Social (S)-motility (coordinated movement of large cell groups) requires both type IV pili and fibrils (extracellular matrix material consisting of polysaccharides and protein). Little is known about the role of this extracellular matrix, or fibril material, in pilus-dependent motility. In this study, mutants lacking fibril material and, therefore, S-motility were found to be hyperpiliated. We demonstrated that addition of fibril material resulted in pilus retraction and rescued this phenotype. The fibril material was further examined to determine the component(s) that were responsible for triggering pilus retraction. Protein-free fibril material was found to be highly active in correcting hyperpiliation. However, the amine sugars present in hydrolyzed fibril material, e.g., glucosamine and N-acetylglucosamine (GlcNAc) had no effect on fibril(-) mutants, but, interestingly, cause hyperpiliation in wild-type cells. In contrast, chitin, a natural GlcNAc polymer, was found to restore pilus retraction in hyperpiliated mutants, indicating that a polysaccharide containing amine sugars is likely required for pilus retraction. These data suggest that the interaction of type IV pili with amine-containing polysaccharides on cell and slime-trail surfaces may trigger pilus retraction, resulting in S-motility and slime-trailing behaviors.

  16. Functional identification of conserved residues involved in Lactobacillus rhamnosus strain GG sortase specificity and pilus biogenesis.

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    Douillard, François P; Rasinkangas, Pia; von Ossowski, Ingemar; Reunanen, Justus; Palva, Airi; de Vos, Willem M

    2014-05-30

    In Gram-positive bacteria, sortase-dependent pili mediate the adhesion of bacteria to host epithelial cells and play a pivotal role in colonization, host signaling, and biofilm formation. Lactobacillus rhamnosus strain GG, a well known probiotic bacterium, also displays on its cell surface mucus-binding pilus structures, along with other LPXTG surface proteins, which are processed by sortases upon specific recognition of a highly conserved LPXTG motif. Bioinformatic analysis of all predicted LPXTG proteins encoded by the L. rhamnosus GG genome revealed a remarkable conservation of glycine residues juxtaposed to the canonical LPXTG motif. Here, we investigated and defined the role of this so-called triple glycine (TG) motif in determining sortase specificity during the pilus assembly and anchoring. Mutagenesis of the TG motif resulted in a lack or an alteration of the L. rhamnosus GG pilus structures, indicating that the TG motif is critical in pilus assembly and that they govern the pilin-specific and housekeeping sortase specificity. This allowed us to propose a regulatory model of the L. rhamnosus GG pilus biogenesis. Remarkably, the TG motif was identified in multiple pilus gene clusters of other Gram-positive bacteria, suggesting that similar signaling mechanisms occur in other, mainly pathogenic, species. © 2014 by The American Society for Biochemistry and Molecular Biology, Inc.

  17. Specific Involvement of Pilus Type 2a in Biofilm Formation in Group B Streptococcus

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    Galeotti, Cesira L.; Berti, Francesco; Necchi, Francesca; Reguzzi, Valerio; Ghezzo, Claudia; Telford, John Laird; Grandi, Guido; Maione, Domenico

    2010-01-01

    Streptococcus agalactiae is the primary colonizer of the anogenital mucosa of up to 30% of healthy women and can infect newborns during delivery and cause severe sepsis and meningitis. Persistent colonization usually involves the formation of biofilm and increasing evidences indicate that in pathogenic streptococci biofilm formation is mediated by pili. Recently, we have characterized pili distribution and conservation in 289 GBS clinical isolates and we have shown that GBS has three pilus types, 1, 2a and 2b encoded by three corresponding pilus islands, and that each strain carries one or two islands. Here we have investigated the capacity of these strains to form biofilms. We have found that most of the biofilm-formers carry pilus 2a, and using insertion and deletion mutants we have confirmed that pilus type 2a, but not pilus types 1 and 2b, confers biofilm-forming phenotype. We also show that deletion of the major ancillary protein of type 2a did not impair biofilm formation while the inactivation of the other ancillary protein and of the backbone protein completely abolished this phenotype. Furthermore, antibodies raised against pilus components inhibited bacterial adherence to solid surfaces, offering new strategies to prevent GBS infection by targeting bacteria during their initial attachment to host epithelial cells. PMID:20169161

  18. Specific involvement of pilus type 2a in biofilm formation in group B Streptococcus.

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    Cira Daniela Rinaudo

    Full Text Available Streptococcus agalactiae is the primary colonizer of the anogenital mucosa of up to 30% of healthy women and can infect newborns during delivery and cause severe sepsis and meningitis. Persistent colonization usually involves the formation of biofilm and increasing evidences indicate that in pathogenic streptococci biofilm formation is mediated by pili. Recently, we have characterized pili distribution and conservation in 289 GBS clinical isolates and we have shown that GBS has three pilus types, 1, 2a and 2b encoded by three corresponding pilus islands, and that each strain carries one or two islands. Here we have investigated the capacity of these strains to form biofilms. We have found that most of the biofilm-formers carry pilus 2a, and using insertion and deletion mutants we have confirmed that pilus type 2a, but not pilus types 1 and 2b, confers biofilm-forming phenotype. We also show that deletion of the major ancillary protein of type 2a did not impair biofilm formation while the inactivation of the other ancillary protein and of the backbone protein completely abolished this phenotype. Furthermore, antibodies raised against pilus components inhibited bacterial adherence to solid surfaces, offering new strategies to prevent GBS infection by targeting bacteria during their initial attachment to host epithelial cells.

  19. Effects of tcpB Mutations on Biogenesis and Function of the Toxin-Coregulated Pilus, the Type IVb Pilus of Vibrio cholerae.

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    Gao, Yang; Hauke, Caitlyn A; Marles, Jarrad M; Taylor, Ronald K

    2016-10-15

    Vibrio cholerae is the etiological agent of the acute intestinal disorder cholera. The toxin-coregulated pilus (TCP), a type IVb pilus, is an essential virulence factor of V. cholerae Recent work has shown that TcpB is a large minor pilin encoded within the tcp operon. TcpB contributes to efficient pilus formation and is essential for all TCP functions. Here, we have initiated a detailed targeted mutagenesis approach to further characterize this salient TCP component. We have identified (thus far) 20 residues of TcpB which affect either the steady-state level of TcpB or alter one or more TCP functions. This study provides a solid framework for further understanding of the complex role of TcpB and will be of use upon determination of the crystal structure of TcpB or related minor pilin orthologs of type IVb pilus systems. Type IV pili, such as the toxin-coregulated pilus (TCP) in V. cholerae, are bacterial appendages that often act as essential virulence factors. Minor pilins, like TcpB, of these pili systems often play integral roles in pilus assembly and function. In this study, we have generated mutations in tcpB to determine residues of importance for TCP stability and function. Combined with a predicted tertiary structure, characterization of these mutants allows us to better understand critical residues in TcpB and the role they may play in the mechanisms underlying minor pilin functions. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

  20. Regulation of PI-2b Pilus Expression in Hypervirulent Streptococcus agalactiae ST-17 BM110

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    du Merle, Laurence; Rosinski-Chupin, Isabelle; Gominet, Myriam; Bellais, Samuel; Poyart, Claire; Trieu-Cuot, Patrick

    2017-01-01

    The widely spread Streptococcus agalactiae (also known as Group B Streptococcus, GBS) “hypervirulent” ST17 clone is strongly associated with neonatal meningitis. The PI-2b locus is mainly found in ST17 strains but is also present in a few non ST17 human isolates such as the ST-7 prototype strain A909. Here, we analysed the expression of the PI-2b pilus in the ST17 strain BM110 as compared to the non ST17 A909. Comparative genome analyses revealed the presence of a 43-base pair (bp) hairpin-like structure in the upstream region of PI-2b operon in all 26 ST17 genomes, which was absent in the 8 non-ST17 strains carrying the PI-2b locus. Deletion of this 43-bp sequence in strain BM110 resulted in a 3- to 5-fold increased transcription of PI-2b. Characterization of PI-2b promoter region in A909 and BM110 strains was carried out by RNAseq, primer extension, qRT-PCR and transcriptional fusions with gfp as reporter gene. Our results indicate the presence of a single promoter (Ppi2b) with a transcriptional start site (TSS) mapped 37 bases upstream of the start codon of the first PI-2b gene. The large operon of 16 genes located upstream of PI-2b codes for the group B carbohydrate (also known as antigen B), a major constituent of the bacterial cell wall. We showed that the hairpin sequence located between antigen B and PI-2b operons is a transcriptional terminator. In A909, increased expression of PI-2b probably results from read-through transcription from antigen B operon. In addition, we showed that an extended 5’ promoter region is required for maximal transcription of gfp as a reporter gene in S. agalactiae from Ppi2b promoter. Gene reporter assays performed in Lactococcus lactis strain NZ9000, a related non-pathogenic Gram-positive species, revealed that GBS-specific regulatory factors are required to drive PI-2b transcription. PI-2b expression is up-regulated in the BM110ΔcovR mutant as compared to the parental BM110 strain, but this effect is probably indirect

  1. The Vibrio cholerae Minor Pilin TcpB Initiates Assembly and Retraction of the Toxin-Coregulated Pilus

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    Harn, Tony; Spielman, Ingrid; Gao, Yang; Kovacikova, Gabriela; Biais, Nicolas

    2016-01-01

    Type IV pilus (T4P) systems are complex molecular machines that polymerize major pilin proteins into thin filaments displayed on bacterial surfaces. Pilus functions require rapid extension and depolymerization of the pilus, powered by the assembly and retraction ATPases, respectively. A set of low abundance minor pilins influences pilus dynamics by unknown mechanisms. The Vibrio cholerae toxin-coregulated pilus (TCP) is among the simplest of the T4P systems, having a single minor pilin TcpB and lacking a retraction ATPase. Here we show that TcpB, like its homolog CofB, initiates pilus assembly. TcpB co-localizes with the pili but at extremely low levels, equivalent to one subunit per pilus. We used a micropillars assay to demonstrate that TCP are retractile despite the absence of a retraction ATPase, and that retraction relies on TcpB, as a V. cholerae tcpB Glu5Val mutant is fully piliated but does not induce micropillars movements. This mutant is impaired in TCP-mediated autoagglutination and TcpF secretion, consistent with retraction being required for these functions. We propose that TcpB initiates pilus retraction by incorporating into the growing pilus in a Glu5-dependent manner, which stalls assembly and triggers processive disassembly. These results provide a framework for understanding filament dynamics in more complex T4P systems and the closely related Type II secretion system. PMID:27992883

  2. The Vibrio cholerae Minor Pilin TcpB Initiates Assembly and Retraction of the Toxin-Coregulated Pilus.

    Directory of Open Access Journals (Sweden)

    Dixon Ng

    2016-12-01

    Full Text Available Type IV pilus (T4P systems are complex molecular machines that polymerize major pilin proteins into thin filaments displayed on bacterial surfaces. Pilus functions require rapid extension and depolymerization of the pilus, powered by the assembly and retraction ATPases, respectively. A set of low abundance minor pilins influences pilus dynamics by unknown mechanisms. The Vibrio cholerae toxin-coregulated pilus (TCP is among the simplest of the T4P systems, having a single minor pilin TcpB and lacking a retraction ATPase. Here we show that TcpB, like its homolog CofB, initiates pilus assembly. TcpB co-localizes with the pili but at extremely low levels, equivalent to one subunit per pilus. We used a micropillars assay to demonstrate that TCP are retractile despite the absence of a retraction ATPase, and that retraction relies on TcpB, as a V. cholerae tcpB Glu5Val mutant is fully piliated but does not induce micropillars movements. This mutant is impaired in TCP-mediated autoagglutination and TcpF secretion, consistent with retraction being required for these functions. We propose that TcpB initiates pilus retraction by incorporating into the growing pilus in a Glu5-dependent manner, which stalls assembly and triggers processive disassembly. These results provide a framework for understanding filament dynamics in more complex T4P systems and the closely related Type II secretion system.

  3. Type-IV Pilus Deformation Can Explain Retraction Behavior

    CERN Document Server

    Ghosh, Ranajay; Vaziri, Ashkan

    2014-01-01

    Polymeric filament like type IV Pilus (TFP) can transfer forces in excess of 100pN during their retraction before stalling, powering surface translocation(twitching). Single TFP level experiments have shown remarkable nonlinearity in the retraction behavior influenced by the external load as well as levels of PilT molecular motor protein. This includes reversal of motion near stall forces when the concentration of the PilT protein is lowered significantly. In order to explain this behavior, we analyze the coupling of TFP elasticity and interfacial behavior with PilT kinetics. We model retraction as reaction controlled and elongation as transport controlled process. The reaction rates vary with TFP deformation which is modeled as a compound elastic body consisting of multiple helical strands under axial load. Elongation is controlled by monomer transport which suffer entrapment due to excess PilT in the cell periplasm. Our analysis shows excellent agreement with a host of experimental observations and we prese...

  4. Structure and function of the adhesive type IV pilus of Sulfolobus acidocaldarius.

    Science.gov (United States)

    Henche, Anna-Lena; Ghosh, Abhrajyoti; Yu, Xiong; Jeske, Torsten; Egelman, Edward; Albers, Sonja-Verena

    2012-12-01

    Archaea display a variety of type IV pili on their surface and employ them in different physiological functions. In the crenarchaeon Sulfolobus acidocaldarius the most abundant surface structure is the aap pilus (archaeal adhesive pilus). The construction of in frame deletions of the aap genes revealed that all the five genes (aapA, aapX, aapE, aapF, aapB) are indispensible for assembly of the pilus and an impact on surface motility and biofilm formation was observed. Our analyses revealed that there exists a regulatory cross-talk between the expression of aap genes and archaella (formerly archaeal flagella) genes during different growth phases. The structure of the aap pilus is entirely different from the known bacterial type IV pili as well as other archaeal type IV pili. An aap pilus displayed 3 stranded helices where there is a rotation per subunit of ∼138° and a rise per subunit of ∼5.7 Å. The filaments have a diameter of ∼110 Å and the resolution was judged to be ∼9 Å. We concluded that small changes in sequence might be amplified by large changes in higher-order packing. Our finding of an extraordinary stability of aap pili possibly represents an adaptation to harsh environments that S. acidocaldarius encounters.

  5. Pilus biogenesis in Lactococcus lactis: molecular characterization and role in aggregation and biofilm formation.

    Directory of Open Access Journals (Sweden)

    Virginie Oxaran

    Full Text Available The genome of Lactococcus lactis strain IL1403 harbors a putative pilus biogenesis cluster consisting of a sortase C gene flanked by 3 LPxTG protein encoding genes (yhgD, yhgE, and yhhB, called here pil. However, pili were not detected under standard growth conditions. Over-expression of the pil operon resulted in production and display of pili on the surface of lactococci. Functional analysis of the pilus biogenesis machinery indicated that the pilus shaft is formed by oligomers of the YhgE pilin, that the pilus cap is formed by the YhgD pilin and that YhhB is the basal pilin allowing the tethering of the pilus fibers to the cell wall. Oligomerization of pilin subunits was catalyzed by sortase C while anchoring of pili to the cell wall was mediated by sortase A. Piliated L. lactis cells exhibited an auto-aggregation phenotype in liquid cultures, which was attributed to the polymerization of major pilin, YhgE. The piliated lactococci formed thicker, more aerial biofilms compared to those produced by non-piliated bacteria. This phenotype was attributed to oligomers of YhgE. This study provides the first dissection of the pilus biogenesis machinery in a non-pathogenic Gram-positive bacterium. Analysis of natural lactococci isolates from clinical and vegetal environments showed pili production under standard growth conditions. The identification of functional pili in lactococci suggests that the changes they promote in aggregation and biofilm formation may be important for the natural lifestyle as well as for applications in which these bacteria are used.

  6. Sortase A substrate specificity in GBS pilus 2a cell wall anchoring.

    Science.gov (United States)

    Necchi, Francesca; Nardi-Dei, Vincenzo; Biagini, Massimiliano; Assfalg, Michael; Nuccitelli, Annalisa; Cozzi, Roberta; Norais, Nathalie; Telford, John L; Rinaudo, C Daniela; Grandi, Guido; Maione, Domenico

    2011-01-01

    Streptococcus agalactiae, also referred to as Group B Streptococcus (GBS), is one of the most common causes of life-threatening bacterial infections in infants. In recent years cell surface pili have been identified in several Gram-positive bacteria, including GBS, as important virulence factors and promising vaccine candidates. In GBS, three structurally distinct types of pili have been discovered (pilus 1, 2a and 2b), whose structural subunits are assembled in high-molecular weight polymers by specific class C sortases. In addition, the highly conserved housekeeping sortase A (SrtA), whose main role is to link surface proteins to bacterial cell wall peptidoglycan by a transpeptidation reaction, is also involved in pili cell wall anchoring in many bacteria. Through in vivo mutagenesis, we demonstrate that the LPXTG sorting signal of the minor ancillary protein (AP2) is essential for pilus 2a anchoring. We successfully produced a highly purified recombinant SrtA (SrtA(ΔN40)) able to specifically hydrolyze the sorting signal of pilus 2a minor ancillary protein (AP2-2a) and catalyze in vitro the transpeptidation reaction between peptidoglycan analogues and the LPXTG motif, using both synthetic fluorescent peptides and recombinant proteins. By contrast, SrtA(ΔN40) does not catalyze the transpeptidation reaction with substrate-peptides mimicking sorting signals of the other pilus 2a subunits (the backbone protein and the major ancillary protein). Thus, our results add further insight into the proposed model of GBS pilus 2a assembly, in which SrtA is required for pili cell wall covalent attachment, acting exclusively on the minor accessory pilin, representing the terminal subunit located at the base of the pilus.

  7. Sortase A substrate specificity in GBS pilus 2a cell wall anchoring.

    Directory of Open Access Journals (Sweden)

    Francesca Necchi

    Full Text Available Streptococcus agalactiae, also referred to as Group B Streptococcus (GBS, is one of the most common causes of life-threatening bacterial infections in infants. In recent years cell surface pili have been identified in several Gram-positive bacteria, including GBS, as important virulence factors and promising vaccine candidates. In GBS, three structurally distinct types of pili have been discovered (pilus 1, 2a and 2b, whose structural subunits are assembled in high-molecular weight polymers by specific class C sortases. In addition, the highly conserved housekeeping sortase A (SrtA, whose main role is to link surface proteins to bacterial cell wall peptidoglycan by a transpeptidation reaction, is also involved in pili cell wall anchoring in many bacteria. Through in vivo mutagenesis, we demonstrate that the LPXTG sorting signal of the minor ancillary protein (AP2 is essential for pilus 2a anchoring. We successfully produced a highly purified recombinant SrtA (SrtA(ΔN40 able to specifically hydrolyze the sorting signal of pilus 2a minor ancillary protein (AP2-2a and catalyze in vitro the transpeptidation reaction between peptidoglycan analogues and the LPXTG motif, using both synthetic fluorescent peptides and recombinant proteins. By contrast, SrtA(ΔN40 does not catalyze the transpeptidation reaction with substrate-peptides mimicking sorting signals of the other pilus 2a subunits (the backbone protein and the major ancillary protein. Thus, our results add further insight into the proposed model of GBS pilus 2a assembly, in which SrtA is required for pili cell wall covalent attachment, acting exclusively on the minor accessory pilin, representing the terminal subunit located at the base of the pilus.

  8. Characterization of the SpaCBA pilus fibers in the probiotic Lactobacillus rhamnosus GG.

    Science.gov (United States)

    Reunanen, Justus; von Ossowski, Ingemar; Hendrickx, Antoni P A; Palva, Airi; de Vos, Willem M

    2012-04-01

    Lactobacillus rhamnosus GG is a human intestinal isolate that has been studied intensively because of its probiotic properties. We have previously shown that L. rhamnosus GG produces proteinaceous pili that earlier had been observed only in Gram-positive pathogens (M. Kankainen et al., Proc. Natl. Acad. Sci. U. S. A. 106:17193-17198, 2009). These pili were found to be encoded by the spaCBA gene cluster, and the pilus-associated SpaC pilin was shown to confer on the cells a mucus-binding ability. In addition to the spaCBA cluster, another putative pilus cluster, spaFED, was predicted from the L. rhamnosus GG genome sequence. Herein, we show that only SpaCBA pili are produced by L. rhamnosus, and we describe a detailed analysis of cell wall-associated and affinity-purified SpaCBA pili by Western blotting and immunogold electron microscopy. Our results indicate that SpaCBA pili are heterotrimeric protrusions with a SpaA subunit as the shaft-forming major pilin. Only a few SpaB subunits could be observed in pilus fibers. Instead, SpaB pilins were found at pilus bases, as assessed by immunogold double labeling of thin sections of cells, suggesting that SpaB is involved in the termination of pilus assembly. The SpaC adhesin was present along the whole pilus length at numbers nearly equaling those of SpaA. The relative amount and uniform distribution of SpaC within pili not only makes it possible to exert both long-distance and intimate contact with host tissue but also provides mucus-binding strength, which explains the prolonged intestinal residency times observed for L. rhamnosus GG compared to that of nonpiliated lactobacilli.

  9. Advances in F Pilus Research%F菌毛的研究进展

    Institute of Scientific and Technical Information of China (English)

    高荣凯

    2012-01-01

    F pilus is a kind of special structure on the surface of male E. Coli. It possesses important biological functions. The biology, structure and functions of F pilus were summarized in this paper, and the feasibility of application prospects in library-library screening were expected.%F菌毛是雄性大肠埃希菌表面的一种特殊结构,具有许多生物功能,就其分子生物学、结构和功能等方面的进展进行综述,并展望其应用于库-库筛选的可行性.

  10. Role and Regulation of the Flp/Tad Pilus in the Virulence of Pectobacterium atrosepticum SCRI1043 and Pectobacterium wasabiae SCC3193

    OpenAIRE

    Johanna Nykyri; Laura Mattinen; Outi Niemi; Satish Adhikari; Viia Kõiv; Panu Somervuo; Xin Fang; Petri Auvinen; Andres Mäe; E Tapio Palva; Minna Pirhonen

    2013-01-01

    In this study, we characterized a putative Flp/Tad pilus-encoding gene cluster, and we examined its regulation at the transcriptional level and its role in the virulence of potato pathogenic enterobacteria of the genus Pectobacterium. The Flp/Tad pilus-encoding gene clusters in Pectobacterium atrosepticum, Pectobacterium wasabiae and Pectobacterium aroidearum were compared to previously characterized flp/tad gene clusters, including that of the well-studied Flp/Tad pilus model organism Aggreg...

  11. Transformation competence and type-4 pilus biogenesis in Neisseria gonorrhoeae--a review.

    Science.gov (United States)

    Fussenegger, M; Rudel, T; Barten, R; Ryll, R; Meyer, T F

    1997-06-11

    In Neisseria gonorrhoea (Ngo), the processes of type-4 pilus biogenesis and DNA transformation are functionally linked and play a pivotal role in the life style of this strictly human pathogen. The assembly of pili from its main subunit pilin (PilE) is a prerequisite for gonococcal infection since it allows the first contact to epithelial cells in conjunction with the pilus tip-associated PilC protein. While the components of the pilus and its assembly machinery are either directly or indirectly involved in the transport of DNA across the outer membrane, other factors unrelated to pilus biogenesis appear to facilitate further DNA transfer across the murein layer (ComL, Tpc) and the inner membrane (ComA) before the transforming DNA is rescued in the recipient bacterial chromosome in a RecA-dependent manner. Interestingly, PilE is essential for the first step of transformation, i.e., DNA uptake, and is itself also subject to transformation-mediated phase and antigenic variation. This short-term adaptive mechanism allows Ngo to cope with changing micro-environments in the host as well as to escape the immune response during the course of infection. Given the fact that Ngo has no ecological niche other than man, horizontal genetic exchange is essential for a successful co-evolution with the host. Horizontal exchange gives rise to heterogeneous populations harboring clones which better withstand selective forces within the host. Such extended horizontal exchange is reflected by a high genome plasticity, the existence of mosaic genes and a low linkage disequilibrium of genetic loci within the neisserial population. This led to the concept that rather than regarding individual Neisseria species as independent traits, they comprise a collective of species interconnected via horizontal exchange and relying on a common gene pool.

  12. Genetic analysis and morphological identification of pilus-like structures in members of the genus Bifidobacterium

    LENUS (Irish Health Repository)

    2011-08-30

    Abstract Background Cell surface pili in Gram positive bacteria have been reported to orchestrate the colonization of host tissues, evasion of immunity and the development of biofilms. So far, little if any information is available on the presence of pilus-like structures in human gut commensals like bifidobacteria. Results and discussion In this report, Atomic Force Microscopy (AFM) of various bifidobacterial strains belonging to Bifidobacterium bifidum, Bifidobacterium longum subsp. longum, Bifidobacterium dentium, Bifidobacterium adolescentis and Bifidobacterium animalis subsp. lactis revealed the existence of appendages resembling pilus-like structures. Interestingly, these microorganisms harbour two to six predicted pilus gene clusters in their genome, with each organized in an operon encompassing the major pilin subunit-encoding gene (designated fimA or fimP) together with one or two minor pilin subunit-encoding genes (designated as fimB and\\/or fimQ), and a gene encoding a sortase enzyme (strA). Quantitative Real Time (qRT)-PCR analysis and RT-PCR experiments revealed a polycistronic mRNA, encompassing the fimA\\/P and fimB\\/Q genes, which are differentially expressed upon cultivation of bifidobacteria on various glycans.

  13. Structure and assembly of group B streptococcus pilus 2b backbone protein.

    Science.gov (United States)

    Cozzi, Roberta; Malito, Enrico; Lazzarin, Maddalena; Nuccitelli, Annalisa; Castagnetti, Andrea; Bottomley, Matthew J; Margarit, Immaculada; Maione, Domenico; Rinaudo, C Daniela

    2015-01-01

    Group B Streptococcus (GBS) is a major cause of invasive disease in infants. Like other Gram-positive bacteria, GBS uses a sortase C-catalyzed transpeptidation mechanism to generate cell surface pili from backbone and ancillary pilin precursor substrates. The three pilus types identified in GBS contain structural subunits that are highly immunogenic and are promising candidates for the development of a broadly-protective vaccine. Here we report the X-ray crystal structure of the backbone protein of pilus 2b (BP-2b) at 1.06Å resolution. The structure reveals a classical IgG-like fold typical of the pilin subunits of other Gram-positive bacteria. The crystallized portion of the protein (residues 185-468) encompasses domains D2 and D3 that together confer high stability to the protein due to the presence of an internal isopeptide bond within each domain. The D2+D3 region, lacking the N-terminal D1 domain, was as potent as the entire protein in conferring protection against GBS challenge in a well-established mouse model. By site-directed mutagenesis and complementation studies in GBS knock-out strains we identified the residues and motives essential for assembly of the BP-2b monomers into high-molecular weight complexes, thus providing new insights into pilus 2b polymerization.

  14. Structure and assembly of group B streptococcus pilus 2b backbone protein.

    Directory of Open Access Journals (Sweden)

    Roberta Cozzi

    Full Text Available Group B Streptococcus (GBS is a major cause of invasive disease in infants. Like other Gram-positive bacteria, GBS uses a sortase C-catalyzed transpeptidation mechanism to generate cell surface pili from backbone and ancillary pilin precursor substrates. The three pilus types identified in GBS contain structural subunits that are highly immunogenic and are promising candidates for the development of a broadly-protective vaccine. Here we report the X-ray crystal structure of the backbone protein of pilus 2b (BP-2b at 1.06Å resolution. The structure reveals a classical IgG-like fold typical of the pilin subunits of other Gram-positive bacteria. The crystallized portion of the protein (residues 185-468 encompasses domains D2 and D3 that together confer high stability to the protein due to the presence of an internal isopeptide bond within each domain. The D2+D3 region, lacking the N-terminal D1 domain, was as potent as the entire protein in conferring protection against GBS challenge in a well-established mouse model. By site-directed mutagenesis and complementation studies in GBS knock-out strains we identified the residues and motives essential for assembly of the BP-2b monomers into high-molecular weight complexes, thus providing new insights into pilus 2b polymerization.

  15. Crystal Structure of the Minor Pilin CofB, the Initiator of CFA/III Pilus Assembly in Enterotoxigenic Escherichia coli.

    Science.gov (United States)

    Kolappan, Subramania; Ng, Dixon; Yang, Guixiang; Harn, Tony; Craig, Lisa

    2015-10-23

    Type IV pili are extracellular polymers of the major pilin subunit. These subunits are held together in the pilus filament by hydrophobic interactions among their N-terminal α-helices, which also anchor the pilin subunits in the inner membrane prior to pilus assembly. Type IV pilus assembly involves a conserved group of proteins that span the envelope of Gram-negative bacteria. Among these is a set of minor pilins, so named because they share their hydrophobic N-terminal polymerization/membrane anchor segment with the major pilins but are much less abundant. Minor pilins influence pilus assembly and retraction, but their precise functions are not well defined. The Type IV pilus systems of enterotoxigenic Escherichia coli and Vibrio cholerae are among the simplest of Type IV pilus systems and possess only a single minor pilin. Here we show that the enterotoxigenic E. coli minor pilins CofB and LngB are required for assembly of their respective Type IV pili, CFA/III and Longus. Low levels of the minor pilins are optimal for pilus assembly, and CofB can be detected in the pilus fraction. We solved the 2.0 Å crystal structure of N-terminally truncated CofB, revealing a pilin-like protein with an extended C-terminal region composed of two discrete domains connected by flexible linkers. The C-terminal region is required for CofB to initiate pilus assembly. We propose a model for CofB-initiated pilus assembly with implications for understanding filament growth in more complex Type IV pilus systems as well as the related Type II secretion system. © 2015 by The American Society for Biochemistry and Molecular Biology, Inc.

  16. The Escherichia coli P and Type 1 Pilus Assembly Chaperones PapD and FimC Are Monomeric in Solution

    Energy Technology Data Exchange (ETDEWEB)

    Sarowar, Samema; Hu, Olivia J.; Werneburg, Glenn T.; Thanassi, David G.; Li, Huilin; Christie, P. J.

    2016-06-27

    ABSTRACT

    The chaperone/usher pathway is used by Gram-negative bacteria to assemble adhesive surface structures known as pili or fimbriae. Uropathogenic strains ofEscherichia coliuse this pathway to assemble P and type 1 pili, which facilitate colonization of the kidney and bladder, respectively. Pilus assembly requires a periplasmic chaperone and outer membrane protein termed the usher. The chaperone allows folding of pilus subunits and escorts the subunits to the usher for polymerization into pili and secretion to the cell surface. Based on previous structures of mutant versions of the P pilus chaperone PapD, it was suggested that the chaperone dimerizes in the periplasm as a self-capping mechanism. Such dimerization is counterintuitive because the chaperone G1 strand, important for chaperone-subunit interaction, is buried at the dimer interface. Here, we show that the wild-type PapD chaperone also forms a dimer in the crystal lattice; however, the dimer interface is different from the previously solved structures. In contrast to the crystal structures, we found that both PapD and the type 1 pilus chaperone, FimC, are monomeric in solution. Our findings indicate that pilus chaperones do not sequester their G1 β-strand by forming a dimer. Instead, the chaperones may expose their G1 strand for facile interaction with pilus subunits. We also found that the type 1 pilus adhesin, FimH, is flexible in solution while in complex with its chaperone, whereas the P pilus adhesin, PapGII, is rigid. Our study clarifies a crucial step in pilus biogenesis and reveals pilus-specific differences that may relate to biological function.

    IMPORTANCEPili are critical virulence factors for many bacterial pathogens. UropathogenicE. colirelies on P and type 1 pili assembled by the chaperone/usher pathway to

  17. Attenuation of the Type IV Pilus Retraction Motor Influences Neisseria gonorrhoeae Social and Infection Behavior

    Science.gov (United States)

    Hutchens, Danielle M.; Agellon, Al

    2016-01-01

    ABSTRACT Retraction of the type IV pilus (Tfp) mediates DNA uptake, motility, and social and infection behavior in a wide variety of prokaryotes. To date, investigations into Tfp retraction-dependent activities have used a mutant deleted of PilT, the ATPase motor protein that causes the pilus fiber to retract. ΔpilT cells are nontransformable, nonmotile, and cannot aggregate into microcolonies. We tested the hypothesis that these retraction-dependent activities are sensitive to the strength of PilT enzymatic activity by using the pathogen Neisseria gonorrhoeae as a model. We constructed an N. gonorrhoeae mutant with an amino acid substitution in the PilT Walker B box (a substitution of cysteine for leucine at position 201, encoded by pilTL201C). Purified PilTL201C forms a native hexamer, but mutant hexamers hydrolyze ATP at half the maximal rate. N. gonorrhoeae pilTL201C cells produce Tfp fibers, crawl at the same speed as the wild-type (wt) parent, and are equally transformable. However, the social behavior of pilTL201C cells is intermediate between the behaviors of wt and ΔpilT cells. The infection behavior of pilTL201C is also defective, due to its failure to activate the epidermal growth factor receptor (EGFR)-heparin-binding EGF-like growth factor (HB-EGF) pathway. Our study indicates that pilus retraction, per se, is not sufficient for N. gonorrhoeae microcolony formation or infectivity; rather, these activities are sensitive to the strength of PilT enzymatic activity. We discuss the implications of these findings for Neisseria pathogenesis in the context of mechanobiology. PMID:27923924

  18. Genetic analysis of the regulation of type IV pilus function by the Chp chemosensory system of Pseudomonas aeruginosa.

    Science.gov (United States)

    Bertrand, Jacob J; West, Joyce T; Engel, Joanne N

    2010-02-01

    The virulence of the opportunistic pathogen Pseudomonas aeruginosa involves the coordinate expression of many virulence factors, including type IV pili, which are required for colonization of host tissues and for twitching motility. Type IV pilus function is controlled in part by the Chp chemosensory system, which includes a histidine kinase, ChpA, and two CheY-like response regulators, PilG and PilH. How the Chp components interface with the type IV pilus motor proteins PilB, PilT, and PilU is unknown. We present genetic evidence confirming the role of ChpA, PilG, and PilB in the regulation of pilus extension and the role of PilH and PilT in regulating pilus retraction. Using informative double and triple mutants, we show that (i) ChpA, PilG, and PilB function upstream of PilH, PilT, and PilU; (ii) that PilH enhances PilT function; and (iii) that PilT and PilB retain some activity in the absence of signaling input from components of the Chp system. By site-directed mutagenesis, we demonstrate that the histidine kinase domain of ChpA and the phosphoacceptor sites of both PilG and PilH are required for type IV pilus function, suggesting that they form a phosphorelay system important in the regulation of pilus extension and retraction. Finally, we present evidence suggesting that pilA transcription is regulated by intracellular PilA levels. We show that PilA is a negative regulator of pilA transcription in P. aeruginosa and that the Chp system functionally regulates pilA transcription by controlling PilA import and export.

  19. Sortase activity is controlled by a flexible lid in the pilus biogenesis mechanism of gram-positive pathogens.

    Science.gov (United States)

    Manzano, Clothilde; Izoré, Thierry; Job, Viviana; Di Guilmi, Anne Marie; Dessen, Andréa

    2009-11-10

    Pili are surface-linked virulence factors that play key roles in infection establishment in a variety of pathogenic species. In Gram-positive pathogens, pilus formation requires the action of sortases, dedicated transpeptidases that covalently associate pilus building blocks. In Streptococcus pneumoniae, a major human pathogen, all genes required for pilus formation are harbored in a single pathogenicity islet which encodes three structural proteins (RrgA, RrgB, RrgC) and three sortases (SrtC-1, SrtC-2, SrtC-3). RrgB forms the backbone of the streptococcal pilus, to which minor pilins RrgA and RrgC are covalently associated. SrtC-1 is the main sortase involved in polymerization of the RrgB fiber and displays a lid which encapsulates the active site, a feature present in all pilus-related sortases. In this work, we show that catalysis by SrtC-1 proceeds through a catalytic triad constituted of His, Arg, and Cys and that lid instability affects protein fold and catalysis. In addition, we show by thermal shift analysis that lid flexibility can be stabilized by the addition of substrate-like peptides, a feature shared by other periplasmic transpeptidases. We also report the characterization of a trapped acyl-enzyme intermediate formed between SrtC-1 and RrgB. The presence of lid-encapsulated sortases in the pilus biogenesis systems in many Gram-positive pathogens points to a common mechanism of substrate recognition and catalysis that should be taken into consideration in the development of sortase inhibitors.

  20. Nucleotide sequence analysis of hypervariable junctions of Haemophilus influenzae pilus gene clusters.

    Science.gov (United States)

    Read, T D; Satola, S W; Farley, M M

    2000-12-01

    Haemophilus influenzae pili are surface structures that promote attachment to human epithelial cells. The five genes that encode pili, hifABCDE, are found inserted in genomes either between pmbA and hpt (hif-1) or between purE and pepN (hif-2). We determined the sequence between the ends of the pilus clusters and bordering genes in a number of H. influenzae strains. The junctions of the hif-1 cluster (limited to biogroup aegyptius isolates) are structurally simple. In contrast, hif-2 junctions are highly diverse, complex assemblies of conserved intergenic sequences (including genes hicA and hicB) with evidence of frequent recombination. Variation at hif-2 junctions seems to be tied to multiple copies of a 23-bp Haemophilus intergenic dyad sequence. The hif-1 cluster appears to have originated in biogroup aegyptius strains from invasion of the hpt-pmbA region by a DNA template containing the hif-2 genes with termini in the hairpin loop of flanking intergenic dyad sequences. The pilus gene clusters are an interesting model of a mobile "pathogenicity island" not associated with a phage, transposon, or insertion element.

  1. Structural model for covalent adhesion of the Streptococcus pyogenes pilus through a thioester bond.

    Science.gov (United States)

    Linke-Winnebeck, Christian; Paterson, Neil G; Young, Paul G; Middleditch, Martin J; Greenwood, David R; Witte, Gregor; Baker, Edward N

    2014-01-03

    The human pathogen Streptococcus pyogenes produces pili that are essential for adhesion to host surface receptors. Cpa, the adhesin at the pilus tip, was recently shown to have a thioester-containing domain. The thioester bond is believed to be important in adhesion, implying a mechanism of covalent attachment analogous to that used by human complement factors. Here, we have characterized a second active thioester-containing domain on Cpa, the N-terminal domain of Cpa (CpaN). Expression of CpaN in Escherichia coli gave covalently linked dimers. These were shown by x-ray crystallography and mass spectrometry to comprise two CpaN molecules cross-linked by the polyamine spermidine following reaction with the thioester bonds. This cross-linked CpaN dimer provides a model for the covalent attachment of Cpa to target receptors and thus the streptococcal pilus to host cells. Similar thioester domains were identified in cell wall proteins of other Gram-positive pathogens, suggesting that thioester domains are more widely used and provide a mechanism of adhesion by covalent bonding to target molecules on host cells that mimics that used by the human complement system to eliminate pathogens.

  2. Neisseria cinerea isolates can adhere to human epithelial cells by type IV pilus-independent mechanisms.

    Science.gov (United States)

    Wörmann, Mirka E; Horien, Corey L; Johnson, Errin; Liu, Guangyu; Aho, Ellen; Tang, Christoph M; Exley, Rachel M

    2016-03-01

    In pathogenic Neisseria species the type IV pili (Tfp) are of primary importance in host-pathogen interactions. Tfp mediate initial bacterial attachment to cell surfaces and formation of microcolonies via pilus-pilus interactions. Based on genome analysis, many non-pathogenic Neisseria species are predicted to express Tfp, but aside from studies on Neisseria elongata, relatively little is known about the formation and function of pili in these organisms. Here, we have analysed pilin expression and the role of Tfp in Neisseria cinerea. This non-pathogenic species shares a close taxonomic relationship to the pathogen Neisseria meningitidis and also colonizes the human oropharyngeal cavity. Through analysis of non-pathogenic Neisseria genomes we identified two genes with homology to pilE, which encodes the major pilin of N. meningitidis. We show which of the two genes is required for Tfp expression in N. cinerea and that Tfp in this species are required for DNA competence, similar to other Neisseria. However, in contrast to the meningococcus, deletion of the pilin gene did not impact the association of N. cinerea to human epithelial cells, demonstrating that N. cinerea isolates can adhere to human epithelial cells by Tfp-independent mechanisms.

  3. Characterisation and quantitation of pilus antigens of Moraxella bovis by ELISA.

    Science.gov (United States)

    Lepper, A W; Hermans, L R

    1986-12-01

    Hyperimmune serums raised in rabbits to purified pili from 9 Australian and 2 American strains of Moraxella bovis from infectious bovine keratoconjunctivitis (IBK) affected herds were used to study the degree of binding between combinations of antigen and antiserum in a conventional enzyme linked immunosorbent assay (ELISA). With the aid of appropriate absorption tests major antigenic differences among pili were found permitting 6 distinct serogroups to be recognised. Further, production of specific antiserums to representative strains of each serogroup in goats facilitated the development of a double antibody sandwich ELISA which could be used to quantitate pilus expression of a given strain of M. bovis, or to differentiate pilus serogroups of 22 strains of M. bovis obtained from a total of 12 Australian herds. Most isolates were found to belong to serogroups designated IV and V. One strain from the United States of America showed total homology with Australian serogroup IV while the other showed some cross-reactivity with serogroups V and VI.

  4. Structure of the Pseudomonas aeruginosa Type IVa Pilus Secretin at 7.4 Å.

    Science.gov (United States)

    Koo, Jason; Lamers, Ryan P; Rubinstein, John L; Burrows, Lori L; Howell, P Lynne

    2016-10-04

    Type IVa pili (T4aP) function as bacterial virulence factors. T4aP pass through the outer membranes of Gram-negative bacteria via homo-oligomeric secretins. We present a 7.4 Å cryoelectron microscopy structure of the Pseudomonas aeruginosa PilQ secretin. Peripheral and internal features show that the secretin is composed of 14 subunits with C7 symmetry. The channel is a ribbed cylinder with central peripheral spokes and a central gate closed on the periplasmic side. The structure suggests that during pilus extrusion, the central gate is displaced to the interior walls and that no additional conformational changes are required, as the internal diameter can accommodate the pilus. The N1 domain was resolved, while the N0 and the N-terminal β-domains proposed to bind peptidoglycan were absent in class average images and the final 3D map, indicating a high flexibility. These data provide the highest-resolution structure to date of a T4aP secretin.

  5. Insights into pilus assembly and secretion from the structure and functional characterization of usher PapC

    Energy Technology Data Exchange (ETDEWEB)

    Huang, Yihua; Smith, Barbara S.; Chen, Lucy X.; Baxter, Richard H.G.; Deisenhofer, Johann; UTSMC; Texas

    2009-07-10

    Ushers constitute a family of bacterial outer membrane proteins responsible for the assembly and secretion of surface organelles such as the pilus. The structure at 3.15-A resolution of the usher pyelonephritis-associated pili C (PapC) translocation domain reveals a 24-stranded kidney-shaped beta-barrel, occluded by an internal plug domain. The dimension of the pore allows tandem passage of individual folded pilus subunits in an upright pilus growth orientation, but is insufficient for accommodating donor strand exchange. The molecular packing revealed by the crystal structure shows that 2 PapC molecules in head-to-head orientation interact via exposed beta-strand edges, which could be the preferred dimer interaction in solution. In vitro reconstitution of fiber assemblies suggest that PapC monomers may be sufficient for fiber assembly and secretion; both the plug domain and the C-terminal domain of PapC are required for filament assembly, whereas the N-terminal domain is mainly responsible for recruiting the chaperone-subunit complexes to the usher. The plug domain has a dual function: gating the beta-pore and participating in pilus assembly.

  6. Structural Differences between the Streptococcus agalactiae Housekeeping and Pilus-Specific Sortases: SrtA and SrtC1

    Energy Technology Data Exchange (ETDEWEB)

    Khare, B.; Krishnan, V.; Rajashankar, K.R.; I-Hsiu, H.; Xin, M.; Ton-That, H.; Narayana, S.V. (Texas-HSC); (Cornell); (UAB)

    2011-10-21

    The assembly of pili on the cell wall of Gram-positive bacteria requires transpeptidase enzymes called sortases. In Streptococcus agalactiae, the PI-1 pilus island of strain 2603V/R encodes two pilus-specific sortases (SrtC1 and SrtC2) and three pilins (GBS80, GBS52 and GBS104). Although either pilus-specific sortase is sufficient for the polymerization of the major pilin, GBS80, incorporation of the minor pilins GBS52 and GBS104 into the pilus structure requires SrtC1 and SrtC2, respectively. The S. agalactiae housekeeping sortase, SrtA, whose gene is present at a different location and does not catalyze pilus polymerization, was shown to be involved in cell wall anchoring of pilus polymers. To understand the structural basis of sortases involved in such diverse functions, we determined the crystal structures of S. agalactiae SrtC1 and SrtA. Both enzymes are made of an eight-stranded beta-barrel core with variations in their active site architecture. SrtA exhibits a catalytic triad arrangement similar to that in Streptococcus pyogenes SrtA but different from that in Staphylococcus aureus SrtA. In contrast, the SrtC1 enzyme contains an N-terminal helical domain and a 'lid' in its putative active site, which is similar to that seen in Streptococcus pneumoniae pilus-specific sortases, although with subtle differences in positioning and composition. To understand the effect of such differences on substrate recognition, we have also determined the crystal structure of a SrtC1 mutant, in which the conserved DP(W/F/Y) motif was replaced with the sorting signal motif of GBS80, IPNTG. By comparing the structures of WT wild type SrtA and SrtC1 and the 'lid' mutant of SrtC1, we propose that structural elements within the active site and the lid may be important for defining the role of specific sortase in pili biogenesis.

  7. Copy number of pilus gene clusters in Haemophilus influenzae and variation in the hifE pilin gene.

    Science.gov (United States)

    Read, T D; Satola, S W; Opdyke, J A; Farley, M M

    1998-04-01

    Brazilian purpuric fever (BPF)-associated Haemophilus influenzae biogroup aegyptius strain F3031 contains two identical copies of a five gene cluster (hifA to hifE) encoding pili similar to well-characterized Hif fimbriae of H. influenzae type b. HifE, the putative pilus tip adhesin of F3031, shares only 40% amino acid sequence similarity with the same molecule from type b strains, whereas the other four proteins have 75 to 95% identity. To determine whether pilus cluster duplication and the hifE(F3031) allele were special features of BPF-associated bacteria, we analyzed a collection of H. influenzae strains by PCR with hifA- and hifE-specific oligonucleotides, by Southern hybridization with a hifC gene probe, and by nucleotide sequencing. The presence of two pilus clusters was limited to some H. influenzae biogroup aegyptius strains. The hifE(F3031) allele was limited to H. influenzae biogroup aegyptius. Two strains contained one copy of hifE(F3031) and one copy of a variant hifE allele. We determined the nucleotide sequences of four hifE genes from H. influenzae biogroup aegyptius and H. influenzae capsule serotypes a and c. The predicted proteins produced by these genes demonstrated only 35 to 70% identity to the three published HifE proteins from nontypeable H. influenzae, serotype b, and BPF strains. The C-terminal third of the molecules implicated in chaperone binding was the most highly conserved region. Three conserved domains in the otherwise highly variable N-terminal putative receptor-binding region of HifE were similar to conserved portions in the N terminus of Neisseria pilus adhesin PilC. We concluded that two pilus clusters and hifE(F3031) were not specific for BPF-causing H. influenzae, and we also identified portions of HifE possibly involved in binding mammalian cell receptors.

  8. Mechanistic stratification in electroactive biofilms of Geobacter sulfurreducens mediated by pilus nanowires

    Science.gov (United States)

    Steidl, Rebecca J.; Lampa-Pastirk, Sanela; Reguera, Gemma

    2016-08-01

    Electricity generation by Geobacter sulfurreducens biofilms grown on electrodes involves matrix-associated electron carriers, such as c-type cytochromes. Yet, the contribution of the biofilm's conductive pili remains uncertain, largely because pili-defective mutants also have cytochrome defects. Here we report that a pili-deficient mutant carrying an inactivating mutation in the pilus assembly motor PilB has no measurable defects in cytochrome expression, yet forms anode biofilms with reduced electroactivity and is unable to grow beyond a threshold distance (~10 μm) from the underlying electrode. The defects are similar to those of a Tyr3 mutant, which produces poorly conductive pili. The results support a model in which the conductive pili permeate the biofilms to wire the cells to the conductive biofilm matrix and the underlying electrode, operating coordinately with cytochromes until the biofilm reaches a threshold thickness that limits the efficiency of the cytochrome pathway but not the functioning of the conductive pili network.

  9. The Che4 pathway of Myxococcus xanthus regulates type IV pilus-mediated motility.

    Science.gov (United States)

    Vlamakis, Hera C; Kirby, John R; Zusman, David R

    2004-06-01

    Myxococcus xanthus co-ordinates cell movement during its complex life cycle using multiple chemotaxis-like signal transduction pathways. These pathways regulate both type IV pilus-mediated social (S) motility and adventurous (A) motility. During a search for new chemoreceptors, we identified the che4 operon, which encodes homologues to a MCP (methyl-accepting chemotaxis protein), two CheWs, a hybrid CheA-CheY, a response regulator and a CheR. Deletion of the che4 operon did not cause swarming or developmental defects in either the wild-type (A(+)S(+)) strain or in a strain sustaining only A motility (A(+)S(-)). However, in a strain displaying only S motility (A(-)S(+)), deletion of the che4 operon or the gene encoding the response regulator, cheY4, caused enhanced vegetative swarming and prevented aggregation and sporulation. In contrast, deletion of mcp4 caused reduced vegetative swarming and enhanced development compared with the parent strain. Single-cell analysis of the motility of the A(-)S(+) parent strain revealed a previously unknown inverse correlation between velocity and reversal frequency. Thus, cells that moved at higher velocities showed a reduced reversal frequency. This co-ordination of reversal frequency and velocity was lost in the mcp4 and cheY4 mutants. The structural components of the S motility apparatus were unaffected in the che4 mutants, suggesting that the Che4 system affects reversal frequency of cells by modulating the function of the type IV pilus.

  10. Conserved Streptococcus pneumoniae spirosomes suggest a single type of transformation pilus in competence.

    Directory of Open Access Journals (Sweden)

    Raphaël Laurenceau

    2015-04-01

    Full Text Available The success of S. pneumoniae as a major human pathogen is largely due to its remarkable genomic plasticity, allowing efficient escape from antimicrobials action and host immune response. Natural transformation, or the active uptake and chromosomal integration of exogenous DNA during the transitory differentiated state competence, is the main mechanism for horizontal gene transfer and genomic makeover in pneumococci. Although transforming DNA has been proposed to be captured by Type 4 pili (T4P in Gram-negative bacteria, and a competence-inducible comG operon encoding proteins homologous to T4P-biogenesis components is present in transformable Gram-positive bacteria, a prevailing hypothesis has been that S. pneumoniae assembles only short pseudopili to destabilize the cell wall for DNA entry. We recently identified a micrometer-sized T4P-like pilus on competent pneumococci, which likely serves as initial DNA receptor. A subsequent study, however, visualized a different structure--short, 'plaited' polymers--released in the medium of competent S. pneumoniae. Biochemical observation of concurrent pilin secretion led the authors to propose that the 'plaited' structures correspond to transformation pili acting as peptidoglycan drills that leave DNA entry pores upon secretion. Here we show that the 'plaited' filaments are not related to natural transformation as they are released by non-competent pneumococci, as well as by cells with disrupted pilus biogenesis components. Combining electron microscopy visualization with structural, biochemical and proteomic analyses, we further identify the 'plaited' polymers as spirosomes: macromolecular assemblies of the fermentative acetaldehyde-alcohol dehydrogenase enzyme AdhE that is well conserved in a broad range of Gram-positive and Gram-negative bacteria.

  11. Role and regulation of the Flp/Tad pilus in the virulence of Pectobacterium atrosepticum SCRI1043 and Pectobacterium wasabiae SCC3193.

    Directory of Open Access Journals (Sweden)

    Johanna Nykyri

    Full Text Available In this study, we characterized a putative Flp/Tad pilus-encoding gene cluster, and we examined its regulation at the transcriptional level and its role in the virulence of potato pathogenic enterobacteria of the genus Pectobacterium. The Flp/Tad pilus-encoding gene clusters in Pectobacterium atrosepticum, Pectobacterium wasabiae and Pectobacterium aroidearum were compared to previously characterized flp/tad gene clusters, including that of the well-studied Flp/Tad pilus model organism Aggregatibacter actinomycetemcomitans, in which this pilus is a major virulence determinant. Comparative analyses revealed substantial protein sequence similarity and open reading frame synteny between the previously characterized flp/tad gene clusters and the cluster in Pectobacterium, suggesting that the predicted flp/tad gene cluster in Pectobacterium encodes a Flp/Tad pilus-like structure. We detected genes for a novel two-component system adjacent to the flp/tad gene cluster in Pectobacterium, and mutant analysis demonstrated that this system has a positive effect on the transcription of selected Flp/Tad pilus biogenesis genes, suggesting that this response regulator regulate the flp/tad gene cluster. Mutagenesis of either the predicted regulator gene or selected Flp/Tad pilus biogenesis genes had a significant impact on the maceration ability of the bacterial strains in potato tubers, indicating that the Flp/Tad pilus-encoding gene cluster represents a novel virulence determinant in Pectobacterium. Soft-rot enterobacteria in the genera Pectobacterium and Dickeya are of great agricultural importance, and an investigation of the virulence of these pathogens could facilitate improvements in agricultural practices, thus benefiting farmers, the potato industry and consumers.

  12. Role and regulation of the Flp/Tad pilus in the virulence of Pectobacterium atrosepticum SCRI1043 and Pectobacterium wasabiae SCC3193.

    Science.gov (United States)

    Nykyri, Johanna; Mattinen, Laura; Niemi, Outi; Adhikari, Satish; Kõiv, Viia; Somervuo, Panu; Fang, Xin; Auvinen, Petri; Mäe, Andres; Palva, E Tapio; Pirhonen, Minna

    2013-01-01

    In this study, we characterized a putative Flp/Tad pilus-encoding gene cluster, and we examined its regulation at the transcriptional level and its role in the virulence of potato pathogenic enterobacteria of the genus Pectobacterium. The Flp/Tad pilus-encoding gene clusters in Pectobacterium atrosepticum, Pectobacterium wasabiae and Pectobacterium aroidearum were compared to previously characterized flp/tad gene clusters, including that of the well-studied Flp/Tad pilus model organism Aggregatibacter actinomycetemcomitans, in which this pilus is a major virulence determinant. Comparative analyses revealed substantial protein sequence similarity and open reading frame synteny between the previously characterized flp/tad gene clusters and the cluster in Pectobacterium, suggesting that the predicted flp/tad gene cluster in Pectobacterium encodes a Flp/Tad pilus-like structure. We detected genes for a novel two-component system adjacent to the flp/tad gene cluster in Pectobacterium, and mutant analysis demonstrated that this system has a positive effect on the transcription of selected Flp/Tad pilus biogenesis genes, suggesting that this response regulator regulate the flp/tad gene cluster. Mutagenesis of either the predicted regulator gene or selected Flp/Tad pilus biogenesis genes had a significant impact on the maceration ability of the bacterial strains in potato tubers, indicating that the Flp/Tad pilus-encoding gene cluster represents a novel virulence determinant in Pectobacterium. Soft-rot enterobacteria in the genera Pectobacterium and Dickeya are of great agricultural importance, and an investigation of the virulence of these pathogens could facilitate improvements in agricultural practices, thus benefiting farmers, the potato industry and consumers.

  13. Genomic characterization of non-mucus-adherent derivatives of Lactobacillus rhamnosus GG reveals genes affecting pilus biogenesis.

    Science.gov (United States)

    Rasinkangas, Pia; Reunanen, Justus; Douillard, François P; Ritari, Jarmo; Uotinen, Virva; Palva, Airi; de Vos, Willem M

    2014-11-01

    Lactobacillus rhamnosus GG is one of the best-characterized lactic acid bacteria and can be considered a probiotic paradigm. Comparative and functional genome analysis showed that L. rhamnosus GG harbors a genomic island including the spaCBA-srtC1 gene cluster, encoding the cell surface-decorating host-interacting pili. Here, induced mutagenesis was used to study pilus biogenesis in L. rhamnosus GG. A combination of two powerful approaches, mutation selection and next-generation sequencing, was applied to L. rhamnosus GG for the selection of pilus-deficient mutants from an enriched population. The isolated mutants were first screened by immuno-dot blot analysis using antiserum against pilin proteins. Relevant mutants were selected, and the lack of pili was confirmed by immunoelectron microscopy. The pilosotype of 10 mutant strains was further characterized by analyzing pilin expression using Western blot, dot blot, and immunofluorescence methods. A mucus binding assay showed that the mutants did not adhere to porcine intestinal mucus. Comparative genome sequence analysis using the Illumina MiSeq platform allowed us to determine the nature of the mutations in the obtained pilus-deficient derivatives. Three major classes of mutants with unique genotypes were observed: class I, with mutations in the srtC1 gene; class II, with a deletion containing the spaCBA-srtC1 gene cluster; and class III, with mutations in the spaA gene. Only a limited number of collateral mutations were observed, and one of the pilus-deficient derivatives with a deficient srtC1 gene contained 24 other mutations. This strain, PB12, can be considered a candidate for human trials addressing the impact of the absence of pili.

  14. Toxin-coregulated pilus-loaded microparticles as a vaccine against Vibrio cholerae O139

    Institute of Scientific and Technical Information of China (English)

    杜艳; 贾文祥; 刘莉

    2004-01-01

    @@ The cholera epidemics is an important public health problem in many developing countries. Highly effective and preventive vaccines against cholera are under investigation as alternatives to the one available presently. Much of the vaccine research focuses on colonization factors. Colonization of a human by the Vibrio cholerae (V. cholerae Ol strain is mediated by toxin-coregulated pilus (TCP), 1 which was shown to play a role in the infant mouse cholera model and subsequently in human volunteers. 2 TCP-loaded vaccines could potentially provide cross-protection among experimental strains. Data have indicated that poly (D,L-lactide)-polyethylene glycol copolymer (PELA)microparticles loaded antigens were strongly immunogenic, 3 and that these microparticles served as an effective delivery system for a single dose of vaccine. 4Microparticle formulation could represent the next generation of vaccines, as they are highly effective at delivery of vaccines, thus requiring fewer doses. 5 We prepared PELA microparticles loaded with TCP for testing as a vaccine; their targeting distributions were identified and related immune responses were analyzed.

  15. Two flagellotropic phages and one pilus-specific phage active against Asticcacaulis biprosthecum.

    Science.gov (United States)

    Pate, J L; Petzold, S J; Umbreit, T H

    1979-04-15

    Three phages active against cells of Asticcacaulis biprosthecum attach to receptor sites located at the pole of the cell where pili, flagella, and holdfast are produced. Phage phiAcS2, a large phage with a prolate cylindrical head and flexible, noncontractile tail, attaches to flagella as well as to receptor sites at the pole of the cell. Attachment to flagella occurs at the region where head and tail of the phage are joined, leaving the distal end of the tail free for attachment to receptor sites at the cell surface. Phages phiAcM2 and phiAcM4, are identical in appearance to each other, possessing prolate cylindrical heads and flexible, noncontractile tails, and are smaller than phage phiAcS2. Phage phiAcM4, exhibits the same flagellotropic characteristic as described for phage phiAcS2, including the manner of attachment to flagella. Phage phiAcM2 has no affinity for flagella, but attaches by the distal end of the tail to pili and to receptor sites at the pole of the cell. Mechanical removal of flagella and pili protects against infection by all three phages. Studies with phage-resistant mutants and with KCN-treated cells suggest that pili are required for infection by both flagellotropic and pilus-specific phages.

  16. Eliana Machado, Locus Brasilis

    OpenAIRE

    Ramos, Domingo

    2013-01-01

    Locus Brasilis es un complejo libro de la poeta brasileña y trilingüe Eliana Machado, que actualmente radica en Europa y por primera vez publica en el Perú. El volumen, el segundo de la autora luego de Blanco en el blanco, que apareció en Sao Paulo, consta de tres partes bien definidas, que corresponden a los tres reinos de la naturaleza. En poesía esto se traslada al hombre con sus respectivos correlatos del animal como ser destructivo, pero también conciliador y hasta protector de un mundo ...

  17. Structure and activity of Streptococcus pyogenes SipA: a signal peptidase-like protein essential for pilus polymerisation.

    Science.gov (United States)

    Young, Paul G; Proft, Thomas; Harris, Paul W R; Brimble, Margaret A; Baker, Edward N

    2014-01-01

    The pili expressed on the surface of the human pathogen Streptococcus pyogenes play an important role in host cell attachment, colonisation and pathogenesis. These pili are built from two or three components, an adhesin subunit at the tip, a major pilin that forms a polymeric shaft, and a basal pilin that is attached to the cell wall. Assembly is carried out by specific sortase (cysteine transpeptidase) enzyme. These components are encoded in a small gene cluster within the S. pyogenes genome, often together with another protein, SipA, whose function is unknown. We show through functional assays, carried out by expressing the S. pyogenes pilus components in Lactococcus lactis, SipA from the clinically important M1T1 strain is essential for pilus assembly, and that SipA function is likely to be conserved in all S. pyogenes. From the crystal structure of SipA we confirm that SipA belongs to the family of bacterial signal peptidases (SPases), which process the signal-peptides of secreted proteins. In contrast to a previous arm-swapped SipA dimer, this present structure shows that its principal domain closely resembles the catalytic domain of SPases and has a very similar peptide-binding cleft, but it lacks the catalytic Ser and Lys residues characteristic of SPases. In SipA these are replaced by Asp and Gly residues, which play no part in activity. We propose that SipA functions by binding a key component at the bacterial cell surface, in a conformation that facilitates pilus assembly.

  18. Biological roles of nontypeable Haemophilus influenzae type IV pilus proteins encoded by the pil and com operons.

    Science.gov (United States)

    Carruthers, Michael D; Tracy, Erin N; Dickson, Amanda C; Ganser, Kara B; Munson, Robert S; Bakaletz, Lauren O

    2012-04-01

    We previously demonstrated that one or more products of the genes in the pil and com gene clusters of the opportunistic human respiratory pathogen nontypeable Haemophilus influenzae (NTHI) are required for type IV pilus (Tfp) biogenesis and function. Here, we have now demonstrated that the pilABCD and comABCDEF gene clusters are operons and that the product of each gene is essential for normal pilus function. Mutants with nonpolar deletions in each of the 10 pil and com genes had an adherence defect when primary human airway cells were used as the target. These mutants were also diminished in their ability to form a biofilm in vitro and, additionally, were deficient in natural transformation. Collectively, our data demonstrate that the product of each gene within these operons is required for the normal biogenesis and/or function of NTHI Tfp. Based on the similarity of PilA to other type IV pilins, we further predicted that the product of the pilA gene would be the major pilin subunit. Toward that end, we also demonstrated by immunogold labeling and mass spectrometry that PilA is indeed the majority type IV pilin protein expressed by NTHI. These new observations set the stage for experiments designed to dissect the function of each of the proteins encoded by genes within the pil and com gene clusters. The ability to characterize individual proteins with vital roles in NTHI colonization or pathogenesis has the potential to reduce the burden of NTHI-induced diseases through development of a Tfp-derived vaccine or a pilus-directed therapeutic.

  19. Genomic and Gene-Expression Comparisons among Phage-Resistant Type-IV Pilus Mutants of Pseudomonas syringae pathovar phaseolicola.

    Directory of Open Access Journals (Sweden)

    Mark Sistrom

    Full Text Available Pseudomonas syringae pv. phaseolicola (Pph is a significant bacterial pathogen of agricultural crops, and phage Φ6 and other members of the dsRNA virus family Cystoviridae undergo lytic (virulent infection of Pph, using the type IV pilus as the initial site of cellular attachment. Despite the popularity of Pph/phage Φ6 as a model system in evolutionary biology, Pph resistance to phage Φ6 remains poorly characterized. To investigate differences between phage Φ6 resistant Pph strains, we examined genomic and gene expression variation among three bacterial genotypes that differ in the number of type IV pili expressed per cell: ordinary (wild-type, non-piliated, and super-piliated. Genome sequencing of non-piliated and super-piliated Pph identified few mutations that separate these genotypes from wild type Pph--and none present in genes known to be directly involved in type IV pilus expression. Expression analysis revealed that 81.1% of gene ontology (GO terms up-regulated in the non-piliated strain were down-regulated in the super-piliated strain. This differential expression is particularly prevalent in genes associated with respiration--specifically genes in the tricarboxylic acid cycle (TCA cycle, aerobic respiration, and acetyl-CoA metabolism. The expression patterns of the TCA pathway appear to be generally up and down-regulated, in non-piliated and super-piliated Pph respectively. As pilus retraction is mediated by an ATP motor, loss of retraction ability might lead to a lower energy draw on the bacterial cell, leading to a different energy balance than wild type. The lower metabolic rate of the super-piliated strain is potentially a result of its loss of ability to retract.

  20. The Type IVa Pilus Machinery Is Recruited to Sites of Future Cell Division.

    Science.gov (United States)

    Carter, Tyson; Buensuceso, Ryan N C; Tammam, Stephanie; Lamers, Ryan P; Harvey, Hanjeong; Howell, P Lynne; Burrows, Lori L

    2017-01-31

    Type IVa pili (T4aP) are ubiquitous microbial appendages used for adherence, twitching motility, DNA uptake, and electron transfer. Many of these functions depend on dynamic assembly and disassembly of the pilus by a megadalton-sized, cell envelope-spanning protein complex located at the poles of rod-shaped bacteria. How the T4aP assembly complex becomes integrated into the cell envelope in the absence of dedicated peptidoglycan (PG) hydrolases is unknown. After ruling out the potential involvement of housekeeping PG hydrolases in the installation of the T4aP machinery in Pseudomonas aeruginosa, we discovered that key components of inner (PilMNOP) and outer (PilQ) membrane subcomplexes are recruited to future sites of cell division. Midcell recruitment of a fluorescently tagged alignment subcomplex component, mCherry-PilO, depended on PilQ secretin monomers-specifically, their N-terminal PG-binding AMIN domains. PilP, which connects PilO to PilQ, was required for recruitment, while PilM, which is structurally similar to divisome component FtsA, was not. Recruitment preceded secretin oligomerization in the outer membrane, as loss of the PilQ pilotin PilF had no effect on localization. These results were confirmed in cells chemically blocked for cell division prior to outer membrane invagination. The hub protein FimV and a component of the polar organelle coordinator complex-PocA-were independently required for midcell recruitment of PilO and PilQ. Together, these data suggest an integrated, energy-efficient strategy for the targeting and preinstallation-rather than retrofitting-of the T4aP system into nascent poles, without the need for dedicated PG-remodeling enzymes.

  1. The Type IVa Pilus Machinery Is Recruited to Sites of Future Cell Division

    Science.gov (United States)

    Carter, Tyson; Buensuceso, Ryan N. C.; Tammam, Stephanie; Lamers, Ryan P.; Harvey, Hanjeong

    2017-01-01

    ABSTRACT Type IVa pili (T4aP) are ubiquitous microbial appendages used for adherence, twitching motility, DNA uptake, and electron transfer. Many of these functions depend on dynamic assembly and disassembly of the pilus by a megadalton-sized, cell envelope-spanning protein complex located at the poles of rod-shaped bacteria. How the T4aP assembly complex becomes integrated into the cell envelope in the absence of dedicated peptidoglycan (PG) hydrolases is unknown. After ruling out the potential involvement of housekeeping PG hydrolases in the installation of the T4aP machinery in Pseudomonas aeruginosa, we discovered that key components of inner (PilMNOP) and outer (PilQ) membrane subcomplexes are recruited to future sites of cell division. Midcell recruitment of a fluorescently tagged alignment subcomplex component, mCherry-PilO, depended on PilQ secretin monomers—specifically, their N-terminal PG-binding AMIN domains. PilP, which connects PilO to PilQ, was required for recruitment, while PilM, which is structurally similar to divisome component FtsA, was not. Recruitment preceded secretin oligomerization in the outer membrane, as loss of the PilQ pilotin PilF had no effect on localization. These results were confirmed in cells chemically blocked for cell division prior to outer membrane invagination. The hub protein FimV and a component of the polar organelle coordinator complex—PocA—were independently required for midcell recruitment of PilO and PilQ. Together, these data suggest an integrated, energy-efficient strategy for the targeting and preinstallation—rather than retrofitting—of the T4aP system into nascent poles, without the need for dedicated PG-remodeling enzymes. PMID:28143978

  2. Evidence for the Sialylation of PilA, the PI-2a Pilus-Associated Adhesin of Streptococcus agalactiae Strain NEM316: e0138103

    National Research Council Canada - National Science Library

    Eric Morello; Adeline Mallet; Yoan Konto-Ghiorghi; Thibault Chaze; Michel-Yves Mistou; Giulia Oliva; Liliana Oliveira; Anne-Marie Di Guilmi; Patrick Trieu-Cuot; Shaynoor Dramsi

    2015-01-01

    .... We and others previously showed that the PI-2a pilus polymers, made of the backbone pilin PilB, the tip adhesin PilA and the cell wall anchor protein PilC, promote adhesion to host epithelia and biofilm formation...

  3. Evidence for the Sialylation of PilA, the PI-2a Pilus-Associated Adhesin of Streptococcus agalactiae Strain NEM316

    National Research Council Canada - National Science Library

    Morello, Eric; Mallet, Adeline; Konto-Ghiorghi, Yoan; Chaze, Thibault; Mistou, Michel-Yves; Oliva, Giulia; Oliveira, Liliana; Di Guilmi, Anne-Marie; Trieu-Cuot, Patrick; Dramsi, Shaynoor

    2015-01-01

    .... We and others previously showed that the PI-2a pilus polymers, made of the backbone pilin PilB, the tip adhesin PilA and the cell wall anchor protein PilC, promote adhesion to host epithelia and biofilm formation...

  4. Lactobacillus rhamnosus GG and its SpaC pilus adhesin modulate inflammatory responsiveness and TLR-related gene expression in the fetal human gut

    NARCIS (Netherlands)

    Ganguli, K.; Collado, M.C.; Rautava, J.; Lu, L.; Satokari, R.M.; Ossowski, von I.; Reunanen, J.; Vos, de W.M.; Palva, A.; Isolauri, E.; Salminen, S.; Walker, W.A.; Rautava, S.

    2015-01-01

    BACKGROUND: Bacterial contact in utero modulates fetal and neonatal immune responses. Maternal probiotic supplementation reduces the risk of immune-mediated disease in the infant. We investigated the immunomodulatory properties of live Lactobacillus rhamnosus GG and its SpaC pilus adhesin in human

  5. Lactobacillus rhamnosus GG and its SpaC pilus adhesin modulate inflammatory responsiveness and TLR-related gene expression in the fetal human gut

    NARCIS (Netherlands)

    Ganguli, K.; Collado, M.C.; Rautava, J.; Lu, L.; Satokari, R.M.; Ossowski, von I.; Reunanen, J.; Vos, de W.M.; Palva, A.; Isolauri, E.; Salminen, S.; Walker, W.A.; Rautava, S.

    2015-01-01

    BACKGROUND: Bacterial contact in utero modulates fetal and neonatal immune responses. Maternal probiotic supplementation reduces the risk of immune-mediated disease in the infant. We investigated the immunomodulatory properties of live Lactobacillus rhamnosus GG and its SpaC pilus adhesin in human f

  6. Expression and functional characterization of the Agrobacterium VirB2 amino acid substitution variants in T-pilus biogenesis, virulence, and transient transformation efficiency.

    Directory of Open Access Journals (Sweden)

    Hung-Yi Wu

    Full Text Available Agrobacterium tumefaciens is a phytopathogenic bacterium that causes crown gall disease by transferring transferred DNA (T-DNA into the plant genome. The translocation process is mediated by the type IV secretion system (T4SS consisting of the VirD4 coupling protein and 11 VirB proteins (VirB1 to VirB11. All VirB proteins are required for the production of T-pilus, which consists of processed VirB2 (T-pilin and VirB5 as major and minor subunits, respectively. VirB2 is an essential component of T4SS, but the roles of VirB2 and the assembled T-pilus in Agrobacterium virulence and the T-DNA transfer process remain unknown. Here, we generated 34 VirB2 amino acid substitution variants to study the functions of VirB2 involved in VirB2 stability, extracellular VirB2/T-pilus production and virulence of A. tumefaciens. From the capacity for extracellular VirB2 production (ExB2+ or ExB2- and tumorigenesis on tomato stems (Vir+ or Vir-, the mutants could be classified into three groups: ExB2-/Vir-, ExB2-/Vir+, and ExB2+/Vir+. We also confirmed by electron microscopy that five ExB2-/Vir+ mutants exhibited a wild-type level of virulence with their deficiency in T-pilus formation. Interestingly, although the five T-pilus-/Vir+ uncoupling mutants retained a wild-type level of tumorigenesis efficiency on tomato stems and/or potato tuber discs, their transient transformation efficiency in Arabidopsis seedlings was highly attenuated. In conclusion, we have provided evidence for a role of T-pilus in Agrobacterium transformation process and have identified the domains and amino acid residues critical for VirB2 stability, T-pilus biogenesis, tumorigenesis, and transient transformation efficiency.

  7. Pilus gene pool variation and the virulence of Corynebacterium diphtheriae clinical isolates during infection of a nematode.

    Science.gov (United States)

    Broadway, Melissa M; Rogers, Elizabeth A; Chang, Chungyu; Huang, I-Hsiu; Dwivedi, Prabhat; Yildirim, Suleyman; Schmitt, Michael P; Das, Asis; Ton-That, Hung

    2013-08-01

    Toxigenic Corynebacterium diphtheriae strains cause diphtheria in humans. The toxigenic C. diphtheriae isolate NCTC13129 produces three distinct heterotrimeric pili that contain SpaA, SpaD, and SpaH, making up the shaft structure. The SpaA pili are known to mediate bacterial adherence to pharyngeal epithelial cells. However, to date little is known about the expression of different pili in various clinical isolates and their importance in bacterial pathogenesis. Here, we characterized a large collection of C. diphtheriae clinical isolates for their pilin gene pool by PCR and for the expression of the respective pilins by immunoblotting with antibodies against Spa pilins. Consistent with the role of a virulence factor, the SpaA-type pili were found to be prevalent among the isolates, and most significantly, corynebacterial adherence to pharyngeal epithelial cells was strictly correlated with isolates that were positive for the SpaA pili. By comparison, the isolates were heterogeneous for the presence of SpaD- and SpaH-type pili. Importantly, using Caenorhabditis elegans as a model host for infection, we show here that strain NCTC13129 rapidly killed the nematodes, the phenotype similar to isolates that were positive for toxin and all pilus types. In contrast, isogenic mutants of NCTC13129 lacking SpaA-type pili or devoid of toxin and SpaA pili exhibited delayed killing of nematodes with similar kinetics. Consistently, nontoxigenic or toxigenic isolates that lack one, two, or all three pilus types were also attenuated in virulence. This work signifies the important role of pili in corynebacterial pathogenesis and provides a simple host model to identify additional virulence factors.

  8. Type IV pilus assembly proficiency and dynamics influence pilin subunit phospho-form macro- and microheterogeneity in Neisseria gonorrhoeae.

    Directory of Open Access Journals (Sweden)

    Åshild Vik

    Full Text Available The PilE pilin subunit protein of the gonococcal Type IV pilus (Tfp colonization factor undergoes multisite, covalent modification with the zwitterionic phospho-form modification phosphoethanolamine (PE. In a mutant lacking the pilin-like PilV protein however, PilE is modified with a mixture of PE and phosphocholine (PC. Moreover, intrastrain variation of PilE PC modification levels have been observed in backgrounds that constitutively express PptA (the protein phospho-form transferase A required for both PE and PC modification. The molecular basis underlying phospho-form microheterogeneity in these instances remains poorly defined. Here, we examined the effects of mutations at numerous loci that disrupt or perturb Tfp assembly and observed that these mutants phenocopy the pilV mutant vis a vis phospho-form modification status. Thus, PC modification appears to be directly or indirectly responsive to the efficacy of pilin subunit interactions. Despite the complexity of contributing factors identified here, the data favor a model in which increased retention in the inner membrane may act as a key signal in altering phospho-form modification. These results also provide an alternative explanation for the variation in PilE PC levels observed previously and that has been assumed to be due to phase variation of pptA. Moreover, mass spectrometry revealed evidence for mono- and di-methylated forms of PE attached to PilE in mutants deficient in pilus assembly, directly implicating a methyltransferase-based pathway for PC synthesis in N. gonorrhoeae.

  9. Coherent states and geodesics cut locus and conjugate locus

    CERN Document Server

    Berceanu, S

    1997-01-01

    The intimate relationship between coherent states and geodesics is pointed out. For homogenous manifolds on which the exponential from the Lie algebra to the Lie group equals the geodesic exponential, and in particular for symmetric spaces, it is proved that the cut locus of the point $0$ is equal to the set of coherent vectors orthogonal to $\\vert 0>$. A simple method to calculate the conjugate locus in Hermitian symmetric spaces with significance in the coherent state approach is presented. The results are illustrated on the complex Grassmann manifold.

  10. Structure of the cytoplasmic domain of TcpE, the inner membrane core protein required for assembly of the Vibrio cholerae toxin-coregulated pilus.

    Science.gov (United States)

    Kolappan, Subramaniapillai; Craig, Lisa

    2013-04-01

    Type IV pili are long thin surface-displayed polymers of the pilin subunit that are present in a diverse group of bacteria. These multifunctional filaments are critical to virulence for pathogens such as Vibrio cholerae, which use them to form microcolonies and to secrete the colonization factor TcpF. The type IV pili are assembled from pilin subunits by a complex inner membrane machinery. The core component of the type IV pilus-assembly platform is an integral inner membrane protein belonging to the GspF superfamily of secretion proteins. These proteins somehow convert chemical energy from ATP hydrolysis by an assembly ATPase on the cytoplasmic side of the inner membrane to mechanical energy for extrusion of the growing pilus filament out of the inner membrane. Most GspF-family inner membrane core proteins are predicted to have N-terminal and central cytoplasmic domains, cyto1 and cyto2, and three transmembrane segments, TM1, TM2 and TM3. Cyto2 and TM3 represent an internal repeat of cyto1 and TM1. Here, the 1.88 Å resolution crystal structure of the cyto1 domain of V. cholerae TcpE, which is required for assembly of the toxin-coregulated pilus, is reported. This domain folds as a monomeric six-helix bundle with a positively charged membrane-interaction face at one end and a hydrophobic groove at the other end that may serve as a binding site for partner proteins in the pilus-assembly complex.

  11. Crystallization and X-ray Crystallographic Analysis of the Adhesive SpaC Pilin Subunit in the SpaCBA Pilus of Gut-adapted Lactobacillus rhamnosus GG.

    Science.gov (United States)

    Kant, Abhiruchi; von Ossowski, Ingemar; Palva, Airi; Krishnan, Vengadesan

    2016-01-01

    Gram-positive Lactobacillus rhamnosus GG, a gut-adapted commensalic (and probiotic) strain, is known to express sortase-assembled pili on its cell surface. These SpaCBA-called pili consist of three different types of building blocks; the SpaA backbone-pilin subunit and the SpaB and SpaC ancillary pilins. SpaC is a relatively large (~90kDa) multi-domain fimbrial adhesin, and while it is located primarily at the SpaCBA pilus tip, occasionally, it can also be detected throughout the length of pilus backbone. Functionally, SpaC mainly accounts for SpaCBA pilus-mediated interactions with intestinal mucus, collagen, and human gut epithelial cells. Moreover, SpaC adhesiveness is also perceived to have a causal relationship with SpaCBA pilus-induced host-cell immune responses. In order to improve the mechanistic understanding of SpaC and its adhesive properties by structural investigation, we purified and successfully crystallized a recombinant construct of the near full-length SpaC protein (residues 36-856) in the presence of magnesium ions. X-ray diffraction data were collected to 2.6 Å resolution. The SpaC crystal belongs to the space group P21212 with unit cell parameters a = 116.5, b = 128.3, c = 136.5 Å and contains two molecules in the asymmetric unit. Presence of conserved metal ion-dependent adhesion site containing von Willebrand factor type A domain suggests its likely role in the function of SpaC.

  12. [Study on preferred retinal locus].

    Science.gov (United States)

    Dai, Bing-Fa; Hu, Jian-Min; Xu, Duan-Lian

    2012-03-01

    Preferred retinal locus (PRL) is always found in the age-related macular degeneration and other macular damages in patients with low vision, and it is a very important anatomic position in patients with central vision impairment to achieve the rehabilitation. In recent years, the training of preferred retinal locus (PRL) has become a research hotspot of low vision rehabilitation, it can clearly improve functional vision and quality of life. The authors reviewed relevant literatures, and summarized the definition, position, characteristics, training and clinical implications of the PRL.

  13. Lactobacillus rhamnosus GG and its SpaC pilus adhesin modulate inflammatory responsiveness and TLR-related gene expression in the fetal human gut

    Science.gov (United States)

    Ganguli, Kriston; Collado, Maria Carmen; Rautava, Jaana; Lu, Lei; Satokari, Reetta; von Ossowski, Ingemar; Reunanen, Justus; de Vos, Willem M.; Palva, Airi; Isolauri, Erika; Salminen, Seppo; Walker, W. Allan; Rautava, Samuli

    2015-01-01

    Background Bacterial contact in utero modulates fetal and neonatal immune responses. Maternal probiotic supplementation reduces the risk of immune-mediated disease in the infant. We investigated the immunomodulatory properties of live Lactobacillus rhamnosus GG and its SpaC pilus adhesin in human fetal intestinal models. Methods TNF-α mRNA expression was measured by qPCR in a human fetal intestinal organ culture model exposed to live L. rhamnosus GG and proinflammatory stimuli. Binding of recombinant SpaC pilus protein to intestinal epithelial cells was assessed in human fetal intestinal organ culture and the human fetal intestinal epithelial cell line H4 by immunohistochemistry and immunofluorescence, respectively. TLR-related gene expression in fetal ileal organ culture after exposure to recombinant SpaC was assessed by qPCR. Results Live L. rhamnosus GG significantly attenuates pathogen-induced TNF-α mRNA expression in the human fetal gut. Recombinant SpaC protein was found to adhere to the fetal gut and to modulate varying levels of TLR-related gene expression. Conclusion The human fetal gut is responsive to luminal microbes. L. rhamnosus GG significantly attenuates fetal intestinal inflammatory responses to pathogenic bacteria. The L. rhamnosus GG pilus adhesin SpaC binds to immature human intestinal epithelial cells and directly modulates intestinal epithelial cell innate immune gene expression. PMID:25580735

  14. Genetic Identification of a PilT Motor in Geobacter sulfurreducens Reveals a Role for Pilus Retraction in Extracellular Electron Transfer

    Science.gov (United States)

    Speers, Allison M.; Schindler, Bryan D.; Hwang, Jihwan; Genc, Aycin; Reguera, Gemma

    2016-01-01

    The metal-reducing bacterium Geobacter sulfurreducens requires the expression of conductive pili to reduce iron oxides and to wire electroactive biofilms, but the role of pilus retraction in these functions has remained elusive. Here we show that of the four PilT proteins encoded in the genome of G. sulfurreducens, PilT3 powered pilus retraction in planktonic cells of a PilT-deficient strain of P. aeruginosa and restored the dense mutant biofilms to wild-type levels. Furthermore, PilT3 and PilT4 rescued the twitching motility defect of the PilT-deficient mutant. However, PilT4 was the only paralog whose inactivation in G. sulfurreducens lead to phenotypes associated with the hyperpiliation of non-retractile mutants such as enhanced adhesion and biofilm-forming abilities. In addition, PilT4 was required to reduce iron oxides. Taken together, the results indicate that PilT4 is the motor ATPase of G. sulfurreducens pili and reveal a previously unrecognized role for pilus retraction in extracellular electron transfer, a strategy that confers on Geobacter spp. an adaptive advantage for metal reduction in the natural environment. PMID:27799920

  15. Isopeptide bonds of the major pilin protein BcpA influence pilus structure and bundle formation on the surface of Bacillus cereus

    Energy Technology Data Exchange (ETDEWEB)

    Hendrickx, Antoni P.A.; Poor, Catherine B.; Jureller, Justin E.; Budzik, Jonathan M.; He, Chuan; Schneewind, Olaf (UC)

    2012-09-05

    Bacillus cereus strains elaborate pili on their surface using a mechanism of sortase-mediated cross-linking of major and minor pilus components. Here we used a combination of electron microscopy and atomic force microscopy to visualize these structures. Pili occur as single, double or higher order assemblies of filaments formed from monomers of the major pilin, BcpA, capped by the minor pilin, BcpB. Previous studies demonstrated that within assembled pili, four domains of BcpA -- CNA{sub 1}, CNA{sub 2}, XNA and CNA{sub 3} -- each acquire intramolecular lysine-asparagine isopeptide bonds formed via catalytic glutamic acid or aspartic acid residues. Here we showed that mutants unable to form the intramolecular isopeptide bonds in the CNA2 or CNA3 domains retain the ability to form pilus bundles. A mutant lacking the CNA{sub 1} isopeptide bond assembled deformed pilin subunits that failed to associate as bundles. X-ray crystallography revealed that the BcpA variant Asp{sup 312}Ala, lacking an aspartyl catalyst, did not generate the isopeptide bond within the jelly-roll structure of XNA. The Asp{sup 312}Ala mutant was also unable to form bundles and promoted the assembly of deformed pili. Thus, structural integrity of the CNA{sub 1} and XNA domains are determinants for the association of pili into higher order bundle structures and determine native pilus structure.

  16. Genetic identification of a PilT motor in Geobacter sulfurreducens reveals a role for pilus retraction in extracellular electron transfer

    Directory of Open Access Journals (Sweden)

    Allison Speers

    2016-10-01

    Full Text Available The metal-reducing bacterium Geobacter sulfurreducens requires the expression of conductive pili to reduce iron oxides and to wire electroactive biofilms, but the role of pilus retraction in these functions has remained elusive. Here we show that of the four PilT proteins encoded in the genome of G. sulfurreducens, PilT3 powered pilus retraction in planktonic cells of a PilT-deficient strain of P. aeruginosa and restored the dense mutant biofilms to wild-type levels. Furthermore, PilT3 and PilT4 rescued the twitching motility defect of the PilT-deficient mutant. However, PilT4 was the only paralogue whose inactivation in G. sulfurreducens lead to phenotypes associated with the hyperpiliation of non-retractile mutants such as enhanced adhesion and biofilm-forming abilities. In addition, PilT4 was required to reduce iron oxides. Taken together, the results indicate that PilT4 is the motor ATPase of G. sulfurreducens pili and reveal a previously unrecognized role for pilus retraction in extracellular electron transfer, a strategy that confers on Geobacter spp. an adaptive advantage for metal reduction in the natural environment.

  17. Purification, crystallization and preliminary X-ray diffraction analysis of the Escherichia coli common pilus chaperone EcpB

    Energy Technology Data Exchange (ETDEWEB)

    Garnett, James A.; Diallo, Mamou; Matthews, Steve J., E-mail: s.j.matthews@imperial.ac.uk [Imperial College London, South Kensington, London SW7 2AZ (United Kingdom)

    2015-05-20

    In Escherichia coli, the common pilus (Ecp) belongs to an alternative chaperone–usher pathway that plays a major role in both early biofilm formation and host-cell adhesion. Initial attempts at crystallizing the chaperone EcpB using natively purified protein from the bacterial periplasm were not successful; however, after the isolation of EcpB under denaturing conditions and subsequent refolding, crystals were obtained at pH 8.0 using the sitting-drop method of vapour diffusion. This is the first time that this refolding strategy has been used to purify CU chaperones. Pili are key cell-surface components that allow the attachment of bacteria to both biological and abiotic solid surfaces, whilst also mediating interactions between themselves. In Escherichia coli, the common pilus (Ecp) belongs to an alternative chaperone–usher (CU) pathway that plays a major role in both early biofilm formation and host-cell adhesion. The chaperone EcpB is involved in the biogenesis of the filament, which is composed of EcpA and EcpD. Initial attempts at crystallizing EcpB using natively purified protein from the bacterial periplasm were not successful; however, after the isolation of EcpB under denaturing conditions and subsequent refolding, crystals were obtained at pH 8.0 using the sitting-drop method of vapour diffusion. Diffraction data have been processed to 2.4 Å resolution. These crystals belonged to the trigonal space group P3{sub 1}21 or P3{sub 2}21, with unit-cell parameters a = b = 62.65, c = 121.14 Å and one monomer in the asymmetric unit. Molecular replacement was unsuccessful, but selenomethionine-substituted protein and heavy-atom derivatives are being prepared for phasing. The three-dimensional structure of EcpB will provide invaluable information on the subtle mechanistic differences in biogenesis between the alternative and classical CU pathways. Furthermore, this is the first time that this refolding strategy has been used to purify CU chaperones, and it

  18. Cloning-independent markerless gene editing in Streptococcus sanguinis: novel insights in type IV pilus biology.

    Science.gov (United States)

    Gurung, Ishwori; Berry, Jamie-Lee; Hall, Alexander M J; Pelicic, Vladimir

    2016-11-29

    Streptococcus sanguinis, a naturally competent opportunistic human pathogen, is a Gram-positive workhorse for genomics. It has recently emerged as a model for the study of type IV pili (Tfp)-exceptionally widespread and important prokaryotic filaments. To enhance genetic manipulation of Streptococcus sanguinis, we have developed a cloning-independent methodology, which uses a counterselectable marker and allows sophisticated markerless gene editing in situ We illustrate the utility of this methodology by answering several questions regarding Tfp biology by (i) deleting single or mutiple genes, (ii) altering specific bases in genes of interest, and (iii) engineering genes to encode proteins with appended affinity tags. We show that (i) the last six genes in the pil locus harbouring all the genes dedicated to Tfp biology play no role in piliation or Tfp-mediated motility, (ii) two highly conserved Asp residues are crucial for enzymatic activity of the prepilin peptidase PilD and (iii) that pilin subunits with a C-terminally appended hexa-histidine (6His) tag are still assembled into functional Tfp. The methodology for genetic manipulation we describe here should be broadly applicable.

  19. Locus of Control and Interpersonal Attraction.

    Science.gov (United States)

    Fagan, M. Michael

    1980-01-01

    The role of locus of control in interpersonal attraction was examined by administering 1) the Nowicki-Strickland Locus of Control Scale and 2) a sociometric test of friendship to 200 eighth graders. (CM)

  20. Intercellular adhesion molecule 1 serves as a primary cognate receptor for the Type IV pilus of nontypeable Haemophilus influenzae.

    Science.gov (United States)

    Novotny, Laura A; Bakaletz, Lauren O

    2016-08-01

    Nontypeable Haemophilus influenzae (NTHI) utilizes the Type IV pilus (Tfp) to adhere to respiratory tract epithelial cells thus colonizing its human host; however, the host cell receptor to which this adhesive protein binds is unknown. From a panel of receptors engaged by Tfp expressed by other bacterial species, we showed that the majority subunit of NTHI Tfp, PilA, bound to intercellular adhesion molecule 1 (ICAM1) and that this interaction was both specific and of high affinity. Further, Tfp-expressing NTHI inoculated on to polarized respiratory tract epithelial cells that expressed ICAM1 were significantly more adherent compared to Tfp-deficient NTHI or NTHI inoculated on to epithelial cells to which ICAM1 gene expression was silenced. Moreover, pre-incubation of epithelial cells with recombinant soluble PilA (rsPilA) blocked adherence of NTHI, an outcome that was abrogated by admixing rsPilA with ICAM1 prior to application on to the target cells. Epithelial cells infected with adenovirus or respiratory syncytial virus showed increased expression of ICAM1; this outcome supported augmented adherence of Tfp-expressing NTHI. Collectively, these data revealed the cognate receptor for NTHI Tfp as ICAM1 and promote continued development of a Tfp-targeted vaccine for NTHI-induced diseases of the airway wherein upper respiratory tract viruses play a key predisposing role.

  1. Speaking rate effects on locus equation slope

    Science.gov (United States)

    Berry, Jeff; Weismer, Gary

    2013-01-01

    A locus equation describes a 1st order regression fit to a scatter of vowel steady-state frequency values predicting vowel onset frequency values. Locus equation coefficients are often interpreted as indices of coarticulation. Speaking rate variations with a constant consonant–vowel form are thought to induce changes in the degree of coarticulation. In the current work, the hypothesis that locus slope is a transparent index of coarticulation is examined through the analysis of acoustic samples of large-scale, nearly continuous variations in speaking rate. Following the methodological conventions for locus equation derivation, data pooled across ten vowels yield locus equation slopes that are mostly consistent with the hypothesis that locus equations vary systematically with coarticulation. Comparable analyses between different four-vowel pools reveal variations in the locus slope range and changes in locus slope sensitivity to rate change. Analyses across rate but within vowels are substantially less consistent with the locus hypothesis. Taken together, these findings suggest that the practice of vowel pooling exerts a non-negligible influence on locus outcomes. Results are discussed within the context of articulatory accounts of locus equations and the effects of speaking rate change. PMID:24535890

  2. A slow-forming isopeptide bond in the structure of the major pilin SpaD from Corynebacterium diphtheriae has implications for pilus assembly

    Energy Technology Data Exchange (ETDEWEB)

    Kang, Hae Joo; Paterson, Neil G. [University of Auckland, Private Bag 92019, Auckland 1142 (New Zealand); Kim, Chae Un [Cornell University, Ithaca, NY 14853 (United States); Middleditch, Martin [University of Auckland, Private Bag 92019, Auckland 1142 (New Zealand); Chang, Chungyu; Ton-That, Hung [University of Texas–Houston Medical School, Houston, TX 77030 (United States); Baker, Edward N., E-mail: ted.baker@auckland.ac.nz [University of Auckland, Private Bag 92019, Auckland 1142 (New Zealand)

    2014-05-01

    Two crystal structures of the major pilin SpaD from C. diphtheriae have been determined at 1.87 and 2.5 Å resolution. The N-terminal domain is found to contain an isopeptide bond that forms slowly over time in the recombinant protein. Given its structural context, this provides insight into the relationship between internal isopeptide-bond formation and pilus assembly. The Gram-positive organism Corynebacterium diphtheriae, the cause of diphtheria in humans, expresses pili on its surface which it uses for adhesion and colonization of its host. These pili are covalent protein polymers composed of three types of pilin subunit that are assembled by specific sortase enzymes. A structural analysis of the major pilin SpaD, which forms the polymeric backbone of one of the three types of pilus expressed by C. diphtheriae, is reported. Mass-spectral and crystallographic analysis shows that SpaD contains three internal Lys–Asn isopeptide bonds. One of these, shown by mass spectrometry to be located in the N-terminal D1 domain of the protein, only forms slowly, implying an energy barrier to bond formation. Two crystal structures, of the full-length three-domain protein at 2.5 Å resolution and of a two-domain (D2-D3) construct at 1.87 Å resolution, show that each of the three Ig-like domains contains a single Lys–Asn isopeptide-bond cross-link, assumed to give mechanical stability as in other such pili. Additional stabilizing features include a disulfide bond in the D3 domain and a calcium-binding loop in D2. The N-terminal D1 domain is more flexible than the others and, by analogy with other major pilins of this type, the slow formation of its isopeptide bond can be attributed to its location adjacent to the lysine used in sortase-mediated polymerization during pilus assembly.

  3. Steered molecular dynamics simulations of a type IV pilus probe initial stages of a force-induced conformational transition.

    Directory of Open Access Journals (Sweden)

    Joseph L Baker

    2013-04-01

    Full Text Available Type IV pili are long, protein filaments built from a repeating subunit that protrudes from the surface of a wide variety of infectious bacteria. They are implicated in a vast array of functions, ranging from bacterial motility to microcolony formation to infection. One of the most well-studied type IV filaments is the gonococcal type IV pilus (GC-T4P from Neisseria gonorrhoeae, the causative agent of gonorrhea. Cryo-electron microscopy has been used to construct a model of this filament, offering insights into the structure of type IV pili. In addition, experiments have demonstrated that GC-T4P can withstand very large tension forces, and transition to a force-induced conformation. However, the details of force-generation, and the atomic-level characteristics of the force-induced conformation, are unknown. Here, steered molecular dynamics (SMD simulation was used to exert a force in silico on an 18 subunit segment of GC-T4P to address questions regarding the nature of the interactions that lead to the extraordinary strength of bacterial pili. SMD simulations revealed that the buried pilin α1 domains maintain hydrophobic contacts with one another within the core of the filament, leading to GC-T4P's structural stability. At the filament surface, gaps between pilin globular head domains in both the native and pulled states provide water accessible routes between the external environment and the interior of the filament, allowing water to access the pilin α1 domains as reported for VC-T4P in deuterium exchange experiments. Results were also compared to the experimentally observed force-induced conformation. In particular, an exposed amino acid sequence in the experimentally stretched filament was also found to become exposed during the SMD simulations, suggesting that initial stages of the force induced transition are well captured. Furthermore, a second sequence was shown to be initially hidden in the native filament and became exposed upon

  4. Purification, crystallization and preliminary X-ray diffraction analysis of the Escherichia coli common pilus chaperone EcpB.

    Science.gov (United States)

    Garnett, James A; Diallo, Mamou; Matthews, Steve J

    2015-06-01

    Pili are key cell-surface components that allow the attachment of bacteria to both biological and abiotic solid surfaces, whilst also mediating interactions between themselves. In Escherichia coli, the common pilus (Ecp) belongs to an alternative chaperone-usher (CU) pathway that plays a major role in both early biofilm formation and host-cell adhesion. The chaperone EcpB is involved in the biogenesis of the filament, which is composed of EcpA and EcpD. Initial attempts at crystallizing EcpB using natively purified protein from the bacterial periplasm were not successful; however, after the isolation of EcpB under denaturing conditions and subsequent refolding, crystals were obtained at pH 8.0 using the sitting-drop method of vapour diffusion. Diffraction data have been processed to 2.4 Å resolution. These crystals belonged to the trigonal space group P3(1)21 or P3(2)21, with unit-cell parameters a = b = 62.65, c = 121.14 Å and one monomer in the asymmetric unit. Molecular replacement was unsuccessful, but selenomethionine-substituted protein and heavy-atom derivatives are being prepared for phasing. The three-dimensional structure of EcpB will provide invaluable information on the subtle mechanistic differences in biogenesis between the alternative and classical CU pathways. Furthermore, this is the first time that this refolding strategy has been used to purify CU chaperones, and it could be implemented in similar systems where it has not been possible to obtain highly ordered crystals.

  5. Longus, a Type IV Pilus of Enterotoxigenic Escherichia coli, Is Involved in Adherence to Intestinal Epithelial Cells▿

    Science.gov (United States)

    Mazariego-Espinosa, Karina; Cruz, Ariadnna; Ledesma, Maria A.; Ochoa, Sara A.; Xicohtencatl-Cortes, Juan

    2010-01-01

    Enterotoxigenic Escherichia coli (ETEC) is the leading bacterial cause of diarrhea in the developing world, as well as the most common cause of traveler's diarrhea. The main hallmarks of this type of bacteria are the expression of one or more enterotoxins and fimbriae used for attachment to host intestinal cells. Longus is a pilus produced by ETEC. These bacteria grown in pleuropneumonia-like organism (PPLO) broth at 37°C and in 5% CO2 produced longus, showing that the assembly and expression of the pili depend on growth conditions and composition of the medium. To explore the role of longus in the adherence to epithelial cells, quantitative and qualitative analyses were done, and similar levels of adherence were observed, with values of 111.44 × 104 CFU/ml in HT-29, 101.33 × 104 CFU/ml in Caco-2, and 107.11 × 104 CFU/ml in T84 cells. In addition, the E9034AΔlngA strain showed a significant reduction in longus adherence of 32% in HT-29, 22.28% in Caco-2, and 21.68% in T84 cells compared to the wild-type strain. In experiments performed with nonintestinal cells (HeLa and HEp-2 cells), significant differences were not observed in adherence between E9034A and derivative strains. Interestingly, the E9034A and E9034AΔlngA(pLngA) strains were 30 to 35% more adherent in intestinal cells than in nonintestinal cells. Twitching motility experiments were performed, showing that ETEC strains E9034A and E9034AΔlngA(pLngA) had the capacity to form spreading zones while ETEC E9034AΔlngA does not. In addition, our data suggest that longus from ETEC participates in the colonization of human colonic cells. PMID:20348256

  6. Escherichia coli common pilus (ECP) targets arabinosyl residues in plant cell walls to mediate adhesion to fresh produce plants.

    Science.gov (United States)

    Rossez, Yannick; Holmes, Ashleigh; Lodberg-Pedersen, Henriette; Birse, Louise; Marshall, Jacqueline; Willats, William G T; Toth, Ian K; Holden, Nicola J

    2014-12-05

    Outbreaks of verotoxigenic Escherichia coli are often associated with fresh produce. However, the molecular basis to adherence is unknown beyond ionic lipid-flagellum interactions in plant cell membranes. We demonstrate that arabinans present in different constituents of plant cell walls are targeted for adherence by E. coli common pilus (ECP; or meningitis-associated and temperature-regulated (Mat) fimbriae) for E. coli serotypes O157:H7 and O18:K1:H7. l-Arabinose is a common constituent of plant cell wall that is rarely found in other organisms, whereas ECP is widespread in E. coli and other environmental enteric species. ECP bound to oligosaccharides of at least arabinotriose or longer in a glycan array, plant cell wall pectic polysaccharides, and plant glycoproteins. Recognition overlapped with the antibody LM13, which binds arabinanase-sensitive pectic epitopes, and showed a preferential affinity for (1→5)-α-linked l-arabinosyl residues and longer chains of arabinan as demonstrated with the use of arabinan-degrading enzymes. Functional adherence in planta was mediated by the adhesin EcpD in combination with the structural subunit, EcpA, and expression was demonstrated with an ecpR-GFP fusion and ECP antibodies. Spinach was found to be enriched for ECP/LM13 targets compared with lettuce. Specific recognition of arabinosyl residues may help explain the persistence of E. coli in the wider environment and association of verotoxigenic E. coli with some fresh produce plants by exploitation of a glycan found only in plant, not animal, cells.

  7. Evidence for the Sialylation of PilA, the PI-2a Pilus-Associated Adhesin of Streptococcus agalactiae Strain NEM316.

    Science.gov (United States)

    Morello, Eric; Mallet, Adeline; Konto-Ghiorghi, Yoan; Chaze, Thibault; Mistou, Michel-Yves; Oliva, Giulia; Oliveira, Liliana; Di Guilmi, Anne-Marie; Trieu-Cuot, Patrick; Dramsi, Shaynoor

    2015-01-01

    Streptococcus agalactiae (or Group B Streptococcus, GBS) is a commensal bacterium present in the intestinal and urinary tracts of approximately 30% of humans. We and others previously showed that the PI-2a pilus polymers, made of the backbone pilin PilB, the tip adhesin PilA and the cell wall anchor protein PilC, promote adhesion to host epithelia and biofilm formation. Affinity-purified PI-2a pili from GBS strain NEM316 were recognized by N-acetylneuraminic acid (NeuNAc, also known as sialic acid) specific lectins such as Elderberry Bark Lectin (EBL) suggesting that pili are sialylated. Glycan profiling with twenty different lectins combined with monosaccharide composition by HPLC suggested that affinity-purified PI-2a pili are modified by N-glycosylation and decorated with sialic acid attached to terminal galactose. Analysis of various relevant mutants in the PI-2a pilus operon by flow-cytometry and electron microscopy analyses pointed to PilA as the pilus subunit modified by glycosylation. Double labeling using PilB antibody and EBL lectin, which specifically recognizes N-acetylneuraminic acid attached to galactose in α-2, 6, revealed a characteristic binding of EBL at the tip of the pilus structures, highly reminiscent of PilA localization. Expression of a secreted form of PilA using an inducible promoter showed that this recombinant PilA binds specifically to EBL lectin when produced in the native GBS context. In silico search for potentially glycosylated asparagine residues in PilA sequence pointed to N427 and N597, which appear conserved and exposed in the close homolog RrgA from S. pneumoniae, as likely candidates. Conversion of these two asparagyl residues to glutamyl resulted in a higher instability of PilA. Our results provide the first evidence that the tip PilA adhesin can be glycosylated, and suggest that this modification is critical for PilA stability and may potentially influence interactions with the host.

  8. Identification of a TcpC-TcpQ Outer Membrane Complex Involved in the Biogenesis of the Toxin-Coregulated Pilus of Vibrio cholerae

    OpenAIRE

    Bose, Niranjan; Taylor, Ronald K.

    2005-01-01

    The toxin-coregulated pilus (TCP) of Vibrio cholerae and the soluble TcpF protein that is secreted via the TCP biogenesis apparatus are essential for intestinal colonization. The TCP biogenesis apparatus is composed of at least nine proteins but is largely uncharacterized. TcpC is an outer membrane lipoprotein required for TCP biogenesis that is a member of the secretin protein superfamily. In the present study, analysis of TcpC in a series of strains deficient in each of the TCP biogenesis p...

  9. Application of MLST and pilus gene sequence comparisons to investigate the population structures of Actinomyces naeslundii and Actinomyces oris

    NARCIS (Netherlands)

    Henssge, U.; Do, T.; Gilbert, S.C.; Cox, S.; Clark, D.; Wickström, C.; Ligtenberg, A.J.M.; Radford, D.R.; Beighton, D.

    2011-01-01

    Actinomyces naeslundii and Actinomyces oris are members of the oral biofilm. Their identification using 16S rRNA sequencing is problematic and better achieved by comparison of metG partial sequences. A. oris is more abundant and more frequently isolated than A. naeslundii. We used a multi-locus

  10. Role of the Emp Pilus Subunits of Enterococcus faecium in Biofilm Formation, Adherence to Host Extracellular Matrix Components, and Experimental Infection.

    Science.gov (United States)

    Montealegre, Maria Camila; Singh, Kavindra V; Somarajan, Sudha R; Yadav, Puja; Chang, Chungyu; Spencer, Robert; Sillanpää, Jouko; Ton-That, Hung; Murray, Barbara E

    2016-05-01

    Enterococcus faecium is an important cause of hospital-associated infections, including urinary tract infections (UTIs), bacteremia, and infective endocarditis. Pili have been shown to play a role in the pathogenesis of Gram-positive bacteria, including E. faecium We previously demonstrated that a nonpiliated ΔempABC::cat derivative of E. faecium TX82 was attenuated in biofilm formation and in a UTI model. Here, we studied the contributions of the individual pilus subunits EmpA, EmpB, and EmpC to pilus architecture, biofilm formation, adherence to extracellular matrix (ECM) proteins, and infection. We identified EmpA as the tip of the pili and found that deletion of empA reduced biofilm formation to the same level as deletion of the empABC operon, a phenotype that was restored by reconstituting in situ the empA gene. Deletion of empB also caused a reduction in biofilm, while EmpC was found to be dispensable. Significant reductions in adherence to fibrinogen and collagen type I were observed with deletion of empA and empB, while deletion of empC had no adherence defect. Furthermore, we showed that each deletion mutant was significantly attenuated in comparison to the isogenic parental strain, TX82, in a mixed-inoculum UTI model (P Emp pilins are important for E. faecium to cause infection in the urinary tract.

  11. A thiol-disulfide oxidoreductase of the Gram-positive pathogen Corynebacterium diphtheriae is essential for viability, pilus assembly, toxin production and virulence.

    Science.gov (United States)

    Reardon-Robinson, Melissa E; Osipiuk, Jerzy; Jooya, Neda; Chang, Chungyu; Joachimiak, Andrzej; Das, Asis; Ton-That, Hung

    2015-12-01

    The Gram-positive pathogen Corynebacterium diphtheriae exports through the Sec apparatus many extracellular proteins that include the key virulence factors diphtheria toxin and the adhesive pili. How these proteins attain their native conformations after translocation as unfolded precursors remains elusive. The fact that the majority of these exported proteins contain multiple cysteine residues and that several membrane-bound oxidoreductases are encoded in the corynebacterial genome suggests the existence of an oxidative protein-folding pathway in this organism. Here we show that the shaft pilin SpaA harbors a disulfide bond in vivo and alanine substitution of these cysteines abrogates SpaA polymerization and leads to the secretion of degraded SpaA peptides. We then identified a thiol-disulfide oxidoreductase (MdbA), whose structure exhibits a conserved thioredoxin-like domain with a CPHC active site. Remarkably, deletion of mdbA results in a severe temperature-sensitive cell division phenotype. This mutant also fails to assemble pilus structures and is greatly defective in toxin production. Consistent with these defects, the ΔmdbA mutant is attenuated in a guinea pig model of diphtheritic toxemia. Given its diverse cellular functions in cell division, pilus assembly and toxin production, we propose that MdbA is a component of the general oxidative folding machine in C. diphtheriae.

  12. Identification of Haloferax volcanii Pilin N-Glycans with Diverse Roles in Pilus Biosynthesis, Adhesion, and Microcolony Formation.

    Science.gov (United States)

    Esquivel, Rianne N; Schulze, Stefan; Xu, Rachel; Hippler, Michael; Pohlschroder, Mechthild

    2016-05-13

    N-Glycosylation is a post-translational modification common to all three domains of life. In many archaea, the oligosacharyltransferase (AglB)-dependent N-glycosylation of flagellins is required for flagella assembly. However, whether N-glycosylation is required for the assembly and/or function of the structurally related archaeal type IV pili is unknown. Here, we show that of six Haloferax volcanii adhesion pilins, PilA1 and PilA2, the most abundant pilins in pili of wild-type and ΔaglB strains, are modified under planktonic conditions in an AglB-dependent manner by the same pentasaccharide detected on H. volcanii flagellins. However, unlike wild-type cells, which have surfaces decorated with discrete pili and form a dispersed layer of cells on a plastic surface, ΔaglB cells have thick pili bundles and form microcolonies. Moreover, expressing PilA1, PilA2, or PilA6 in ΔpilA[1-6]ΔaglB stimulates microcolony formation compared with their expression in ΔpilA[1-6]. Conversely, expressing PilA3 or PilA4 in ΔpilA[1-6] cells results in strong surface adhesion, but not microcolony formation, and neither pilin stimulates surface adhesion in ΔpilA[1-6]ΔaglB cells. Although PilA4 assembles into pili in the ΔpilA[1-6]ΔaglB cells, these pili are, unlike wild-type pili, curled, perhaps rendering them non-functional. To our knowledge, this is the first demonstration of a differential effect of glycosylation on pilus assembly and function of paralogous pilins. The growth of wild-type cells in low salt media, a condition that decreases AglB glycosylation, also stimulates microcolony formation and inhibits motility, supporting our hypothesis that N-glycosylation plays an important role in regulating the transition between planktonic to sessile cell states as a response to stress.

  13. EL LOCUS DE DISTRIBUCION COMO COROLARIO DEL LOCUS DE CONTROL

    Directory of Open Access Journals (Sweden)

    Luisa Mayoral

    2009-01-01

    Full Text Available Este es un artículo científico acerca del Locus de Distribución, surgido de un estudio realizado con una población de docentes y alumnos universitarios. Respecto de los primeros, se ha indagado acerca de las atribuciones que se realizaban en torno a las recompensas y sanciones, que ellos distribuían a sus alumnos. Respecto de los segundos, se ha buscado determinar la valoración que estos realizaban de sus profesores, en términos de aquellas atribuciones. Para ello, se utilizaron dos paradigmas clásicamente empleados para verificar la existencia de una norma: el paradigma de la autopresentación (docentes, y el paradigma de los juicios (alumnos. La cuestión planteada fue determinar si en el caso de los comportamientos distributivos de refuerzos, las causas se atribuían a variables externas -en particular a los receptores de esos refuerzos- y si esas formas de atribución eran conocidas y valoradas o no, por los alumnos. De los resultados, surgió la confirmación de nuestra hipótesis de explicaciones externas en materia de comportamientos distributivos de sanciones en el ámbito de la docencia y la valoración positiva de estas atribuciones por los alumnos.

  14. Translocations affecting human immunoglobulin heavy chain locus

    Directory of Open Access Journals (Sweden)

    Sklyar I. V.

    2014-03-01

    Full Text Available Translocations involving human immunoglobulin heavy chain (IGH locus are implicated in different leukaemias and lymphomas, including multiple myeloma, mantle cell lymphoma, Burkitt’s lymphoma and diffuse large B cell lymphoma. We have analysed published data and identified eleven breakpoint cluster regions (bcr related to these cancers within the IgH locus. These ~1 kbp bcrs are specific for one or several types of blood cancer. Our findings could help devise PCR-based assays to detect cancer-related translocations, to identify the mechanisms of translocations and to help in the research of potential translocation partners of the immunoglobulin locus at different stages of B-cell differentiation.

  15. Locus of control and decision to abort.

    Science.gov (United States)

    Dixon, P N; Strano, D A; Willingham, W

    1984-04-01

    The relationship of locus of control to deciding on an abortion was investigated by administering Rotter's Locus of Control Scale to 118 women immediately prior to abortion and 2 weeks and 3 months following abortion. Subjects' scores were compared across the 3 time periods, and the abortion group's pretest scores were compared with those of a nonpregnant control, group. As hypothesized, the aborting group scored significantly more internal than the general population but no differences in locus of control were found across the 3 time period. The length of delay in deciding to abort an unwanted pregnancy following confirmation was also assessed. Women seeking 1st trimester abortions were divided into internal and external groups on the Rotter Scale and the lengths of delay were compared. The hypothesis that external scores would delay the decision longer than internal ones was confirmed. The results confirm characteristics of the locus of control construct and add information about personality characteristics of women undergoing abortion.

  16. Oral Immunization with a Recombinant Lactococcus lactis-Expressing HIV-1 Antigen on Group A Streptococcus Pilus Induces Strong Mucosal Immunity in the Gut.

    Science.gov (United States)

    Chamcha, Venkateswarlu; Jones, Andrew; Quigley, Bernard R; Scott, June R; Amara, Rama Rao

    2015-11-15

    The induction of a potent humoral and cellular immune response in mucosal tissue is important for the development of an effective HIV vaccine. Most of the current HIV vaccines under development use the i.m. route for immunization, which is relatively poor in generating potent and long-lived mucosal immune responses. In this article, we explore the ability of an oral vaccination with a probiotic organism, Lactococcus lactis, to elicit HIV-specific immune responses in the mucosal and systemic compartments of BALB/c mice. We expressed the HIV-1 Gag-p24 on the tip of the T3 pilus of Streptococcus pyogenes as a fusion to the Cpa protein (LL-Gag). After four monthly LL-Gag oral immunizations, we observed strong Gag-specific IgG and IgA responses in serum, feces, and vaginal secretions. However, the Gag-specific CD8 T cell responses in the blood were at or below our detection limit. After an i.m. modified vaccinia Ankara/Gag boost, we observed robust Gag-specific CD8 T cell responses both in systemic and in mucosal tissues, including intraepithelial and lamina propria lymphocytes of the small intestine, Peyer's patches, and mesenteric lymph nodes. Consistent with strong immunogenicity, the LL-Gag induced activation of CD11c(+) CD11b(+) dendritic cells in the Peyer's patches after oral immunization. Our results demonstrate that oral immunization with L. lactis expressing an Ag on the tip of the group A Streptococcus pilus serves as an excellent vaccine platform to induce strong mucosal humoral and cellular immunity against HIV.

  17. PilN Binding Modulates the Structure and Binding Partners of the Pseudomonas aeruginosa Type IVa Pilus Protein PilM.

    Science.gov (United States)

    McCallum, Matthew; Tammam, Stephanie; Little, Dustin J; Robinson, Howard; Koo, Jason; Shah, Megha; Calmettes, Charles; Moraes, Trevor F; Burrows, Lori L; Howell, P Lynne

    2016-05-20

    Pseudomonas aeruginosa is an opportunistic bacterial pathogen that expresses type IVa pili. The pilus assembly system, which promotes surface-associated twitching motility and virulence, is composed of inner and outer membrane subcomplexes, connected by an alignment subcomplex composed of PilMNOP. PilM binds to the N terminus of PilN, and we hypothesize that this interaction causes functionally significant structural changes in PilM. To characterize this interaction, we determined the crystal structures of PilM and a PilM chimera where PilM was fused to the first 12 residues of PilN (PilM·PilN(1-12)). Structural analysis, multiangle light scattering coupled with size exclusion chromatography, and bacterial two-hybrid data revealed that PilM forms dimers mediated by the binding of a novel conserved motif in the N terminus of PilM, and binding PilN abrogates this binding interface, resulting in PilM monomerization. Structural comparison of PilM with PilM·PilN(1-12) revealed that upon PilN binding, there is a large domain closure in PilM that alters its ATP binding site. Using biolayer interferometry, we found that the association rate of PilN with PilM is higher in the presence of ATP compared with ADP. Bacterial two-hybrid data suggested the connectivity of the cytoplasmic and inner membrane components of the type IVa pilus machinery in P. aeruginosa, with PilM binding to PilB, PilT, and PilC in addition to PilN. Pull-down experiments demonstrated direct interactions of PilM with PilB and PilT. We propose a working model in which dynamic binding of PilN facilitates functionally relevant structural changes in PilM.

  18. Homo-trimeric Structure of the Type IVb Minor Pilin CofB Suggests Mechanism of CFA/III Pilus Assembly in Human Enterotoxigenic Escherichia coli.

    Science.gov (United States)

    Kawahara, Kazuki; Oki, Hiroya; Fukakusa, Shunsuke; Yoshida, Takuya; Imai, Tomoya; Maruno, Takahiro; Kobayashi, Yuji; Motooka, Daisuke; Iida, Tetsuya; Ohkubo, Tadayasu; Nakamura, Shota

    2016-03-27

    In gram-negative bacteria, the assembly of type IV pilus (T4P) and the evolutionally related pseudopilus of type II secretion system involves specialized structural proteins called pilins and pseudopilins, respectively, and is dynamically regulated to promote bacterial pathogenesis. Previous studies have suggested that a structural "tip"-like hetero-complex formed through the interaction of at least three minor (pseudo) pilins plays an important role in this process, while some members of the pathogenic type IVb subfamily are known to have only one such minor pilin subunit whose function is still unknown. Here, we determined the crystal structure of the type IVb minor pilin CofB of colonization factor antigen/III from human enterotoxigenic Escherichia coli at 1.88-Å resolution. The crystal structure, in conjunction with physicochemical analysis in solution, reveals a symmetrical homo-trimeric arrangement distinct from the hetero-complexes of minor (pseudo) pilins observed in other T4P and type II secretion systems. Each CofB monomer adopts a unique three-domain architecture, in which the C-terminal β-sheet-rich lectin domain can effectively initiate trimer association of its pilin-like N-terminal domain through extensive hydrophobic interactions followed by domain swapping at the central hinge-like domain. Deletion of cofB produces a phenotype with no detectable pili formation on the cell surface, while molecular modeling indicates that the characteristic homo-trimeric structure of CofB is well situated at the pilus tip of colonization factor antigen/III formed by the major pilin CofA, suggesting a role for the minor pilin in the efficient initiation of T4P assembly. Copyright © 2016 Elsevier Ltd. All rights reserved.

  19. A slow-forming isopeptide bond in the structure of the major pilin SpaD from Corynebacterium diphtheriae has implications for pilus assembly.

    Science.gov (United States)

    Kang, Hae Joo; Paterson, Neil G; Kim, Chae Un; Middleditch, Martin; Chang, Chungyu; Ton-That, Hung; Baker, Edward N

    2014-05-01

    The Gram-positive organism Corynebacterium diphtheriae, the cause of diphtheria in humans, expresses pili on its surface which it uses for adhesion and colonization of its host. These pili are covalent protein polymers composed of three types of pilin subunit that are assembled by specific sortase enzymes. A structural analysis of the major pilin SpaD, which forms the polymeric backbone of one of the three types of pilus expressed by C. diphtheriae, is reported. Mass-spectral and crystallographic analysis shows that SpaD contains three internal Lys-Asn isopeptide bonds. One of these, shown by mass spectrometry to be located in the N-terminal D1 domain of the protein, only forms slowly, implying an energy barrier to bond formation. Two crystal structures, of the full-length three-domain protein at 2.5 Å resolution and of a two-domain (D2-D3) construct at 1.87 Å resolution, show that each of the three Ig-like domains contains a single Lys-Asn isopeptide-bond cross-link, assumed to give mechanical stability as in other such pili. Additional stabilizing features include a disulfide bond in the D3 domain and a calcium-binding loop in D2. The N-terminal D1 domain is more flexible than the others and, by analogy with other major pilins of this type, the slow formation of its isopeptide bond can be attributed to its location adjacent to the lysine used in sortase-mediated polymerization during pilus assembly.

  20. The Enterococcus faecalis EbpA Pilus Protein: Attenuation of Expression, Biofilm Formation, and Adherence to Fibrinogen Start with the Rare Initiation Codon ATT

    Science.gov (United States)

    Montealegre, Maria Camila; La Rosa, Sabina Leanti; Roh, Jung Hyeob; Harvey, Barrett R.

    2015-01-01

    ABSTRACT The endocarditis and biofilm-associated pili (Ebp) are important in Enterococcus faecalis pathogenesis, and the pilus tip, EbpA, has been shown to play a major role in pilus biogenesis, biofilm formation, and experimental infections. Based on in silico analyses, we previously predicted that ATT is the EbpA translational start codon, not the ATG codon, 120 bp downstream of ATT, which is annotated as the translational start. ATT is rarely used to initiate protein synthesis, leading to our hypothesis that this codon participates in translational regulation of Ebp production. To investigate this possibility, site-directed mutagenesis was used to introduce consecutive stop codons in place of two lysines at positions 5 and 6 from the ATT, to replace the ATT codon in situ with ATG, and then to revert this ATG to ATT; translational fusions of ebpA to lacZ were also constructed to investigate the effect of these start codons on translation. Our results showed that the annotated ATG does not start translation of EbpA, implicating ATT as the start codon; moreover, the presence of ATT, compared to the engineered ATG, resulted in significantly decreased EbpA surface display, attenuated biofilm, and reduced adherence to fibrinogen. Corroborating these findings, the translational fusion with the native ATT as the initiation codon showed significantly decreased expression of β-galactosidase compared to the construct with ATG in place of ATT. Thus, these results demonstrate that the rare initiation codon of EbpA negatively regulates EbpA surface display and negatively affects Ebp-associated functions, including biofilm and adherence to fibrinogen. PMID:26015496

  1. Search, Effort, and Locus of Control

    OpenAIRE

    McGee, Andrew; McGee, Peter

    2011-01-01

    We test the hypothesis that locus of control – one's perception of control over events in life – influences search by affecting beliefs about the efficacy of search effort in a laboratory experiment. We find that reservation offers and effort are increasing in the belief that one's efforts influence outcomes when subjects exert effort without knowing how effort influences the generation of offers but are unrelated to locus of control beliefs when subjects are informed about the relationship b...

  2. Culture, gender and locus of control

    DEFF Research Database (Denmark)

    Ottsen, Christina Lundsgaard; Johannessen, Kim Berg; Berntsen, Dorthe

    The current study is a cross-cultural comparison between the Middle East and Scandinavia. Two societies that offer a unique opportunity to examine gender differences in personal goals and how goals are affected by locus of control.......The current study is a cross-cultural comparison between the Middle East and Scandinavia. Two societies that offer a unique opportunity to examine gender differences in personal goals and how goals are affected by locus of control....

  3. Identification and phenotypic characterization of a second collagen adhesin, Scm, and genome-based identification and analysis of 13 other predicted MSCRAMMs, including four distinct pilus loci, in Enterococcus faecium.

    Science.gov (United States)

    Sillanpää, Jouko; Nallapareddy, Sreedhar R; Prakash, Vittal P; Qin, Xiang; Höök, Magnus; Weinstock, George M; Murray, Barbara E

    2008-10-01

    Attention has recently been drawn to Enterococcus faecium because of an increasing number of nosocomial infections caused by this species and its resistance to multiple antibacterial agents. However, relatively little is known about the pathogenic determinants of this organism. We have previously identified a cell-wall-anchored collagen adhesin, Acm, produced by some isolates of E. faecium, and a secreted antigen, SagA, exhibiting broad-spectrum binding to extracellular matrix proteins. Here, we analysed the draft genome of strain TX0016 for potential microbial surface components recognizing adhesive matrix molecules (MSCRAMMs). Genome-based bioinformatics identified 22 predicted cell-wall-anchored E. faecium surface proteins (Fms), of which 15 (including Acm) had characteristics typical of MSCRAMMs, including predicted folding into a modular architecture with multiple immunoglobulin-like domains. Functional characterization of one [Fms10; redesignated second collagen adhesin of E. faecium (Scm)] revealed that recombinant Scm(65) (A- and B-domains) and Scm(36) (A-domain) bound to collagen type V efficiently in a concentration-dependent manner, bound considerably less to collagen type I and fibrinogen, and differed from Acm in their binding specificities to collagen types IV and V. Results from far-UV circular dichroism measurements of recombinant Scm(36) and of Acm(37) indicated that these proteins were rich in beta-sheets, supporting our folding predictions. Whole-cell ELISA and FACS analyses unambiguously demonstrated surface expression of Scm in most E. faecium isolates. Strikingly, 11 of the 15 predicted MSCRAMMs clustered in four loci, each with a class C sortase gene; nine of these showed similarity to Enterococcus faecalis Ebp pilus subunits and also contained motifs essential for pilus assembly. Antibodies against one of the predicted major pilus proteins, Fms9 (redesignated EbpC(fm)), detected a 'ladder' pattern of high-molecular-mass protein bands in a

  4. Locus heterogeneity in autosomal dominant spinocerebellar ataxia: Evidence for the existence of a fifth locus

    Energy Technology Data Exchange (ETDEWEB)

    Sarrazin, J.; Rouleau, G.A. [Montreal General Hospital, Quebec (Canada); Andermann, E. [Montreal Neurological Institute and Hospital, Quebec (Canada)] [and others

    1994-09-01

    The autosomal dominantly inherited spinocerebellar ataxias (SCAs) are a heterogeneous group of neurodegenerative disorders. To date, four loci have been identified: the SCA-1 locus (on chromosome (chr) 6p), the SCA-2 locus (on chr 12q), the SCA-3/MJD locus (on chr 14q), and more recently an SCA-4 locus was described (chr 16q) in a Utah kindred. We have studied one large French Canadian kindred with four generations of living affected individuals segregating an autosomal dominant form of SCA. Linkage analysis using anonymous DNA markers which flank the four previously described loci significantly excludes the French Canadian kindred from the SCA-1, SCA-2, SCA-3/MJD and SCA-4 loci. Therefore a fifth, still unmapped, SCA locus remains to be identified.

  5. Helicobacter pylori exploits a unique repertoire of type IV secretion system components for pilus assembly at the bacteria-host cell interface.

    Directory of Open Access Journals (Sweden)

    Carrie L Shaffer

    2011-09-01

    Full Text Available Colonization of the human stomach by Helicobacter pylori is an important risk factor for development of gastric cancer. The H. pylori cag pathogenicity island (cag PAI encodes components of a type IV secretion system (T4SS that translocates the bacterial oncoprotein CagA into gastric epithelial cells, and CagL is a specialized component of the cag T4SS that binds the host receptor α5β1 integrin. Here, we utilized a mass spectrometry-based approach to reveal co-purification of CagL, CagI (another integrin-binding protein, and CagH (a protein with weak sequence similarity to CagL. These three proteins are encoded by contiguous genes in the cag PAI, and are detectable on the bacterial surface. All three proteins are required for CagA translocation into host cells and H. pylori-induced IL-8 secretion by gastric epithelial cells; however, these proteins are not homologous to components of T4SSs in other bacterial species. Scanning electron microscopy analysis reveals that these proteins are involved in the formation of pili at the interface between H. pylori and gastric epithelial cells. ΔcagI and ΔcagL mutant strains fail to form pili, whereas a ΔcagH mutant strain exhibits a hyperpiliated phenotype and produces pili that are elongated and thickened compared to those of the wild-type strain. This suggests that pilus dimensions are regulated by CagH. A conserved C-terminal hexapeptide motif is present in CagH, CagI, and CagL. Deletion of these motifs results in abrogation of CagA translocation and IL-8 induction, and the C-terminal motifs of CagI and CagL are required for formation of pili. In summary, these results indicate that CagH, CagI, and CagL are components of a T4SS subassembly involved in pilus biogenesis, and highlight the important role played by unique constituents of the H. pylori cag T4SS.

  6. A suppressor locus for MODY3-diabetes

    Science.gov (United States)

    Garcia-Gonzalez, Miguel A.; Carette, Claire; Bagattin, Alessia; Chiral, Magali; Makinistoglu, Munevver Parla; Garbay, Serge; Prévost, Géraldine; Madaras, Cécile; Hérault, Yann; Leibovici, Michel; Pontoglio, Marco

    2016-01-01

    Maturity Onset Diabetes of the Young type 3 (MODY3), linked to mutations in the transcription factor HNF1A, is the most prevalent form of monogenic diabetes mellitus. HNF1alpha-deficiency leads to defective insulin secretion via a molecular mechanism that is still not completely understood. Moreover, in MODY3 patients the severity of insulin secretion can be extremely variable even in the same kindred, indicating that modifier genes may control the onset of the disease. With the use of a mouse model for HNF1alpha-deficiency, we show here that specific genetic backgrounds (C3H and CBA) carry a powerful genetic suppressor of diabetes. A genome scan analysis led to the identification of a major suppressor locus on chromosome 3 (Moda1). Moda1 locus contains 11 genes with non-synonymous SNPs that significantly interacts with other loci on chromosomes 4, 11 and 18. Mechanistically, the absence of HNF1alpha in diabetic-prone (sensitive) strains leads to postnatal defective islets growth that is remarkably restored in resistant strains. Our findings are relevant to human genetics since Moda1 is syntenic with a human locus identified by genome wide association studies of fasting glycemia in patients. Most importantly, our results show that a single genetic locus can completely suppress diabetes in Hnf1a-deficiency. PMID:27667715

  7. Locus of Equity and Brand Extension

    NARCIS (Netherlands)

    S.M.J. van Osselaer (Stijn); J.W. Alba (Joseph)

    2003-01-01

    textabstractPrevailing wisdom assumes that brand equity increases when a brand touts its desirable attributes. We report conditions under which the use of attribute information to promote a product can shift the locus of equity from brand to attribute, thereby reducing the attractiveness of extensio

  8. Locus of Equity and Brand Extension

    NARCIS (Netherlands)

    S.M.J. van Osselaer (Stijn); J.W. Alba (Joseph)

    2003-01-01

    textabstractPrevailing wisdom assumes that brand equity increases when a brand touts its desirable attributes. We report conditions under which the use of attribute information to promote a product can shift the locus of equity from brand to attribute, thereby reducing the attractiveness of extensio

  9. Intranasal immunization with recombinant toxin-coregulated pilus and cholera toxin B subunit protects rabbits against Vibrio cholerae O1 challenge.

    Science.gov (United States)

    Kundu, Juthika; Mazumder, Rupa; Srivastava, Ranjana; Srivastava, Brahm S

    2009-07-01

    Intranasal immunization, a noninvasive method of vaccination, has been found to be effective in inducing systemic and mucosal immune responses. The present study was aimed at investigating the efficacy of intranasal immunization in inducing mucosal immunity in experimental cholera by subunit recombinant protein vaccines from Vibrio cholerae O1. The structural genes encoding toxin-coregulated pilus A (TcpA) and B subunit of cholera toxin (CtxB) from V. cholerae O1 were cloned and expressed in Escherichia coli. Rabbits were immunized intranasally with purified TcpA and CtxB alone or a mixture of TcpA and CtxB. Immunization with TcpA and CtxB alone conferred, respectively, 41.1% and 70.5% protection against V. cholerae challenge, whereas immunization with a mixture of both antigens conferred complete (100%) protection, as assayed in the rabbit ileal loop model. Serum titers of immunoglobulin G (IgG) antibodies to TcpA and CtxB, and anti-TcpA- and anti-CtxB-specific sIgA in intestinal lavage of vaccinated animals were found to be significantly elevated compared with unimmunized controls. Vibriocidal antibodies were detected at remarkable levels in rabbits receiving TcpA antigen and their titers correlated with protection. Thus, mucosal codelivery of pertinent cholera toxoids provides enhanced protection against experimental cholera.

  10. Self-Esteem, Locus of Control, and Student Achievement.

    Science.gov (United States)

    Sterbin, Allan; Rakow, Ernest

    The direct effects of locus of control and self-esteem on standardized test scores were studied. The relationships among the standardized test scores and measures of locus of control and self-esteem for 12,260 students from the National Education Longitudinal Study 1994 database were examined, using the same definition of locus of control and…

  11. Animal Protection and Structural Studies of a Consensus Sequence Vaccine Targeting the Receptor Binding Domain of the Type IV Pilus of Pseudomonas aeruginosa

    Energy Technology Data Exchange (ETDEWEB)

    Kao, Daniel J.; Churchill, Mair E.A.; Irvin, Randall T.; Hodges, Robert S. (Alberta); (Colorado)

    2008-09-23

    One of the main obstacles in the development of a vaccine against Pseudomonas aeruginosa is the requirement that it is protective against a wide range of virulent strains. We have developed a synthetic-peptide consensus-sequence vaccine (Cs1) that targets the host receptor-binding domain (RBD) of the type IV pilus of P. aeruginosa. Here, we show that this vaccine provides increased protection against challenge by the four piliated strains that we have examined (PAK, PAO, KB7 and P1) in the A.BY/SnJ mouse model of acute P. aeruginosa infection. To further characterize the consensus sequence, we engineered Cs1 into the PAK monomeric pilin protein and determined the crystal structure of the chimeric Cs1 pilin to 1.35 {angstrom} resolution. The substitutions (T130K and E135P) used to create Cs1 do not disrupt the conserved backbone conformation of the pilin RBD. In fact, based on the Cs1 pilin structure, we hypothesize that the E135P substitution bolsters the conserved backbone conformation and may partially explain the immunological activity of Cs1. Structural analysis of Cs1, PAK and K122-4 pilins reveal substitutions of non-conserved residues in the RBD are compensated for by complementary changes in the rest of the pilin monomer. Thus, the interactions between the RBD and the rest of the pilin can either be mediated by polar interactions of a hydrogen bond network in some strains or by hydrophobic interactions in others. Both configurations maintain a conserved backbone conformation of the RBD. Thus, the backbone conformation is critical in our consensus-sequence vaccine design and that cross-reactivity of the antibody response may be modulated by the composition of exposed side-chains on the surface of the RBD. This structure will guide our future vaccine design by focusing our investigation on the four variable residue positions that are exposed on the RBD surface.

  12. Expression of toxin co-regulated pilus subunit A (TCPA) of Vibrio cholerae and its immunogenic epitopes fused to cholera toxin B subunit in transgenic tomato (Solanum lycopersicum).

    Science.gov (United States)

    Sharma, Manoj Kumar; Singh, Nirmal Kumar; Jani, Dewal; Sisodia, Rama; Thungapathra, M; Gautam, J K; Meena, L S; Singh, Yogendra; Ghosh, Amit; Tyagi, Akhilesh Kumar; Sharma, Arun Kumar

    2008-02-01

    For protection against cholera, it is important to develop efficient vaccine capable of inducing anti-toxin as well as anti-colonizing immunity against Vibrio cholerae infections. Earlier, expression of cholera toxin B subunit (CTB) in tomato was reported by us. In the present investigation, toxin co-regulated pilus subunit A (TCPA), earlier reported to be an antigen capable of providing anti-colonization immunity, has been expressed in tomato. Further, to generate more potent combinatorial antigens, nucleotides encoding P4 or P6 epitope of TCPA were fused to cholera toxin B subunit gene (ctxB) and expressed in tomato. Presence of transgenes in the tomato genome was confirmed by PCR and expression of genes was confirmed at transcript and protein level. TCPA, chimeric CTB-P4 and CTB-P6 proteins were also expressed in E. coli. TCPA protein expressed in E. coli was purified to generate anti-TCPA antibodies in rabbit. Immunoblot and G(M1)-ELISA verified the synthesis and assembly of pentameric chimeric proteins in fruit tissue of transgenic tomato plants. The chimeric protein CTB-P4 and CTB-P6 accumulated up to 0.17 and 0.096% of total soluble protein (TSP), respectively, in tomato fruits. Whereas expression of TCPA, CTB-P4 and CTB-P6 in E. coli can be utilized for development of conventional vaccine, expression of these antigens which can provide both anti-toxin as well as anti-colonization immunity, has been demonstrated in plants, in a form which is potentially capable of inducing immune response against cholera infection.

  13. Typing of the pilus-protein-encoding FCT region and biofilm formation as novel parameters in epidemiological investigations of Streptococcus pyogenes isolates from various infection sites.

    Science.gov (United States)

    Köller, Thomas; Manetti, Andrea Guido Oreste; Kreikemeyer, Bernd; Lembke, Cordula; Margarit, Immaculada; Grandi, Guido; Podbielski, Andreas

    2010-04-01

    Streptococcus pyogenes is an important human pathogen for which an association between infection site and selected epidemiological or functional markers has previously been suggested. However, the studies involved often used strains with an insufficiently defined clinical background and laboratory history. Thus, the major goal of the present study was to investigate these relationships in 183 prospectively collected, well-defined, low-passage isolates from a North-East German centre for tertiary care. For each isolate the clinical background (91 respiratory, 71 skin and 21 invasive isolates) and antibiotic-resistance pattern was recorded. All isolates were classified according to their emm type, antibiotic-resistance and PFGE pattern ( SmaI restriction analysis of genomic DNA). As novel discriminatory methods we performed a PCR-based typing of the pilus-protein-encoding FCT region (FCT) and biofilm-formation phenotyping in various culture media. Forty-one isolates were found to be resistant to at least one of the tested antibiotics. emm typing revealed emm28, emm12 , emm1, emm4, emm89 and emm2 as the most frequent types in our collection. The novel FCT typing showed isolates encoding FCT types 4 and 2 to be the most common. Overall 113 strains with unique combinations of emm and FCT types, antibiotic-resistance and PFGE patterns were identified. The majority of all isolates revealed an association of biofilm-formation capacity with growth media. Comparing all results for potential associations, no correlation could be established between the anatomical site of isolation and the emm or the FCT type. There was no relationship between biofilm formation and emm type, antibiotic-resistance or PFGE patterns. However, a novel association between biofilm formation and FCT type became obvious among strains from our collection.

  14. Regulatory organization of the staphylococcal sae locus.

    Science.gov (United States)

    Adhikari, Rajan P; Novick, Richard P

    2008-03-01

    This paper describes an investigation of the complex internal regulatory circuitry of the staphylococcal sae locus and the impact of modifying this circuitry on the expression of external genes in the sae regulon. The sae locus contains four genes, the saeR and S two-component signalling module (TCS), and saeP and Q, two upstream genes of hitherto unknown function. It is expressed from two promoters, P(A)sae, which transcribes only the TCS, and P(C)sae, which transcribes the entire locus. A bursa aurealis (bursa) transposon insertion in saeP in a derivative of Staphylococcus aureus NCTC 8325 has a profound effect on sae function. It modifies the activity of the TCS, changing the expression of many genes in the sae regulon, even though transcription of the TCS (from P(A)sae) is not interrupted. Moreover, these effects are not due to disruption of saeP since an in-frame deletion in saeP has essentially no phenotype. The phenotype of S. aureus strain Newman is remarkably similar to that of the saeP : : bursa and this similarity is explained by an amino acid substitution in the Newman saeS gene that is predicted to modify profoundly the signalling function of the protein. This concurrence suggests that the saeP : : bursa insertion affects the signalling function of saeS, a suggestion that is supported by the ability of an saeQR clone, but not an saeR clone, to complement the effects of the saeP : : bursa insertion.

  15. Locus of control and online learning

    Directory of Open Access Journals (Sweden)

    Suretha Esterhuysen

    2004-10-01

    Full Text Available The integration of online learning in university courses is considered to be both inevitable and necessary. Thus there is an increasing need to raise awareness among educators and course designers about the critical issues impacting on online learning. The aim of this study, therefore, was to assess the differences between two groups of first-year Business Sciences learners (online and conventional learners in terms of biographic and demographic characteristics and locus of control. The study population consisted of 586 first-year learners of whom 185 completed the Locus of Control Inventory (LCI. The results show that the two groups of learners do not differ statistically significantly from each other with respect to locus of control. The findings and their implications are also discussed. Opsomming Die integrasie van aanlyn-leer in universiteitskursusse word beskou as sowel onafwendbaar as noodsaaklik. Daar is dus ’n toenemende behoefte om bewustheid onder opvoedkundiges en kursusontwerpers te kweek oor die kritiese aspekte wat ’n impak op aanlyn-leer het (Morgan, 1996. Daarom was die doel van hierdie ondersoek om die verskille tussen twee groepe eerstejaarleerders in Bestuurs- en Ekonomiese Wetenskap (aanlyn en konvensionele leerders te bepaal ten opsigte van biografiese en demografiese eienskappe en lokus van beheer. Die populasie het bestaan uit 586 eerstejaarleerders waarvan 185 die Lokus van Beheer Vraelys voltooi het. Die resultate toon dat die twee groepe leerders nie statisties beduidend van mekaar verskil het met betrekking tot lokus van beheer nie. Die bevindinge en implikasies word ook bespreek.

  16. Cut Locus Construction using Deformable Simplicial Complexes

    DEFF Research Database (Denmark)

    Misztal, Marek Krzysztof; Bærentzen, Jakob Andreas; Anton, François

    2011-01-01

    In this paper we present a method for appproximating cut loci for a given point p on Riemannian 2D manifolds, closely related to the notion of Voronoi diagrams. Our method finds the cut locus by advecting a front of points equally distant from p along the geodesics originating at p and finding...... the lines of self-intersections of the front in the parametric space. This becomes possible by using the deformable simplicial complexes (DSC, [1]) method for deformable interface tracking. DSC provide a simple collision detection mechanism, allows for interface topology control, and does not require...

  17. Impact of locus of control on health message effectiveness.

    Science.gov (United States)

    Kong, Ying; Shen, Fuyuan

    2011-10-01

    This article examined how individuals' locus of control might moderate the effect of health message frames. An experiment was conducted whereby participants read either individual- or social-responsibility message frames after their locus of control was primed. Results indicated that messages presented in individual-responsibility frames were more persuasive when people were primed with internal locus of control, whereas social-responsibility framed appeals were more persuasive when people were primed with external locus of control. These results were found for individuals in both high and low cognitive load conditions. Theoretical and practical implications of the findings are discussed.

  18. Relationships between locus of control and paranormal beliefs.

    Science.gov (United States)

    Newby, Robert W; Davis, Jessica Boyette

    2004-06-01

    The present study investigated the associations between scores on paranormal beliefs, locus of control, and certain psychological processes such as affect and cognitions as measured by the Linguistic Inquiry and Word Count. Analysis yielded significant correlations between scores on Locus of Control and two subscales of Tobacyk's (1988) Revised Paranormal Beliefs Scale, New Age Philosophy and Traditional Paranormal Beliefs. A step-wise multiple regression analysis indicated that Locus of Control was significantly related to New Age Philosophy. Other correlations were found between Tobacyk's subscales, Locus of Control, and three processes measured by the Linguistic Inquiry and Word Count.

  19. Inside the CBF locus in Poaceae.

    Science.gov (United States)

    Tondelli, Alessandro; Francia, Enrico; Barabaschi, Delfina; Pasquariello, Marianna; Pecchioni, Nicola

    2011-01-01

    Several molecular evidences have been gathered in Poaceae that point out a central role of the CBF/DREB1 transcription factors in the signal transduction pathways leading to low-temperature tolerance, although to a quite different extent between crops originating from either temperate or tropical climates. A common feature of the CBF/DREB1 genes in Poaceae is their structural organization at the genome level in clusters of tandemly duplicated genes. In temperate cereals such as barley and wheat, expansion of specific multigene phylogenetic clades of CBFs that map at the Frost Resistance-2 locus has been exclusively observed. In addition, copy number variants of CBF genes between frost resistant and frost sensitive genotypes raise the question if multiple copies of the CBF/DREB1s are required to ensure freezing tolerance. On the other hand, in crops of tropical origin such as rice and maize, a smaller or less-responsive CBF regulon may have evolved, and different mechanisms might determine chilling tolerance. In this review, recent advances on the organization and diversity at the CBF cluster locus in the grasses are provided and discussed. Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.

  20. Research Advances on Type 1 Pilus of Uropathogenic Escherichia coli%尿道致病性大肠杆菌Ⅰ型菌毛的研究进展

    Institute of Scientific and Technical Information of China (English)

    杨东靖; 葛新; 李力

    2011-01-01

    Urinary tract infections are serious public health problem worldwide. Strains of uropathogenic Escherichia coli (UPEC)are the primary cause of urinary tract infections. Type 1 pilus of UPEC is a very important virulence factor,widely distributed in UPEC,and mediates its adhesion, invasion and colonization in the urinary tract. The structure, assembly and virulence mechanism of type 1 pilus were reviewed in this paper.%泌尿道感染(Urinary tract infections,UTIs)是世界范围内严重的公共卫生问题.尿道致病性大肠杆菌(Uropathogenic Escherichia coli,UPEC)是引发UTIs的首要致病菌.I型菌毛是UPEC重要的毒力因子,在UPEC中分布广泛,介导其住泌尿道的粘附、侵入和定植.该文对UPEC I型菌毛的结构、装配和毒力机制进行综述.

  1. Turkish population data on the short tandem repeat locus TPOX

    DEFF Research Database (Denmark)

    Vural, B; Poda, M; Atlioglu, E;

    1998-01-01

    Allele and genotype frequencies were determined for the STR (short tandem repeat) locus TPOX in a random Turkish population sample of 200 individuals.......Allele and genotype frequencies were determined for the STR (short tandem repeat) locus TPOX in a random Turkish population sample of 200 individuals....

  2. Metacognition: As a Predictor of One's Academic Locus of Control

    Science.gov (United States)

    Arslan, Serhat; Akin, Ahmet

    2014-01-01

    The purpose of this study is to examine the effect of metacognition on one's academic locus of control. The study's sample group consists of 451 university students enrolled in various programs at Sakarya University, Turkey. In this study, the Metacognitive Awareness Inventory and the Academic Locus of Control Scale were used. The correlations and…

  3. Locus of Control, Attitudes toward Education, and Teaching Behaviors.

    Science.gov (United States)

    Kremer, Lya

    1982-01-01

    Tests 191 elementary school teachers in northern Israel for the relationships among locus of control, traditional and progressive educational attitudes, and related teaching behaviors. Finds external and internal locus of control explain the variance in traditional and progressive attitudes, respectively, and teaching behaviors. (Author/LC)

  4. The Cut Locus of a Torus of Revolution

    DEFF Research Database (Denmark)

    Gravesen, Jens; Markvorsen, Steen; Sinclair, Robert

    2005-01-01

    We determine the structure of the cut locus of a class of tori of revolution, which includes the standard tori in 3-dimensional Euclidean space.......We determine the structure of the cut locus of a class of tori of revolution, which includes the standard tori in 3-dimensional Euclidean space....

  5. Locus of control and investment in risky assets

    NARCIS (Netherlands)

    Salamanca, N.; de Grip, A.; Fouarge, D.; Montizaan, R.M.

    2013-01-01

    Using representative household panel data, we show that the investment behavior of households is related to the economic locus of control of household heads. A household's internal locus of control in economic issues is positively related to its decision to hold risky assets as well as its share of

  6. Locus of Control and Protection of Consumer Rights

    Directory of Open Access Journals (Sweden)

    Ivan Krastev

    2012-10-01

    Full Text Available This paper examines the influence of locus of control on the consumer behavior. Theoretical supposition is proven by analyzing empirical data from a study of 287 students. The methods assessed the capacity for defending personal and consumer rights, as well as the type of locus of control.

  7. Locus of Control in Underachieving and Achieving Gifted Students.

    Science.gov (United States)

    McClelland, Robert; And Others

    1991-01-01

    This study, with 87 underachieving and 77 achieving gifted students in grades 6-9, found that general locus of control measures did not differentiate between the 2 groups, that both scored significantly higher on positive internal than on negative internal locus of control, and that there were no gender or grade effects. (Author/DB)

  8. Locus of Control and Marital Stability: A Longitudinal Study.

    Science.gov (United States)

    Constantine, John A.; Bahr, Stephen J.

    1980-01-01

    Investigated relationship between locus of control and marital stability of young men. Factors derived from locus of control measures included leadership, personal, and fate scales. Results indicated the only significant difference was on the leadership scale between men remaining married and those who did not. (RC)

  9. Personality and Locus of Control among School Children

    Science.gov (United States)

    Pandya, Archana A.; Jogsan, Yogesh A.

    2013-01-01

    The main purpose of this investigation is to find out the sex differences in personality traits and locus of control among school children. A total 60 children (30 boys and 30 girls) were taken as a sample. The research tool for personality, children personality questionnaire was used, which was made by Cattell and Porter. Locus of control was…

  10. Is this Red Spot the Blue Spot (locus ceruleum)?

    Energy Technology Data Exchange (ETDEWEB)

    Choe, Won Sick; Lee, Yu Kyung; Lee, Min Kyung; Hwang, Kyung Hoon [Gachon University Gil Hospital, Incheon (Korea, Republic of)

    2010-06-15

    The authors report brain images of 18F-FDG-PET in a case of schizophrenia. The images showed strikingly increased bilateral uptake in the locus ceruleum. The locus ceruleum is called the blue spot and known to be a center of the norepinephrinergic system.

  11. Locus of Control in Underachieving and Achieving Gifted Students.

    Science.gov (United States)

    McClelland, Robert; And Others

    1991-01-01

    This study, with 87 underachieving and 77 achieving gifted students in grades 6-9, found that general locus of control measures did not differentiate between the 2 groups, that both scored significantly higher on positive internal than on negative internal locus of control, and that there were no gender or grade effects. (Author/DB)

  12. Physical Attractiveness, Locus of Control, Sex Role, and Conversational Assertiveness.

    Science.gov (United States)

    Campbell, Keith F.; And Others

    1990-01-01

    Analyzes the relationship among physical attractiveness, locus of control, sex role orientation, and assertiveness in undergraduate students. Reviews videotapes of mixed-sex student groups engaged in discussion. Finds an internal locus of control positively correlated with assertiveness. Uses a behavioral measure of assertiveness rather than…

  13. Sign Stability via Root Locus Analysis

    CERN Document Server

    Gibson, Travis E

    2015-01-01

    With the rise of network science old topics in ecology and economics are resurfacing. One such topic is structural stability (often referred to as qualitative stability or sign stability). A system is deemed structurally stable if the system remains stable for all possible parameter variations so long as the parameters do not change sign. This type of stability analysis is appealing when studying real systems as the underlying stability result only requires the scientist or engineer to know the sign of the parameters in the model and not the specific values. The necessary and sufficient conditions for qualitative stability however are opaque. In order to shed light on those conditions root locus analysis is employed. This technique allows us to illustrate the necessary conditions for qualitative stability.

  14. Cut Locus Construction using Deformable Simplicial Complexes

    DEFF Research Database (Denmark)

    Misztal, Marek Krzysztof; Bærentzen, Jakob Andreas; Anton, François;

    2011-01-01

    In this paper we present a method for appproximating cut loci for a given point p on Riemannian 2D manifolds, closely related to the notion of Voronoi diagrams. Our method finds the cut locus by advecting a front of points equally distant from p along the geodesics originating at p and finding...... the domain to have disk topology. We test our method for tori of revolution and compare our results to the benchmark ones from [2]. The method, however, is generic and can be easily adapted to construct cut loci for other manifolds of genera other than 1....... the lines of self-intersections of the front in the parametric space. This becomes possible by using the deformable simplicial complexes (DSC, [1]) method for deformable interface tracking. DSC provide a simple collision detection mechanism, allows for interface topology control, and does not require...

  15. Effects of preferred retinal locus placement on text navigation and development of advantageous trained retinal locus.

    Science.gov (United States)

    Watson, Gale R; Schuchard, Ronald A; De l'Aune, William R; Watkins, Erica

    2006-01-01

    Sixty readers were evaluated for visual function and text-navigation ability. The visual field and preferred retinal locus (PRL) were measured with a scanning laser ophthalmoscope (SLO). We found significant differences in text-navigation ability based on scotoma and PRL placement. Readers with a PRL to the left of or above a scotoma had significantly less text-navigation abilities. Readers with a PRL to the left of a scotoma tended to misread words with similar beginnings and omit the last word on a line. Readers with a PRL above a scotoma tended to skip a line or reread the same line twice. In a follow-up study, seven subjects with a nonadvantageous PRL quickly developed a trained retinal locus (TRL) during instruction with an SLO. Although the readers developed the TRL in about 15 minutes, they read slower with the TRL than the PRL. This TRL research provides promising pilot data.

  16. Escala de Locus de controle ELCO/TELEBRÁS Scale of Locus of control - ELCO

    Directory of Open Access Journals (Sweden)

    Luiz Pasquali

    1998-01-01

    Full Text Available Com base na teoria de Rotter e Escala de Levenson foi elaborada uma escala de Locus de Controle Organizacional (ELCO, composta por 28 itens. A escala foi validada com uma amostra de 350 empregados do Sistema Telebrás. Verificou-se a presença dos 2 fatores previstos na teoria, a saber: internalidade e externalidade, aparecendo a escala de externalidade, com 18 itens, bem estruturada (alfa = 0.81 e a de internalidade, com 10 itens, deixando a desejar no que se refere à consistência interna (alfa = 0.66. Com os dados desta pesquisa foi feita também análise do Locus de Controle desses mesmos empregados. A constatação mais saliente foi a de que o nível de internalidade caiu com o aumento do nível escolar e o aumento da experiência profissional desses mesmos empregados. Estes resultados surpreendentes foram interpretados em termos da situação típica da empresa, que está passando por um período de transição, a saber: a passagem da condição de empresa estatal para empresa privada, o que seria motivo da perda de confiança dos empregados na própria competência, particularmente por parte daqueles com maior competência intelectual e maior experiência profissional. Fez-se igualmente reparos na qualidade psicométrica da escala e da própria teoria do Locus de controle, no sentido de que esta precisa ser melhor axiomatizada para possibilitar a elaboração de escalas mais precisas para a medida dos construtos que propõe.A scale with 28 items, the Organizational Locus of Control (ELCO, was built based on Rotter’s theory and Levenson’s scale. ELCO was validated on a sample of 350 employees of Telebrás, a governmental firm in Brazil. As foreseen from the theory, a principal-axis factoring showed the presence of the expected two factors, namely internal and external locus of control. The external locus of control factor, composed of 18 items, showed good internal consistency (alpha =.81 whereas the internal factor, with 10 items

  17. Low Cost Upper Atmosphere Sounder (LOCUS)

    Science.gov (United States)

    Gerber, Daniel; Swinyard, Bruce M.; Ellison, Brian N.; Aylward, Alan D.; Aruliah, Anasuya; Plane, John M. C.; Feng, Wuhu; Saunders, Christopher; Friend, Jonathan; Bird, Rachel; Linfield, Edmund H.; Davies, A. Giles; Parkes, Steve

    2014-05-01

    near future. We describe the current instrument configuration of LOCUS, and give a first preview of the expected science return such a mission would yield. The LOCUS instrument concept calls for four spectral bands, a first band at 4.7 THz to target atomic oxygen (O), a second band at 3.5 THz to target hydroxyl (OH), a third band at 1.1 THz to cover several diatomic species (NO, CO, O3, H2O) and finally a fourth band at 0.8 THz to retrieve pointing information from molecular oxygen (O2). LOCUS would be the first satellite instrument to measure atomic oxygen on a global scale with a precision that will allow the retrieval of the global O distribution. It would also be the first time that annual and diurnal changes in O are measured. This will be a significant step forward in understanding the chemistry and dynamics of the MLT. Current indications (derived from CRISTA measurement) lead us to believe that current models only give a poor representation of upper atmospheric O. The secondary target species can help us to address additional scientific questions related to both Climate (distribution of climate relevant gases, highly geared cooling of the MLT in response to Climate change, increased occurrence of Polar Mesospheric Clouds (PMC), etc) and Space Weather (precipitation of electrically charged particles and impact on NOx chemistry, fluctuations of solar Lyman-alpha flux through shown in the the distribution of photochemically active species, etc).

  18. EL LOCUS DE DISTRIBUCION COMO COROLARIO DEL LOCUS DE CONTROL (THE LOCUS OF DISTRIBUTION AS A COROLLARY TO THE LOCUS OF CONTROL

    Directory of Open Access Journals (Sweden)

    Mayoral Luisa

    2009-08-01

    Full Text Available Resumen: Este es un artículo científico acerca del Locus de Distribución, surgido de un estudio realizado con una población de docentes y alumnos universitarios. Respecto de los primeros, se ha indagado acerca de las atribuciones que se realizaban en torno a las recompensas y sanciones, que ellos distribuían a sus alumnos.Respecto de los segundos, se ha buscado determinar la valoración que estos realizaban de sus profesores, en términos de aquellas atribuciones. Para ello, se utilizaron dos paradigmas clásicamente empleados para verificar la existencia de una norma: el paradigma de la autopresentación (docentes, y el paradigma de los j uicios (alumnos. La cuestión planteada fue determinar si en el caso de los comportamientos distributivos de refuerzos, las causas se atribuían a variables externas -en particular a los receptores de esos refuerzos- y si esas formas de atribución eran conocidas y valoradas o no, por los alumnos. De los resultados, surgió la confirmación de nuestra hipótesis de explicaciones externas en materia de comportamientos distributivos de sanciones en el ámbito de la docencia y la valoración positiva de estas atribuciones por los alumnos.Abstract:This one is a scientific article brings over of the Locus of Distribution, arisen from a study realized with a population of teachers and university pupils. Respect of the first ones, it has been investigated brings over of the attributions that were concerning around the reinforcements which they were distributing to pupils. Respect of the second ones, one has sought to determine the valuation that these realized of the teachers, in terms of those attributions. For it, two paradigms were in use classic used to check the existence of a norm: the paradigm of the auto-presentation (teachers, and the paradigm of the judgments (pupils The raised question was to determine if in case of the distributive behaviours of reinforcements, the reasons were assuming to external

  19. Locus of control and cerebral asymmetry.

    Science.gov (United States)

    De Brabander, B; Boone, C; Gerits, P

    1992-08-01

    Data about the lack of synchronism of flexor carpi ulnaris peak EMG values of bimanual reactions during a semantic and during a visuospatial discrimination reaction time task are reported. The effects of type of task as well as the presence or absence of an unexpected stimulus preceding the reaction stimulus on lack of synchronism clearly depend upon the locus of control of the subjects, as measured on Rotter's I-E scale. On the basis of several arguments it is proposed that the measure of lack of synchronism reflects in an opposite sense the amount of dopaminergic activation or motor readiness in the sense in which Pribram and McGuinness in 1975 and Tucker and Williamson in 1984 have defined these concepts. The results for 15 women and 18 men show that more internally oriented subjects are more activated by a semantic task and by an unexpected preparatory stimulus in this type of task than more externally oriented subjects. The opposite appears to hold on the visuospatial task and unexpected preparatory stimuli therein. Together with earlier findings about reaction times and a number of relevant findings in the literature, the results are interpreted as indicative of basic differences in asymmetric tonic activation of the cerebral hemispheres between more internally and more externally oriented subjects. A model is proposed to explain phasic activating effects which ensue when tonically more left- or right-activated subjects perform left- or right-hemisphere tasks and when supplementary irrelevant stimuli are received.

  20. THE LOCUS COERULEUS AND CENTRAL CHEMOSENSITIVITY

    Science.gov (United States)

    Gargaglioni, Luciane H.; Hartzler, Lynn K.; Putnam, Robert W.

    2010-01-01

    The locus coeruleus (LC) lies in the dorsal pons and supplies noradrenergic (NA) input to many regions of the brain, including respiratory control areas. The LC may provide tonic input for basal respiratory drive and is involved in central chemosensitivity since focal acidosis of the region stimulates ventilation and ablation reduces CO2-induced increased ventilation. The output of LC is modulated by both serotonergic and glutamatergic inputs. A large percentage of LC neurons are intrinsically activated by hypercapnia. This percentage and the magnitude of their response are highest in young neonates and decrease dramatically after postnatal day P10. The cellular bases for intrinsic chemosensitivity of LC neurons are comprised of multiple factors, primary among them being reduced extracellular and intracellular pH, which inhibit inwardly rectifying and voltage-gated K+ channels, and activate L-type Ca2+ channels. Activation of KCa channels in LC neurons may limit their ultimate response to hypercapnia. Finally, the LC mediates central chemosensitivity and contains pH-sensitive neurons in amphibians, suggesting that the LC has a long-standing phylogenetic role in respiratory control. PMID:20435170

  1. Production of the Escherichia coli common pilus by uropathogenic E. coli is associated with adherence to HeLa and HTB-4 cells and invasion of mouse bladder urothelium.

    Directory of Open Access Journals (Sweden)

    Zeus Saldaña

    Full Text Available Uropathogenic Escherichia coli (UPEC strains cause urinary tract infections and employ type 1 and P pili in colonization of the bladder and kidney, respectively. Most intestinal and extra-intestinal E. coli strains produce a pilus called E. coli common pilus (ECP involved in cell adherence and biofilm formation. However, the contribution of ECP to the interaction of UPEC with uroepithelial cells remains to be elucidated. Here, we report that prototypic UPEC strains CFT073 and F11 mutated in the major pilin structural gene ecpA are significantly deficient in adherence to cultured HeLa (cervix and HTB-4 (bladder epithelial cells in vitro as compared to their parental strains. Complementation of the ecpA mutant restored adherence to wild-type levels. UPEC strains produce ECP upon growth in Luria-Bertani broth or DMEM tissue culture medium preferentially at 26°C, during incubation with cultured epithelial cells in vitro at 37°C, and upon colonization of mouse bladder urothelium ex vivo. ECP was demonstrated on and inside exfoliated bladder epithelial cells present in the urine of urinary tract infection patients. The ability of the CFT073 ecpA mutant to invade the mouse tissue was significantly reduced. The presence of ECP correlated with the architecture of the biofilms produced by UPEC strains on inert surfaces. These data suggest that ECP can potentially be produced in the bladder environment and contribute to the adhesive and invasive capabilities of UPEC during its interaction with the host bladder. We propose that along with other known adhesins, ECP plays a synergistic role in the multi-step infection of the urinary tract.

  2. automatic generation of root locus plots for linear time invariant ...

    African Journals Online (AJOL)

    user

    root locus as a time domain technique for system design and analysis. The Tool Box can also ... theory, it has equally been applied to classical formulation and the ... major constraint, therefore the use of complex graphical ..... The computation.

  3. Y-Chromosome short tandem repeat, typing technology, locus ...

    African Journals Online (AJOL)

    Aghomotsegin

    technology, locus information and allele frequency in different ... DNA can be used to study human evolution. Besides ... STR markers are important for human identification ..... discovery resource for research on human genetic variation.

  4. LOCUS OF CONTROL AND JOB SATISFACTION: PSU EMPLOYEES

    Directory of Open Access Journals (Sweden)

    Lakshman Vijayashree

    2011-11-01

    Full Text Available Previous research studies have demonstrated that internal/external locus of control impacts jobsatisfaction. The present study thus aims to analyze type of locus of control and its relation with jobsatisfaction. The study will be of great help for organization to understand and know what type oflocus of control their employees has and how it has an impact on job satisfaction.The objectives of this study were: 1- To identify the type of Locus of Control (i.e. Internal orExternal present in Public Sector Units (PSU in Bangalore and 2- To analyze the impact of differenttype of Locus of Control on job satisfaction of PSU Employees. Further hypothesis was also set tocheck the relationship between locus of control and job satisfaction. In addition, the relationshipbetween different demographic factors was also examined. The tool used for this study was LocoInventory. The concept of locus of control by Levenson (1972 was used to develop Loco Inventory(Locus of Control in Organization Inventory. The survey used a questionnaire, which had thirty fivestatements which highlights the factors that determine the locus of control and job satisfaction levelof the employees. The Ratio, ANOVA, and Correlation analysis were used as statistical techniquesfor analysis.The results indicate that there is a positive correlation between internal locus of control and jobsatisfaction as well as between External (other locus of control and job satisfaction. And in case ofExternal (Chance locus of control and job satisfaction there exists partial positive correlation. As perthis study Job satisfaction level among the employees is also good as the mean is 17, which is closerto maximum scale value of 25. As per ANOVA table there is a significant variance betweeninternality and age as well as between externality (chance and age. There is no significantrelationship between internality and demographic factors like gender and education. There is nosignificant relationship between

  5. Molecular analysis of the glucocerebrosidase gene locus

    Energy Technology Data Exchange (ETDEWEB)

    Winfield, S.L.; Martin, B.M.; Fandino, A. [Clinical Neuroscience Branch, Bethesda, MD (United States)] [and others

    1994-09-01

    Gaucher disease is due to a deficiency in the activity of the lysosomal enzyme glucocerebrosidase. Both the functional gene for this enzyme and a pseudogene are located in close proximity on chromosome 1q21. Analysis of the mutations present in patient samples has suggested interaction between the functional gene and the pseudogene in the origin of mutant genotypes. To investigate the involvement of regions flanking the functional gene and pseudogene in the origin of mutations found in Gaucher disease, a YAC clone containing DNA from this locus has been subcloned and characterized. The original YAC containing {approximately}360 kb was truncated with the use of fragmentation plasmids to about 85 kb. A lambda library derived from this YAC was screened to obtain clones containing glucocerebrosidase sequences. PCR amplification was used to identify subclones containing 5{prime}, central, or 3{prime} sequences of the functional gene or of the pseudogene. Clones spanning the entire distance from the last exon of the functional gene to intron 1 of the pseudogene, the 5{prime} end of the functional gene and 16 kb of 5{prime} flanking region and approximately 15 kb of 3{prime} flanking region of the pseudogene were sequenced. Sequence data from 48 kb of intergenic and flanking regions of the glucocerebrosidase gene and its pseudogene has been generated. A large number of Alu sequences and several simple repeats have been found. Two of these repeats exhibit fragment length polymorphism. There is almost 100% homology between the 3{prime} flanking regions of the functional gene and the pseudogene, extending to about 4 kb past the termination codons. A much lower degree of homology is observed in the 5{prime} flanking region. Patient samples are currently being screened for polymorphisms in these flanking regions.

  6. Neurolinguistic programming training, trait anxiety, and locus of control.

    Science.gov (United States)

    Konefal, J; Duncan, R C; Reese, M A

    1992-06-01

    Training in the neurolinguistic programming techniques of shifting perceptual position, visual-kinesthetic dissociation, timelines, and change-history, all based on experiential cognitive processing of remembered events, leads to an increased awareness of behavioral contingencies and a more sensitive recognition of environmental cues which could serve to lower trait anxiety and increase the sense of internal control. This study reports on within-person and between-group changes in trait anxiety and locus of control as measured on the Spielberger State-Trait Anxiety Inventory and Wallston, Wallston, and DeVallis' Multiple Health Locus of Control immediately following a 21-day residential training in neurolinguistic programming. Significant with-in-person decreases in trait-anxiety scores and increases in internal locus of control scores were observed as predicted. Chance and powerful other locus of control scores were unchanged. Significant differences were noted on trait anxiety and locus of control scores between European and U.S. participants, although change scores were similar for the two groups. These findings are consistent with the hypothesis that this training may lower trait-anxiety scores and increase internal locus of control scores. A matched control group was not available, and follow-up was unfortunately not possible.

  7. [Health locus of control of patients in disease management programmes].

    Science.gov (United States)

    Schnee, M; Grikscheit, F

    2013-06-01

    Health locus of control beliefs plays a major role in improving self-management skills of the chronically ill - a main goal in disease management programmes (DMP). This study aims at characterising participants in disease management regarding their health locus of control. Data are based on 4 cross-sectional postal surveys between spring and autumn of 2006 and 2007 within the Health Care Monitor of the Bertelsmann Foundation. Among the 6 285 respondents, 1 266 are chronically ill and not enrolled in a DMP and 327 are participating in a DMP. A high internal locus of control (HLC) occurs significantly less often in DMP patients than in normal chronically ill patients (and healthy people) controlling for age, gender and social class. With increasing age, a high internal locus of control is also significantly less likely. When comparing healthy people, the chronically ill and the DMP participants a social gradient of a high internal locus of control belief can be observed. The weaker internal and higher doctor-related external locus of control of DMP participants should be carefully observed by the physician when trying to strengthen the patients' self-management skills. Evaluators of DMP should take into account the different baselines of DMP patients and relevant control groups and incorporate these differences into the evaluation.

  8. Psicologia e Arquitetura: em busca do locus interdisciplinar Psychology and Architecture: looking for the interdisciplinary locus

    Directory of Open Access Journals (Sweden)

    Gleice Azambuja Elali

    1997-12-01

    Full Text Available Partindo do reconhecimento da inevitável interdisciplinaridade no estudo da relação pessoa-ambiente, o artigo discute a Psicologia Ambiental enquanto locus privilegiado na interseção entre Psicologia e Arquitetura, com especial ênfase para a interrelação ambiente construído - comportamento humano. Definindo a escolha dos métodos de pesquisa como fator crucial a esta posição interdisciplinar, o texto aponta os principais métodos atualmente utilizados, facilidades de aplicação e vantagens/desvantagens dos mesmos, defendendo a propriedade do uso de multimétodos na realização de trabalhos na área.Acknowledging interdisciplinarity as an inevitable condition for the study of person-environment relationship, the article discusses Environmental Psychology as locus of intersection between Psychology and Architecture, converging upon the interrelationship human behavior - built environment. Considering that the choice of research methods is an essential element to such an approach, the text defines the main methods and techniques used in this area, their application and advantages/disadvantages, emphasizing a multi-method strategy.

  9. Replication of an Association Between the Lymphoid Tyrosine Phosphatase Locus (LYP/PTPN22) With Type 1 Diabetes, and Evidence for Its Role as a General Autoimmunity Locus

    National Research Council Canada - National Science Library

    Deborah Smyth; Jason D. Cooper; Joanne E. Collins; Joanne M. Heward; Jayne A. Franklyn; Joanna M.M. Howson; Adrian Vella; Sarah Nutland; Helen E. Rance; Lisa Maier; Bryan J. Barratt; Cristian Guja; Constantin Ionescu-Tı̂rgovişte; David A. Savage; David B. Dunger; Barry Widmer; David P. Strachan; Susan M. Ring; Neil Walker; David G. Clayton; Rebecca C.J. Twells; Stephen C.L. Gough; John A. Todd

    2004-01-01

    Replication of an Association Between the Lymphoid Tyrosine Phosphatase Locus ( LYP/PTPN22 ) With Type 1 Diabetes, and Evidence for Its Role as a General Autoimmunity Locus Deborah Smyth 1 , Jason D...

  10. Mutation at the Human D1S80 Minisatellite Locus

    Directory of Open Access Journals (Sweden)

    Kuppareddi Balamurugan

    2012-01-01

    Full Text Available Little is known about the general biology of minisatellites. The purpose of this study is to examine repeat mutations from the D1S80 minisatellite locus by sequence analysis to elucidate the mutational process at this locus. This is a highly polymorphic minisatellite locus, located in the subtelomeric region of chromosome 1. We have analyzed 90,000 human germline transmission events and found seven (7 mutations at this locus. The D1S80 alleles of the parentage trio, the child, mother, and the alleged father were sequenced and the origin of the mutation was determined. Using American Association of Blood Banks (AABB guidelines, we found a male mutation rate of 1.04×10-4 and a female mutation rate of 5.18×10-5 with an overall mutation rate of approximately 7.77×10-5. Also, in this study, we found that the identified mutations are in close proximity to the center of the repeat array rather than at the ends of the repeat array. Several studies have examined the mutational mechanisms of the minisatellites according to infinite allele model (IAM and the one-step stepwise mutation model (SMM. In this study, we found that this locus fits into the one-step mutation model (SMM mechanism in six out of seven instances similar to STR loci.

  11. Inferring Demographic History Using Two-Locus Statistics.

    Science.gov (United States)

    Ragsdale, Aaron P; Gutenkunst, Ryan N

    2017-06-01

    Population demographic history may be learned from contemporary genetic variation data. Methods based on aggregating the statistics of many single loci into an allele frequency spectrum (AFS) have proven powerful, but such methods ignore potentially informative patterns of linkage disequilibrium (LD) between neighboring loci. To leverage such patterns, we developed a composite-likelihood framework for inferring demographic history from aggregated statistics of pairs of loci. Using this framework, we show that two-locus statistics are more sensitive to demographic history than single-locus statistics such as the AFS. In particular, two-locus statistics escape the notorious confounding of depth and duration of a bottleneck, and they provide a means to estimate effective population size based on the recombination rather than mutation rate. We applied our approach to a Zambian population of Drosophila melanogaster Notably, using both single- and two-locus statistics, we inferred a substantially lower ancestral effective population size than previous works and did not infer a bottleneck history. Together, our results demonstrate the broad potential for two-locus statistics to enable powerful population genetic inference. Copyright © 2017 by the Genetics Society of America.

  12. Parenting style, locus of control, and oral hygiene in adolescents.

    Science.gov (United States)

    Aleksejūnienė, Jolanta; Brukienė, Vilma

    2012-01-01

    The aim of the study was to test if variations in oral hygiene levels in adolescents were associated with locus of control and parenting styles after controlling for demographic factors. The study sample comprised 237 adolescents aged 12-13 years. The structured questionnaire included demographic characteristics and items about parenting style and locus of control. The Individual Quantitative Plaque % Index (IQPI) and toothbrushing frequency were used as clinical outcome measures. In the bivariate analyses, socioeconomic status (P=0.012), number of children in the family (P=0.003), and frequency of toothbrushing (P=0.001) were related to dental plaque levels. Gender (Pparenting styles, locus of control, and oral hygiene levels was not confirmed.

  13. Lupus vulgaris occurring in a locus minoris resistentiae.

    Science.gov (United States)

    Long, Richard; Beatch, Anita; Lee, Mao-Cheng; Cheung-Lee, Melody; Wasel, Norman

    2009-01-01

    The pathogenesis of lupus vulgaris, a form of cutaneous tuberculosis, is not always clear, especially in patients who do not have coexistent extracutaneous tuberculosis and in patients with single lesions. To report a case of lupus vulgaris in a locus minoris resistentiae (a site of reduced resistance) and to use a unique set of clinical circumstances and laboratory tests to reconstruct the pathogenesis of the lesion and the response to treatment. Lupus vulgaris can occur in a locus minoris resistentiae; local trauma and possibly other factors, such as increased temperature, topical corticosteroids, and the virulence of the infecting strain, may facilitate the growth of Mycobacterium tuberculosis present at a locus minoris resistentiae as a result of a silent bacillemia.

  14. Desire for control, locus of control, and proneness to depression.

    Science.gov (United States)

    Burger, J M

    1984-03-01

    Two personality constructs, desire for control and locus of control, were related to depression among college students. Measures of levels of depression, desire for control, and locus of control were taken from subjects. Approximately six months later 71% of these subjects returned a questionnaire concerning their experiences with depression during that six-month period. It was found that locus of control scores, particularly the extent to which subjects perceived that their lives were controlled by chance, were significantly related to the depression levels. It was also found that high desire for control subjects who held external perceptions of control were most likely to seek nonprofessional help for depression. In addition, high desire for control subjects who perceived their lives as generally controlled by chance were most likely to have suicidal thoughts. The results are interpreted in terms of a general style that may promote a proneness to depression for certain individuals.

  15. Locus-specific view of flax domestication history.

    Science.gov (United States)

    Fu, Yong-Bi; Diederichsen, Axel; Allaby, Robin G

    2012-01-01

    Crop domestication has been inferred genetically from neutral markers and increasingly from specific domestication-associated loci. However, some crops are utilized for multiple purposes that may or may not be reflected in a single domestication-associated locus. One such example is cultivated flax (Linum usitatissimum L.), the earliest oil and fiber crop, for which domestication history remains poorly understood. Oil composition of cultivated flax and pale flax (L. bienne Mill.) indicates that the sad2 locus is a candidate domestication locus associated with increased unsaturated fatty acid production in cultivated flax. A phylogenetic analysis of the sad2 locus in 43 pale and 70 cultivated flax accessions established a complex domestication history for flax that has not been observed previously. The analysis supports an early, independent domestication of a primitive flax lineage, in which the loss of seed dispersal through capsular indehiscence was not established, but increased oil content was likely occurred. A subsequent flax domestication process occurred that probably involved multiple domestications and includes lineages that contain oil, fiber, and winter varieties. In agreement with previous studies, oil rather than fiber varieties occupy basal phylogenetic positions. The data support multiple paths of flax domestication for oil-associated traits before selection of the other domestication-associated traits of seed dispersal loss and fiber production. The sad2 locus is less revealing about the origin of winter tolerance. In this case, a single domestication-associated locus is informative about the history of domesticated forms with the associated trait while partially informative on forms less associated with the trait.

  16. History of the discovery of a master locus producing piRNAs: the flamenco/COM locus in Drosophila melanogaster

    Directory of Open Access Journals (Sweden)

    Coline eGoriaux

    2014-08-01

    Full Text Available The discovery of transposable elements (TEs in the 1950s by B. McClintock implied the existence of cellular regulatory systems controlling TE activity. The discovery of flam an heterochromatic locus from Drosophila melanogaster and its ability to survey several TEs such as gypsy, ZAM and Idefix contributed to peer deeply into the mechanisms of the genetic and epigenetic regulation of TEs. flam was the first cluster producing small RNAs to be discovered long before RNAi pathways were identified in 1998. As a result of the detailed genetic analyses performed by certain laboratories and of the sophisticated genetic tools they developed, this locus has played a major role in our understanding of piRNA mediated TE repression in animals. Here we review the first discovery of this locus and retrace decades of studies that led to our current understanding of the relationship between genomes and their TE targets.

  17. History of the discovery of a master locus producing piRNAs: the flamenco/COM locus in Drosophila melanogaster.

    Science.gov (United States)

    Goriaux, Coline; Théron, Emmanuelle; Brasset, Emilie; Vaury, Chantal

    2014-01-01

    The discovery of transposable elements (TEs) in the 1950s by B. McClintock implied the existence of cellular regulatory systems controlling TE activity. The discovery of flamenco (flam) an heterochromatic locus from Drosophila melanogaster and its ability to survey several TEs such as gypsy, ZAM, and Idefix contributed to peer deeply into the mechanisms of the genetic and epigenetic regulation of TEs. flam was the first cluster producing small RNAs to be discovered long before RNAi pathways were identified in 1998. As a result of the detailed genetic analyses performed by certain laboratories and of the sophisticated genetic tools they developed, this locus has played a major role in our understanding of piRNA mediated TE repression in animals. Here we review the first discovery of this locus and retrace decades of studies that led to our current understanding of the relationship between genomes and their TE targets.

  18. Thought Recognition, Locus of Control, and Adolescent Well-Being.

    Science.gov (United States)

    Kelley, Thomas M.; Stack, Steven A.

    2000-01-01

    Reviews the underlying assumptions and principles of a new psychological paradigm, Psychology of Mind/Health Realization (POM/HR). Thought recognition is compared with locus of control (LOC). The relationship of LOC to self-reported happiness and satisfaction is examined from the perspective of POM/HR, using a sample of at-risk adolescents…

  19. Confirmatory Factor Analysis of the Work Locus of Control Scale

    Science.gov (United States)

    Oliver, Joseph E.; Jose, Paul E.; Brough, Paula

    2006-01-01

    Original formulations of the Work Locus of Control Scale (WLCS) proposed a unidimensional structure of this measure; however, more recently, evidence for a two-dimensional structure has been reported, with separate subscales for internal and external loci of control. The current study evaluates the one- and two-factor models with confirmatory…

  20. Relationships among Impulsiveness, Locus of Control, Sex, and Music Practice

    Science.gov (United States)

    Miksza, Peter

    2006-01-01

    This study is an investigation of relationships among impulsiveness, locus of control, sex, observed practice behaviors, practice effectiveness, and self-reported practice habits in a sample of 40 college brass players. Practice effectiveness was defined by the amount of change in pretest and posttest performance achievement scores over one…

  1. Locus of Control and Its Reflection in Teachers' Professional Attributions.

    Science.gov (United States)

    Kremer, Lya; Lifmann, Margot

    1982-01-01

    Investigated possible reflections of teachers' locus of control in their professional attributions in educational situations. Findings based on a random sample of 190 elementary school teachers point to significant differences between high and low scores on the I.E. Scale (Rotter, 1966) in attribution of responsibility in several educational…

  2. The Locus of the Focus of a Rolling Parabola

    Science.gov (United States)

    Agarwal, Anurag; Marengo, James

    2010-01-01

    The catenary is usually introduced as the shape assumed by a hanging flexible cable. This is a "physical" description of a catenary. In this article we give a "geometrical" description of a catenary. Specifically we show that the catenary is the locus of the focus of a certain parabola as it rolls on the x-axis.

  3. Exploring Learner Autonomy: Language Learning Locus of Control in Multilinguals

    Science.gov (United States)

    Peek, Ron

    2016-01-01

    By using data from an online language learning beliefs survey (n?=?841), defining language learning experience in terms of participants' multilingualism, and using a domain-specific language learning locus of control (LLLOC) instrument, this article examines whether more experienced language learners can also be seen as more autonomous language…

  4. Should Farmers' Locus of Control Be Used in Extension?

    Science.gov (United States)

    Nuthall, Peter L.

    2010-01-01

    To explore whether Farmers' Locus of Control (LOC) could be useful in agricultural extension programmes to improve managerial ability. This test records a farmer's belief in her/his control over production outcomes. A mail survey of 2300 New Zealand farmers was used to obtain a range of variables, and to measure their LOC using a question set…

  5. Locus of Control and Human Capital Investment Revisited

    Science.gov (United States)

    Cebi, Merve

    2007-01-01

    This paper examines the effect of teenagers' outlooks--specified as their locus of control--on educational attainment and labor market outcomes. I replicate the study of Coleman and DeLeire (2003) and test the predictions of their theoretical model using a different data set--National Longitudinal Survey of Youth (NLSY). The findings fail to…

  6. Single locus complementary sex determination in Hymenoptera : an "unintelligent" design?

    NARCIS (Netherlands)

    Wilgenburg, Ellen van; Driessen, Gerard; Beukeboom, Leo W.

    2006-01-01

    The haplodiploid sex determining mechanism in Hymenoptera (males are haploid, females are diploid) has played an important role in the evolution of this insect order. In Hymenoptera sex is usually determined by a single locus, heterozygotes are female and hemizygotes are male. Under inbreeding,

  7. Inferring relationships between pairs of individuals from locus heterozygosities

    Directory of Open Access Journals (Sweden)

    Spinetti Isabella

    2002-11-01

    Full Text Available Abstract Background The traditional exact method for inferring relationships between individuals from genetic data is not easily applicable in all situations that may be encountered in several fields of applied genetics. This study describes an approach that gives affordable results and is easily applicable; it is based on the probabilities that two individuals share 0, 1 or both alleles at a locus identical by state. Results We show that these probabilities (zi depend on locus heterozygosity (H, and are scarcely affected by variation of the distribution of allele frequencies. This allows us to obtain empirical curves relating zi's to H for a series of common relationships, so that the likelihood ratio of a pair of relationships between any two individuals, given their genotypes at a locus, is a function of a single parameter, H. Application to large samples of mother-child and full-sib pairs shows that the statistical power of this method to infer the correct relationship is not much lower than the exact method. Analysis of a large database of STR data proves that locus heterozygosity does not vary significantly among Caucasian populations, apart from special cases, so that the likelihood ratio of the more common relationships between pairs of individuals may be obtained by looking at tabulated zi values. Conclusions A simple method is provided, which may be used by any scientist with the help of a calculator or a spreadsheet to compute the likelihood ratios of common alternative relationships between pairs of individuals.

  8. Modification of Locus of Control among Rehabilitation Counseling Graduate Students.

    Science.gov (United States)

    Pinkard, Calvin M.; Gross, Pincus

    1984-01-01

    Investigated changes in locus of control orientation during graduate education in rehabilitation counseling by comparing students (N=20) who received experiential training with controls who received didactic training. Results indicated movement toward internality was determined by the types of instruction and the level of the initial external…

  9. Exploring Learner Autonomy: Language Learning Locus of Control in Multilinguals

    Science.gov (United States)

    Peek, Ron

    2016-01-01

    By using data from an online language learning beliefs survey (n?=?841), defining language learning experience in terms of participants' multilingualism, and using a domain-specific language learning locus of control (LLLOC) instrument, this article examines whether more experienced language learners can also be seen as more autonomous language…

  10. Determination of the yield locus by means of temperature measurement

    NARCIS (Netherlands)

    Banabic, D.; Huetink, J.

    2006-01-01

    The paper presents a theoretical background of the thermo-graphical method of determining the yield locus. The analytical expression of the temperature variation of the specimen deformed in the elastic state is determined starting from the first law of thermodynamics. The experimental method for det

  11. Motive to Avoid Success, Locus of Control, and Reinforcement Avoidance.

    Science.gov (United States)

    Katovsky, Walter

    Subjects were four groups of 12 college women, high or low in motive to avoid success (MAS) and locus of control (LC), were reinforced for response A on a fixed partial reinforcement schedule on three concept learning tasks, one task consisting of combined reward and punishment, another of reward only, and one of punishment only. Response B was…

  12. 40 CFR 798.5200 - Mouse visible specific locus test.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 31 2010-07-01 2010-07-01 true Mouse visible specific locus test. 798.5200 Section 798.5200 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) TOXIC...)F1 or (101×C3H)F1 hybrids. Females shall be T stock virgins. (ii) Age. Healthy sexually...

  13. [Drug compliance and health locus of control in schizophrenia].

    Science.gov (United States)

    Combes, C; Feral, F

    2011-05-01

    Schizophrenia is a frequent disorder since it affects about 1% of the general population. Drug compliance, that is to say patients' adherence to their treatment, remains rather poor concerning this disease with, on an average, one patient out of two not complying with his/her medication. Among the factors influencing drug compliance, we focused on patients' beliefs in terms of health control, a concept known as health locus of control. This is a concept that originated from social psychology and derived from the Rotters' original concept of locus of control: it corresponds to the type of connexion established by an individual between subsequent events in the history of his/her disease and internal (personal abilities) or external factors (chance, powerful others). Nowadays, the tridimensional structure of this concept is commonly admitted as being in three dimensions: internality, chance externality and powerful others externality, the latter group being divided between doctors and others. We have assumed that there is a correlation between the degree of drug compliance and the internal and/or doctors' external health locus of control. For this purpose, we have determined the quality of drug compliance by using the Medical Adherence Rating Scale (MARS) and the type of health locus of control by using the Multidimensional Health Locus of Control (MHLC) scale among 65 schizophrenic patients. We have also considered it was important to evaluate patients' insight by using the Amador's scale (Scale of Unawareness of Mental Disorder) because many researchers have established a strong correlation between insight and drug compliance in schizophrenia. Associations between the four dimensions of health locus of control ("internal", "chance external", "others external" and "doctors' external") and drug compliance were assessed by estimating Spearman's rank correlation coefficient (r) and its degree of significance (p). These associations were judged significant at an alpha

  14. The Role of Locus of Control of Reinforcement in Interpersonal Attraction

    Science.gov (United States)

    Nowicki, Stephen, Jr.; Blumberg, Neil

    1975-01-01

    The purpose of the present study was to relate subjects' locus of control orientation to the degree of initial interpersonal attraction expressed toward a stranger who differed from the subjects only in degree of expressed locus of control orientation. (Author)

  15. Evolutionary process of a tetranucleotide microsatellite locus in Acipenseriformes

    Indian Academy of Sciences (India)

    Zhao Jun Shao; Eric Rivals; Na Zhao; Sovan Lek; Jianbo Chang; Patrick Berrebi

    2011-08-01

    The evolutionary dynamics of the tetra-nucleotide microsatellite locus Spl-106 were investigated at the repeat and flanking sequences in 137 individuals of 15 Acipenseriform species, giving 93 homologous sequences, which were detected in 11 out of 15 species. Twenty-three haplotypes of flanking sequences and three distinct types of repeats, type I, type II and type III, were found within these 93 sequences. The MS-Align phylogenetic method, newly applied to microsatellite sequences, permitted us to understand the repeat and flanking sequence evolution of Spl-106 locus. The flanking region of locus Spl-106 was highly conserved among the species of genera Acipenser, Huso and Scaphirhynchus, which diverged about 150 million years ago (Mya). The rate of flanking sequence divergence at the microsatellite locus Spl-106 in sturgeons is between 0.011% and 0.079% with an average at 0.028% per million years. Sequence alignment and phylogenetic trees produced by MS-Align showed that both the flanking and repeat regions can cluster the alleles of different species into Pacific and Atlantic lineages. Our results show a synchronous evolutionary pattern between the flanking and repeat regions. Moreover, the coexistence of different repeat types in the same species, even in the same individual, is probably due to two duplication events encompassing the locus Spl-106 that occurred during the divergence of Pacific lineage. The first occured before the diversification of Pacific species (121–96 Mya) and led to repeat types I and II. The second occurred more recently, just before the speciation of A. sinensis and A. dabryanus (69–10 Mya), and led to repeat type III. Sequences in the same species with different repeat types probably corresponds to paralogous loci. This study sheds a new light on the evolutionary mechanisms that shape the complex microsatellite loci involving different repeat types.

  16. Allele-specific locus binding and genome editing by CRISPR at the p16INK4a locus.

    Science.gov (United States)

    Fujita, Toshitsugu; Yuno, Miyuki; Fujii, Hodaka

    2016-07-28

    The clustered regularly interspaced short palindromic repeats (CRISPR) system has been adopted for a wide range of biological applications including genome editing. In some cases, dissection of genome functions requires allele-specific genome editing, but the use of CRISPR for this purpose has not been studied in detail. In this study, using the p16INK4a gene in HCT116 as a model locus, we investigated whether chromatin states, such as CpG methylation, or a single-nucleotide gap form in a target site can be exploited for allele-specific locus binding and genome editing by CRISPR in vivo. First, we showed that allele-specific locus binding and genome editing could be achieved by targeting allele-specific CpG-methylated regions, which was successful for one, but not all guide RNAs. In this regard, molecular basis underlying the success remains elusive at this stage. Next, we demonstrated that an allele-specific single-nucleotide gap form could be employed for allele-specific locus binding and genome editing by CRISPR, although it was important to avoid CRISPR tolerance of a single nucleotide mismatch brought about by mismatched base skipping. Our results provide information that might be useful for applications of CRISPR in studies of allele-specific functions in the genomes.

  17. Hubungan Antara Locus of Control dengan Social Loafing Mahasiswa pada Tugas Berbasis Kelompok

    OpenAIRE

    Simanjuntak, Priscilla Deborah Rouly

    2017-01-01

    111301096 Penelitian ini bertujuan untuk mengetahui hubungan locus of control dan social loafing mahasiswa pada tugas berbasis kelompok. Hasil penelitian terhadap 300 mahasiswa di lingkungan Universitas Sumatera Utara menunjukkan ada hubungan positif antara locus of control dengan social loafing. Data yang diperoleh dalam penelitian ini menunjukkan bahwa semakin internal locus of control seseorang, maka semakin rendah kecenderungannya untuk mengurangi usaha saat bekerja di ...

  18. On the Relation of Locus of Control and L2 Reading and Writing Achievement

    Science.gov (United States)

    Ghonsooly, Behzad; Shirvan, Majid Elahi

    2011-01-01

    Locus of control, a psychological construct, has been the focus of attention in recent decades. Psychologists have discussed the effect of locus of control on achieving life goals in social/psychological interactions. While learning a foreign language involves both social interactions and psychological processes, the role and relation of locus of…

  19. On the Locus Formed by the Maximum Heights of Projectile Motion with Air Resistance

    Science.gov (United States)

    Hernandez-Saldana, H.

    2010-01-01

    We present an analysis on the locus formed by the set of maxima of the trajectories of a projectile launched in a medium with linear drag. Such a place, the locus of apexes, is written in terms of the Lambert "W" function in polar coordinates, confirming the special role played by this function in the problem. To characterize the locus, a study of…

  20. The active spatial organization of the β-globin locus requires the transcription factor EKLF

    NARCIS (Netherlands)

    R.P.M. Drissen (Roy); R.-J.T.S. Palstra (Robert-Jan); N. Gillemans (Nynke); D. Splinter (Daniël); F.G. Grosveld (Frank); J.N.J. Philipsen (Sjaak); W.L. de Laat (Wouter)

    2004-01-01

    textabstractThree-dimensional organization of a gene locus is important for its regulation, as recently demonstrated for the β-globin locus. When actively expressed, the cis-regulatory elements of the β-globin locus are in proximity in the nuclear space, forming a compartment termed the Active

  1. A cut locus for finite graphs and the farthest point mapping

    DEFF Research Database (Denmark)

    Maddaloni, Alessandro; Zamfirescu, Carol T.

    2016-01-01

    We reflect upon an analogue of the cut locus, a notion classically studied in Differential Geometry, for finite graphs. The cut locus C(x) of a vertex x shall be the graph induced by the set of all vertices y with the property that no shortest path between x and z, z≠y, contains y. The cut locus ...

  2. Rasch Analysis of the Locus-of-Hope Scale. Brief Report

    Science.gov (United States)

    Gadiana, Leny G.; David, Adonis P.

    2015-01-01

    The Locus-of-Hope Scale (LHS) was developed as a measure of the locus-of-hope dimensions (Bernardo, 2010). The present study adds to the emerging literature on locus-of-hope by assessing the psychometric properties of the LHS using Rasch analysis. The results from the Rasch analyses of the four subscales of LHS provided evidence on the…

  3. Externality and locus of control in obese children.

    Science.gov (United States)

    Isbitsky, J R; White, D R

    1981-03-01

    Fifty-nine obese and normal-weight children, aged 8-12 years were compared on two dimensions of "externality," previously examined in obese adults. Significant sex difference indicated that boys generally ate more than girls and held more internal locus of control expectancies. However, obese and normal-weight children were not differentiated by their performance on either a food-related or three nonfood-related measures of external-cue responsiveness, nor by their locus of control expectancies. Furthermore, the various measures were neither strongly nor consistently intercorrelated, providing little support for the notion of a single underlying dimension of "externality." The contribution of physiological, sensory, cognitive-motivational, and sociocultural parameters to the regulation of eating behavior was discussed.

  4. Two-locus inbreeding measures for recurrent selection.

    Science.gov (United States)

    Choy, S C; Weir, B S

    1977-03-01

    For a population undergoing recurrent selection, a method is presented for determining the average inbreeding coefficients at the end of each breeding cycle. The coefficients are derived in terms of probability measures that genes are identical by descent. For the one-locus case, two digametic measures are defined and employed in the derivation of a recurrence formula for the inbreeding coefficient. Two further classes of measures, trigametic and quadrigametic, are required for transition from one cycle to the previous one to allow the calculation of the inbreeding function for the two-locus case. Numerical values of the average probability of double identity by descent for populations with various imposed assumptions are listed to illustrate the effects of linkage and population size on the accrual of inbreeding and hence of homozygosity.

  5. Refined localization of the Prieto-syndrome locus

    Energy Technology Data Exchange (ETDEWEB)

    Martinez, F.; Prieto, F. [Unidad de Genetica, Valencia (Spain); Gal, A. [Universitaets-Krankenhaus Eppendorf, Hamburg (Germany)

    1996-07-12

    PRS designates the locus for a syndromal form of X-linked mental retardation (Prieto syndrome) characterized by minor facial anomalies, ear malformation, abnormal growth of teeth, clinodactyly, sacral dimple, patellar luxation, malformation of lower limbs, abnormalities of the fundus of the eye, and subcortical cerebral atrophy. Linkage analysis localized the disease locus between DXS84 (Xp21.1) and DXS255. Here we present additional linkage data that provide further support and refinement of this localization. Individual III-18 gave birth to a male, currently aged 2 7/12 years, who clearly shows delayed psychomotor development. He began to walk at 23 months and his speech is delayed. In addition, he shows the characteristic facial anomalies, {open_quotes}dysplastic{close_quotes} ears, sacral dimple, and clinodactyly, as do all other affected males in this family. 7 refs., 1 tab.

  6. The locus of microRNA-10b

    Science.gov (United States)

    Biagioni, Francesca; Bossel Ben-Moshe, Noa; Fontemaggi, Giulia; Yarden, Yosef; Domany, Eytan; Blandino, Giovanni

    2013-01-01

    Contemporary microRNA research has led to significant advances in our understanding of the process of tumorigenesis. MicroRNAs participate in different events of a cancer cell’s life, through their ability to target hundreds of putative transcripts involved in almost every cellular function, including cell cycle, apoptosis, and differentiation. The relevance of these small molecules is even more evident in light of the emerging linkage between their expression and both prognosis and clinical outcome of many types of human cancers. This identifies microRNAs as potential therapeutic modifiers of cancer phenotypes. From this perspective, we overview here the miR-10b locus and its involvement in cancer, focusing on its role in the establishment (miR-10b*) and spreading (miR-10b) of breast cancer. We conclude that targeting the locus of microRNA 10b holds great potential for cancer treatment. PMID:23839045

  7. Fine-mapping of an Arabidopsis cell death mutation locus

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    An Arabidopsis cell death mutation locus was mapped to chromosome 2 between IGS1 and mi421. The YAC clone ends, CIC9A3R, CIC11C7L, CIC2G5R and RFLP marker CDs3 within this interval, were used to probe TAMU BAC library and 31 BAC clones were obtained. A BAC contig encompassing the mutation locus, which consists of T6P5, T7M23, T12A21, T8L6 and T18A18, was identified by Southern hybridization with the BAC ends as probes. 11 CAPS and 12 STS markers were developed in this region. These results will facilitate map-based cloning of the genes and sequencing of the genomic DNA in this region.

  8. Fine-mapping of an Arabidopsis cell death mutation locus

    Institute of Scientific and Technical Information of China (English)

    牟中林; 戴亚; 李家洋

    2000-01-01

    An Arabidopsis cell death mutation locus was mapped to chromosome 2 between lGS1 and mi421. The YAC clone ends, CIC9A3R, CIC11C7L, CIC2G5R and RFLP marker CDs3 within this interval, were used to probe TAMU BAC library and 31 BAC clones were obtained. A BAC contig encompassing the mutation locus, which consists of T6P5, T7M23, T12A21, T8L6 and T18A18, was identified by Southern hybridization with the BAC ends as probes. 11 CAPS and 12 STS markers were developed in this region. These results will facilitate map-based cloning of the genes and sequencing of the genomic DNA in this region.

  9. Analysis of the ABCA4 genomic locus in Stargardt disease

    DEFF Research Database (Denmark)

    Zernant, Jana; Xie, Yajing Angela; Ayuso, Carmen

    2014-01-01

    Autosomal recessive Stargardt disease (STGD1, MIM 248200) is caused by mutations in the ABCA4 gene. Complete sequencing of ABCA4 in STGD patients identifies compound heterozygous or homozygous disease-associated alleles in 65-70% of patients and only one mutation in 15-20% of patients. This study...... patients of European-American descent. Defining disease-associated alleles in the ABCA4 locus requires exceptionally well characterized large cohorts and extensive analyses by a combination of various approaches....

  10. Characterization of a Multipeptide Lantibiotic Locus in Streptococcus pneumoniae

    Directory of Open Access Journals (Sweden)

    Natalie Maricic

    2016-01-01

    Full Text Available Bacterial communities are established through a combination of cooperative and antagonistic interactions between the inhabitants. Competitive interactions often involve the production of antimicrobial substances, including bacteriocins, which are small antimicrobial peptides that target other community members. Despite the nearly ubiquitous presence of bacteriocin-encoding loci, inhibitory activity has been attributed to only a small fraction of gene clusters. In this study, we characterized a novel locus (the pld locus in the pathogen Streptococcus pneumoniae that drives the production of a bacteriocin called pneumolancidin, which has broad antimicrobial activity. The locus encodes an unusual tandem array of four inhibitory peptides, three of which are absolutely required for antibacterial activity. The three peptide sequences are similar but appear to play distinct roles in regulation and inhibition. A modification enzyme typically found in loci encoding a class of highly modified bacteriocins called lantibiotics was required for inhibitory activity. The production of pneumolancidin is controlled by a two-component regulatory system that is activated by the accumulation of modified peptides. The locus is located on a mobile element that has been found in many pneumococcal lineages, although not all elements carry the pld genes. Intriguingly, a minimal region containing only the genes required for pneumolancidin immunity was found in several Streptococcus mitis strains. The pneumolancidin-producing strain can inhibit nearly all pneumococci tested to date and provided a competitive advantage in vivo. These peptides not only represent a unique strategy for bacterial competition but also are an important resource to guide the development of new antimicrobials.

  11. Male-pattern baldness susceptibility locus at 20p11.

    NARCIS (Netherlands)

    Richards, J.B.; Yuan, X.; Geller, F.; Waterworth, D.; Bataille, V.; Glass, D.; Song, K.; Waeber, G.; Vollenweider, P.; Aben, K.K.H.; Kiemeney, L.A.L.M.; Walters, B.; Soranzo, N.; Thorsteinsdottir, U.; Kong, A.; Rafnar, T.; Deloukas, P.; Sulem, P.; Stefansson, H.; Stefansson, K.; Spector, T.D.; Mooser, V.

    2008-01-01

    We conducted a genome-wide association study for androgenic alopecia in 1,125 men and identified a newly associated locus at chromosome 20p11.22, confirmed in three independent cohorts (n = 1,650; OR = 1.60, P = 1.1 x 10(-14) for rs1160312). The one man in seven who harbors risk alleles at both 20p1

  12. Male-pattern baldness susceptibility locus at 20p11.

    NARCIS (Netherlands)

    Richards, J.B.; Yuan, X.; Geller, F.; Waterworth, D.; Bataille, V.; Glass, D.; Song, K.; Waeber, G.; Vollenweider, P.; Aben, K.K.H.; Kiemeney, L.A.L.M.; Walters, B.; Soranzo, N.; Thorsteinsdottir, U.; Kong, A.; Rafnar, T.; Deloukas, P.; Sulem, P.; Stefansson, H.; Stefansson, K.; Spector, T.D.; Mooser, V.

    2008-01-01

    We conducted a genome-wide association study for androgenic alopecia in 1,125 men and identified a newly associated locus at chromosome 20p11.22, confirmed in three independent cohorts (n = 1,650; OR = 1.60, P = 1.1 x 10(-14) for rs1160312). The one man in seven who harbors risk alleles at both 20p1

  13. Recent Advances of Flowering Locus T Gene in Higher Plants

    OpenAIRE

    Shuiyuan Cheng; Feng Xu; Xiaofeng Rong; Xiaohua Huang

    2012-01-01

    Flowering Locus T (FT) can promote flowering in the plant photoperiod pathway and also facilitates vernalization flowering pathways and other ways to promote flowering. The expression of products of the FT gene is recognized as important parts of the flowering hormone and can induce flowering by long-distance transportation. In the present study, many FT-like genes were isolated, and the transgenic results show that FT gene can promote flowering in plants. This paper reviews the progress of t...

  14. Pressure sore survey. Part 3: Locus of control.

    Science.gov (United States)

    Maylor, M; Torrance, C

    1999-03-01

    This is the third in a three-part article which investigates the prevalence, knowledge and attitudes to pressure sores in one NHS trust. This study describes the methodology used in choosing and developing attitude scales to explore whether there are any relationships between the locus of control and pressure sore prevention. Factors to do with attitude and the value associated with pressure sore prevention have a central role. Attitudes and beliefs affect what we do and may contribute to pressure sore development.

  15. The pgm locus and pigmentation phenotype in Yersinia pestis

    Directory of Open Access Journals (Sweden)

    Tereza Cristina Leal-Balbino

    2006-01-01

    Full Text Available The pigmentation (pgm locus is a large unstable area of the Yersinia pestis chromosome composed of a segment of iron acquisition (HPI linked to a pigmentation segment. In this work we examined the mobility of HPI and the pigmentation segment in three Y. pestis isolates using successive subcultures on Congo red agar (CRA plates. Strain P. CE 882 was shown to be highly stable while strains P. Exu 340 and P. Peru 375 dissociated into several phenotypes, PCR analysis showing evidence of changes in the pgm locus of the derived cultures. Strains P. Exu 340 and P. Peru 375 produced previously unreported cultures positive for the pesticin/yersiniabactin outer membrane receptor (psn+ but negative for the iron-regulated protein (irp2-, suggesting the occurrence of rearrangements in this chromosomal region and either a sequential loss or the loss of separated segments. These results provide evidence that besides deletion en bloc, specific rearrangements are also involved in the deletion events for that locus.

  16. Calcium binding properties of the Kingella kingae PilC1 and PilC2 proteins have differential effects on type IV pilus-mediated adherence and twitching motility.

    Science.gov (United States)

    Porsch, Eric A; Johnson, Michael D L; Broadnax, Angela D; Garrett, Christopher K; Redinbo, Matthew R; St Geme, Joseph W

    2013-02-01

    Kingella kingae is an emerging bacterial pathogen that is being recognized increasingly as an important etiology of septic arthritis, osteomyelitis, and bacteremia, especially in young children. The pathogenesis of K. kingae disease begins with bacterial adherence to respiratory epithelium, which is dependent on type IV pili and is influenced by two PilC-like proteins called PilC1 and PilC2. Production of either PilC1 or PilC2 is necessary for K. kingae piliation and bacterial adherence. In this study, we set out to further investigate the role of PilC1 and PilC2 in type IV pilus-associated phenotypes. We found that PilC1 contains a functional 9-amino-acid calcium-binding (Ca-binding) site with homology to the Pseudomonas aeruginosa PilY1 Ca-binding site and that PilC2 contains a functional 12-amino-acid Ca-binding site with homology to the human calmodulin Ca-binding site. Using targeted mutagenesis to disrupt the Ca-binding sites, we demonstrated that the PilC1 and PilC2 Ca-binding sites are dispensable for piliation. Interestingly, we showed that the PilC1 site is necessary for twitching motility and adherence to Chang epithelial cells, while the PilC2 site has only a minor influence on twitching motility and no influence on adherence. These findings establish key differences in PilC1 and PilC2 function in K. kingae and provide insights into the biology of the PilC-like family of proteins.

  17. The Live Attenuated Cholera Vaccine CVD 103-HgR Primes Responses to the Toxin-Coregulated Pilus Antigen TcpA in Subjects Challenged with Wild-Type Vibrio cholerae.

    Science.gov (United States)

    Mayo-Smith, Leslie M; Simon, Jakub K; Chen, Wilbur H; Haney, Douglas; Lock, Michael; Lyon, Caroline E; Calderwood, Stephen B; Kirkpatrick, Beth D; Cohen, Mitchell; Levine, Myron M; Gurwith, Marc; Harris, Jason B

    2017-01-01

    One potential advantage of live attenuated bacterial vaccines is the ability to stimulate responses to antigens which are only expressed during the course of infection. To determine whether the live attenuated cholera vaccine CVD 103-HgR (Vaxchora) results in antibody responses to the in vivo-induced toxin-coregulated pilus antigen TcpA, we measured IgA and IgG responses to Vibrio cholerae O1 El Tor TcpA in a subset of participants in a recently reported experimental challenge study. Participants were challenged with V. cholerae O1 El Tor Inaba N16961 either 10 days or 90 days after receiving the vaccine or a placebo. Neither vaccination nor experimental infection with V. cholerae alone resulted in a robust TcpA IgG or IgA response, but each did elicit a strong response to cholera toxin. However, compared to placebo recipients, vaccinees had a marked increase in IgG TcpA antibodies following the 90-day challenge, suggesting that vaccination with CVD 103-HgR resulted in priming for a subsequent response to TcpA. No such difference between vaccine and placebo recipients was observed for volunteers challenged 10 days after vaccination, indicating that this was insufficient time for vaccine-induced priming of the TcpA response. The priming of the response to TcpA and potentially other antigens expressed in vivo by attenuated V. cholerae may have relevance to the maintenance of immunity in areas where cholera is endemic.

  18. Genome-wide association study identifies a single major locus contributing to survival into old age; the APOE locus revisited

    DEFF Research Database (Denmark)

    Deelen, Joris; Beekman, Marian; Uh, Hae-Won

    2011-01-01

    there was only moderate linkage disequilibrium between rs2075650 and the ApoE ε4 defining SNP rs429358, we could not find an APOE-independent effect of rs2075650 on longevity, either in cross-sectional or in longitudinal analyses. As expected, rs429358 associated with metabolic phenotypes in the offspring...... the deleterious effects of the ApoE ε4 allele. No other major longevity locus was found....

  19. Locus de Controle e escolha do método anticoncepcional Locus de Control y método anticonceptivo elegido Locus of Control and choice of contraceptive method

    Directory of Open Access Journals (Sweden)

    Aline Salheb Alves

    2007-06-01

    Full Text Available Objetivou-se avaliar a relação entre o Locus de Controle e o tipo de método contraceptivo escolhido. Foi utilizada a Escala Multidimensional de Locus de Controle de Levenson e entrevistadas 191 mulheres. As usuárias de preservativo masculino apresentaram maior Internalidade do que as usuárias de injetável mensal. Quanto ao locus Externalidade Outros Poderosos, as usuárias de implante apresentavam menor externalidade do que as usuárias de preservativo masculino, laqueadura, injetável trimestral e DIU. Considerando-se o locus Externalidade Acaso, as usuárias de implante apresentaram menores escores do que as mulheres que optaram pela laqueadura, injetável trimestral e DIU. Observou-se ainda, menor Externalidade Acaso entre as usuárias de injetável mensal em relação às mulheres que fizeram opção pelo injetável trimestral.El objetivo es validar la relación entre el Locus de Control y el tipo de método anticonceptivo elegido. Fue usada la Escala Multidimensional de Locus de Control de Levenson. Fueron entrevistadas 191 mujeres. Las usuarias de condón masculino presentaron Internalidad más grande que las usuarias de inyectable mensual. Considerado el Locus Externalidad - Otro poderoso, las usuarias de implante presentaron menor externalidad de que las usuarias de condón masculino, laqueadura, inyectable trimestral y DIU. Considerado el Locus Externalidad - Quizá, las usuarias del implante presentaron menores resultados que las mujeres que eligieron por la laqueadura, inyectable trimestral y DIU. Se observo que las mujeres usuarias de inyectable mensual presentaron menor Externalidad - Quizá que las mujeres usuarias de inyectable trimestral.The purpose was to assess the relationship between locus of control and the contraceptive method chosen. It was used the Levenson's Multidimensional Locus of Control Scale and 191 women was interviewed. Users of male condoms presented greater Internality than the monthly contraceptive

  20. The construction of a normative scale of locus of control

    Directory of Open Access Journals (Sweden)

    Johann M. Schepers

    2005-10-01

    Full Text Available The primary objective of the study was to construct a normative scale of locus of control for use with students and adults. A corollary of the study was to establish the personality, interest and cognitive correlates of locus of control. Conceptually the instrument is based on attribution theory and on social learning theory. The first edition of the Locus of Control Inventory (LCI was applied to 356 first-year university students during 1994. A factor analysis of the 65 items of the inventory yielded three factors. The factors were interpreted as Autonomy, Internal Control and External Control. Three scales, corresponding to the three factors, were constructed, and yielded reliability coefficients of 0,80; 0,77 and 0,81 respectively. Following this the cognitive, interest and personality correlates of the LCI were determined. The implications of the findings are discussed. Opsomming Die hoofdoel van die studie was die konstruksie van ’n normatiewe skaal van lokus van beheer vir gebruik met studente en volwassenes. ’n Newe-doelwit van die studie was om die persoonlikheids-, belangstellings- en kognitiewe korrelate van lokus van beheer te bepaal. Konseptueel is die instrument op attribusieteorie en sosiale-leerteorie gebaseer. Die eerste-uitgawe van die Lokus van Beheervraelys (LvB is op 356 eerstejaaruniversiteitstudente toegepas gedurende 1994. ’n Faktorontleding van die 65 items van die vraelys is gedoen en het drie faktore opgelewer. Die faktore is as Outonomie, Interne Beheer en Eksterne Beheer geïnterpreteer. Voorts is drie skale wat ooreenstem met die drie faktore, gekonstrueer en het betroubaarhede van 0,80; 0,77 en 0,81, onderskeidelik, opgelewer. Vervolgens is die kognitiewe, belangstellings- en persoonlikheidskorrelate van die LvB bepaal. Die implikasies van die bevindinge word bespreek.

  1. Gene amplification of the Hps locus in Glycine max

    Directory of Open Access Journals (Sweden)

    Kuflu Kuflom

    2006-03-01

    Full Text Available Abstract Background Hydrophobic protein from soybean (HPS is an 8 kD cysteine-rich polypeptide that causes asthma in persons allergic to soybean dust. HPS is synthesized in the pod endocarp and deposited on the seed surface during development. Past evidence suggests that the protein may mediate the adherence or dehiscence of endocarp tissues during maturation and affect the lustre, or glossiness of the seed surface. Results A comparison of soybean germplasm by genomic DNA blot hybridization shows that the copy number and structure of the Hps locus is polymorphic among soybean cultivars and related species. Changes in Hps gene copy number were also detected by comparative genomic DNA hybridization using cDNA microarrays. The Hps copy number polymorphisms co-segregated with seed lustre phenotype and HPS surface protein in a cross between dull- and shiny-seeded soybeans. In soybean cultivar Harosoy 63, a minimum of 27 ± 5 copies of the Hps gene were estimated to be present in each haploid genome. The isolation and analysis of genomic clones indicates that the core Hps locus is comprised of a tandem array of reiterated units, with each 8.6 kb unit containing a single HPS open reading frame. Conclusion This study shows that polymorphisms at the Hps locus arise from changes in the gene copy number via gene amplification. We present a model whereby Hps copy number modulates protein expression levels and seed lustre, and we suggest that gene amplification may result from selection pressures imposed on crop plants.

  2. The barley Frost resistance-H2 locus.

    Science.gov (United States)

    Pasquariello, Marianna; Barabaschi, Delfina; Himmelbach, Axel; Steuernagel, Burkhard; Ariyadasa, Ruvini; Stein, Nils; Gandolfi, Francesco; Tenedini, Elena; Bernardis, Isabella; Tagliafico, Enrico; Pecchioni, Nicola; Francia, Enrico

    2014-03-01

    Frost resistance-H2 (Fr-H2) is a major QTL affecting freezing tolerance in barley, yet its molecular basis is still not clearly understood. To gain a better insight into the structural characterization of the locus, a high-resolution linkage map developed from the Nure × Tremois cross was initially implemented to map 13 loci which divided the 0.602 cM total genetic distance into ten recombination segments. A PCR-based screening was then applied to identify positive bacterial artificial chromosome (BAC) clones from two genomic libraries of the reference genotype Morex. Twenty-six overlapping BACs from the integrated physical-genetic map were 454 sequenced. Reads assembled in contigs were subsequently ordered, aligned and manually curated in 42 scaffolds. In a total of 1.47 Mbp, 58 protein-coding sequences were identified, 33 of which classified according to similarity with sequences in public databases. As three complete barley C-repeat Binding Factors (HvCBF) genes were newly identified, the locus contained13 full-length HvCBFs, four Related to AP2 Triticeae (RAPT) genes, and at least five CBF pseudogenes. The final overall assembly of Fr-H2 includes more than 90 % of target region: all genes were identified along the locus, and a general survey of Repetitive Elements obtained. We believe that this gold-standard sequence for the Morex Fr-H2 will be a useful genomic tool for structural and evolutionary comparisons with Fr-H2 in winter-hardy cultivars along with Fr-2 of other Triticeae crops.

  3. Burnout, locus de control y deportistas de alto rendimiento

    OpenAIRE

    Medina Mojena, Greisy; García Ucha, Francisco Enrique

    2002-01-01

    Los estudios sobre burnout comenzaron en los 70 por Freudenberg (1974) y en los 80 en el deporte. En Cuba este es de los primeros sobre el tema. Se estudiaron 40 deportistas de alto rendimiento de pesas, balonmano, baloncesto y tackewondo. Con una edad entre los 18 y 28 años y experiencia deportiva entre 5 y 16 años. Las técnicas utilizadas son una adaptación, de Garcés de Los Fayos (1999) del Maslach Burnout Inventory (1981) y un test de Locus de control. Los principales resultados c...

  4. Measurement of supernatural belief: sex differences and locus of control.

    Science.gov (United States)

    Randall, T M; Desrosiers, M

    1980-10-01

    Although we live in an age dominated by science and technology, there exists an increasingly popular anti-science sentiment. This study describes the development of a scale to assess the degree of personal acceptance of supernatural causality versus acceptance of scientific explanation. In addition to the psychometric data concerning validity and reliability of the scale, data are presented which showed the personality factor of supernaturalism to be independent of orthodox religious attitudes. Results indicated a significantly greater supernatural acceptance for women, and a positive relation of supernaturalism with external locus of control.

  5. Recent advances of flowering locus T gene in higher plants.

    Science.gov (United States)

    Xu, Feng; Rong, Xiaofeng; Huang, Xiaohua; Cheng, Shuiyuan

    2012-01-01

    Flowering Locus T (FT) can promote flowering in the plant photoperiod pathway and also facilitates vernalization flowering pathways and other ways to promote flowering. The expression of products of the FT gene is recognized as important parts of the flowering hormone and can induce flowering by long-distance transportation. In the present study, many FT-like genes were isolated, and the transgenic results show that FT gene can promote flowering in plants. This paper reviews the progress of the FT gene and its expression products to provide meaningful information for further studies of the functions of FT genes.

  6. Locus of control and its relationship with mental health and adjustment among adolescent females

    Directory of Open Access Journals (Sweden)

    Madhu Jain

    2015-01-01

    Full Text Available Objective: There exists a plethora of researches which have identified the role of Locus of Control in maintaining sound mental health and adjustment. The present study examined the relationship of Locus of Control with Mental Health & overall Adjustment among adolescent females. Method: The participants consisted of 50 adolescent females. Mental Health Battery designed by Singh, Gupta (2000, Rotter′s Locus of Control Scale (1966 & Adjustment Inventory for College Students by Sinha & Singh (1995 were administered. Findings: The findings of the study revealed that adolescent females who possess internal locus of control showed better mental health & overall adjustment pattern which includes home, social, emotional, educational domains and health adjustment domain than those who possess external locus of control. Conclusion: The study highlights the pervasive influence of internal & external locus of control on mental health & adjustment among adolescent females.

  7. A Complete Enumeration and Classification of Two-Locus Disease Models

    CERN Document Server

    Li, W; Li, Wentian; Reich, Jens

    1999-01-01

    There are 512 two-locus, two-allele, two-phenotype, fully-penetrant disease models. Using the permutation between two alleles, between two loci, and between being affected and unaffected, one model can be considered to be equivalent to another model under the corresponding permutation. These permutations greatly reduce the number of two-locus models in the analysis of complex diseases. This paper determines the number of non-redundant two-locus models (which can be 102, 100, 96, 51, 50, or 48, depending on which permutations are used, and depending on whether zero-locus and single-locus models are excluded). Whenever possible, these non-redundant two-locus models are classified by their property. Besides the familiar features of multiplicative models (logical AND), heterogeneity models (logical OR), and threshold models, new classifications are added or expanded: modifying-effect models, logical XOR models, interference and negative interference models (neither dominant nor recessive), conditionally dominant/...

  8. Locus de control y conocimiento, actitud y práctica contraceptivas entre adolescentes universitarios

    OpenAIRE

    Aline Salheb Alves; Maria Helena Baena de Moraes Lopes

    2010-01-01

    OBJECTIVE: To assess the relationship between locus of control and knowledge, attitude and practice regarding pill and condom use among university students. METHODS: The inquiry was developed in Campinas, a city in Southeastern Brazil, in 2006. A total of 295 adolescent newcomers to a public university answered a structured questionnaire and Levenson's multidimensional locus of control scale. The scores of the dimensions of locus of control were calculated and Spearman's correlation coefficie...

  9. Locus ceruleus neurons in people with autism contain no histochemically-detectable mercury

    OpenAIRE

    2015-01-01

    Exposure to environmental mercury has been proposed to play a part in autism. Mercury is selectively taken up by the human locus ceruleus, a region of the brain that has been implicated in autism. We therefore looked for the presence of mercury in the locus ceruleus of people who had autism, using the histochemical technique of autometallography which can detect nanogram amounts of mercury in tissues. In addition, we sought evidence of damage to locus ceruleus neurons in autism by immunostain...

  10. A locus-wide approach to assessing variation in the avian MHC: the B-locus of the wild turkey.

    Science.gov (United States)

    Chaves, L D; Faile, G M; Hendrickson, J A; Mock, K E; Reed, K M

    2011-07-01

    Studies of major histocompatibility complex (MHC) diversity in non-model vertebrates typically focus on structure and sequence variation in the antigen-presenting loci: the highly variable and polymorphic class I and class IIB genes. Although these studies provide estimates of the number of genes and alleles/locus, they often overlook variation in functionally related and co-inherited genes important in the immune response. This study utilizes the sequence of the MHC B-locus derived from a commercial turkey to investigate MHC variation in wild birds. Sequences were obtained for nine interspersed MHC amplicons (non-class I/II) from each of 40 birds representing 3 subspecies of wild turkey (Meleagris gallopavo). Analysis of aligned sequences identified 238 single-nucleotide variants approximately one-third of which had minor allele frequencies >0.2 in the sampled birds. PHASE analysis identified 70 prospective MHC haplotypes in the wild turkeys, whereas a combined analysis with commercial birds identified almost 100 haplotypes in the species. Denaturing gradient gel electrophoresis (DGGE) of the class IIB loci was used to test the efficacy of single-nucleotide polymorphism (SNP) haplotyping to capture locus-wide variation. Diversity in SNP haplotypes and haplotype sharing among individuals was directly reflected in the DGGE patterns. Utilization of a reference haplotype to sequence interspersed regions of the MHC has significant advantages over other methods of surveying diversity while identifying high-frequency SNPs for genotyping. SNP haplotyping provides a means to identify both divergent haplotypes and homozygous individuals for assessment of immunological variation in wild and domestic populations.

  11. Mox: a novel modifier of the tomato Xa locus.

    Science.gov (United States)

    Peterson, P W; Yoder, J I

    1995-01-01

    We have isolated a novel mutation that caused variegated leaf color in a tomato plant which had multiple maize Ac transposable elements and the tomato Xa allele. Xa is a previously characterized semi-dominant mutation that causes tomato leaves to be bright yellow when heterozygous (Xa/xa+). The mutation responsible for the new phenotype was named Mox (Modifier of Xa). The Mox mutation modified the Xa/xa+ yellow leaf phenotype in two ways: it compensated for the Xa allele resulting in a plant with a wildtype green color, and it caused somatic variegation which appeared as white and yellow sectors on the green background. Somatic variegation was visible only if the plant contained both the Mox and Xa loci. Genetic studies indicated that the Mox locus was linked in repulsion to Xa and that the Mox locus was genetically transmitted at a reduced frequency through the male gamete. Molecular characterization of the Ac elements in lines segregating for Mox identified an Ac insertion that appeared to cosegregate with Mox variegation. We propose a model in which the Mox mutation consists of a duplication of the xa+ allele and subsequent Ac-induced breakage of the duplicated region causes variegation.

  12. Synaptic potentials in locus coeruleus neurons in brain slices.

    Science.gov (United States)

    Williams, J T; Bobker, D H; Harris, G C

    1991-01-01

    Neurons of the locus coeruleus (LC) fire action potentials spontaneously in vitro in the absence of any stimulation. This spontaneous activity is thought to arise from intrinsic membrane properties that include a balance between at least two ion conductances. One is a persistent inward sodium current that is active near the threshold for action potential generation. The second is a calcium-dependent potassium current that is activated following the entry of calcium during the action potential, is responsible for the after-hyperpolarization following the action potential, and decays over a period of 1-2 sec following the action potential. The spontaneous activity of LC neurons can be altered by both excitatory and inhibitory synaptic inputs. One excitatory input has been described that is mediated by glutamate receptors of both the non-NMDA and NMDA subtypes. Inhibitory synaptic potentials include those mediated by GABA (acting on GABAA-receptors), glycine (acting on a strychnine-sensitive receptor) and noradrenaline (acting on alpha 2-adrenoceptors). The presence of synaptic potentials mediated by these transmitters, studied in vitro, correlate with studies made in vivo and with histochemical identification of synaptic inputs to the locus coeruleus.

  13. Variation at the TERT locus and predisposition for cancer.

    Science.gov (United States)

    Baird, Duncan M

    2010-05-18

    Telomerase and the control of telomere length are intimately linked to the process of tumourigenesis in humans. Here I review the evidence that variation at the 5p15.33 locus, which contains the TERT gene (encoding the catalytic subunit of telomerase), might play a role in the determination of cancer risk. Mutations in the coding regions of TERT can affect telomerase activity and telomere length, and create severe clinical phenotypes, including bone marrow failure syndromes and a substantive increase in cancer frequency. Variants within the TERT gene have been associated with increased risk of haematological malignancies, including myelodysplastic syndrome and acute myeloid leukaemia as well as chronic lymphocytic leukaemia. Furthermore, there is good evidence from a number of independent genome-wide association studies to implicate variants at the 5p15.33 locus in cancer risk at several different sites: lung cancer, basal cell carcinoma and pancreatic cancer show strong associations, while bladder, prostate and cervical cancer and glioma also show risk alleles in this region. Thus, multiple independent lines of evidence have implicated variation in the TERT gene as a risk factor for cancer. The mechanistic basis of these risk variants is yet to be established; however, the basic biology suggests that telomere length control is a tantalising candidate mechanism underlying cancer risk.

  14. Thought recognition, locus of control, and adolescent well-being.

    Science.gov (United States)

    Kelley, T M; Stack, S A

    2000-01-01

    This paper reviews the underlying assumptions and principles of a new psychological paradigm, Psychology of Mind/Health Realization (POM/HR). A core concept of POM/HR, thought recognition, is then compared with locus of control (LOC), a well-known psychological construct. Next, the relationship of LOC to self-reported happiness and satisfaction is examined from the perspective of POM/HR, using a sample of 1,872 at-risk adolescents from 17 nations. The findings support POM/HR predictions that (1) locus of control would account for a slight portion of the variance in adolescent happiness and satisfaction, (2) circumstances that are external in nature would account for additional variance in happiness and satisfaction, and (3) there would be little difference in self-reported happiness and satisfaction between adolescents self-reporting high and low internal LOC. Further, it was conjectured that the adolescents mistook superficial emotions, such as excitement and security, for genuine feelings of well-being. Finally, the implications for prevention and intervention efforts with at-risk adolescents are discussed.

  15. Cynomolgus macaque (Macaca fascicularis) immunoglobulin heavy chain locus description.

    Science.gov (United States)

    Yu, Guo-Yun; Mate, Suzanne; Garcia, Karla; Ward, Michael D; Brueggemann, Ernst; Hall, Matthew; Kenny, Tara; Sanchez-Lockhart, Mariano; Lefranc, Marie-Paule; Palacios, Gustavo

    2016-07-01

    Cynomolgus macaques (Macaca fascicularis) have become an important animal model for biomedical research. In particular, it is the animal model of choice for the development of vaccine candidates associated with emerging dangerous pathogens. Despite their increasing importance as animal models, the cynomolgus macaque genome is not fully characterized, hindering molecular studies for this model. More importantly, the lack of knowledge about the immunoglobulin (IG) locus organization directly impacts the analysis of the humoral response in cynomolgus macaques. Recent advances in next generation sequencing (NGS) technologies to analyze IG repertoires open the opportunity to deeply characterize the humoral immune response. However, the IG locus organization for the animal is required to completely dissect IG repertoires. Here, we describe the localization and organization of the rearranging IG heavy (IGH) genes on chromosome 7 of the cynomolgus macaque draft genome. Our annotation comprises 108 functional genes which include 63 variable (IGHV), 38 diversity (IGHD), and 7 joining (IGHJ) genes. For validation, we provide RNA transcript data for most of the IGHV genes and all of the annotated IGHJ genes, as well as proteomic data to validate IGH constant genes. The description and annotation of the rearranging IGH genes for the cynomolgus macaques will significantly facilitate scientific research. This is particularly relevant to dissect the immune response during vaccination or infection with dangerous pathogens such as Ebola, Marburg and other emerging pathogens where non-human primate models play a significant role for countermeasure development.

  16. Single locus complementary sex determination in Hymenoptera: an "unintelligent" design?

    Directory of Open Access Journals (Sweden)

    Driessen Gerard

    2006-01-01

    Full Text Available Abstract The haplodiploid sex determining mechanism in Hymenoptera (males are haploid, females are diploid has played an important role in the evolution of this insect order. In Hymenoptera sex is usually determined by a single locus, heterozygotes are female and hemizygotes are male. Under inbreeding, homozygous diploid and sterile males occur which form a genetic burden for a population. We review life history and genetical traits that may overcome the disadvantages of single locus complementary sex determination (sl-CSD. Behavioural adaptations to avoid matings between relatives include active dispersal from natal patches and mating preferences for non-relatives. In non-social species, temporal and spatial segregation of male and female offspring reduces the burden of sl-CSD. In social species, diploid males are produced at the expense of workers and female reproductives. In some social species, diploid males and diploid male producing queens are killed by workers. Diploid male production may have played a role in the evolution or maintenance of polygyny (multiple queens and polyandry (multiple mating. Some forms of thelytoky (parthenogenetic female production increase homozygosity and are therefore incompatible with sl-CSD. We discuss a number of hypothetical adaptations to sl-CSD which should be considered in future studies of this insect order.

  17. Geographic distribution of haplotype diversity at the bovine casein locus

    Directory of Open Access Journals (Sweden)

    Moazami-Goudarzi Katy

    2004-03-01

    Full Text Available Abstract The genetic diversity of the casein locus in cattle was studied on the basis of haplotype analysis. Consideration of recently described genetic variants of the casein genes which to date have not been the subject of diversity studies, allowed the identification of new haplotypes. Genotyping of 30 cattle breeds from four continents revealed a geographically associated distribution of haplotypes, mainly defined by frequencies of alleles at CSN1S1 and CSN3. The genetic diversity within taurine breeds in Europe was found to decrease significantly from the south to the north and from the east to the west. Such geographic patterns of cattle genetic variation at the casein locus may be a result of the domestication process of modern cattle as well as geographically differentiated natural or artificial selection. The comparison of African Bos taurus and Bos indicus breeds allowed the identification of several Bos indicus specific haplotypes (CSN1S1*C-CSN2*A2-CSN3*AI/CSN3*H that are not found in pure taurine breeds. The occurrence of such haplotypes in southern European breeds also suggests that an introgression of indicine genes into taurine breeds could have contributed to the distribution of the genetic variation observed.

  18. The discovery of the microphthalmia locus and its gene, Mitf.

    Science.gov (United States)

    Arnheiter, Heinz

    2010-12-01

    The history of the discovery of the microphthalmia locus and its gene, now called Mitf, is a testament to the triumph of serendipity. Although the first microphthalmia mutation was discovered among the descendants of a mouse that was irradiated for the purpose of mutagenesis, the mutation most likely was not radiation induced but occurred spontaneously in one of the parents of a later breeding. Although Mitf might eventually have been identified by other molecular genetic techniques, it was first cloned from a chance transgene insertion at the microphthalmia locus. And although Mitf was found to encode a member of a well-known transcription factor family, its analysis might still be in its infancy had Mitf not turned out to be of crucial importance for the physiology and pathology of many distinct organs, including eye, ear, immune system, bone, and skin, and in particular for melanoma. In fact, near seven decades of Mitf research have led to many insights about development, function, degeneration, and malignancies of a number of specific cell types, and it is hoped that these insights will one day lead to therapies benefitting those afflicted with diseases originating in these cell types.

  19. Allelism of Genes in the Ml-a locus

    DEFF Research Database (Denmark)

    Giese, Nanna Henriette; Jensen, Hans Peter; Jørgensen, Jørgen Helms

    1980-01-01

    Seven barley lines or varieties, each with a different gene at the Ml-a locus for resistance to Erysiphe graminis were intercrossed. Progeny testing of the F2s using two different fungal isolates per cross provided evidence that there are two or more loci in the Ml-a region. Apparent recombinants...... were also screened for recombination between the Hor1 and Hor2 loci which are situated either side of the Ml-a locus. The cross between Ricardo and Iso42R (Rupee) yielded one possible recombinant, with Ml-a3 and Ml-a(Rul) in the coupling phase; other recombinants had wild-type genes in the coupling...... phase. Iso20R, derived from Hordeum spontaneum 'H204', carrying Ml-a6, had an additional gene, in close coupling with Ml-a6, tentatively named Ml-aSp2 or Reglv, causing an intermediate infection type with isolate EmA30. It is suggested that Ml-a(Ar) in Emir and Ml-a(Rul), shown to differ from other Ml...

  20. Association of Five SNPs at the PARK16 locus as a Susceptibility Locus with Parkinson's Disease for Forensic Application

    Institute of Scientific and Technical Information of China (English)

    CUI Hong-gang; TIAN Xiao-fei; LUO Xiao-guang; LI Feng-rui; ZHU Lan-hui; ZHOU Yi-shu; REN Yan

    2013-01-01

    To investigate the association of five SNPs (rs823083,rs708723,rs4951261,rs823076 and rs16856110) at the PARK16 locus with Parkinson's disease (PD),and to potentiate its forensic application.The genomic DNAs of 215 PD patients and 212 matched controls from the northern Han Chinese population were amplified in two independent PCR systems and subsequently genotyped by digestion with the three endonucleases (Hinf Ⅰ,Nco Ⅰ and Msp Ⅰ).The genetic parameters and association studies were carried out with SPSS 13.0,Haploview version 4.2 and PLINK 1.07 sofiwares.We detected accurately all genotypes in the five SNPs with multiplex PCR-RFLP and mismatched multiplex PCR-RFLP techniques.The genotypes of four SNPs,except for rs823083,were in Hardy-Weinberg equilibrium.The four SNPs,rs16856110,rs4951261,rs708723 and rs823076,which were in linkage equilibrium,should not be associated with PD (P-values ranging from 0.077 to 0.544).The SNPs investigated at the PARK16 locus were not found to be involved in PD-associated blocks in the northern Han Chinese population.The allele distributions of rs708723,rs4951261,rs823076 and rs16856110 in the northern Han Chinese population can be highly polymorphic,which can be applied to genetic analvsis and forensic practices.

  1. Secondary evolution of a self-incompatibility locus in the Brassicaceae genus Leavenworthia.

    Directory of Open Access Journals (Sweden)

    Sier-Ching Chantha

    Full Text Available Self-incompatibility (SI is the flowering plant reproductive system in which self pollen tube growth is inhibited, thereby preventing self-fertilization. SI has evolved independently in several different flowering plant lineages. In all Brassicaceae species in which the molecular basis of SI has been investigated in detail, the product of the S-locus receptor kinase (SRK gene functions as receptor in the initial step of the self pollen-rejection pathway, while that of the S-locus cysteine-rich (SCR gene functions as ligand. Here we examine the hypothesis that the S locus in the Brassicaceae genus Leavenworthia is paralogous with the S locus previously characterized in other members of the family. We also test the hypothesis that self-compatibility in this group is based on disruption of the pollen ligand-producing gene. Sequence analysis of the S-locus genes in Leavenworthia, phylogeny of S alleles, gene expression patterns, and comparative genomics analyses provide support for both hypotheses. Of special interest are two genes located in a non-S locus genomic region of Arabidopsis lyrata that exhibit domain structures, sequences, and phylogenetic histories similar to those of the S-locus genes in Leavenworthia, and that also share synteny with these genes. These A. lyrata genes resemble those comprising the A. lyrata S locus, but they do not function in self-recognition. Moreover, they appear to belong to a lineage that diverged from the ancestral Brassicaceae S-locus genes before allelic diversification at the S locus. We hypothesize that there has been neo-functionalization of these S-locus-like genes in the Leavenworthia lineage, resulting in evolution of a separate ligand-receptor system of SI. Our results also provide support for theoretical models that predict that the least constrained pathway to the evolution of self-compatibility is one involving loss of pollen gene function.

  2. Self Esteem, Locus of Control and Multidimensional Perfectionism as the Predictors of Subjective Well Being

    Science.gov (United States)

    Karatas, Zeynep; Tagay, Ozlem

    2012-01-01

    The purpose of this study is to determine whether there is a relationship between self-esteem, locus of control and multidimensional perfectionism, and the extent to which the variables of self-esteem, locus of control and multidimensional perfectionism contribute to the prediction of subjective well-being. The study was carried out with 318 final…

  3. Fine-Scale Mapping of the FGFR2 Breast Cancer Risk Locus

    DEFF Research Database (Denmark)

    Meyer, Kerstin B; O'Reilly, Martin; Michailidou, Kyriaki

    2013-01-01

    The 10q26 locus in the second intron of FGFR2 is the locus most strongly associated with estrogen-receptor-positive breast cancer in genome-wide association studies. We conducted fine-scale mapping in case-control studies genotyped with a custom chip (iCOGS), comprising 41 studies (n = 89,050) of...

  4. The cps locus of Streptococcus suis serotype 16: Development of a serotype-specific PCR assay

    NARCIS (Netherlands)

    Wang, K.; Weixing, Fan; Wisselink, H.J.; Chengping, Lu

    2011-01-01

    Streptococcus suis serotype 16 can infect pigs and humans. We describe the identification and the characterization of the capsular polysaccharides synthesis locus of S. suis serotype 16. Using PCR primers flanking the capsular polysaccharides synthesis locus, a 30,101-bp fragment was amplified. Twen

  5. Locus of Control, Perceptions and Attributions of Student Teachers in Educational Situations.

    Science.gov (United States)

    Kremer, Lya; Kurtz, Chaya

    Student teachers' perceptions of locus of control was investigated. Locus of control is defined as representing the extent of dependence upon inner or outer forces, the extent one is willing to invest in shaping the environment, and the perception of reinforcement as dependent upon those efforts, or upon random events. The specific questions were:…

  6. The location of the restriction locus for λ·K in Escherichia coli B

    NARCIS (Netherlands)

    Hoekstra, W.P.M.; Haan, P.G. de

    1965-01-01

    Analysis of recombinants from E. coli K 12 Hfr × E. coli B F− crosses showed that one locus on the chromosome of Escherichia coli, controlling restriction and probably also the modification of phage λ, is located between the leading point of the Hfr H chromosome and the locus for threonine synthesis

  7. Mapping of panda plumage color locus on the microsatellite linkage map of the Japanese quail

    Directory of Open Access Journals (Sweden)

    Mizutani Makoto

    2006-01-01

    Full Text Available Abstract Background Panda (s is an autosomal recessive mutation, which displays overall white plumage color with spots of wild-type plumage in the Japanese quail (Coturnix japonica. In a previous study, the s locus was included in the same linkage group as serum albumin (Alb and vitamin-D binding protein (GC which are mapped on chicken (Gallus gallus chromosome 4 (GGA4. In this study, we mapped the s locus on the microsatellite linkage map of the Japanese quail by linkage analysis. Results Segregation data on the s locus were obtained from three-generation families (n = 106. Two microsatellite markers derived from the Japanese quail chromosome 4 (CJA04 and three microsatellite markers derived from GGA4 were genotyped in the three-generation families. We mapped the s locus between GUJ0026 and ABR0544 on CJA04. By comparative mapping with chicken, this locus was mapped between 10.0 Mb and 14.5 Mb region on GGA4. In this region, the endothelin receptor B subtype 2 gene (EDNRB2, an avian-specific paralog of the mammalian endothelin receptor B gene (EDNRB, is located. Because EDNRB is responsible for aganglionic megacolon and spot coat color in mouse, rat and equine, EDNRB2 is suggested to be a candidate gene for the s locus. Conclusion The s locus and the five microsatellite markers were mapped on CJA04 of the Japanese quail. EDNRB2 was suggested to be a candidate gene for the s locus.

  8. Hubungan antara Locus Of Control dan Efektivitas Komunikasi antar Pribadi dengan Problem Focused Coping

    Directory of Open Access Journals (Sweden)

    Eko Sujadi

    2016-03-01

    Full Text Available Problem focused coping need to be possessed by every individual. The purposes of this research were to described locus of control, the effectiveness of interpersonal communication, problem focused coping,the correlation between locus of control with problem focused coping, andthe correlationbetween the effectiveness of interpersonal communication with problem focused coping.This research was descriptive & correlation research by using quantitative approach. Data were collected through a Likert scale questionaire and locus of controlby using inventory Rotters Internal-External Locus of Control (I-E Scale, which was the validity and reliability has been tested. The data were analyzed by percentage technique and product moment correlation. The finding of research are:  1locus of control were in the middle range between internal locus of control and external locus of control with an average as big as 11.46, 2 the general level of effectiveness of interpersonal communication is in high category, 3 the general level of problem focused coping is in high category, 4 there is correlation between locus of control withproblem focused coping, and 5 there is correlation betweeneffectiveness of interpersonal communicationwithproblem focused coping.

  9. Social Self-Efficacy, Academic Locus of Control, and Internet Addiction

    Science.gov (United States)

    Iskender, Murat; Akin, Ahmet

    2010-01-01

    The purpose of this research is to examine the relationship of internet addiction, social self-efficacy, and academic locus of control. Participants were 311 university students who completed a questionnaire package that included the Online Cognition Scale, the Academic Locus of Control Scale, and the Perceived Social Self-efficacy Scale. The…

  10. Developmental regulation of a complete 70kb human β-globin locus in transgenic mice.

    NARCIS (Netherlands)

    J. Strouboulis (John); N.O. Dillon (Niall); F.G. Grosveld (Frank)

    1992-01-01

    textabstractWe have used a linker-based ligation strategy to combine two 35-kb cosmid inserts from the human beta-globin locus into one linear fragment containing the entire locus. This 70-kb fragment was introduced into transgenic mice by microinjection of fertilized eggs. Southern blot analysis sh

  11. Two-step activation of meiosis by the mat1 locus in Schizosaccharomyces pombe

    DEFF Research Database (Denmark)

    Willer, M; Hoffmann, Ulla-Lisbeth; Styrkársdóttir, U

    1995-01-01

    The mat1 locus is a key regulator of both conjugation and meiosis in the fission yeast Schizosaccharomyces pombe. Two alternative DNA segments of this locus, mat1-P and mat1-M, specify the haploid cell types (Plus and Minus). Each segment includes two genes: mat1-P includes mat1-Pc and mat1-Pm, w...

  12. An Examination of Locus of Control, Epistemological Beliefs and Metacognitive Awareness in Preservice Early Childhood Teachers

    Science.gov (United States)

    Bedel, Emine Ferda

    2012-01-01

    This study aims to explore the locus of control, epistemological beliefs and metacognitive awareness levels of preservice early childhood education teachers and to determine the interrelations among these variables. 206 teacher candidates have been asked to fill out Rotter's Internal-External Locus of Control Scale, Central Epistemological Beliefs…

  13. Partial duplication of the PRLR and SPEF2 genes at the late feathering locus in chicken

    NARCIS (Netherlands)

    Elferink, M.G.; Vallee, N.; Jungerius, B.J.; Crooijmans, R.P.M.A.; Groenen, M.A.M.

    2008-01-01

    Background One of the loci responsible for feather development in chickens is K. The K allele is partially dominant to the k+ allele and causes a retard in the emergence of flight feathers at hatch. The K locus is sex linked and located on the Z chromosome. Therefore, the locus can be utilized to pr

  14. Locus of Control as It Relates to the Teaching Style of Elementary Teachers

    Science.gov (United States)

    Ture, Abidemi

    2013-01-01

    This research explored the relationship between elementary teachers' locus of control and teaching style. This research observed elementary teachers in their classrooms coupled with data gathered from information sheets, surveys, and interviews to determine if a relationship exists between the locus of control of the elementary teachers and…

  15. Identification of heat resistant Escherichia coli by qPCR for the locus of heat resistance.

    Science.gov (United States)

    Ma, Angela; Chui, Linda

    2017-02-01

    Three qPCR assays targeting the locus of heat resistance to identify heat resistant clinical Escherichia coli isolates are described. Of 613 isolates, 3 (0.5%) possessed the locus. The assays are a rapid, highly sensitive and specific alternative to screening by heat shock and can be used in food safety surveillance.

  16. The Effect of Supervisor's Locus of Control and Employee Behavior on Supervisor Attributions.

    Science.gov (United States)

    Hillman, Maxine

    Two theoretical areas that lend themselves to study as they relate to supervisor-worker relations are locus of control and attribution theory. This study examined two general problems: (1) how a supervisor behaves toward an employee in relation to how that employee performs in the work place; and (2) how a supervisor's locus of control influences…

  17. Locus of Control as It Relates to the Teaching Style of Elementary Teachers

    Science.gov (United States)

    Ture, Abidemi

    2013-01-01

    This research explored the relationship between elementary teachers' locus of control and teaching style. This research observed elementary teachers in their classrooms coupled with data gathered from information sheets, surveys, and interviews to determine if a relationship exists between the locus of control of the elementary teachers and…

  18. DMPD: The Lps locus: genetic regulation of host responses to bacteriallipopolysaccharide. [Dynamic Macrophage Pathway CSML Database

    Lifescience Database Archive (English)

    Full Text Available 10669111 The Lps locus: genetic regulation of host responses to bacteriallipopolysa...ccharide. Qureshi ST, Gros P, Malo D. Inflamm Res. 1999 Dec;48(12):613-20. (.png) (.svg) (.html) (.csml) Show The... Lps locus: genetic regulation of host responses to bacteriallipopolysaccharide. PubmedID 10669111 Title The

  19. Social Self-Efficacy, Academic Locus of Control, and Internet Addiction

    Science.gov (United States)

    Iskender, Murat; Akin, Ahmet

    2010-01-01

    The purpose of this research is to examine the relationship of internet addiction, social self-efficacy, and academic locus of control. Participants were 311 university students who completed a questionnaire package that included the Online Cognition Scale, the Academic Locus of Control Scale, and the Perceived Social Self-efficacy Scale. The…

  20. Locus ceruleus neurons in people with autism contain no histochemically-detectable mercury.

    Science.gov (United States)

    Pamphlett, Roger; Kum Jew, Stephen

    2016-02-01

    Exposure to environmental mercury has been proposed to play a part in autism. Mercury is selectively taken up by the human locus ceruleus, a region of the brain that has been implicated in autism. We therefore looked for the presence of mercury in the locus ceruleus of people who had autism, using the histochemical technique of autometallography which can detect nanogram amounts of mercury in tissues. In addition, we sought evidence of damage to locus ceruleus neurons in autism by immunostaining for hyperphosphorylated tau. No mercury was found in any neurons of the locus ceruleus of 6 individuals with autism (5 male, 1 female, age range 16-48 years). Mercury was present in locus ceruleus neurons in 7 of 11 (64%) age-matched control individuals who did not have autism, which is significantly more than in individuals with autism. No increase in numbers of locus ceruleus neurons containing hyperphosphorylated tau was detected in people with autism. In conclusion, most people with autism have not been exposed early in life to quantities of mercury large enough to be found later in adult locus ceruleus neurons. Human locus ceruleus neurons are sensitive indicators of mercury exposure, and mercury appears to remain in these neurons indefinitely, so these findings do not support the hypothesis that mercury neurotoxicity plays a role in autism.

  1. Evolution of an Expanded Sex Determining Locus in Volvox

    Science.gov (United States)

    Ferris, Patrick; Olson, Bradley J.S.C.; De Hoff, Peter L.; Douglass, Stephen; Diaz-Cano, David Casero; Prochnik, Simon; Geng, Sa; Rai, Rhitu; Grimwood, Jane; Schmutz, Jeremy; Nishii, Ichiro; Hamaji, Takashi; Nozaki, Hisayoshi; Pellegrini, Matteo; Umen, James G.

    2010-01-01

    Although dimorphic sexes have evolved repeatedly in multicellular eukaryotes, their origins are unknown. The mating locus (MT) of the sexually dimorphic multicellular green alga, Volvox carteri, specifies the production of eggs and sperm and has undergone a remarkable expansion and divergence relative to MT from Chlamydomonas reinhardtii, a closely related unicellular species that has equal-sized gametes. Transcriptome analysis revealed a rewired gametic expression program for Volvox MT genes relative to Chlamydomonas, and identified multiple gender-specific and sex-regulated transcripts. The retinoblastoma tumor suppressor homolog MAT3 is a Volvox MT gene that displays sexually regulated alternative splicing and evidence of gender-specific selection, both indicative of cooption into the sexual cycle. Thus, sex-determining loci impact the evolution of both sex-related and non-sex-related genes. PMID:20395508

  2. Dynamic Quantitative Trait Locus Analysis of Plant Phenomic Data.

    Science.gov (United States)

    Li, Zitong; Sillanpää, Mikko J

    2015-12-01

    Advanced platforms have recently become available for automatic and systematic quantification of plant growth and development. These new techniques can efficiently produce multiple measurements of phenotypes over time, and introduce time as an extra dimension to quantitative trait locus (QTL) studies. Functional mapping utilizes a class of statistical models for identifying QTLs associated with the growth characteristics of interest. A major benefit of functional mapping is that it integrates information over multiple timepoints, and therefore could increase the statistical power for QTL detection. We review the current development of computationally efficient functional mapping methods which provide invaluable tools for analyzing large-scale timecourse data that are readily available in our post-genome era. Copyright © 2015 Elsevier Ltd. All rights reserved.

  3. A comprehensive analysis of the chorion locus in silkmoth.

    Science.gov (United States)

    Chen, Zhiwei; Nohata, Junko; Guo, Huizhen; Li, Shenglong; Liu, Jianqiu; Guo, Youbing; Yamamoto, Kimiko; Kadono-Okuda, Keiko; Liu, Chun; Arunkumar, Kallare P; Nagaraju, Javaregowda; Zhang, Yan; Liu, Shiping; Labropoulou, Vassiliki; Swevers, Luc; Tsitoura, Panagiota; Iatrou, Kostas; Gopinathan, Karumathil P; Goldsmith, Marian R; Xia, Qingyou; Mita, Kazuei

    2015-11-10

    Despite more than 40 years of intense study, essential features of the silkmoth chorion (eggshell) are still not fully understood. To determine the precise structure of the chorion locus, we performed extensive EST analysis, constructed a bacterial artificial chromosome (BAC) contig, and obtained a continuous genomic sequence of 871,711 base pairs. We annotated 127 chorion genes in two segments interrupted by a 164 kb region with 5 non-chorion genes, orthologs of which were on chorion bearing scaffolds in 4 ditrysian families. Detailed transcriptome analysis revealed expression throughout choriogenesis of most chorion genes originally categorized as "middle", and evidence for diverse regulatory mechanisms including cis-elements, alternative splicing and promoter utilization, and antisense RNA. Phylogenetic analysis revealed multigene family associations and faster evolution of early chorion genes and transcriptionally active pseudogenes. Proteomics analysis identified 99 chorion proteins in the eggshell and micropyle localization of 1 early and 6 Hc chorion proteins.

  4. A novel stroke locus identified in a northern Sweden pedigree

    DEFF Research Database (Denmark)

    Janunger, T.; Nilsson-Ardnor, S.; Wiklund, P.-G.

    2009-01-01

    OBJECTIVES: The population of northern Sweden is characterized by reduced genetic diversity and a high incidence of stroke. We sought to reduce genetic variation further, using genealogic analysis in a set of nuclear families affected by stroke, and we subsequently performed a genome-wide scan...... to identify novel stroke susceptibility loci. METHODS: Through genealogy, 7 nuclear families with a common ancestor, connected over 8 generations, were identified. A genome-wide scan using 449 microsatellite markers was performed with subsequent haplotype analyses. RESULTS: A maximum allele-sharing lod score...... of 4.81 on chromosome 9q31-q33 was detected. Haplotype analysis identified a common 2.2-megabase interval in the chromosomal region in 4 of the nuclear families, where an overrepresentation of intracerebral hemorrhage was observed. CONCLUSIONS: We have identified a novel susceptibility locus for stroke...

  5. CSGRqtl: A Comparative Quantitative Trait Locus Database for Saccharinae Grasses.

    Science.gov (United States)

    Zhang, Dong; Paterson, Andrew H

    2017-01-01

    Conventional biparental quantitative trait locus (QTL) mapping has led to some successes in the identification of causal genes in many organisms. QTL likelihood intervals not only provide "prior information" for finer-resolution approaches such as GWAS but also provide better statistical power than GWAS to detect variants with low/rare frequency in a natural population. Here, we describe a new element of an ongoing effort to provide online resources to facilitate study and improvement of the important Saccharinae clade. The primary goal of this new resource is the anchoring of published QTLs for this clade to the Sorghum genome. Genetic map alignments translate a wealth of genomic information from sorghum to Saccharum spp., Miscanthus spp., and other taxa. In addition, genome alignments facilitate comparison of the Saccharinae QTL sets to those of other taxa that enjoy comparable resources, exemplified herein by rice.

  6. [Cajal bodies and histone locus bodies: molecular structure and function].

    Science.gov (United States)

    Khodiuchenko, T A; Krasikova, A V

    2014-01-01

    The review provides modern classification of evolutionarily conserved coilin-containing nuclear bodies of somatic and germ cells that is based on the characteristic features of their molecular composition and the nature of their functions. The main differences between Cajal bodies and histone locus bodies, which are involved in the biogenesis of small nuclear spliceosomal and nucleolar RNAs and in the 3'-end processing of histone precursor messenger RNA, respectively, are considered. It is shown that a significant contribution to the investigation of the diversity of coilin-containing bodies was made by the studies on the architecture of the RNA processing machinery in oocyte nuclei in a number of model organisms. The characteristics features of the molecular composition of coilin-containing bodies in the nuclei of growing oocytes (the so-called germinal vesicles) of vertebrates, including amphibians and birds, are described.

  7. Cajal bodies and histone locus bodies in Drosophila and Xenopus.

    Science.gov (United States)

    Nizami, Z F; Deryusheva, S; Gall, J G

    2010-01-01

    The organization of the cell nucleus into specialized compartments is important for nuclear function. We address the significance of compartmentalization by studying the Cajal body, an evolutionarily conserved nuclear organelle proposed to be involved in such diverse functions as assembly of the spliceosome, assembly of the transcription machinery, and modification of spliceosomal small nuclear RNAs. The Cajal body is typically identified by the presence of coilin, a protein of poorly defined function. Here, we demonstrate that coilin is not a unique Cajal body marker but also occurs in a related yet distinct nuclear organelle known as the histone locus body in both Drosophila and Xenopus. We stress the importance of multiple markers not only for identification of nuclear bodies but also for assessing their functional significance.

  8. Natural history of the ERVWE1 endogenous retroviral locus

    Directory of Open Access Journals (Sweden)

    Duret Laurent

    2005-09-01

    Full Text Available Abstract Background The human HERV-W multicopy family includes a unique proviral locus, termed ERVWE1, whose full-length envelope ORF was preserved through evolution by the action of a selective pressure. The encoded Env protein (Syncytin is involved in hominoid placental physiology. Results In order to infer the natural history of this domestication process, a comparative genomic analysis of the human 7q21.2 syntenic regions in eutherians was performed. In primates, this region was progressively colonized by LTR-elements, leading to two different evolutionary pathways in Cercopithecidae and Hominidae, a genetic drift versus a domestication, respectively. Conclusion The preservation in Hominoids of a genomic structure consisting in the juxtaposition of a retrotransposon-derived MaLR LTR and the ERVWE1 provirus suggests a functional link between both elements.

  9. Natural history of the ERVWE1 endogenous retroviral locus

    Science.gov (United States)

    Bonnaud, Bertrand; Beliaeff, Jean; Bouton, Olivier; Oriol, Guy; Duret, Laurent; Mallet, François

    2005-01-01

    Background The human HERV-W multicopy family includes a unique proviral locus, termed ERVWE1, whose full-length envelope ORF was preserved through evolution by the action of a selective pressure. The encoded Env protein (Syncytin) is involved in hominoid placental physiology. Results In order to infer the natural history of this domestication process, a comparative genomic analysis of the human 7q21.2 syntenic regions in eutherians was performed. In primates, this region was progressively colonized by LTR-elements, leading to two different evolutionary pathways in Cercopithecidae and Hominidae, a genetic drift versus a domestication, respectively. Conclusion The preservation in Hominoids of a genomic structure consisting in the juxtaposition of a retrotransposon-derived MaLR LTR and the ERVWE1 provirus suggests a functional link between both elements. PMID:16176588

  10. Role of CTCF protein in regulating FMR1 locus transcription.

    Directory of Open Access Journals (Sweden)

    Stella Lanni

    Full Text Available Fragile X syndrome (FXS, the leading cause of inherited intellectual disability, is caused by epigenetic silencing of the FMR1 gene, through expansion and methylation of a CGG triplet repeat (methylated full mutation. An antisense transcript (FMR1-AS1, starting from both promoter and intron 2 of the FMR1 gene, was demonstrated in transcriptionally active alleles, but not in silent FXS alleles. Moreover, a DNA methylation boundary, which is lost in FXS, was recently identified upstream of the FMR1 gene. Several nuclear proteins bind to this region, like the insulator protein CTCF. Here we demonstrate for the first time that rare unmethylated full mutation (UFM alleles present the same boundary described in wild type (WT alleles and that CTCF binds to this region, as well as to the FMR1 gene promoter, exon 1 and intron 2 binding sites. Contrariwise, DNA methylation prevents CTCF binding to FXS alleles. Drug-induced CpGs demethylation does not restore this binding. CTCF knock-down experiments clearly established that CTCF does not act as insulator at the active FMR1 locus, despite the presence of a CGG expansion. CTCF depletion induces heterochromatinic histone configuration of the FMR1 locus and results in reduction of FMR1 transcription, which however is not accompanied by spreading of DNA methylation towards the FMR1 promoter. CTCF depletion is also associated with FMR1-AS1 mRNA reduction. Antisense RNA, like sense transcript, is upregulated in UFM and absent in FXS cells and its splicing is correlated to that of the FMR1-mRNA. We conclude that CTCF has a complex role in regulating FMR1 expression, probably through the organization of chromatin loops between sense/antisense transcriptional regulatory regions, as suggested by bioinformatics analysis.

  11. Identification of a siderophore utilization locus in nontypeable Haemophilus influenzae

    Directory of Open Access Journals (Sweden)

    Seale Thomas W

    2010-04-01

    Full Text Available Abstract Background Haemophilus influenzae has an absolute aerobic growth requirement for either heme, or iron in the presence of protoporphyrin IX. Both iron and heme in the mammalian host are strictly limited in their availability to invading microorganisms. Many bacterial species overcome iron limitation in their environment by the synthesis and secretion of small iron binding molecules termed siderophores, which bind iron and deliver it into the bacterial cell via specific siderophore receptor proteins on the bacterial cell surface. There are currently no reports of siderophore production or utilization by H. influenzae. Results Comparative genomics revealed a putative four gene operon in the recently sequenced nontypeable H. influenzae strain R2846 that encodes predicted proteins exhibiting significant identity at the amino acid level to proteins involved in the utilization of the siderophore ferrichrome in other bacterial species. No siderophore biosynthesis genes were identified in the R2846 genome. Both comparative genomics and a PCR based analysis identified several additional H. influenzae strains possessing this operon. In growth curve assays strains containing the genes were able to utilize ferrichrome as an iron source. H. influenzae strains lacking the operon were unable to obtain iron from ferrichrome. An insertional mutation in one gene of the operon abrogated the ability of strains to utilize ferrichrome. In addition transcription of genes in the identified operon were repressible by high iron/heme levels in the growth media. Conclusions We have identified an iron/heme-repressible siderophore utilization locus present in several nontypeable H. influenzae strains. The same strains do not possess genes encoding proteins associated with siderophore synthesis. The siderophore utilization locus may enable the utilization of siderophores produced by other microorganisms in the polymicrobial environmental niche of the human nasopharynx

  12. The locus of semantic interference in picture naming

    Directory of Open Access Journals (Sweden)

    Pedro Macizo

    2003-01-01

    Full Text Available El locus del efecto de interferencia semántica en la denominación de dibujos. En los experimentos que se presentan se utilizó el procedimiento de priming enmascarado para explorar el locus del efecto de interferencia semántica. Para ello se manipuló la naturaleza de la tarea (denominación y decisión de género, el tipo de relación entre el prime y el target (semántica y fonológica y el tiempo de presentación del prime. Los resultados indicaron que el efecto de interferencia semántica aparece en las tareas de denominación (Experimento 1 y de decisión de género (Experimento 2, con tiempos de presentación del prime de 100 ms. Este resultado replica el efecto encontrado por otros investigadores y lo extiende a la tarea de decisión de género. Por otro lado, el efecto de facilitación fonológica no apareció en la tarea de decisión de género (Experimento 3. Este patrón de resultados sugiere que el efecto de interferencia semántica es consecuencia de procesos que ocurren en el nivel de representación del lemma, y que la tarea de decisión de género no está influenciada por la activación fonológica.

  13. African Americans with cancer: the relationships among self-esteem, locus of control, and health perception.

    Science.gov (United States)

    Swinney, Jean E

    2002-10-01

    The purpose of this study was to describe and examine the relationships among self-esteem, locus of control, and perceived health status in African Americans with cancer and to identify predictors of perceived health status. A convenience sample of 95 oncology outpatients at two large medical facilities completed the Tennessee Self-Concept Scale, the Multidimensional Health Locus of Control Scale, and the Cantril Ladder, a measurement of perceived health. In an audiotaped interview two open-ended questions were used to clarify participants' Cantril Ladder scores. A significant positive relationship was discovered between self-esteem and powerful others health locus of control (p Self-esteem and an internal health locus of control were found to account for 23% of the perceived variance in health status. In addition, interview data indicated that participants with normal to high levels of self-esteem and an internal health locus of control perceived their state of health and well-being positively.

  14. Aggression and Multidimensional Perfectionism as the Predictors of Locus of Control

    Directory of Open Access Journals (Sweden)

    Zeynep KARATAŞ

    2012-12-01

    Full Text Available The purpose of this study was to determine whether there is a relationship between locus of control, aggression and multidimensional perfectionism, and the extent to which the variables of aggression and multidimensional perfectionism contribute to the prediction of locus of control. The study was carried out with students of 268 teachers colleges in Mehmet Akif Ersoy University. Aggression Questionnaire adopted by Can (2002, Locus of Control Scale (Dağ, 2002 and Multi-Dimensional Perfectionism Scale adopted by Oral (1999 were used in the study. Correlation Coefficient of Pearson Moments Multiplying and Gradual Regression Analysis were used in the analysis of the data. As a consequence, it was determined that there is a positive relationship between locus of control, aggression and multi-dimensional perfectionism. Also, it was observed that the variables of aggression and multidimensional perfectionism significantly predict locus of control.

  15. Evidence for the existence of a fourth dominantly inherited spinocerebellar ataxia locus

    Energy Technology Data Exchange (ETDEWEB)

    Lopes-Cendes, I. (Montreal General Hospital Research Institute, Quebec (Canada) Montreal Neurological Institute and Hospital, Quebec (Canada) McGill Univ., Quebec (Canada)); Andermann, E. (Montreal Neurological Institute and Hospital, Quebec (Canada) McGill Univ., Quebec (Canada)); Rouleau, G.A. (Montreal General Hospital Research Institute, Quebec (Canada) Montreal Neurological Institute and Hospital, Quebec (Canada))

    1994-05-01

    The autosomal dominantly inherited spinocerebellar ataxias (SCAs) are a heterogeneous group of disorders. To date, three loci have been identified: The SCA1 locus (on chr 6p), the SCA2 locus (on chr 12q), and more recently a Machado-Joseph disease (MJD) locus (on chr 14q). The authors have studied one large French-Canadian kindred with four generations of living affected individuals segregating an autosomal dominant form of SCA. Linkage analysis using anonymous DNA markers that flank the three previously described loci significantly exclude the French-Canadian kindred from the SCA1, SCA2, and MJD loci. Therefore, a fourth, still unmapped SCA locus remains to be identified. In addition, the unique clinical phenotype present in all affected individuals of the French-Canadian kindred might be characteristic of this still unmapped SCA locus. 34 refs., 2 figs., 2 tabs.

  16. A 27-locus STR assay to meet all United States and European law enforcement agency standards.

    Science.gov (United States)

    Schumm, James W; Gutierrez-Mateo, Cristina; Tan, Eugene; Selden, Richard

    2013-11-01

    Different national and international agencies have selected specific STR sets for forensic database use. To enhance database comparison across national and international borders, a 27-locus multiplex system was developed comprising all 15 STR loci of the European standard set, the current 13 STR loci of the CODIS core, the proposed 22 STR loci of the expanded CODIS core, 4 additional commonly used STR loci, and the amelogenin locus. Development required iterative primer design to resolve primer-related artifacts, amplicon sizing, and locus-to-locus balance issues. The 19.5-min assay incorporated newly developed six-dye chemistry analyzed using a novel microfluidic electrophoresis instrument capable of simultaneous detection and discrimination of 8 or more fluorescent dyes. The 27-locus multiplex offers the potential for a new international STR standard permitting laboratories in any jurisdiction to use a single reaction to determine profiles for loci they typically generate plus an expanded common STR profiling set of global interest.

  17. Is the novel SCKL3 at 14q23 the predominant Seckel locus?

    Science.gov (United States)

    Kilinç, Mehmet Okyay; Ninis, Vasiliki Ninidu; Ugur, Sibel Aylin; Tüysüz, Beyhan; Seven, Mehmet; Balci, Sevim; Goodship, Judith; Tolun, Aslihan

    2003-11-01

    Seckel syndrome (SCKL) is a rare disease with wide phenotypic heterogeneity. A locus (SCKL1) has been identified at 3q and another (SCKL2) at 18p, both in single kindreds afflicted with the syndrome. We report here a novel locus (SCKL3) at 14q by linkage analysis in 13 Turkish families. In total, 18 affected and 10 unaffected sibs were included in the study. Of the 10 informative families, nine with parental consanguinity and one reportedly nonconsanguineous but with two affected sibs, five were indicative of linkage to the novel locus. One of those families also linked to the SCKL1 locus. A consanguineous family with one affected sib was indicative of linkage to SCKL2. The novel gene locus SCKL3 is 1.18 cM and harbors ménage a trois 1, a gene with a role in DNA repair.

  18. Structure and expression of the S locus-related genes of maize.

    Science.gov (United States)

    Zhang, R; Walker, J C

    1993-03-01

    The extracellular of the putative receptor-like protein kinase, ZmPK1, is related to the self-incompatibility locus (S-locus) genes of Brassica. We have isolated and characterized a genomic DNA clone of ZmPK1 and three additional genes from maize that are highly related to ZmPK1. These three S-locus related genes do not appear to have the protein kinase catalytic domain that is found in ZmPK1. One or more of these genes are expressed specifically in the silks. This initial description of S-locus related genes in monocotyledonous plants suggests that the S-locus domain may be involved in several different cellular functions in a wide variety of plants.

  19. Organization of the cpe locus in CPE-positive clostridium perfringens type C and D isolates.

    Directory of Open Access Journals (Sweden)

    Jihong Li

    Full Text Available Clostridium perfringens enterotoxin (encoded by the cpe gene contributes to several important human, and possibly veterinary, enteric diseases. The current study investigated whether cpe locus organization in type C or D isolates resembles one of the three (one chromosomal and two plasmid-borne cpe loci commonly found amongst type A isolates. Multiplex PCR assays capable of detecting sequences in those type A cpe loci failed to amplify products from cpe-positive type C and D isolates, indicating these isolates possess different cpe locus arrangements. Therefore, restriction fragments containing the cpe gene were cloned and sequenced from two type C isolates and one type D isolate. The obtained cpe locus sequences were then used to construct an overlapping PCR assay to assess cpe locus diversity amongst other cpe-positive type C and D isolates. All seven surveyed cpe-positive type C isolates had a plasmid-borne cpe locus partially resembling the cpe locus of type A isolates carrying a chromosomal cpe gene. In contrast, all eight type D isolates shared the same plasmid-borne cpe locus, which differed substantially from the cpe locus present in other C. perfringens by containing two copies of an ORF with 67% identity to a transposase gene (COG4644 found in Tn1546, but not previously associated with the cpe gene. These results identify greater diversity amongst cpe locus organization than previously appreciated, providing new insights into cpe locus evolution. Finally, evidence for cpe gene mobilization was found for both type C and D isolates, which could explain their cpe plasmid diversity.

  20. Organization of the cpe Locus in CPE-Positive Clostridium perfringens Type C and D Isolates

    Science.gov (United States)

    Li, Jihong; Miyamoto, Kazuaki; Sayeed, Sameera; McClane, Bruce A.

    2010-01-01

    Clostridium perfringens enterotoxin (encoded by the cpe gene) contributes to several important human, and possibly veterinary, enteric diseases. The current study investigated whether cpe locus organization in type C or D isolates resembles one of the three (one chromosomal and two plasmid-borne) cpe loci commonly found amongst type A isolates. Multiplex PCR assays capable of detecting sequences in those type A cpe loci failed to amplify products from cpe-positive type C and D isolates, indicating these isolates possess different cpe locus arrangements. Therefore, restriction fragments containing the cpe gene were cloned and sequenced from two type C isolates and one type D isolate. The obtained cpe locus sequences were then used to construct an overlapping PCR assay to assess cpe locus diversity amongst other cpe-positive type C and D isolates. All seven surveyed cpe-positive type C isolates had a plasmid-borne cpe locus partially resembling the cpe locus of type A isolates carrying a chromosomal cpe gene. In contrast, all eight type D isolates shared the same plasmid-borne cpe locus, which differed substantially from the cpe locus present in other C. perfringens by containing two copies of an ORF with 67% identity to a transposase gene (COG4644) found in Tn1546, but not previously associated with the cpe gene. These results identify greater diversity amongst cpe locus organization than previously appreciated, providing new insights into cpe locus evolution. Finally, evidence for cpe gene mobilization was found for both type C and D isolates, which could explain their cpe plasmid diversity. PMID:20532170

  1. Buffering Role of Locus of Control on Stress among the College/University Teachers of Bahawalpur

    Directory of Open Access Journals (Sweden)

    Aqeel Ahmad Khan (Corresponding author

    2012-06-01

    Full Text Available The present research is aimed to ascertain the role of locus of control in mediating or coping on various degree/levels of stress among the college/university teachers of Bahawalpur. For that purpose a sample of N=200 male/female college/university teacherswas selected by convenient sampling. Research tools, Locus of control by Julian Rotter (1966 and Stress questionnaire by International Stress Management Association UK, (2009 were administered for data collection. After the collection of data it was analyzedby SPSS. The results shows that the teachers identified with internal locus of control reveal low level of stress as contrast to the teachers with external locus of control. The study also confirms that high internal locus of control determines high coping andmediating ability of stress among the teachers. The study also pointed out that the teachers with external locus of control were more incline or prone to stress. Furthermore, Pearson and Spearman’s Correlation results at significant level of .000 show that bothvariables are highly correlated. Similarly, overall Mean of locus of control and Coefficient of variation reveals the high consistency role in relation with stress.

  2. Internal health locus of control predicts willingness to track health behaviors online and with smartphone applications.

    Science.gov (United States)

    Bennett, Brooke L; Goldstein, Carly M; Gathright, Emily C; Hughes, Joel W; Latner, Janet D

    2017-04-17

    Given rising technology use across all demographic groups, digital interventions offer a potential strategy for increasing access to health information and care. Research is lacking on identifying individual differences that impact willingness to use digital interventions, which may affect patient engagement. Health locus of control, the amount of control an individual believes they have over their own health, may predict willingness to use mobile health (mHealth) applications ('apps') and online trackers. A cross-sectional study (n = 276) was conducted to assess college students' health locus of control beliefs and willingness to use health apps and online trackers. Internal and powerful other health locus of control beliefs predicted willingness to use health apps and online trackers while chance health locus of control beliefs did not. Individuals with internal and powerful other health locus of control beliefs are more willing than those with chance health locus of control beliefs to utilize a form of technology to monitor or change health behaviors. Health locus of control is an easy-to-assess patient characteristic providers can measure to identify which patients are more likely to utilize mHealth apps and online trackers.

  3. The X-linked F cell production locus: Genetic mapping and role in fetal hemoglobin production

    Energy Technology Data Exchange (ETDEWEB)

    Chang, Y.C.; Smith, K.D.; Moore, R.D. [John Hopkins Univ., Baltimore, MD (United States)] [and others

    1994-09-01

    Postnatal fetal hemoglobin (Hb F) production is confined to a subset of erythocytes termed F-cells. There is a 10-20 fold variation in F-cell production in sickle cell disease (SCD) and normal individuals. Most of the variation in F-cell production has been attributed to a diallelic (High, Low) X-linked gene, the F-cell production (FCP) locus that we recently mapped to Xp22.2-22.3 (LOD=4.56, theta=0.04). Using multiple regression analysis in 262 Jamaican SCD patients we determined the relative contribution of the FCP locus and other variables previously associated with variation in Hb F level (gender, age, beta-globin haplotypes, number of alpha-globin genes and the FCP locus phenotypes). When the FCP locus is in the regression model, the FCP locus alone accounts for approximately 40% of the variation in Hb F level while the contribution of age, alpha-globin gene number, and beta-globin haplotypes was insignificant. When individuals with High FCP allele are removed from the analysis, the beta globin haplotype now contribute to >10% of the Hb F variation. We conclude that the X-linked FCP locus is the major determinant of all known variables in Hb F production. Using 4 highly polymorphic dinucleotide repeat markers that we identified from cosmids in Xp22.2-22.3, have localized the FCP locus to a 1 Mb minimal candidate region between DXS143 and DXS410.

  4. Confirmation of the SCA-2 locus as an alternative locus for dominantly inherited spinocerebellar ataxias and refinement of the candidate region

    Energy Technology Data Exchange (ETDEWEB)

    Lopes-Cendes, I.; Rouleau, G.A. (Montreal General Hospital Research Institute, Quebec (Canada)); Andermann, E.; Andermann, F. (Montreal Neurological Institute and Hospital (Canada)); Attig, E. (Hotel Dieu de Montreal (Canada)); Bosch, S.; Wagner, M. (Univ. Hospital, Innsbruck (Austria))

    1994-05-01

    The autosomal dominant spinocerebellar ataxias (SCAs) are a clinically heterogeneous group of neurodegenerative diseases. To date, two SCA loci have been identified - one locus (SCA-1) on the short arm of chromosome 6 and the second locus (SCA-2) on the long arm of chromosome 12. The authors have studied two large kindreds from different ethnic backgrounds, segregating an autosomal dominant form of SCA. A total of 207 living individuals, including 50 affected, were examined, and blood was collected. Linkage analysis was performed using anonymous DNA markers which flank the two previously described loci. The results demonstrate that the two kindreds, one Austrian-Canadian and one French-Canadian, are linked to SCA-2 (chromosome 12q). Multipoint linkage analysis places the SCA-2 locus within a region of approximately 16 cM between the microsatellites D12S58 and D12S84/D12S105 (odds ratio 2,371:1 in favor of this position). The authors show that the SCA-2 locus is not a private gene and represents an alternative SCA locus. 51 refs., 2 figs., 2 tabs.

  5. Personal networks and locus of control in large urban centers of Argentina

    Directory of Open Access Journals (Sweden)

    Pablo De Grande

    2013-12-01

    Full Text Available This study analyzes the relationship between locus of control and interpersonal relations structures in Argentina. After a representative sample (n = 1500 of households in seven major urban centers (>200,000 inhabitants, it examines the relationship between the externality of locus of control and different aspects of personal networks of each respondent. The results show that people having more relations experiment lower levels of externality of locus of control. Likewise, lower levels of externality are informed when personal ties outside the neighborhood are available, as well as ties high educational level. In this regard, significant associations are verified between control and personal relations structures.

  6. The immunoglobulin light chain locus of the turkey, Meleagris gallopavo.

    Science.gov (United States)

    Bao, Yonghua; Wu, Sun; Zang, Yunlong; Wang, Hui; Song, Xiangfeng; Xu, Chunyang; Xie, Bohong; Guo, Yongchen

    2012-06-15

    To date, most jawed vertebrate species encode more than one immunoglobulin light (IgL) chain isotypes. It has been shown that several bird species (chickens, white Pekin or domestic duck, and zebra finches) exclusively express lambda isotype. We analyze here the genomic organization of another bird species turkey IgL genes based on the recently released genome data. The turkey IgL locus located on chromosome 17 spans approximately 75.2kb and contains a single functional V(λ) gene, twenty V(λ) pseudogenes, and a single functional J(λ)-C(λ) block. These data suggest that the genomic organization of bird IgL chain genes seems to be conserved. Ten cDNA clones from turkey Igλ chain containing almost full-length V(λ), J(λ) and C(λ) segments were acquired. The comparison of V(λ) cDNA sequences to all the germline V(λ) segments suggests that turkey species may be generating IgL chain diversity by gene conversion and somatic hypermutation like the chicken. This study provides insights into the immunoglobulin light chain genes in another bird species.

  7. Genetic mapping of the dentinogenesis imperfecta type II locus

    Energy Technology Data Exchange (ETDEWEB)

    Crosby, A.H.; Dixon, M.J. [Univ. of Manchester (United Kingdom); Scherpbier-Heddema, T. [Fox Chase Cancer Center, Philadelphia, PA (United States)] [and others

    1995-10-01

    Dentinogenesis imperfecta type II (DGI-II) is an autosomal dominant disorder of dentin formation, which has previously been mapped to chromosome 4q12-21. In the current study, six novel short tandem-repeat polymorphisms (STRPs) have been isolated, five of which show significant evidence of linkage to DGI-II. To determine the order of the STRPs and define the genetic distance between them, nine loci (including polymorphisms for two known genes) were mapped through the CEPH reference pedigrees. The resulting genetic map encompasses 16.3 cM on the sex-averaged map. To combine this map with a physical map of the region, all of the STRPs were mapped through a somatic cell hybrid panel. The most likely location for the DGI-II locus within the fixed marker map is in the D4S2691-D4S2692 interval of 6.6 cM. The presence of a marker that shows no recombination with the DGI-II phenotype between the flanking markers provides an important anchor point for the creation of physical continuity across the DGI-II candidate region. 38 refs., 4 figs., 2 tabs.

  8. Hearing the zero locus of a magnetic field

    Energy Technology Data Exchange (ETDEWEB)

    Montgomery, R. [California Univ., Santa Cruz, CA (United States). Dept. of Mathematics

    1995-04-01

    We investigate the ground state of a two-dimensional quantum particle in a magnetic field where the field vanishes nondegenerately along a closed curve. We show that the ground state concentrates on this curve as e/h tends to infinity, where e is the charge, and that the ground state energy grows like (e/h){sup 2/3}. These statements are true for any energy level, the level being fixed as the charge tends to infinity. If the magnitude of the gradient of the magnetic field is a constant b{sub 0} along its zero locus, then we get the precise asymptotics (e/h){sup 2/3}(b{sub 0}){sup 2/3} E{sub *} + O(1) for every energy level. The constant E{sub *} {approx_equal} .5698 is the infimum of the ground state energies E({beta}) of the anharmonic oscillator family -d{sup 2}/dy{sup 2} + (1/2 y{sup 2} - {beta}){sup 2}. (orig.)

  9. A locus regulating bronchial hyperresponsiveness maps to chromosome 5q

    Energy Technology Data Exchange (ETDEWEB)

    Levitt, R.C.; Meyers, D.A. [Johns Hopkins Medical Institutions, Baltimore, MD (United States); Bleecker, E.R. [Univ. of Maryland, Baltimore, MD (United States)] [and others

    1994-09-01

    Bronchial hyperresponsiveness (BHR) is one of the hallmarks of asthma. BHR correlates well with asthmatic symptoms and the response to treatment. Moreover, BHR appears to be closely related to airways inflammation. Numerous studies have demonstrated a familial aggregation; however, this phenotype is not likely inherited as a simple Mendelian trait. BHR is also closely associated with total serum IgE levels, as are allergy and asthma. We studied 92 families from Northern Holland ascertained through a parent with asthma who were originally studied between 1962-1970. Since there are a number of candidate genes on chromosome 5q potentially important in producing BHR, families were genotyped for markers in this region. These genes regulate IgE production and the cellular elements that are likely involved in inflammation associated with BHR, allergy and asthma. They include IL-4, IL-3, IL-5, IL-9, IL-12, IL-13 and GM-CSF. Linkage of BHR with markers on 5q was tested using a model free sib-pair method. The data suggest a locus for BHR maps near the cytokine gene cluster on 5q. This region appears critical in producing susceptibility to BHR and possibly to asthma.

  10. Pupil diameter covaries with BOLD activity in human locus coeruleus.

    Science.gov (United States)

    Murphy, Peter R; O'Connell, Redmond G; O'Sullivan, Michael; Robertson, Ian H; Balsters, Joshua H

    2014-08-01

    The locus coeruleus-noradrenergic (LC-NA) neuromodulatory system has been implicated in a broad array of cognitive processes, yet scope for investigating this system's function in humans is currently limited by an absence of reliable non-invasive measures of LC activity. Although pupil diameter has been employed as a proxy measure of LC activity in numerous studies, empirical evidence for a relationship between the two is lacking. In the present study, we sought to rigorously probe the relationship between pupil diameter and BOLD activity localized to the human LC. Simultaneous pupillometry and fMRI revealed a relationship between continuous pupil diameter and BOLD activity in a dorsal pontine cluster overlapping with the LC, as localized via neuromelanin-sensitive structural imaging and an LC atlas. This relationship was present both at rest and during performance of a two-stimulus oddball task, with and without spatial smoothing of the fMRI data, and survived retrospective image correction for physiological noise. Furthermore, the spatial extent of this pupil/LC relationship guided a volume-of-interest analysis in which we provide the first demonstration in humans of a fundamental characteristic of animal LC activity: phasic modulation by oddball stimulus relevance. Taken together, these findings highlight the potential for utilizing pupil diameter to achieve a more comprehensive understanding of the role of the LC-NA system in human cognition.

  11. Locus coeruleus and dopaminergic consolidation of everyday memory

    Science.gov (United States)

    Takeuchi, Tomonori; Duszkiewicz, Adrian J.; Sonneborn, Alex; Spooner, Patrick A.; Yamasaki, Miwako; Watanabe, Masahiko; Smith, Caroline C.; Fernández, Guillén; Deisseroth, Karl; Greene, Robert W.; Morris, Richard G. M.

    2016-01-01

    Summary The retention of episodic-like memory is enhanced, in humans and animals, when something novel happens shortly before or after encoding. Using an everyday memory task in mice, we sought the neurons mediating this dopamine-dependent novelty effect, previously thought to originate exclusively from the tyrosine hydroxylase-expressing (TH+) neurons in the ventral tegmental area (VTA). We report that neuronal firing in the locus coeruleus (LC) is especially sensitive to environmental novelty, LC-TH+ neurons project more profusely than VTA-TH+ neurons to the hippocampus, optogenetic activation of LC-TH+ neurons mimics the novelty effect, and this novelty-associated memory enhancement is unaffected by VTA inactivation. Surprisingly, two effects of LC-TH+ photoactivation are sensitive to hippocampal D1/D5 receptor blockade and resistant to adrenoceptors blockade – memory enhancement and long lasting potentiation of synaptic transmission in CA1 ex vivo. Thus, LC-TH+ neurons can mediate post-encoding memory enhancement in a manner consistent with possible co-release of dopamine in hippocampus. PMID:27602521

  12. Rapid multi-locus sequence typing using microfluidic biochips.

    Directory of Open Access Journals (Sweden)

    Timothy D Read

    Full Text Available BACKGROUND: Multiple locus sequence typing (MLST has become a central genotyping strategy for analysis of bacterial populations. The scheme involves de novo sequencing of 6-8 housekeeping loci to assign unique sequence types. In this work we adapted MLST to a rapid microfluidics platform in order to enhance speed and reduce laboratory labor time. METHODOLOGY/PRINCIPAL FINDINGS: Using two integrated microfluidic devices, DNA was purified from 100 Bacillus cereus soil isolates, used as a template for multiplex amplification of 7 loci and sequenced on forward and reverse strands. The time on instrument from loading genomic DNA to generation of electropherograms was only 1.5 hours. We obtained full-length sequence of all seven MLST alleles from 84 representing 46 different Sequence Types. At least one allele could be sequenced from a further 15 strains. The nucleotide diversity of B. cereus isolated in this study from one location in Rockville, Maryland (0.04 substitutions per site was found to be as great as the global collection of isolates. CONCLUSIONS/SIGNIFICANCE: Biogeographical investigation of pathogens is only one of a panoply of possible applications of microfluidics based MLST; others include microbiologic forensics, biothreat identification, and rapid characterization of human clinical samples.

  13. Combined expression trait correlations and expression quantitative trait locus mapping.

    Directory of Open Access Journals (Sweden)

    Hong Lan

    2006-01-01

    Full Text Available Coordinated regulation of gene expression levels across a series of experimental conditions provides valuable information about the functions of correlated transcripts. The consideration of gene expression correlation over a time or tissue dimension has proved valuable in predicting gene function. Here, we consider correlations over a genetic dimension. In addition to identifying coregulated genes, the genetic dimension also supplies us with information about the genomic locations of putative regulatory loci. We calculated correlations among approximately 45,000 expression traits derived from 60 individuals in an F2 sample segregating for obesity and diabetes. By combining the correlation results with linkage mapping information, we were able to identify regulatory networks, make functional predictions for uncharacterized genes, and characterize novel members of known pathways. We found evidence of coordinate regulation of 174 G protein-coupled receptor protein signaling pathway expression traits. Of the 174 traits, 50 had their major LOD peak within 10 cM of a locus on Chromosome 2, and 81 others had a secondary peak in this region. We also characterized a Riken cDNA clone that showed strong correlation with stearoyl-CoA desaturase 1 expression. Experimental validation confirmed that this clone is involved in the regulation of lipid metabolism. We conclude that trait correlation combined with linkage mapping can reveal regulatory networks that would otherwise be missed if we studied only mRNA traits with statistically significant linkages in this small cross. The combined analysis is more sensitive compared with linkage mapping alone.

  14. Polarized gene conversion at the bz locus of maize.

    Science.gov (United States)

    Dooner, Hugo K; He, Limei

    2014-09-23

    Nucleotide diversity is greater in maize than in most organisms studied to date, so allelic pairs in a hybrid tend to be highly polymorphic. Most recombination events between such pairs of maize polymorphic alleles are crossovers. However, intragenic recombination events not associated with flanking marker exchange, corresponding to noncrossover gene conversions, predominate between alleles derived from the same progenitor. In these dimorphic heterozygotes, the two alleles differ only at the two mutant sites between which recombination is being measured. To investigate whether gene conversion at the bz locus is polarized, two large diallel crossing matrices involving mutant sites spread across the bz gene were performed and more than 2,500 intragenic recombinants were scored. In both diallels, around 90% of recombinants could be accounted for by gene conversion. Furthermore, conversion exhibited a striking polarity, with sites located within 150 bp of the start and stop codons converting more frequently than sites located in the middle of the gene. The implications of these findings are discussed with reference to recent data from genome-wide studies in other plants.

  15. Adenylate kinase locus 1 polymorphism and feto-placental development.

    Science.gov (United States)

    Fulvia, Gloria-Bottini; Antonio, Pietroiusti; Anna, Neri; Patrizia, Saccucci; Ada, Amante; Egidio, Bottini; Andrea, Magrini

    2011-12-01

    Recently our group has found that the correlation between birth weight and placental weight - an index of a balanced feto-placental unit development - is influenced by genetic factors. Since adenylate kinase locus 1 (AK₁) is a polymorphic enzyme that plays an important role in the synthesis of nucleotides required for many metabolic functions, we have investigated the possible role of its genetic variability in the correlation between birth weight and placental weight. 342 consecutive healthy newborn infants from the population of Rome (Italy) and 286 puerperae from another population from Central Italy were studied. The correlation coefficient between birth weight and placental weight is much higher in infants with low activity AK₁2-1 phenotype than in those with high activity AK₁1 phenotype. The difference between AK₁ and AK₁2-1 is well marked only in newborns with a gestational age greater than 38 weeks and it is not influenced by sex, maternal age and maternal smoking. A similar pattern is observed with maternal AK₁ phenotype. These results suggest that the difference in enzymatic activity between AK₁ phenotypes influencing the equilibrium among ATP, ADP, AMP and adenosine could have an important role in a balanced development of feto-placental unit. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

  16. Locus Adh of Drosophila melanogaster under selection for delayed senescence

    Energy Technology Data Exchange (ETDEWEB)

    Khaustova, N.D. [Odessa State Univ. (Ukraine)

    1995-05-01

    Dynamics of the Adh activity and frequencies of alleles Adh{sup F} and Adh{sup S} were analyzed under selection for delayed senescence. The experiments were performed on Drosophila melanogaster. Lines Adh{sup S}cn and Adh{sup F}vg and experimental populations cn` and vg`, selected for an increased duration of reproductive period (late oviposition) were used. Analysis of fertility, longevity, viability and resistance to starvation showed that selection for late oviposition resulted in delayed senescence of flies of the experimental populations. Genetic structure of population vg` changed considerably with regard to the Adh locus. This was confirmed by parameters of activity, thermostability, and electrophoretic mobility of the enzyme isolated from flies after 30 generations of selection. Analysis of frequencies of the Adh alleles showed that in both selected populations, which initially had different genetic composition, accumulated allele Adh{sup S}, which encodes the isozyme that is less active but more resistant to inactivation. Genetic mechanism of delayed senescence in Drosophila is assumed to involve selection at vitally important enzyme loci, including Adh. 18 refs., 2 tabs., 4 figs.

  17. The achromatic locus: effect of navigation direction in color space.

    Science.gov (United States)

    Chauhan, Tushar; Perales, Esther; Xiao, Kaida; Hird, Emily; Karatzas, Dimosthenis; Wuerger, Sophie

    2014-01-24

    An achromatic stimulus is defined as a patch of light that is devoid of any hue. This is usually achieved by asking observers to adjust the stimulus such that it looks neither red nor green and at the same time neither yellow nor blue. Despite the theoretical and practical importance of the achromatic locus, little is known about the variability in these settings. The main purpose of the current study was to evaluate whether achromatic settings were dependent on the task of the observers, namely the navigation direction in color space. Observers could either adjust the test patch along the two chromatic axes in the CIE u*v* diagram or, alternatively, navigate along the unique-hue lines. Our main result is that the navigation method affects the reliability of these achromatic settings. Observers are able to make more reliable achromatic settings when adjusting the test patch along the directions defined by the four unique hues as opposed to navigating along the main axes in the commonly used CIE u*v* chromaticity plane. This result holds across different ambient viewing conditions (Dark, Daylight, Cool White Fluorescent) and different test luminance levels (5, 20, and 50 cd/m(2)). The reduced variability in the achromatic settings is consistent with the idea that internal color representations are more aligned with the unique-hue lines than the u* and v* axes.

  18. Myc localizes to histone locus bodies during replication in Drosophila.

    Directory of Open Access Journals (Sweden)

    Kaveh Daneshvar

    Full Text Available Myc is an important protein at the center of multiple pathways required for growth and proliferation in animals. The absence of Myc is lethal in flies and mice, and its over-production is a potent inducer of over-proliferation and cancer. Myc protein is localized to the nucleus where it executes its many functions, however the specific sub-nuclear localization of Myc has rarely been reported. The work we describe here began with an observation of unexpected, punctate spots of Myc protein in certain regions of Drosophila embryos. We investigated the identity of these puncta and demonstrate that Myc is co-localized with coilin, a marker for sub-nuclear organelles known as Cajal Bodies (CBs, in embryos, larvae and ovaries. Using antibodies specific for U7 snRNP component Lsm11, we show that the majority of Myc and coilin co-localization occurs in Histone Locus Bodies (HLBs, the sites of histone mRNA transcription and processing. Furthermore, Myc localizes to HLBs only during replication in mitotic and endocycling cells, suggesting that its role there relates to replication-dependent canonical histone gene transcription. These results provide evidence that sub-nuclear localization of Myc is cell-cycle dependent and potentially important for histone mRNA production and processing.

  19. Molecular studies of deletions at the human steroid sulfatase locus

    Energy Technology Data Exchange (ETDEWEB)

    Shapiro, L.J.; Yen, P.; Pomerantz, D.; Martin, E.; Rolewic, L.; Mohandas, T. (Univ. of California, Los Angeles (USA))

    1989-11-01

    The human steroid sulfatase gene (STS) is located on the distal X chromosome short arm close to the pseudoautosomal region but in a segment of DNA that is unique to the X chromosome. In contrast to most X chromosome-encoded genes, STS expression is not extinguished during the process of X chromosome inactivation. Deficiency of STS activity produced the syndrome of X chromosome-linked ichthyosis, which is one of the most common inborn errors of metabolism in man. Approximately 90% of STS{sup {minus}} individuals have large deletions at the STS locus. The authors and others have found that the end points of such deletions are heterogeneous in their location. One recently ascertained subject was observed to have a 40-kilobase deletion that is entirely intragenic, permitting the cloning and sequencing of the deletion junction. Studies of this patient and of other X chromosome sequences in other subjects permit some insight into the mechanism(s) responsible for generating frequent deletions on the short arm of the X chromosome.

  20. Characterization of mutations at the mouse phenylalanine hydroxylase locus

    Energy Technology Data Exchange (ETDEWEB)

    McDonald, J.D.; Charlton, C.K. [Wichita State Univ., KS (United States)

    1997-02-01

    Two genetic mouse models for human phenylketonuria have been characterized by DNA sequence analysis. For each, a distinct mutation was identified within the protein coding sequence of the phenylalanine hydroxylase gene. This establishes that the mutated locus is the same as that causing human phenylketonuria and allows a comparison between these mouse phenylketonuria models and the human disease. A genotype/phenotype relationship that is strikingly similar to the human disease emerges, underscoring the similarity of phenylketonuria in mouse and man. In PAH{sup ENU1}, the phenotype is mild. The Pah{sup enu1} mutation predicts a conservative valine to alanine amino acid substitution and is located in exon 3, a gene region where serious mutations are rare in humans. In PAH{sup ENU2} the phenotype is severe. The Pah{sup enu2} mutation predicts a radical phenylalanine to serine substitution and is located in exon 7, a gene region where serious mutations are common in humans. In PAH{sup ENU2}, the sequence information was used to devise a direct genotyping system based on the creation of a new Alw26I restriction endonuclease site. 26 refs., 2 figs., 1 tab.

  1. The multifaceted roles of FLOWERING LOCUS T in plant development.

    Science.gov (United States)

    Pin, P A; Nilsson, O

    2012-10-01

    One of the key developmental processes in flowering plants is the differentiation of the shoot apical meristem into a floral meristem. This transition is regulated through the integration of environmental and endogenous stimuli, involving a complex, hierarchical signalling network. In arabidopsis, the FLOWERING LOCUS T (FT) protein, a mobile signal recognized as a major component of florigen, has a central position in mediating the onset of flowering. FT-like genes seem to be involved in regulating the floral transition in all angiosperms examined to date. Evidence from molecular evolution studies suggests that the emergence of FT-like genes coincided with the evolution of the flowering plants. Hence, the role of FT in floral promotion is conserved, but appears to be restricted to the angiosperms. Besides flowering, FT-like proteins have also been identified as major regulatory factors in a wide range of developmental processes including fruit set, vegetative growth, stomatal control and tuberization. These multifaceted roles of FT-like proteins have resulted from extensive gene duplication events, which occurred independently in nearly all modern angiosperm lineages, followed by sub- or neo-functionalization. This review assesses the plethora of roles that FT-like genes have acquired during evolution and their implications in plant diversity, adaptation and domestication.

  2. Molecular analysis of mutants of the Neurospora adenylosuccinate synthetase locus

    Indian Academy of Sciences (India)

    A. Wiest; A. J. McCarthy; R. Schnittker; K. McCluskey

    2012-08-01

    The ad-8 gene of Neurospora crassa, in addition to being used for the study of purine biology, has been extensively studied as a model for gene structure, mutagenesis and intralocus recombination. Because of this there is an extensive collection of well-characterized N. crassa ad-8 mutants in the Fungal Genetics Stock Center collection. Among these are spontaneous mutants and mutants induced with X-ray, UV or chemical mutagens. The specific lesions in these mutants have been genetically mapped at high resolution. We have sequenced the ad-8 locus from 13 of these mutants and identified the molecular nature of the mutation in each strain. We compare the historical fine-structure map to the DNA and amino acid sequence of each allele. The placement of the individual lesions in the fine-structure map was more accurate at the 5′ end of the gene and no mutants were identified in the 3′ untranslated region of this gene. We additionally analysed ad-8+ alleles in 18 N. crassa strains subjected to whole-genome sequence analysis and describe the variability among Neurospora strains and among fungi and other organisms.

  3. Relationship among prospective parents' locus of control, social desirability, and choice of psychoprophylaxis.

    Science.gov (United States)

    Windwer, C

    1977-01-01

    This study sought to determine if there is a relationship among locus of control, social desirability, and choice of psychoprophylaxis (PPM). It was hypothesized that internal locus of control and low social desirability would correlate significantly with the choice of PPM by husbands and wives; that externally controlled wives who participated in PPM would have more internally controlled husbands than externally controlled wives who participated in PPM would have more internally controlled husbands than externally controlled wives who did not participate; and that locus of control and social desirability, when taken together, would be better predictors of choice of PPM than either taken separately. Ninety-eight middle-class nulliparous couples, participant and non-participant, were studied in the seventh or eighth month of the wife's pregnancy. Rotter's I-E Scale and the Marlowe-Crowne Social Desirability Scale were used to measure locus of control and social desirability. Study findings did not support the hypotheses.

  4. A robust multiple-locus method for quantitative trait locus analysis of non-normally distributed multiple traits.

    Science.gov (United States)

    Li, Z; Möttönen, J; Sillanpää, M J

    2015-12-01

    Linear regression-based quantitative trait loci/association mapping methods such as least squares commonly assume normality of residuals. In genetics studies of plants or animals, some quantitative traits may not follow normal distribution because the data include outlying observations or data that are collected from multiple sources, and in such cases the normal regression methods may lose some statistical power to detect quantitative trait loci. In this work, we propose a robust multiple-locus regression approach for analyzing multiple quantitative traits without normality assumption. In our method, the objective function is least absolute deviation (LAD), which corresponds to the assumption of multivariate Laplace distributed residual errors. This distribution has heavier tails than the normal distribution. In addition, we adopt a group LASSO penalty to produce shrinkage estimation of the marker effects and to describe the genetic correlation among phenotypes. Our LAD-LASSO approach is less sensitive to the outliers and is more appropriate for the analysis of data with skewedly distributed phenotypes. Another application of our robust approach is on missing phenotype problem in multiple-trait analysis, where the missing phenotype items can simply be filled with some extreme values, and be treated as outliers. The efficiency of the LAD-LASSO approach is illustrated on both simulated and real data sets.

  5. Relationship between Dental Anxiety and Health Locus of Control among Physiotherapy Students

    Directory of Open Access Journals (Sweden)

    Pooja Agarwal

    2013-01-01

    Materials & Method: A total of 152 students participated in the study. Dental anxiety was assessed using the 5 item Modified Dental Anxiety Scale (MDAS and Locus of Control was assessed using the 18 item Multidimensional Health Locus of Control (MHLC scale. Results: A Statistically significant positive correlation was found between the internal dimension of MHLC and dental anxiety. Conclusions: HLC was found to play an important role in predicting the dental anxiety among physiotherapy students.

  6. Analysis of genes for alcoholism using two-disease-locus models

    OpenAIRE

    Shete Sanjay; Wu Chih-Chieh

    2005-01-01

    Abstract Using model-based two-locus methods for mapping genes, we analyzed the family data from the Collaborative Study on the Genetics of Alcoholism. Microsatellite data from 143 families ascertained through having three or more individuals affected with alcohol dependence were used for this investigation. Four regions showing evidence for linkage were identified using single-locus models from previous investigations. We investigated the genetic linkage, pattern of disease inheritance, and ...

  7. Hysteresis zone or locus - Aerodynamic of bulbous based bodies at low speeds

    Science.gov (United States)

    Covert, E. E.

    1979-01-01

    Experimental data are presented which seem to suggest that a well-defined hysteresis locus on bulbous based bodies at low speeds does not exist. Instead, if the experiment is repeated several times, the entire hysteresis region seems to fill with data rather than trace out a specific hysteresis locus. Data obtained on an oscillating model even at low reduced frequencies may be well defined but when applied to arbitrary motion lead to less accurate results than desired.

  8. Biofeedback and meditation: effects on muscle tension and locus of control.

    Science.gov (United States)

    Zaichkowsky, L D; Kamen, R

    1978-06-01

    A total of 48 subjects participated in a relaxation experiment to determine whether frontalis muscle EMG biofeedback, Transcendental Meditation, and meditation (Benson technique) produced decreased muscle tension and concomitant changes in locus of control. All three treatments resulted in significant decreases in frontalis muscle tension when compared to a control. Concomitant changes towards an internal locus of control occurred only in the subjects given biofeedback.

  9. Relationship of Metacognition Learning Strategy and Locus of Control with Academic Achievement of Students

    OpenAIRE

    Mohammadi Y; Kaykha A; Sadeghi A; Kazemi S; Raeisoon MR

    2015-01-01

    Aims: Academic achievement is one of the main assessment factors in the higher education system. Metacognitive learning strategy and locus of control are the main factors affecting the students’ academic achievement. The aim of this study was to investigate the correlation between metacognitive learning strategy and locus of control and the students’ academic achievement.  Instrument & Methods: In the descriptive-analytic study, 335 students of Birjand University of Medic...

  10. The Interrelationship among Locus of Control, Sexual Satisfaction and Marital Satisfaction

    OpenAIRE

    2015-01-01

    The primary goal of the present study is to examine the interrelationships among locus of control, sexual satisfaction and marital satisfaction. In the current study, a sample which was composed of 200 married persons was investigated. Research tools include locus of control, sexual satisfaction and marital satisfaction. For data analysis, correlation and independent hierarchical multiple regression analyses were used to determine the relationships between the predictor variables and criterio...

  11. Fine mapping of the NRG1 Hirschsprung's disease locus.

    Directory of Open Access Journals (Sweden)

    Clara Sze-Man Tang

    Full Text Available The primary pathology of Hirschsprung's disease (HSCR, colon aganglionosis is the absence of ganglia in variable lengths of the hindgut, resulting in functional obstruction. HSCR is attributed to a failure of migration of the enteric ganglion precursors along the developing gut. RET is a key regulator of the development of the enteric nervous system (ENS and the major HSCR-causing gene. Yet the reduced penetrance of RET DNA HSCR-associated variants together with the phenotypic variability suggest the involvement of additional genes in the disease. Through a genome-wide association study, we uncovered a ∼350 kb HSCR-associated region encompassing part of the neuregulin-1 gene (NRG1. To identify the causal NRG1 variants contributing to HSCR, we genotyped 243 SNPs variants on 343 ethnic Chinese HSCR patients and 359 controls. Genotype analysis coupled with imputation narrowed down the HSCR-associated region to 21 kb, with four of the most associated SNPs (rs10088313, rs10094655, rs4624987, and rs3884552 mapping to the NRG1 promoter. We investigated whether there was correlation between the genotype at the rs10088313 locus and the amount of NRG1 expressed in human gut tissues (40 patients and 21 controls and found differences in expression as a function of genotype. We also found significant differences in NRG1 expression levels between diseased and control individuals bearing the same rs10088313 risk genotype. This indicates that the effects of NRG1 common variants are likely to depend on other alleles or epigenetic factors present in the patients and would account for the variability in the genetic predisposition to HSCR.

  12. Evidence for meiotic drive at the myotonic dystrophy locus

    Energy Technology Data Exchange (ETDEWEB)

    Shaw, A.M.; Barnetson, R.A.; Phillips, M.F. [Institute of Medical Genetics, Wales (United Kingdom)] [and others

    1994-09-01

    Myotonic dystrophy (DM), an autosomal dominant disorder, is the most common form of adult muscular dystrophy, affecting at least 1 in 8000 of the population. It is a multisystemic disorder, primarily characterized by myotonia, muscle wasting and cataract. The molecular basis of DM is an expanded CTG repeat located within the 3{prime} untranslated region of a putative serine-threonine protein kinase on chromosome 19q13.3. DM exhibits anticipation, that is, with successive generations there is increasing disease severity and earlier age of onset. This mechanism and the fact that the origin of the disease has been attributed to one or a small number of founder chromosomes suggests that, in time, DM should die out. Meiotic drive has been described as a way in which certain alleles are transmitted to succeeding generations in preference to others: preferential transmission of large CTG alleles may account for their continued existence in the gene pool. There is evidence that a CTG allele with > 19 repeats may gradually increase in repeat number over many generations until it is sufficiently large to give a DM phenotype. We report a study of 495 transmissions from individuals heterozygous for the CTG repeat and with repeat numbers within the normal range (5-30). Alleles were simply classified as large or small relative to the other allele in an individual. Of 242 male meioses, 126 transmissions from parent to child were of the larger allele to their offspring (57.7%, p=0.014). This shows that there is strong evidence for meiotic drive favoring the transmission of the larger DM allele in unaffected individuals. Contrary to a previous report of meiotic drive in the male, we have shown that females preferentially transmit the larger DM allele. Taken together, the data suggest the occurrence of meiotic drive in both males and females in this locus.

  13. Role of TRAV locus in low caries experience.

    Science.gov (United States)

    Briseño-Ruiz, Jessica; Shimizu, Takehiko; Deeley, Kathleen; Dizak, Piper M; Ruff, Timothy D; Faraco, Italo M; Poletta, Fernando A; Brancher, João A; Pecharki, Giovana D; Küchler, Erika C; Tannure, Patricia N; Lips, Andrea; Vieira, Thays C S; Patir, Asli; Koruyucu, Mine; Mereb, Juan C; Resick, Judith M; Brandon, Carla A; Letra, Ariadne; Silva, Renato M; Cooper, Margaret E; Seymen, Figen; Costa, Marcelo C; Granjeiro, José M; Trevilatto, Paula C; Orioli, Iêda M; Castilla, Eduardo E; Marazita, Mary L; Vieira, Alexandre R

    2013-09-01

    Caries is the most common chronic, multifactorial disease in the world today; and little is still known about the genetic factors influencing susceptibility. Our previous genome-wide linkage scan has identified five loci related to caries susceptibility: 5q13.3, 13q31.1, 14q11.2, 14q 24.3, and Xq27. In the present study, we fine mapped the 14q11.2 locus to identify genetic contributors to caries susceptibility. Four hundred seventy-seven subjects from 72 pedigrees with similar cultural and behavioral habits and limited access to dental care living in the Philippines were studied. An additional 387 DNA samples from unrelated individuals were used to determine allele frequencies. For replication purposes, a total of 1,446 independent subjects from four different populations were analyzed based on their caries experience (low versus high). Forty-eight markers in 14q11.2 were genotyped using TaqMan chemistry. Transmission disequilibrium test was used to detect over transmission of alleles in the Filipino families, and Chi-square, Fisher's exact and logistic regression were used to test for association between low caries experience and variant alleles in the replication data sets. We finally assessed the mRNA expression of TRAV4 in the saliva of 143 study subjects. In the Filipino families, statistically significant associations were found between low caries experience and markers in TRAV4. We were able to replicate these results in the populations studied that were characteristically from underserved areas. Direct sequencing of 22 subjects carrying the associated alleles detects one missense mutation (Y30R) that is predicted to be probably damaging. Finally, we observed higher expression in children and teenagers with low caries experience, correlating with specific alleles in TRAV4. Our results suggest that TRAV4 may have a role in protecting against caries.

  14. Locus-specific ribosomal RNA gene silencing in nucleolar dominance.

    Directory of Open Access Journals (Sweden)

    Michelle S Lewis

    Full Text Available The silencing of one parental set of rRNA genes in a genetic hybrid is an epigenetic phenomenon known as nucleolar dominance. We showed previously that silencing is restricted to the nucleolus organizer regions (NORs, the loci where rRNA genes are tandemly arrayed, and does not spread to or from neighboring protein-coding genes. One hypothesis is that nucleolar dominance is the net result of hundreds of silencing events acting one rRNA gene at a time. A prediction of this hypothesis is that rRNA gene silencing should occur independent of chromosomal location. An alternative hypothesis is that the regulatory unit in nucleolar dominance is the NOR, rather than each individual rRNA gene, in which case NOR localization may be essential for rRNA gene silencing. To test these alternative hypotheses, we examined the fates of rRNA transgenes integrated at ectopic locations. The transgenes were accurately transcribed in all independent transgenic Arabidopsis thaliana lines tested, indicating that NOR localization is not required for rRNA gene expression. Upon crossing the transgenic A. thaliana lines as ovule parents with A. lyrata to form F1 hybrids, a new system for the study of nucleolar dominance, the endogenous rRNA genes located within the A. thaliana NORs are silenced. However, rRNA transgenes escaped silencing in multiple independent hybrids. Collectively, our data suggest that rRNA gene activation can occur in a gene-autonomous fashion, independent of chromosomal location, whereas rRNA gene silencing in nucleolar dominance is locus-dependent.

  15. Forebrain GABAergic projections to locus coeruleus in mouse.

    Science.gov (United States)

    Dimitrov, Eugene L; Yanagawa, Yuchio; Usdin, Ted B

    2013-07-01

    The noradrenergic locus coeruleus (LC) regulates arousal, memory, sympathetic nervous system activity, and pain. Forebrain projections to LC have been characterized in rat, cat, and primates, but not systematically in mouse. We surveyed mouse forebrain LC-projecting neurons by examining retrogradely labeled cells following LC iontophoresis of Fluoro-Gold and anterograde LC labeling after forebrain injection of biotinylated dextran amine or viral tracer. Similar to other species, the central amygdalar nucleus (CAmy), anterior hypothalamus, paraventricular nucleus, and posterior lateral hypothalamic area (PLH) provide major LC inputs. By using mice expressing green fluorescent protein in γ-aminobutyric acid (GABA)ergic neurons, we found that more than one-third of LC-projecting CAmy and PLH neurons are GABAergic. LC colocalization of biotinylated dextran amine, following CAmy or PLH injection, with either green fluorescent protein or glutamic acid decarboxylase (GAD)65/67 immunoreactivity confirmed these GABAergic projections. CAmy injection of adeno-associated virus encoding channelrhodopsin-2-Venus showed similar fiber labeling and association with GAD65/67-immunoreactive (ir) and tyrosine hydroxylase (TH)-ir neurons. CAmy and PLH projections were densest in a pericoerulear zone, but many fibers entered the LC proper. Close apposition between CAmy GABAergic projections and TH-ir processes suggests that CAmy GABAergic neurons may directly inhibit noradrenergic principal neurons. Direct LC neuron targeting was confirmed by anterograde transneuronal labeling of LC TH-ir neurons following CAmy or PLH injection of a herpes virus that expresses red fluorescent protein following activation by Cre recombinase in mice that express Cre recombinase in GABAergic neurons. This description of GABAergic projections from the CAmy and PLH to the LC clarifies important forebrain sources of inhibitory control of central nervous system noradrenergic activity.

  16. Searching for a major locus for male pattern baldness (MPB)

    Energy Technology Data Exchange (ETDEWEB)

    Anker, R.; Eisen, A.Z.; Donis-Keller, H. [Washington Univ. School of Medicine, St. Louis, MO (United States)

    1994-09-01

    Male pattern baldness (MPB) is a common trait in post-pubertal males. Approximately 50% of adult males present some degree of MPB by age 50. According to the classification provided by Hamilton in 1951 and modified by Norwood in 1975, the trait itself is a continuum that ranges from mild (Type I) to severe (Type VII) cases. In addition, there is extensive variability for the age of onset. The role of androgens in allowing the expression of this trait in males has been well established. This phenotype is uncommonly expressed in females. The high prevalence of the trait, the distribution of MPB as a continuous trait, and several non-allelic mutations identified in the mouse capable of affecting hair pattern, suggest that MPB is genetically heterogeneous. In order to reduce the probability of multiple non-allelic MPB genes within a pedigree, we selected 9 families in which MPB appears to segregate exclusively through the paternal lineage as compared to bilineal pedigrees. There are 32 males expressing this phenotype and females are treated as phenotype unknown. In general, affected individuals expressed the trait before 30 years of age with a severity of at least Type III or IV. We assumed an autosomal dominant model, with a gene frequency of 1/20 for the affected allele, and 90% penetrance. Simulation studies using the SLINK program with these pedigrees showed that these families would be sufficient to detect linkage under the assumption of a single major locus. If heterogeneity is present, the current resource does not have sufficient power to detect linkage at a statistically significant level, although candidate regions of the genome could be identified for further studies with additional pedigrees. Using 53 highly informative microsatellite markers, and a subset of 7 families, we have screened 30% of the genome. This search included several regions where candidate genes for MPB are located.

  17. Association of the GNAS Locus with Severe Malaria

    Science.gov (United States)

    Auburn, Sarah; Diakite, Mahamadou; Fry, Andrew E.; Ghansah, Anita; Campino, Susana; Richardson, Anna; Jallow, Muminatou; Sisay-Joof, Fatou; Pinder, Margaret; Griffiths, Michael J.; Peshu, Norbert; Williams, Thomas N.; Marsh, Kevin; Molyneux, Malcolm E.; Taylor, Terrie E.; Koram, Kwadwo A.; Oduro, Abraham R.; Rogers, William O.; Rockett, Kirk A.; Haldar, Kasturi; Kwiatkowski, Dominic P.

    2009-01-01

    Functional studies have demonstrated an interaction between the stimulatory G protein alpha subunit (G-alpha-s) and the malaria parasite at a cellular level. Obstruction of signal transduction via the erythrocyte G-alpha-s subunit reduced invasion by P.falciparum parasites. We sought to determine whether this signal pathway had an impact at the disease level by testing polymorphisms in the gene encoding G-alpha-s (GNAS) for association with severe malaria in a large multi-centre study encompassing family and case-control studies from The Gambia, Kenya and Malawi, and a case-control study from Ghana. We gained power to detect association using meta-analysis across the 7 studies, with an overall sample size approximating 4000 cases and 4000 controls. Out of 12 SNPs investigated in the 19kb GNAS region, 4 presented signals of association (P<0.05) with severe malaria. The strongest single locus association demonstrated an odds ratio of 1.13 (1.05-1.21), P=0.001. Three of the loci presenting significant associations were clustered at the 5-prime end of the GNAS gene. Accordingly, haplotypes constructed from these loci demonstrated significant associations with severe malaria (OR=0.88 (0.81-0.96), P=0.005; and OR=1.12 (1.03-1.20), P=0.005). The evidence presented here indicates that the influence of G-alpha-s on erythrocyte invasion efficacy may, indeed, alter individual susceptibility to disease. PMID:18951142

  18. The Shc locus regulates insulin signaling and adiposity in mammals

    Science.gov (United States)

    Tomilov, Alexey A.; Ramsey, Jon J.; Hagopian, Kevork; Giorgio, Marco; Kim, Kyoungmi M.; Lam, Adam; Migliaccio, Enrica; Lloyd, Kent C.; Berniakovich, Ina; Prolla, Tomas A.; Pelicci, PierGiuseppe; Cortopassi, Gino A.

    2014-01-01

    Summary Longevity of a p66Shc knockout strain (ShcP) was previously attributed to increased stress resistance and altered mitochondria. Microarrays of ShcP tissues indicated alterations in insulin signaling. Consistent with this observation, ShcP mice were more insulin sensitive and glucose tolerant at organismal and tissue levels, as was a novel p66Shc knockout (ShcL). Increasing and decreasing Shc expression in cell lines decreased and increased insulin sensitivity, respectively – consistent with p66Shc's function as a repressor of insulin signaling. However, differences between the two p66Shc knockout strains were also observed. ShcL mice were fatter and susceptible to fatty diets, and their fat was more insulin sensitive than controls. On the other hand, ShcP mice were leaner and resisted fatty diets, and their adipose was less insulin sensitive than controls. ShcL and ShcP strains are both highly inbred on the C57Bl/6 background, so we investigated gene expression at the Shc locus, which encodes three isoforms, p66, p52, and p46. Isoform p66 is absent in both strains; thus, the remaining difference to which to attribute the ‘lean’ phenotype is expression of the other two isoforms. ShcL mice have a precise deletion of p66Shc and normal expression of p52 and p46Shc isoforms in all tissues; thus, a simple deletion of p66Shc results in a ‘fat’ phenotype. However, ShcP mice in addition to p66Shc deletion have a fourfold increase in p46Shc expression in white fat. Thus, p46Shc overexpression in fat, rather than p66Shc deletion, is the likely cause of decreased adiposity and reduced insulin sensitivity in the fat of ShcP mice, which has implications for the longevity of the strain. PMID:21040401

  19. The Lbw2 locus promotes autoimmune hemolytic anemia.

    Science.gov (United States)

    Scatizzi, John C; Haraldsson, Maria K; Pollard, K Michael; Theofilopoulos, Argyrios N; Kono, Dwight H

    2012-04-01

    The lupus-prone New Zealand Black (NZB) strain uniquely develops a genetically imposed severe spontaneous autoimmune hemolytic anemia (AIHA) that is very similar to the corresponding human disease. Previous studies have mapped anti-erythrocyte Ab (AEA)-promoting NZB loci to several chromosomal locations, including chromosome 4; however, none of these have been analyzed with interval congenics. In this study, we used NZB.NZW-Lbw2 congenic (designated Lbw2 congenic) mice containing an introgressed fragment of New Zealand White (NZW) on chromosome 4 encompassing Lbw2, a locus previously linked to survival, glomerulonephritis, and splenomegaly, to investigate its role in AIHA. Lbw2 congenic mice exhibited marked reductions in AEAs and splenomegaly but not in anti-nuclear Abs. Furthermore, Lbw2 congenics had greater numbers of marginal zone B cells and reduced expansion of peritoneal cells, particularly the B-1a cell subset at early ages, but no reduction in B cell response to LPS. Analysis of a panel of subinterval congenic mice showed that the full effect of Lbw2 on AEA production was dependent on three subloci, with splenomegaly mapping to two of the subloci and expansions of peritoneal cell populations, including B-1a cells to one. These results directly demonstrated the presence of AEA-specific promoting genes on NZB chromosome 4, documented a marked influence of background genes on autoimmune phenotypes related to Lbw2, and further refined the locations of the underlying genetic variants. Delineation of the Lbw2 genes should yield new insights into both the pathogenesis of AIHA and the nature of epistatic interactions of lupus-modifying genetic variants.

  20. First multi-locus sequence typing scheme for Arcobacter spp.

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    Wang Guilin

    2009-09-01

    Full Text Available Abstract Background Arcobacter spp. are a common contaminant of food and water, and some species, primarily A. butzleri and A. cryaerophilus, have been isolated increasingly from human diarrheal stool samples. Here, we describe the first Arcobacter multilocus sequence typing (MLST method for A. butzleri, A. cryaerophilus, A. skirrowii, A. cibarius and A. thereius. Results A sample set of 374 arcobacters, including 275 A. butzleri, 72 A. cryaerophilus, 15 A. skirrowii and 8 A. cibarius isolates from a wide variety of geographic locations and sources, was typed in this study. Additionally, this sample set contained four strains representing a new Arcobacter species, A. thereius. The seven loci used in the four-species Arcobacter MLST method are the same as those employed previously in C. jejuni, C. coli, C. helveticus and C. fetus (i.e. aspA, atpA(uncA, glnA, gltA, glyA, pgm and tkt. A large number of alleles were identified at each locus with the majority of isolates containing a unique sequence type. All Arcobacter isolates typed in this study contain two glyA genes, one linked to lysS (glyA1 and the other linked to ada (glyA2. glyA1 was incorporated into the Arcobacter MLST method while glyA2 was not because it did not increase substantially the level of discrimination. Conclusion No association of MLST alleles or sequence types with host or geographical source was observed with this sample set. Nevertheless, the large number of identified alleles and sequence types indicate that this MLST method will prove useful in both Arcobacter strain discrimination and in epidemiological studies of sporadic Arcobacter-related gastroenteritis. A new Arcobacter MLST database was created http://pubmlst.org/arcobacter/; allele and ST data generated in this study were deposited in this database and are available online.

  1. The locus of impairment in English developmental letter position dyslexia

    Directory of Open Access Journals (Sweden)

    Yvette eKezilas

    2014-06-01

    Full Text Available Many children with reading difficulties display phonological deficits and struggle to acquire nonlexical reading skills. However, not all children with reading difficulties have these problems, such as children with selective Letter Position Dyslexia (LPD, who make excessive migration errors (such as reading slime as ‘smile’. Previous research has explored three possible loci for the deficit – the phonological output buffer, the orthographic input lexicon, and the orthographic-visual analysis stage of reading. While there is compelling evidence against a phonological output buffer and orthographic input lexicon deficit account of English LPD, the evidence in support of an orthographic-visual analysis deficit is currently limited. In this multiple single-case study with three English speaking children with developmental LPD we aimed to both replicate and extend previous findings regarding the locus of impairment in English LPD. First, we ruled out a phonological output buffer and an orthographic input lexicon deficit by administering tasks that directly assess phonological processing and lexical guessing. We then went on to directly assess whether or not children with LPD have an orthographic-visual analysis deficit by modifying two tasks that have previously been used to localize processing at this level: a same-different decision task and a nonword reading task. The results from these tasks indicate that LPD is most likely caused by a deficit specific to the coding of letter positions at the orthographic-visual analysis stage of reading. These findings provide further evidence for the heterogeneity of dyslexia and its underlying causes.

  2. The locus of impairment in English developmental letter position dyslexia.

    Science.gov (United States)

    Kezilas, Yvette; Kohnen, Saskia; McKague, Meredith; Castles, Anne

    2014-01-01

    Many children with reading difficulties display phonological deficits and struggle to acquire non-lexical reading skills. However, not all children with reading difficulties have these problems, such as children with selective letter position dyslexia (LPD), who make excessive migration errors (such as reading slime as "smile"). Previous research has explored three possible loci for the deficit - the phonological output buffer, the orthographic input lexicon, and the orthographic-visual analysis stage of reading. While there is compelling evidence against a phonological output buffer and orthographic input lexicon deficit account of English LPD, the evidence in support of an orthographic-visual analysis deficit is currently limited. In this multiple single-case study with three English-speaking children with developmental LPD, we aimed to both replicate and extend previous findings regarding the locus of impairment in English LPD. First, we ruled out a phonological output buffer and an orthographic input lexicon deficit by administering tasks that directly assess phonological processing and lexical guessing. We then went on to directly assess whether or not children with LPD have an orthographic-visual analysis deficit by modifying two tasks that have previously been used to localize processing at this level: a same-different decision task and a non-word reading task. The results from these tasks indicate that LPD is most likely caused by a deficit specific to the coding of letter positions at the orthographic-visual analysis stage of reading. These findings provide further evidence for the heterogeneity of dyslexia and its underlying causes.

  3. Duplication of Locus Coding of Malate Dehydrogenase in Populus tomentosa Carr.

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    Horizontal starch-gel electrophoresis was used to study crude enzyme extraction from young leaves of 234 clones of Populus tomentosa Carr. selected from nine provenances in North China. Ten enzyme systems were resolved. One hundred and fifty-six clones showing unusual allozyme band patterns at locus Mdh-1 were found. Three allozyme bands at locus Mdh-1 were 9:6:1 in concentration. Further studies on the electrophoretic patterns of ground mixed pollen extraction of 30 male clones selected at random from the 156 clones were conducted and it was found that allozyme bands at locus Mdh-1 were composed of two dark-stained bands and a weak band. Only one group of the malate dehydrogenase (MDH) zymogram composed of two bands was obtained from the electrophoretic segregation of pollen leachate of the same clones. A comparison of the electrophoretic patterns one another suggested that the locus Mdh-1 coding malate dehydrogenase in diploid species of P. tomentosa was duplicated. The duplicate gene locus possessed three same alleles and was located in mitochondria. The locus duplication of alleles coding malate dehydrogenase in P. tomentosa was discovered and reported for the first time.

  4. The class of the locus of intermediate Jacobians of cubic threefolds

    CERN Document Server

    Grushevsky, Samuel

    2011-01-01

    We study the locus of intermediate Jacobians of cubic threefolds within the moduli space of complex principally polarized abelian fivefolds, and its generalization to arbitrary genus - the locus of abelian varieties with a singular odd two-torsion point on the theta divisor. Assuming that this locus has expected codimension (which we show to be true for genus up to 5), we compute the class of this locus, and of is closure in the perfect cone toroidal compactification, in the Chow, homology, and the tautological ring. We work out the cases of genus up to 5 in detail, obtaining explicit expressions for the classes of the closures of the locus of products of an elliptic curve and a hyperelliptic genus 3 curve, in moduli of principally polarized abelian fourfolds, and of the locus of intermediate Jacobians in genus 5. In the course of our computation we also deal with various intersections of boundary divisors of a level toroidal compactification, which is of independent interest in understanding the cohomology a...

  5. Physical map and one-megabase sequencing of the human immunoglobulin lambda locus

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    Geraldo A.S. Passos Jr.

    1998-06-01

    Full Text Available The human immunoglobulin lambda (IGL locus is located on chromosome 22q11.1-q11.2 and contains the genes responsible for the immunoglobulin lambda light chains. This locus was recently mapped (physical map and its 1-Mb DNA totally sequenced. In this review we focus on the characterization of the v-lambda genes, its chromosomal location, genomics and sequencing of the IGL locus.O locus IGL humano está localizado no cromosomo 22q11.1-q11.2 e contém os genes responsáveis pelas cadeias leves de imunoglobulina tipo lambda. Este locus foi recentemente mapeado (mapa físico e seu 1 Mb DNA totalmente sequenciado. Nesta revisão focamos os principais resultados de caracterização dos genes v-lambda, sua localização cromossômica, a genômica e seqüenciamento do locus IGL.

  6. Locus heterogeneity disease genes encode proteins with high interconnectivity in the human protein interaction network.

    Science.gov (United States)

    Keith, Benjamin P; Robertson, David L; Hentges, Kathryn E

    2014-01-01

    Mutations in genes potentially lead to a number of genetic diseases with differing severity. These disease genes have been the focus of research in recent years showing that the disease gene population as a whole is not homogeneous, and can be categorized according to their interactions. Locus heterogeneity describes a single disorder caused by mutations in different genes each acting individually to cause the same disease. Using datasets of experimentally derived human disease genes and protein interactions, we created a protein interaction network to investigate the relationships between the products of genes associated with a disease displaying locus heterogeneity, and use network parameters to suggest properties that distinguish these disease genes from the overall disease gene population. Through the manual curation of known causative genes of 100 diseases displaying locus heterogeneity and 397 single-gene Mendelian disorders, we use network parameters to show that our locus heterogeneity network displays distinct properties from the global disease network and a Mendelian network. Using the global human proteome, through random simulation of the network we show that heterogeneous genes display significant interconnectivity. Further topological analysis of this network revealed clustering of locus heterogeneity genes that cause identical disorders, indicating that these disease genes are involved in similar biological processes. We then use this information to suggest additional genes that may contribute to diseases with locus heterogeneity.

  7. Comparing health locus of control in patients with Spasmodic Dysphonia, Functional Dysphonia and Nonlaryngeal Dystonia.

    Science.gov (United States)

    Haselden, Karen; Powell, Theresa; Drinnan, Mike; Carding, Paul

    2009-11-01

    Locus of Control (LoC) refers to an individuals' perception of whether they are in control of life events. Health Locus of Control refers to whether someone feels they have influence over their health. Health Locus of Control has not been studied in any depth in voice-disordered patients. The objective of this study was to examine Health Locus of Control in three patient groups: (1) Spasmodic Dysphonia, (2) Functional Dysphonia and (3) a nondysphonic group with Nonlaryngeal Dystonia. LoC was measured and compared in a total of 57 patients using the Multidimensional Health Locus of Control Scales (diagnostic specific) Form C. Internal, Chance, and Powerful others LoC were measured and comparisons were made using one-way analysis of variance. Contrary to expectations Internal LoC was found to be significantly higher in the Functional Dysphonia group when compared to the other two groups. There was no significant difference between the groups in Chance or Powerful others LoC. The two organic groups, Spasmodic Dysphonia and Nonlaryngeal Dystonia, were more alike in Internal Health Locus of Control than the Functional Dysphonia group. The diagnostic nature of the groups was reflected in their LoC scores rather than their voice loss. These results contribute to the debate about the etiology of Spasmodic Dysphonia and will be of interest to those involved in the psychology of voice and those managing voice-disordered patients.

  8. Relationship of Metacognition Learning Strategy and Locus of Control with Academic Achievement of Students

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    Mohammadi Y

    2015-12-01

    Full Text Available Aims: Academic achievement is one of the main assessment factors in the higher education system. Metacognitive learning strategy and locus of control are the main factors affecting the students’ academic achievement. The aim of this study was to investigate the correlation between metacognitive learning strategy and locus of control and the students’ academic achievement.  Instrument & Methods: In the descriptive-analytic study, 335 students of Birjand University of Medical sciences were selected based on Krejcie-Morgan Table and via Stratified Random Sampling Method in 2014-15 academic year. The study tools were Self-regulating Learning Strategies Questionnaire, Locus of Control Survey, and students’ GPA as academic achievement component. Data was analyzed in SPSS 14 software using Pearson Correlation, Independent T, and One-way ANOVA tests. Findings: There was a positive and significant correlation between the dimensions of meta-cognitive learning strategy and internal locus of control and academic achievement. Nevertheless, there was a negative and significant correlation between meta-cognitive learning strategies and external locus of control (p0.05. There was a significant correlation between the students’ academic achievements based on gender. However, based on age and faculty, it was not significant.    Conclusion: Two important factors affecting learning enhancement and academic achievement in the students are meta-cognitive learning strategy and locus of control.

  9. Locus Of Control - Predictor Of Health And Subjective Well – Being

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    Svetlana Popova

    2012-10-01

    Full Text Available The article presents results of a study of the relationship 'locus of control - health and subjective well-being. In a heterogeneous sample (N = 239 in the stage of youth (19-30 years shall be established: locus of control determines 11.56% of the changes in the assessment of health, changes in health contribute to 12.82% of the variation in assessment of happiness and 6.10% in the measurement of life satisfaction. Young people with an internal locus of control are healthier, happier and more satisfied with their lives than those with an external locus of control. In a study of cause - effect relationship is established that internal locus of control determines a healthier lifestyle. Inadequate health care, more severe risk factors (stress, unhealthy diet, inadequate sleep, smoking among young people with an external locus of control, outline prospects for greater vulnerability of this group of the population of the so called "Diseases of modern society." Most preferred activities of young people beneficial to their health are: walking, relaxation, hobbies and sports, and this is the way to state "flow" (activity of happiness and highlights the positive experiences in health. 

  10. The stability of locus equation slopes across stop consonant voicing/aspiration

    Science.gov (United States)

    Sussman, Harvey M.; Modarresi, Golnaz

    2001-05-01

    The consistency of locus equation slopes as phonetic descriptors of stop place in CV sequences across voiced and voiceless aspirated stops was explored in the speech of five male speakers of American English and two male speakers of Persian. Using traditional locus equation measurement sites for F2 onsets, voiceless labial and coronal stops had significantly lower locus equation slopes relative to their voiced counterparts, whereas velars failed to show voicing differences. When locus equations were derived using F2 onsets for voiced stops that were measured closer to the stop release burst, comparable to the protocol for measuring voiceless aspirated stops, no significant effects of voicing/aspiration on locus equation slopes were observed. This methodological factor, rather than an underlying phonetic-based explanation, provides a reasonable account for the observed flatter locus equation slopes of voiceless labial and coronal stops relative to voiced cognates reported in previous studies [Molis et al., J. Acoust. Soc. Am. 95, 2925 (1994); O. Engstrand and B. Lindblom, PHONUM 4, 101-104]. [Work supported by NIH.

  11. Genome organization of the tomato sun locus and characterization of the unusual retrotransposon Rider.

    Science.gov (United States)

    Jiang, Ning; Gao, Dongying; Xiao, Han; van der Knaap, Esther

    2009-10-01

    DNA sequences provide useful insights into genome structure and organization as well as evolution of species. We report on a detailed analysis of the locus surrounding the tomato (Solanum lycopersicum) fruit-shape gene SUN to determine the driving force and genome environment that foster the appearance of novel phenotypes. The gene density at the sun locus is similar to that described in other euchromatic portions of the tomato genome despite the relatively high number of transposable elements. Genes at the sun locus include protein-coding as well as RNA genes, are small in size, and belong to families that were duplicated at the locus an estimated 5-74 million years ago. In general, the DNA transposons at the sun locus are older than the RNA transposons, and their insertion pre-dates the speciation of S. lycopersicum and S. pimpinellifolium. Gene redundancy and large intergenic regions may explain the tolerance of the sun locus to frequent rearrangements and transpositions. The most recent transposition event at the sun locus involved Rider, a recently discovered high-copy retrotransposon. Rider probably arose early during the speciation of tomato. The element inserts into or near to genes and may still be active, which are unusual features for a high-copy element. Rider full-length and read-through transcripts past the typical transcription termination stop are detected, and the latter are required for mobilizing nearby sequences. Rider activity has resulted in an altered phenotype in three known cases, and may therefore have played an important role in tomato evolution and domestication.

  12. Functional analysis of the TRIB1 associated locus linked to plasma triglycerides and coronary artery disease.

    Science.gov (United States)

    Douvris, Adrianna; Soubeyrand, Sébastien; Naing, Thet; Martinuk, Amy; Nikpay, Majid; Williams, Andrew; Buick, Julie; Yauk, Carole; McPherson, Ruth

    2014-06-03

    The TRIB1 locus has been linked to hepatic triglyceride metabolism in mice and to plasma triglycerides and coronary artery disease in humans. The lipid-associated single nucleotide polymorphisms (SNPs), identified by genome-wide association studies, are located ≈30 kb downstream from TRIB1, suggesting complex regulatory effects on genes or pathways relevant to hepatic triglyceride metabolism. The goal of this study was to investigate the functional relationship between common SNPs at the TRIB1 locus and plasma lipid traits. Characterization of the risk locus reveals that it encompasses a gene, TRIB1-associated locus (TRIBAL), composed of a well-conserved promoter region and an alternatively spliced transcript. Bioinformatic analysis and resequencing identified a single SNP, rs2001844, within the promoter region that associates with increased plasma triglycerides and reduced high-density lipoprotein cholesterol and coronary artery disease risk. Further, correction for triglycerides as a covariate indicated that the genome-wide association studies association is largely dependent on triglycerides. In addition, we show that rs2001844 is an expression trait locus (eQTL) for TRIB1 expression in blood and alters TRIBAL promoter activity in a reporter assay model. The TRIBAL transcript has features typical of long noncoding RNAs, including poor sequence conservation. Modulation of TRIBAL expression had limited impact on either TRIB1 or lipid regulatory genes mRNA levels in human hepatocyte models. In contrast, TRIB1 knockdown markedly increased TRIBAL expression in HepG2 cells and primary human hepatocytes. These studies demonstrate an interplay between a novel locus, TRIBAL, and TRIB1. TRIBAL is located in the genome-wide association studies identified risk locus, responds to altered expression of TRIB1, harbors a risk SNP that is an eQTL for TRIB1 expression, and associates with plasma triglyceride concentrations. © 2014 The Authors. Published on behalf of the

  13. The Impact of Locus of Control and Controlling Language on Psychological Reactance and Ad Effectiveness in Health Communication.

    Science.gov (United States)

    Xu, Jie

    2016-11-08

    Based on two theoretical models-psychological reactance theory (PRT) and locus of control-this study examines the individual and joint effects of locus of control and controlling language on young adults' information processing. Two experimental studies on anti-driving-after-drinking (anti-DAD) and antismoking public service announcements (PSAs) were conducted that were conceptual replications of each other. Both studies afforded evidence that those with external locus of control were more involved in risky behaviors. There was a consistent interaction between locus of control and controlling language, such that those with internal locus of control were more sensitive to this message feature compared to those with external locus of control. Controlling language was found to increase reactance. The theoretical and managerial implications for health communication are elaborated. Limitations and directions for future research are also outlined.

  14. Linkage disequilibrium at the APA insecticidal seed protein locus of common bean (Phaseolus vulgaris L.).

    Science.gov (United States)

    Blair, Matthew W; Prieto, Sergio; Díaz, Lucy M; Buendía, Héctor F; Cardona, César

    2010-04-29

    An interesting seed protein family with a role in preventing insect herbivory is the multi-gene, APA family encoding the alpha-amylase inhibitor, phytohemagglutinin and arcelin proteins of common bean (Phaseolus vulgaris). Variability for this gene family exists and has been exploited to breed for insect resistance. For example, the arcelin locus has been successfully transferred from wild to cultivated common bean genotypes to provide resistance against the bruchid species Zabrotes subfasciatus although the process has been hampered by a lack of genetic tools for and understanding about the locus. In this study, we analyzed linkage disequilibrium (LD) between microsatellite markers at the APA locus and bruchid resistance in a germplasm survey of 105 resistant and susceptible genotypes and compared this with LD in other parts of the genome. Microsatellite allele diversity was found to vary with each of the eight APA-linked markers analyzed, and two markers within the APA locus were found to be diagnostic for bruchid resistance or susceptibility and for the different arcelin alleles inherited from the wild accessions. Arc1 was found to provide higher levels of resistance than Arc5 and the markers in the APA locus were highly associated with resistance showing that introgression of this gene-family from wild beans provides resistance in cultivated beans. LD around the APA locus was found to be intermediate compared to other regions of the genome and the highest LD was found within the APA locus itself for example between the markers PV-atct001 and PV-ag004. We found the APA locus to be an important genetic determinant of bruchid resistance and also found that LD existed mostly within the APA locus but not beyond it. Moderate LD was also found for some other regions of the genome perhaps related to domestication genes. The LD pattern may reflect the introgression of arcelin from the wild into the cultivated background through breeding. LD and association studies for

  15. Linkage disequilibrium at the APA insecticidal seed protein locus of common bean (Phaseolus vulgaris L.

    Directory of Open Access Journals (Sweden)

    Buendía Héctor F

    2010-04-01

    Full Text Available Abstract Background An interesting seed protein family with a role in preventing insect herbivory is the multi-gene, APA family encoding the α-amylase inhibitor, phytohemagglutinin and arcelin proteins of common bean (Phaseolus vulgaris. Variability for this gene family exists and has been exploited to breed for insect resistance. For example, the arcelin locus has been successfully transferred from wild to cultivated common bean genotypes to provide resistance against the bruchid species Zabrotes subfasciatus although the process has been hampered by a lack of genetic tools for and understanding about the locus. In this study, we analyzed linkage disequilibrium (LD between microsatellite markers at the APA locus and bruchid resistance in a germplasm survey of 105 resistant and susceptible genotypes and compared this with LD in other parts of the genome. Results Microsatellite allele diversity was found to vary with each of the eight APA-linked markers analyzed, and two markers within the APA locus were found to be diagnostic for bruchid resistance or susceptibility and for the different arcelin alleles inherited from the wild accessions. Arc1 was found to provide higher levels of resistance than Arc5 and the markers in the APA locus were highly associated with resistance showing that introgression of this gene-family from wild beans provides resistance in cultivated beans. LD around the APA locus was found to be intermediate compared to other regions of the genome and the highest LD was found within the APA locus itself for example between the markers PV-atct001 and PV-ag004. Conclusions We found the APA locus to be an important genetic determinant of bruchid resistance and also found that LD existed mostly within the APA locus but not beyond it. Moderate LD was also found for some other regions of the genome perhaps related to domestication genes. The LD pattern may reflect the introgression of arcelin from the wild into the cultivated

  16. Relationships between Locus of Control, Self-Efficacy, Efforts and Academic Achievement among Engineering Students

    Directory of Open Access Journals (Sweden)

    Alias Maizam

    2016-01-01

    Full Text Available The aim of this study is to investigate the relationships between the affective learning needs namely, self-efficacy and locus of control, learning efforts and academic achievement among engineering students. For this purpose, a survey was conducted on first year engineering students from two technical universities in Malaysia. Self-efficacy and locus of control were assessed using existing instruments while learning efforts were assessed using a specifically designed instrument based on Carbonaro’s model of learning effort. Academic achievement data were based on cumulative grade point average (CGPA obtained from self-report by participants. The findings indicate that females engineering students tend to have higher self-efficacy compared to males while both groups have similar locus of control and invest in similar learning efforts. Only locus of control is found to be related to academic achievement while self-efficacy is found to be related to efforts. In conclusion, locus of control seems to be an important factor in predicting academic achievement among engineering students.

  17. Analysis of meiotic segregation, using single-sperm typing: Meiotic drive at the myotonic dystrophy locus

    Energy Technology Data Exchange (ETDEWEB)

    Leeflang, E.P.; Arnheim, N. [Univ. of Southern California, Los Angeles, CA (United States); McPeek, M.S. [Univ. of Chicago, IL (United States)

    1996-10-01

    Meiotic drive at the myotonic dystrophy (DM) locus has recently been suggested as being responsible for maintaining the frequency, in the human population, of DM chromosomes capable of expansion to the disease state. In order to test this hypothesis, we have studied samples of single sperm from three individuals heterozygous at the DM locus, each with one allele larger and one allele smaller than 19 CTG repeats. To guard against the possible problem of differential PCR amplification rates based on the lengths of the alleles, the sperm were also typed at another closely linked marker whose allele size was unrelated to the allele size at the DM locus. Using statistical models specifically designed to study single-sperm segregation data, we find no evidence of meiotic segregation distortion. The upper limit of the two-sided 95% confidence interval for the estimate of the common segregation probability for the three donors is at or below .515 for all models considered, and no statistically significant difference from .5 is detected in any of the models. This suggests that any greater amount of segregation distortion at the myotonic dystrophy locus must result from events following sperm ejaculation. The mathematical models developed make it possible to study segregation distortion with high resolution by using sperm-typing data from any locus. 26 refs., 1 fig., 8 tabs.

  18. The IgH locus 3' regulatory region: pulling the strings from behind.

    Science.gov (United States)

    Pinaud, Eric; Marquet, Marie; Fiancette, Rémi; Péron, Sophie; Vincent-Fabert, Christelle; Denizot, Yves; Cogné, Michel

    2011-01-01

    Antigen receptor gene loci are among the most complex in mammals. The IgH locus, encoding the immunoglobulin heavy chain (IgH) in B-lineage cells, undergoes major transcription-dependent DNA remodeling events, namely V(D)J recombination, Ig class-switch recombination (CSR), and somatic hypermutation (SHM). Various cis-regulatory elements (encompassing promoters, enhancers, and chromatin insulators) recruit multiple nuclear factors in order to ensure IgH locus regulation by tightly orchestrated physical and/or functional interactions. Among major IgH cis-acting regions, the large 3' regulatory region (3'RR) located at the 3' boundary of the locus includes several enhancers and harbors an intriguing quasi-palindromic structure. In this review, we report progress insights made over the past decade in order to describe in more details the structure and functions of IgH 3'RRs in mouse and human. Generation of multiple cellular, transgenic and knock-out models helped out to decipher the function of the IgH 3' regulatory elements in the context of normal and pathologic B cells. Beside its interest in physiology, the challenge of elucidating the locus-wide cross talk between distant cis-regulatory elements might provide useful insights into the mechanisms that mediate oncogene deregulation after chromosomal translocations onto the IgH locus.

  19. Humour and the locus of control in The Gruffalo (Julia Donaldson & Axel Scheffler

    Directory of Open Access Journals (Sweden)

    B. van der Westhuizen

    2007-07-01

    Full Text Available The purpose of this article is firstly to distinguish between the notions “external locus of control” and “internal locus of control”, secondly to indicate ways in which the locus of control in humour in “The Gruffalo” by Julia Donaldson and Axel Scheffler can be identified and thirdly to indicate possible ways in which emphasis on the internal locus of control in the young reader can assist him/her in the development of a general mental/- psychological well-being. Different kinds of literary humour contribute to the ways in which young listeners/readers can identify with stories, poems, dramas and films. The young listener/reader can recognise him/herself in humorous situations, in the humorous use of imagery, wordplay and illustrations/visuals. He/she can also identify with or distance him-/herself from or reject the characters, the values represented and the author who created the text. When in interaction with the works of authors who use negative as well as positive kinds of humour to point out the dos and don’ts, the rights and the wrongs in life, the horizon of a young listener’s/reader’s experience can be expanded. Such a reading would contribute to the development of the young reader’s cognitive, emotional, social and moral values as it links up with an unconscious or conscious decision about the locus of control in his/her life.

  20. Genetic architecture and evolution of the S locus supergene in Primula vulgaris.

    Science.gov (United States)

    Li, Jinhong; Cocker, Jonathan M; Wright, Jonathan; Webster, Margaret A; McMullan, Mark; Dyer, Sarah; Swarbreck, David; Caccamo, Mario; Oosterhout, Cock van; Gilmartin, Philip M

    2016-12-02

    Darwin's studies on heterostyly in Primula described two floral morphs, pin and thrum, with reciprocal anther and stigma heights that promote insect-mediated cross-pollination. This key innovation evolved independently in several angiosperm families. Subsequent studies on heterostyly in Primula contributed to the foundation of modern genetic theory and the neo-Darwinian synthesis. The established genetic model for Primula heterostyly involves a diallelic S locus comprising several genes, with rare recombination events that result in self-fertile homostyle flowers with anthers and stigma at the same height. Here we reveal the S locus supergene as a tightly linked cluster of thrum-specific genes that are absent in pins. We show that thrums are hemizygous not heterozygous for the S locus, which suggests that homostyles do not arise by recombination between S locus haplotypes as previously proposed. Duplication of a floral homeotic gene 51.7 million years (Myr) ago, followed by its neofunctionalization, created the current S locus assemblage which led to floral heteromorphy in Primula. Our findings provide new insights into the structure, function and evolution of this archetypal supergene.

  1. Comparing Locus of Control, Assertiveness and General Health among Young Drug Addicts in Iran

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    Shahriar Shahidi

    2009-04-01

    Full Text Available "n "nObjective:The aim of this research was to compare the characteristics of assertiveness, locus of control and general health among young drug dependent patients in Iran. "n "nMethods: Three groups of Iranians: were choosed. The first group included drug dependent patients who had volunteered for treatment and had registered in the local Welfare Organization; the second group included dependent patients who were in the prison; and the third group held nondependent patients. All the participants were male and were matched for age and educational level . The following instruments were used in the present study: locus of control  uestionnaire , Assertiveness Scale and the General Health Questionnaire, GHQ. "n "nResults: The results of the present research showed that there were significant differences among the three groups in ssertiveness, locus of control and GHQ scores. It was found that participants in the non addictive group were more assertive and more internal in their locus of control and had higher GHQ scores than the other two groups. The participants in the prison group reported less assertiveness and lower GHQ scores than the non addictive group ; and their locus of control was more external. Conclusion: "n The results this study may be useful in terms of possible strategies for changing an attributive style in young adults in the framework of psychotherapy

  2. How does a protein reach its binding locus: sliding along DNA chain or not?

    CERN Document Server

    Li, Jingwei

    2016-01-01

    In gene expression, various kinds of proteins need to bind to specific locus of DNA. It is still not clear how these proteins find their target locus. In this study, the mean first-passage time (FPT) of protein binding to its target locus on DNA chain is discussed by a chain-space coupled model. Our results show that the 1-dimensional diffusion constant has a critical value, with which the mean time spent by a protein to find its target locus is almost independent of the binding rate of protein to DNA chain and the detachment rate from DNA chain. Which implies that, the frequency of protein binding to DNA and the sliding time on DNA chain have little influence on the search efficiency, and therefore whether or not the 1-dimensional sliding on DNA chain increases the search efficiency depends on the 1-dimensional diffusion constant of the protein on DNA chain. This study also finds that only protein bindings to DNA loci which are close to the target locus help to increase the search efficiency, while bindings ...

  3. Composición del locus de control en dos ciudades latinoamericanas

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    Jesús Francisco Laborín Álvarez

    2008-01-01

    Full Text Available El locus de control es un rasgo de personalidad vinculado con la atribución que hacen los individuos acerca de sus éxitos y fracasos. Los estudios en diferentes naciones y sociedades han demostrado que existen características generales y particulares respecto a la percepción de control y donde la cultura juega un papel importante. Se partió del objetivo de conocer la composición factorial del locus de control en dos poblaciones, Hermosillo, Sonora (México (n=600 y João Pessoa, Paraíba (Brasil (n=600; y establecer las diferencias en cuanto a dicho constructo en ambas poblaciones con respecto a las variables atributivas: edad, escolaridad, ocupación y ciudad. Los resultados revelan tres dimensiones comunes a las dos poblaciones: locus de control interno, locus de control afiliativo y locus de control externo. Los datos en general hacen ver que las muestras poblacionales de las ciudades hacen juicios de control en relación a los esfuerzos y el trabajo personal, en la afiliación a colectivos y grupos de interés como los fundamentos de explicación para éxitos y fracasos.

  4. Analysis of the 3' Cmu region of the rabbit Ig heavy chain locus.

    Science.gov (United States)

    Lanning, Dennis K; Zhai, Shi-Kang; Knight, Katherine L

    2003-05-08

    The immunoglobulin D (IgD) antibody class was, for many years, identified only in primates, rodents and teleost fish. The limited distribution of IgD among vertebrates suggested that IgD is a functionally redundant antibody class that has been lost by many vertebrate species during evolution. The recent identification of IgD in artiodactyls, however, suggests that IgD might be more widely expressed among vertebrates than previously thought, possibly serving a unique role in immunity. IgD expression has been searched for but not detected in rabbits. In order to search directly for a rabbit Cdelta locus encoding the constant region of IgD, we determined the nucleotide sequence of 13.5 kb of genomic DNA downstream of the rabbit Cmu locus. We did not find a rabbit Cdelta locus in this region, but found instead that this region is densely populated by repetitive elements, including a long interspersed DNA element repeat, six C repeats, and two processed pseudogenes. We conclude that the rabbit probably does not express IgD because there is no Cdelta locus immediately downstream of the rabbit Cmu locus.

  5. Multi-locus association study of schizophrenia susceptibility genes with a posterior probability method

    Institute of Scientific and Technical Information of China (English)

    SUN Xiangqing; JIA Yanbin; ZHANG Xuegong; XU Qi; SHEN Yan; LI Yanda

    2005-01-01

    Schizophrenia is a serious neuropsychiatric illness affecting about 1% of the world's population. It is considered a complex inheritance disorder. A number of genes are involved in combination in the etiology of the disorder. Evidence implicates the altered dopaminergic transmission in schizophrenia. In the present study, in order to identify susceptibility genes for schizophrenia in dopaminergic metabolism, we analyzed 59 single nucleotide polymorphisms (SNPs) in 24 genes of the dopaminergic pathway among 82 unrelated patients with schizophrenia and 108 matched normal controls. Considering that traditional single-locus association studies ignore the multigenic nature of complex diseases and do not take into account possible interactions between susceptibility genes, we proposed a multi-locus analysis method, using the posterior probability of morbidity as a measure of absolute disease risk for a multi-locus genotype combination, and developed an algorithm based on perturbation and average to detect the susceptibility multi-locus genotype combinations, as well as to repress noise and avoid false positive results at our best. A three-locus SNP genotype combination involved in the interactions of COMTand ALDH3B1 genes was detected to be significantly susceptible to schizophrenia.

  6. The relationship between the locus of control and thinking styles of teacher candidates

    Directory of Open Access Journals (Sweden)

    Gülşah Başol

    2009-04-01

    Full Text Available The purpose of the current study was to explore the relationship between the thinking styles and locus of control situations of university students. In addition, the differences in students' academic achievement levels according to their thinking styles and locus of control were searched. Differences in thinking styles and locus of control levels were also sought according to some study variables such as age, gender, parents' education level, the place most of the lifetime spent, and economical status.A descriptive correlational research design was applied in this research. The sample of the study was 131 teacher candidates, enrolled in Gaziosmanpaşa University in 2006-2007 education years in Tokat, Turkey. It was tried to reach all teacher candidates enrolled in the department, therefore no sampling approach was taken. In this study, Locus of Control Scale, developed by Rotter (1966 and adapted to Turkish by Dağ (1991 and Thinking Styles Inventory, developed by Sternberg and Wagner (1991, adapted to Turkish by Sünbül (2004 were utilized. Locus of control scale is designed to measure to assess a person's internal and external locus of control. The higher the scores in the scale, the locus of control is external. On the other hand, the thinking styles inventory measures a person's level of use of 13 thinking styles as legislative, executive, judicial, monarchic, hierarchic, oligarchic, anarchic, global, local, internal, external, liberal and conservative thinking style.In order to analyze the data, one way MONOVA, Pearson Product Correlation Coefficient, independent group t-test and ANOVA were used.The results are provided in two parts. In the first part, the results for the correlations among the locus of control and thinking styles were provided. The findings were summarized under three headings in the second part. First, it was searched whether there were differences when the dependent variables (locus of control and thinking styles used

  7. The relationship between the locus of control and thinking styles of teacher candidates

    Directory of Open Access Journals (Sweden)

    Gülşah Başol

    2009-04-01

    Full Text Available The purpose of the current study was to explore the relationship between the thinking styles and locus of control situations of university students. In addition, the differences in students' academic achievement levels according to their thinking styles and locus of control were searched.  Differences in thinking styles and locus of control levels were also sought according to some study variables such as age, gender, parents' education level, the place most of the lifetime spent, and economical status.A descriptive correlational research design was applied in this research. The sample of the study was 131 teacher candidates, enrolled in Gaziosmanpaşa University in 2006-2007 education years in Tokat, Turkey. It was tried to reach all teacher candidates enrolled in the department, therefore no sampling approach was taken. In this study, Locus of Control Scale, developed by Rotter (1966 and adapted to Turkish by Dağ (1991 and Thinking Styles Inventory, developed by Sternberg and Wagner (1991, adapted to Turkish by Sünbül (2004 were utilized. Locus of control scale is designed to measure to assess a person's internal and external locus of control. The higher the scores in the scale, the locus of control is external. On the other hand, the thinking styles inventory measures a person's level of use of 13 thinking styles as legislative, executive, judicial, monarchic, hierarchic, oligarchic, anarchic, global, local, internal, external, liberal and conservative thinking style.In order to analyze the data, one way MONOVA, Pearson Product Correlation Coefficient, independent group t-test and ANOVA were used. The results are provided in two parts. In the first part, the results for the correlations among the locus of control and thinking styles were provided. The findings were summarized under three headings in the second part. First, it was searched whether there were differences when the dependent variables (locus of control and thinking styles

  8. Effect of individualized goal-setting on college biology students' locus of control

    Science.gov (United States)

    Schafer, John E.

    This study investigated the effect of Individualized Goal-Setting A-T, relative to Classic A-T, on a student's locus of control (generalized and academic). This study also examined the effect of pretesting, relative to no pretesting, on a student's locus of control. Sixty students in an introductory, Audio-Tutorial, college zoology course were randomly assigned to treatment and control groups. Control groups (Classic A-T) completed the course in the usual manner. Treatment groups (IGS A-T) completed the course in the usual manner with one exception. That is, they used a different format for Optional Minicourse mastery. This new format released greater control to students over means as well as ends of minicourse mastery. Data were collected through use of the Solomon Four-Group design, with two levels of treatment (Classic A-T, IGS A-T) and two levels of pretesting (pretest, no pretest). Instruments included the Rotter I-E and Schafer Academic I-E Locus of Control Scales. Posttest scores were analyzed by a 2 × 2 multivariate analysis of variance (MANOVA).The following conclusions were made (p < 0.10).1IGS A-T, relative to Classic A-T, has no significant effect on a student's locus of control.2Pretesting, relative to no pretesting, has no significant effect on posttest locus of control.

  9. Hybrid male sterility in rice is due to epistatic interactions with a pollen killer locus.

    Science.gov (United States)

    Kubo, Takahiko; Yoshimura, Atsushi; Kurata, Nori

    2011-11-01

    In intraspecific crosses between cultivated rice (Oryza sativa) subspecies indica and japonica, the hybrid male sterility gene S24 causes the selective abortion of male gametes carrying the japonica allele (S24-j) via an allelic interaction in the heterozygous hybrids. In this study, we first examined whether male sterility is due solely to the single locus S24. An analysis of near-isogenic lines (NIL-F(1)) showed different phenotypes for S24 in different genetic backgrounds. The S24 heterozygote with the japonica genetic background showed male semisterility, but no sterility was found in heterozygotes with the indica background. This result indicates that S24 is regulated epistatically. A QTL analysis of a BC(2)F(1) population revealed a novel sterility locus that interacts with S24 and is found on rice chromosome 2. The locus was named Epistatic Factor for S24 (EFS). Further genetic analyses revealed that S24 causes male sterility when in combination with the homozygous japonica EFS allele (efs-j). The results suggest that efs-j is a recessive sporophytic allele, while the indica allele (EFS-i) can dominantly counteract the pollen sterility caused by S24 heterozygosity. In summary, our results demonstrate that an additional epistatic locus is an essential element in the hybrid sterility caused by allelic interaction at a single locus in rice. This finding provides a significant contribution to our understanding of the complex molecular mechanisms underlying hybrid sterility and microsporogenesis.

  10. Chronically ill patients’ expectations of therapeutic education and their health locus of control

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    Małgorzata Anna Basińska

    2015-12-01

    Full Text Available Background Beliefs as cognitive components of personality indicate what we consider as true or false and help us to answer questions concerning others, the world surrounding us and situations that we encounter. Beliefs about the health locus of control and their relations with expectations pertaining to therapeutic education seem to be of vital importance in the case of occurrence of a chronic illness. The aim of this paper is to verify whether expectations concerning therapeutic education in chronically ill patients demonstrate a relation with beliefs about the health locus of control and whether they vary according to gender, age and health, and to present the results of research that applies the Polish OE-15 scale for the evaluation of therapeutic education expectations depending on the health condition. Participants and procedure Two hundred and ninety-one persons were examined, including 180 patients and 111 healthy controls (the control group, 187 women and 104 men. The average age of subjects was 45.71 (SD = 13.51 years, ranging from 21 to 80 years. The OE-15 Therapeutic Education Expectations Scale and the Multidimensional Health Locus of Control Scale in versions relevant for patients and healthy controls as well as demographics were used. Results Age, gender and beliefs about the health locus of control are related to expectations of therapeutic education. Conclusions When providing therapeutic education for chronically ill patients, one should assess their expectations and pay attention to patients’ beliefs about the health locus of control.

  11. RefSeq and LocusLink: NCBI gene-centered resources.

    Science.gov (United States)

    Pruitt, K D; Maglott, D R

    2001-01-01

    Thousands of genes have been painstakingly identified and characterized a few genes at a time. Many thousands more are being predicted by large scale cDNA and genomic sequencing projects, with levels of evidence ranging from supporting mRNA sequence and comparative genomics to computing ab initio models. This, coupled with the burgeoning scientific literature, makes it critical to have a comprehensive directory for genes and reference sequences for key genomes. The NCBI provides two resources, LocusLink and RefSeq, to meet these needs. LocusLink organizes information around genes to generate a central hub for accessing gene-specific information for fruit fly, human, mouse, rat and zebrafish. RefSeq provides reference sequence standards for genomes, transcripts and proteins; human, mouse and rat mRNA RefSeqs, and their corresponding proteins, are discussed here. Together, RefSeq and LocusLink provide a non-redundant view of genes and other loci to support research on genes and gene families, variation, gene expression and genome annotation. Additional information about LocusLink and RefSeq is available at http://www.ncbi.nlm.nih.gov/LocusLink/.

  12. Change in the locus of dynamic loading axis on the knee joint after high tibial osteotomy.

    Science.gov (United States)

    Kawakami, Hideo; Sugano, Nobuhiko; Yonenobu, Kazuo; Yoshikawa, Hideki; Ochi, Takahiro; Nakata, Ken; Toritsuka, Yukiyoshi; Hattori, Asaki; Suzuki, Naoki

    2005-04-01

    The purpose of this study was to visualise the locus of the dynamic loading axis on the knee joint, and to evaluate changes in this locus during gait after high tibial osteotomy (HTO) in three patients who underwent HTO for medial compartment osteoarthritis (OA) of a varus knee. The bone structure of the lower limb and the relative position of skin markers were acquired from CT images. Motion capture data was acquired using spherical skin markers. Skeletal model movement during gait was calculated based on the movement of the markers. The locus of the dynamic loading axis on the knee joint was defined as the point on the proximal tibia joint surface that intersected with the loading axis of the lower limb, which passed through the centre of the femoral head and the centroid of multiple points surrounded by the distal tibia joint surface contour. This system was able to visualise the locus of the dynamic loading axis on the knee joint and not only lateral but also anterior-posterior direction movement. After HTO, the locus shifted from a medial and posterior area of the medial joint edge of the knee to a central area of the knee joint surface. This indicates that HTO shifted the dynamic loading axis. Lateral movement of the dynamic loading axis in the early stance phase of gait was reduced within a year after HTO.

  13. Dominant cataract mutations and specific-locus mutations in mice induced by radiation or ethylnitrosourea

    Energy Technology Data Exchange (ETDEWEB)

    Ehling, U.H.; Favor, J.; Kratochvilova, J.; Neuhaeuser-Klaus, A. (Gesellschaft fuer Strahlen- und Umweltforschung m.b.H. Muenchen, Neuherberg (Germany, F.R.). Inst. fuer Genetik)

    1982-01-01

    In a combined experiment, dominant cataract mutations and specific-locus mutations were scored in the same offspring. In radiation experiments, a total of 15 dominant cataract and 38 specific-locus mutations was scored in 29396 offspring. In experiments with ethylnitrosourea (ENU), a total of 12 dominant cataracts and 54 specific-locus mutations was observed in 12712 offspring. The control frequency for dominant cataracts was 0 in 9954 offspring and for specific-locus mutations 11 in 169955 offspring. The two characteristic features of radiation-induced specific-locus mutations - the augmenting effect of dose fractionation and the quantitative differences in the mutation rates between spermatogonial and post-spermatogonial stages - can also be demonstrated for the induction of dominant cataracts. The dominant cataract mutations recovered can be categorized into 7 phenotypic classes. The only noteworthy difference observed between the radiation- and ENU-induced mutations recovered was that, of the 2 radiation-induced total lens opacities, both were associated with an iris anomaly and microphthalmia whereas the ENU-induced total opacities were not.

  14. [Validation of a sport injury locus of control scale].

    Science.gov (United States)

    Paquet, Y

    2008-04-01

    In the area of health psychology, locus of control (LOC) [Psychol Monogr 80 (1966) 1-28] has consistently been considered as a dimension of personality which may entail many potential benefits for the individual. Originally, the LOC by Rotter [Psychol Monogr 80 (1966) 1-28] is a unidimensional concept. He defines: on one hand individuals with an internal LOC who establish a link between their behavior and the reinforcement obtained, and on the other hand, individuals with an external LOC who do not establish any link between their behavior and the reinforcement obtained. However, since Rotter, other authors like Levenson [Distinctions within the concept of internal-external control: development of a new scale. In: Proceedings of the 80th annual convention of the American psychological association. 1972. p. 261-2] have claimed a multidimensional concept with three factors: the internal (I), powerful other (P), and chance (C). The MHLCS was constructed with three factors, according to Levenson's model. Numerous scales have been designed in order to assess health-related LOC. The most widely used is the MHLCS [Health Educ Monogr 6 (1978) 160-170]. According to Lecocq [La réhabilitation après la blessure. In: Manuel de psychologie du sport : l'intervention auprès du sportif. Paris: Revue EPS; 2003. p. 377-402], such a multidimensional view would allow in-depth examinations of sport injuries. Indeed, from a theoretical perspective, sport participants with high LOC ratings are assumed to suffer less frequent injuries than those scoring low on this dimension. The purpose of the present paper is to present an adapted version of the MHLCS in French language. For Bruchon-Schweitzer [Bruchon-Schweitzer M, Dantzer R. Introduction à la psychologie de la santé. Paris: Presses universitaires de France; 1994], the three factors (I, P, and C) are independent or a little intercorrelated. Therefore, two models of sport injury LOC scale have been studied: the first with three

  15. An acid phosphatase locus expressed in mouse kidney (Apk) and its genetic location on chromosome 10.

    Science.gov (United States)

    Womack, J E; Auerbach, S B

    1978-04-01

    A genetic locus controlling the electrophoretic mobility of an acid phosphatase in mouse kidney is described. This locus, called acid phosphatase-kidney (Apk), is not expressed in erythrocytes, liver, spleen, heart, lung, brain, skeletal muscle, stomach, or testes. The product of Apk hydrolyzes the substrate naphthol AS-MX phosphoric acid but is not active on alpha-naphthylphosphate or 4-methylumbelliferylphosphate. It is not inactivated by 50 C for 1 hr, nor is its electrophoretic mobility altered by incubation with neuraminidase. The locus is invariant among 31 inbred strains (Apka), with a variant allele (Apkm) observed only in Mus musculus molossinus. Codominant expression was observed in F1 hybrids of M. m. molossinus and inbred strains. Apk was mapped on Chr 10, near the neurological mutant waltzer (v).

  16. Pure Land or Pure Mind?: Locus of Awakening and American Popular Religious Culture

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    Richard K. Payne

    2015-03-01

    Full Text Available This essay has two sections, each with its own distinct goal, forming an interrelated whole. The first introduces “locus of awakening,” and applies it to the relative success in America of Zen and Tibetan Buddhisms, compared to Pure Land Buddhism. The explanatory power of the concept is demonstrated by also considering Soka Gakkai. The difference between popular culture treatments of Zen and Tibetan Buddhisms, and Pure Land Buddhism was the problematic leading to identifying locus of awakening as an aspect of Buddhist thought. The second section locates it in the history of Buddhist thought, demonstrating that it is not a modern conceptualization of the path, not one created in response to Euro–American religio-therapeutic culture. Locus of awakening is, instead, part of the continuity of the Buddhist tradition, and does not fall on one side or the other of the sometimes overdrawn dichotomy between Asian and American Buddhisms.

  17. A Second Stellar Color Locus: a Bridge from White Dwarfs to M stars

    CERN Document Server

    Smolcic, V; Knapp, G R; Lupton, R H; Pavlovski, K; Ilijic, S; Schlegel, D J; Smith, J A; McGehee, P M; Silvestri, N M; Hawley, S L; Rockosi, C M; Gunn, J E; Strauss, M A; Fan, X; Eisenstein, D J; Harris, H

    2004-01-01

    We report the discovery of a locus of stars in the SDSS g-r vs. u-g color-color diagram that connects the colors of white dwarfs and M dwarfs. While its contrast with respect to the main stellar locus is only ~1:2300, this previously unrecognized feature includes 863 stars from the SDSS Data Release 1. The position and shape of the feature are in good agreement with predictions of a simple binary star model that consists of a white dwarf and an M dwarf, with the components' luminosity ratio controlling the position along this binary system locus. SDSS DR1 spectra for 47 of these objects strongly support this model. The absolute magnitude--color distribution inferred for the white dwarf component is in good agreement with the models of Bergeron et al. (1995).

  18. Emotional Intelligence and OCB: The Moderating Role of Work Locus of Control.

    Science.gov (United States)

    Turnipseed, David L

    2017-07-10

    This study sought to identify linkages between Mayer, Salovey, and Caruso's (2008) four dimensions of emotional intelligence (EI) and organizational citizenship behavior, and the moderating influence of locus of control. Using a sample of 290 employed students, the present study examines the effects of the dimensions of EI on OCB directed at individuals (OCB-I) and OCB directed at the organization (OCB-O). Emotionally intelligent individuals were hypothesized to engage in more organizational citizenship behavior (OCB) than individuals with lower EI. Work locus of control was hypothesized to moderate the emotional intelligence-OCB linkage, with high internals having a stronger emotional intelligence to OCB linkage. Results indicate that the EI dimensions of perceiving, understanding, and managing emotions had positive effects on OCB-I and OCB-O. Using emotions was not linked to OCB. Locus of control strengthened the EI to OCB-I link, but had no effect on the OCB-O linkage.

  19. The Limits of the Use of Locus of Control in Industrial Psychology: A Critical Evaluation

    Directory of Open Access Journals (Sweden)

    Emir Üzümçeker

    2016-10-01

    Full Text Available Locus of control is a personality variable that is employed by researchers from diverse disciplines. This article examines the limits of the construct’s usage in industrial and organizational psychology. Although locus of control is documented to predict a wide array of workplace behavior such as job satisfaction, job performance and turnover intention, some important conceptual, methodological and empirical flaws raise suspicions on the explanations proposed by researchers. Considering the shortage of experimental and longitudinal evidence, it is argued that the causal direction of the well-established correlations between locus of control and other organizational behavioral variables might be the opposite of the theory’s expectation. It is also claimed that some related constructs such as self-efficacy and belief in a just world might provide further explanations for observed correlations.

  20. Mexican-American mothers' socialization strategies: effects of education, acculturation, and health locus of control.

    Science.gov (United States)

    Cousins, J H; Power, T G; Olvera-Ezzell, N

    1993-04-01

    The present study examined maternal education, acculturation, and health locus of control beliefs in relation to parenting strategies that promote the internalization of healthy eating habits in Mexican-American children. Eighty low-income Mexican-American mothers and their 4- to 8-year-old children participated in the study. Mother-child interactions during dinner were observed, and mothers were interviewed about the socialization strategies they used to influence their children's food consumption. Results indicated that mothers with more external health locus of control beliefs were less likely to use socialization techniques associated with internalization. Acculturation was negatively related to the use of internalization techniques, with less traditional mothers using more directive strategies. Education did not predict maternal behavior after controlling for health locus of control beliefs.

  1. A polychromatic ‘greenbeard' locus determines patterns of cooperation in a social amoeba

    Science.gov (United States)

    Gruenheit, Nicole; Parkinson, Katie; Stewart, Balint; Howie, Jennifer A.; Wolf, Jason B.; Thompson, Christopher R. L.

    2017-01-01

    Cheaters disrupt cooperation by reaping the benefits without paying their fair share of associated costs. Cheater impact can be diminished if cooperators display a tag (‘greenbeard') and recognise and preferentially direct cooperation towards other tag carriers. Despite its popular appeal, the feasibility of such greenbeards has been questioned because the complex patterns of partner-specific cooperative behaviours seen in nature require greenbeards to come in different colours. Here we show that a locus (‘Tgr') of a social amoeba represents a polychromatic greenbeard. Patterns of natural Tgr locus sequence polymorphisms predict partner-specific patterns of cooperation by underlying variation in partner-specific protein–protein binding strength and recognition specificity. Finally, Tgr locus polymorphisms increase fitness because they help avoid potential costs of cooperating with incompatible partners. These results suggest that a polychromatic greenbeard can provide a key mechanism for the evolutionary maintenance of cooperation. PMID:28120827

  2. The sae locus of Staphylococcus aureus encodes a two-component regulatory system.

    Science.gov (United States)

    Giraudo, A T; Calzolari, A; Cataldi, A A; Bogni, C; Nagel, R

    1999-08-01

    Sae is a regulatory locus that activates the production of several exoproteins in Staphylococcus aureus. A 3.4-kb fragment of a S. aureus genomic library, screened with a probe adjacent to the transposon insertion of a sae::Tn551 mutant, was cloned into a bifunctional vector. This fragment was shown to carry the sae locus by restoration of exoprotein production in sae mutants. The sae locus was mapped to the SmaI-D fragment of the staphylococcal chromosome by pulse-field electrophoresis. Sequence analysis of the cloned fragment revealed the presence of two genes, designated saeR and saeS, encoding a response regulator and a histidine protein kinase, respectively, with high homology to other bacterial two-component regulatory systems.

  3. [A nurse's experience applying Rotter's locus of control theory in a myocardial infarction patient].

    Science.gov (United States)

    Shi, Meng-Ling; Ke, Ya-Ting

    2009-04-01

    This case report shares the experience of one nurse in applying Rotter's locus of control theory in her care of a myocardial infarction patient. Period of care ran from November 23 to December 1, 2007. The author collected subjective and objective data through observations and interviews with the patient in the ward. Data was analyzed to identify key healthcare problems. These included the inadequate information of the patient on his condition, which negatively influenced health behavior; inadequate health information available; and the flare-up of disease symptoms. Internal locus of control, as presented in Rotter's locus of control theory, was applied to the above nursing problems in order to deliver individualized nursing care to the patient based on mutual trust. Such enhanced patient disease cognition, facilitated his obtaining health information, helped him adjust to disease symptom episodes, and promoted his adjustment to the disease and adoption of more healthy behavior.

  4. Analysis of Single Locus Trajectories for Extracting In Vivo Chromatin Tethering Interactions.

    Directory of Open Access Journals (Sweden)

    Assaf Amitai

    2015-08-01

    Full Text Available Is it possible to extract tethering forces applied on chromatin from the statistics of a single locus trajectories imaged in vivo? Chromatin fragments interact with many partners such as the nuclear membrane, other chromosomes or nuclear bodies, but the resulting forces cannot be directly measured in vivo. However, they impact chromatin dynamics and should be reflected in particular in the motion of a single locus. We present here a method based on polymer models and statistics of single trajectories to extract the force characteristics and in particular when they are generated by the gradient of a quadratic potential well. Using numerical simulations of a Rouse polymer and live cell imaging of the MAT-locus located on the yeast Saccharomyces cerevisiae chromosome III, we recover the amplitude and the distance between the observed and the interacting monomer. To conclude, the confined trajectories we observed in vivo reflect local interaction on chromatin.

  5. DNA polymorphism at locus-2 of growth hormone gene of Madura cattle

    Directory of Open Access Journals (Sweden)

    NITA ETIKAWATI

    2003-01-01

    Full Text Available The objectives of the research were to detect DNA polymorphism at locus 2 of bovine growth hormone gene of Madura cattle and to know its genetic diversity. DNA polymorphisms and their effect on phenotypic traits have been studied widely in dairy cattle but not for beef cattle, especially for Indonesian local cattle. Polymorphism was detected using PCR-RFLP using primer GH-5 and GH-6 for amplifying locus 2 of growth hormone gene. Genetic diversity was analyzed based on the formula of Nei (1973, 1975. DNA polymorphism was found on locus 2 of growth hormone gene using MspI restriction enzyme. This polymorphism may be caused the lost of restriction MspI site. The genetic diversity was 0.4422.

  6. Modifications of Hodge bundles and enumerative geometry : the stable hyperelliptic locus. Part 1: semicompact type

    CERN Document Server

    Ran, Ziv

    2010-01-01

    We compute, in terms of tautological classes, the fundamental class of the locus of stable hyperelliptic curves, i.e. the closure in the moduli space of stable curves of the locus of smooth hyperelliptic curves. The computation is based on the technique of intersection theory on Hilbert schemes (of degree 2 in this case) associated to families of nodal curves. We describe a certain bundle map ('degree-2 Brill-Noether') whose degeneracy locus consists of the stable hyperelliptics plus a residual scheme, whose contribution we compute using Fulton-MacPherson excess intersection theory. Part 1 focuses on curves of semi-compact type, whose dual graph contains cycles of length at most 2.

  7. Molecular Characterization Of The Vernalization Locus VRN1 In Perennial Ryegrass

    DEFF Research Database (Denmark)

    Asp, Torben; Byrne, Stephen; Andersen, Jeppe R;

    Vernalization, the requirement of a period of low temperature to induce transition from vegetative to reproductive state, is an important trait in grasses. The objective of this study was to identify the causative polymorphism(s) for the variation in vernalization requirement at the VRN1 locus in...... in perennial ryegrass (Lolium perenne). Two allelic BAC clones of the VRN1 locus from the two genotypes Veyo and Falster with contrasting vernalization requirements were identified, sequenced, and characterized. The region surrounding the VRN1 locus in perennial ryegrass showed micro......-colinearity to the corresponding region on chromosome 3 in Oryza sativa with conserved gene order and orientation, while the micro-colinearity to the corresponding region in Triticum monococcum was less conserved. Repeat elements constituted 42 and 58% of the Veyo and Falster BAC sequences, respectively, of which the majority...

  8. An unusual occurrence of repeated single allele variation on Y-STR locus DYS458

    Directory of Open Access Journals (Sweden)

    Pankaj Shrivastava

    2016-09-01

    Full Text Available Six brothers were accused of gagging and raping a woman. A single male Y-STR profile was obtained from vaginal smear swab and clothes of the victim, which did not match with the DNA profile of the accused brothers. As a reference point, the blood sample of their father (aged 87 years was also analyzed with the same kit. The Y-STR haplotype of all six brothers was found to be the same as that of their father except at locus DYS458. At this locus, while the eldest, second and fourth siblings share allele 18 with their father, a loss of one repeat (allele 17 instead of 18 is observed in the third son while fifth and sixth siblings have allele 19 representing a gain of one repeat. Thus, two changes viz. a gain (twice and loss of one repeat at this locus in one generation is both interesting and unusual.

  9. A locus problem solved by using a mechanism with three dyads and two leading elements

    Science.gov (United States)

    Popescu, I.; Sass, L.; Romanescu, A. E.

    2016-11-01

    In Geometry there are many types of loci, solved by means of classic geometrical considerations and yielding lines and arcs of circles or conics. Yet more complicated locus can be solved by means of the Theory of Mechanisms. Our research starts from a locus and provides a solution based on the Theory of Mechanisms, finding the equivalent mechanism. The structural and cinematic analysis of the mechanism is made, determining the trajectory of a point representing the locus which presents interest. The mechanism has three dyads and two leading elements, for which the movements were correlated by means of a coefficient q. For various values of q different loci were obtained, similar for close values of q but different for significantly different values of q.

  10. Confirmation of locus heterogeneity in the pure form of familial spastic paraplegia

    Energy Technology Data Exchange (ETDEWEB)

    Speer, M.C.; Gaskell, P.C.; Robinson, L.C. [Duke Univ. Medical Center, Durham, NC (United States)] [and others

    1995-08-14

    Familial spastic paraplegia (FSP), characterized by progressive spasticity of the lower extremities, is in its {open_quotes}pure{close_quotes} form generally of autosomal dominant inheritance pattern. Hazen et al. reported tight linkage of a large FSP family to the highly polymorphic microsatellite marker D14S269 with z ({sub {theta}}) = 8.49 at {sub {theta}} = 0.00. They further demonstrated evidence for locus heterogeneity when they showed that 2 FSP families were unlinked to this region. We have subsequently studied 4 FSP families (3 American, one British) and excluded the disease locus in these families for approximately 30 cM on either side of D14S269, thereby confirming evidence for locus heterogeneity within the spastic paraplegia diagnostic classification. 28 refs., 2 figs., 4 tabs.

  11. A polychromatic 'greenbeard' locus determines patterns of cooperation in a social amoeba.

    Science.gov (United States)

    Gruenheit, Nicole; Parkinson, Katie; Stewart, Balint; Howie, Jennifer A; Wolf, Jason B; Thompson, Christopher R L

    2017-01-25

    Cheaters disrupt cooperation by reaping the benefits without paying their fair share of associated costs. Cheater impact can be diminished if cooperators display a tag ('greenbeard') and recognise and preferentially direct cooperation towards other tag carriers. Despite its popular appeal, the feasibility of such greenbeards has been questioned because the complex patterns of partner-specific cooperative behaviours seen in nature require greenbeards to come in different colours. Here we show that a locus ('Tgr') of a social amoeba represents a polychromatic greenbeard. Patterns of natural Tgr locus sequence polymorphisms predict partner-specific patterns of cooperation by underlying variation in partner-specific protein-protein binding strength and recognition specificity. Finally, Tgr locus polymorphisms increase fitness because they help avoid potential costs of cooperating with incompatible partners. These results suggest that a polychromatic greenbeard can provide a key mechanism for the evolutionary maintenance of cooperation.

  12. Jurors' locus of control and defendants' attractiveness in death penalty sentencing.

    Science.gov (United States)

    Beckham, Crystal M; Spray, Beverly J; Pietz, Christina A

    2007-06-01

    The authors examined the relationship between jurors' locus of control and defendants' attractiveness in death penalty sentencing. Ninety-eight participants voluntarily served as mock jurors. The authors administered J. B. Rotter's (1966) Internal-External Locus of Control Scale to participants and then randomly assigned them to a group with either an attractive or an unattractive defendant (represented by photographs). Participants read a murder vignette and selected a punishment--either a lifetime jail sentence or the death penalty-for the defendant. Results indicated that neither jurors' locus of control nor defendants' attractiveness influenced sentencing. However, jurors' age and gender significantly influenced sentencing. Men, with the exception of the youngest men, were more likely than women to choose the death penalty. Additionally, young women were more likely than older women to select the death penalty. The authors discuss the implications of these results for the study of jury behavior and bias.

  13. The Finnish lapphund retinal atrophy locus maps to the centromeric region of CFA9

    Directory of Open Access Journals (Sweden)

    Sargan David R

    2007-07-01

    Full Text Available Abstract Background Dogs have the second largest number of genetic diseases, after humans. Among the diseases present in dogs, progressive retinal atrophy has been reported in more than a hundred breeds. In some of them, the mutation has been identified and genetic tests have allowed the identification of carriers, thus enabling a drastic reduction in the incidence of the disease. The Finnish lapphund is a dog breed presenting late-onset progressive retinal atrophy for which the disease locus remains unknown. Results In this study we mapped the progressive retinal atrophy locus in the Finnish lapphund using a DNA pooling approach, assuming that all affected dogs within the breed share the same identical-by descent-mutation as the cause of the disease (genetic homogeneity. Autosomal recessive inheritance was also assumed, after ruling out, from pedigree analysis, dominant and X-linked inheritance. DNA from 12 Finnish lapphund cases was mixed in one pool, and DNA from 12 first-degree relatives of these cases was mixed to serve as the control pool. The 2 pools were tested with 133 microsatellite markers, 3 of which showed a shift towards homozygosity in the cases. Individual genotyping with these 3 markers confirmed homozygosity for the GALK1 microsatellite only (chromosome 9. Further individual genotyping with additional samples (4 cases and 59 controls confirmed the association between this marker and the disease locus (p Conclusion The locus for progressive rod-cone degeneration is known to be close to the GALK1 locus, on the telomeric region of chromosome 9, where the retinal atrophy locus of the Finnish lapphund has been mapped. This suggests that the disease in this breed, as well as in the Swedish lapphund, may correspond to progressive rod-cone degeneration. This would increase the number of known dog breeds having this particular form of progressive retinal atrophy.

  14. Single locus affects embryonic segment polarity and multiple aspects of an adult evolutionary novelty

    Directory of Open Access Journals (Sweden)

    Saenko Suzanne V

    2010-08-01

    Full Text Available Abstract Background The characterization of the molecular changes that underlie the origin and diversification of morphological novelties is a key challenge in evolutionary developmental biology. The evolution of such traits is thought to rely largely on co-option of a toolkit of conserved developmental genes that typically perform multiple functions. Mutations that affect both a universal developmental process and the formation of a novelty might shed light onto the genetics of traits not represented in model systems. Here we describe three pleiotropic mutations with large effects on a novel trait, butterfly eyespots, and on a conserved stage of embryogenesis, segment polarity. Results We show that three mutations affecting eyespot size and/or colour composition in Bicyclus anynana butterflies occurred in the same locus, and that two of them are embryonic recessive lethal. Using surgical manipulations and analysis of gene expression patterns in developing wings, we demonstrate that the effects on eyespot morphology are due to changes in the epidermal response component of eyespot induction. Our analysis of morphology and of gene expression in mutant embryos shows that they have a typical segment polarity phenotype, consistent with the mutant locus encoding a negative regulator of Wingless signalling. Conclusions This study characterizes the segregation and developmental effects of alleles at a single locus that controls the morphology of a lineage-specific trait (butterfly eyespots and a conserved process (embryonic segment polarity and, specifically, the regulation of Wingless signalling. Because no gene with such function was found in the orthologous, highly syntenic genomic regions of two other lepidopterans, we hypothesize that our locus is a yet undescribed, possibly lineage-specific, negative regulator of the conserved Wnt/Wg pathway. Moreover, the fact that this locus interferes with multiple aspects of eyespot morphology and maps to a

  15. Evolutionary conservation of CCND1-ORAOV1-FGF19-FGF4 locus from zebrafish to human.

    Science.gov (United States)

    Katoh, Masuko; Katoh, Masaru

    2003-07-01

    The CCND1-ORAOV1-FGF19-FGF4-FGF3-FLJ10261-FADD-PPFIA1-EMS1 locus on human chromosome 11q13 is frequently amplified in esophageal cancer, breast cancer, and bladder tumors. FGF19, FGF4 and FGF3 genes are implicated in embryogenesis and carcinogenesis. We proposed in 2002 the hypothesis that mouse Fgf15 might be the ortholog of human FGF19 based on comparative genomics. Here, we identified zebrafish fgf19 and oraov1 genes by using bioinformatics to demonstrate the hypothesis. Zebrafish fgf19 gene, consisting of three exons, was located around nucleotide position 121802-124963 of zebrafish genome draft sequence AL929586.12 in the reverse orientation. Zebrafish fgf19 (209 aa) was more homologous to chicken fgf19 and human FGF19 than to rodent Fgf15. Zebrafish oraov1 gene, consisting of five exons, was located around nucleotide position 112172-115838 of AL929586.12 in the reverse orientation. Zebrafish oraov1 protein (141 aa) was more homologous to human ORAOV1 than to rodent Oraov1. The CCND1-ORAOV1-FGF19-FGF4 locus was well conserved between human and zebrafish genomes in the order of genes, in the direction of genes, and in the exon-intron structure. Rat Ccnd1-Oraov1-Fgf15-Fgf4 locus was synthenic to mouse Ccnd1-Oraov1 (also known as 2210010N10Rik)-Fgf15-Fgf4 locus. Fgf15, homologous to human FGF19 and zebrafish fgf19, was located on the synthenic locus of human FGF19 and zebrafish fgf19 within rodent genomes. Based on the evolutionary conservation of the CCND1-ORAOV1-FGF19-FGF4 locus from zebrafish to human, it was concluded that Fgf15 gene is the rodent ortholog of human FGF19 gene.

  16. Locus of Control and Career Interest of Sophomore Accountancy Students: Basis for Employment Path

    Directory of Open Access Journals (Sweden)

    Jovielyn Mañibo

    2014-02-01

    Full Text Available This academic undertaking sought to determine the relationship between the locus of control and career interest of the respondents towards their future employment. The objectives of the study were to determine the respondents’ locus of control and career interest; to find if there is a significant relationship between the respondents’ locus of control and career interest and to develop an action plan that will gauge the students’ employment success as to their chosen field. In measuring and finding the relationship between the variables of the study, the researchers employed the quantitative method in the analysis of data using the questionnaires for locus of control (LOC and Career Cluster Interest Survey (CCIS as dominant tools. The participants chosen from this study were 74sophomore Accountancy students for Second Semester, School Year 2012 – 2013. Based from the results, most of the respondents (74 sophomore accountancy students have an external locus of control with career interest on education and training, human services, and finance. The computed rvalues indicates slight positive correlation, however, careers on government services, manufacturing , public administration, health science, human services showed significant correlation to internal (positive and external (negative locus of control. .Likewise, the Counseling and Testing Center of the university should conduct cognitive training targeting reasoning and speed of processing that can improve sense of personal control over one’s life and facilitate career orientation during the student- applicants’ admission as regards to their National Career Assessment Examination (NCAE results. With the findings of the study, a program design was created to gauge students employment path.

  17. Self-statements, locus of control, and depression in predicting self-esteem.

    Science.gov (United States)

    Philpot, V D; Holliman, W B; Madonna, S

    1995-06-01

    The contributions of frequency of positive and negative self-statements and their ratio, locus of control, and depression in prediction of self-esteem were examined. Volunteers were 145 college students (100 women and 45 men) who were administered the Coopersmith Self-esteem Inventory-Adult Form, Automatic Thought Questionnaire-Revised, the Beck Depression Inventory, and the Rotter Internal-External Locus of Control Scale. Intercorrelations suggested significant relationships among variables. The magnitude of the relationship was strongest between the frequency of negative self-statements and self-esteem. These results are consistent with and lend further support to prior studies of Kendall, et al. and Schwartz and Michaelson.

  18. Social Work Professionals’ Emotional Intelligence, Locus Of Control And Role Efficacy: An Exploratory Study

    Directory of Open Access Journals (Sweden)

    Sanjay K. Singh

    2006-11-01

    Full Text Available The principal objective of the study was to study social work professionals psychologically. This study was conducted on a sample of 178 participants. The findings depict role efficacy to be associated positively with emotional intelligence and internal locus of control, but negatively with external locus of control. Similarly, emotional intelligence was found to be associated positively with internality, but negatively related to externality. The findings also indicated that emotional intelligence alone accounts for 43% of the variance on role efficacy of social work professionals. The findings of the study have major implications for non-governmental organizations and are discussed.

  19. Nonlinkage of D6S260, a putative schizophrenia locus, to bipolar affective disorder

    Energy Technology Data Exchange (ETDEWEB)

    Adams, L.J.; Mitchell, P.B. [Univ. of South Wales (Australia); Salmon, J. [Garvan Institute of Medical Research, Sydney, New South Wales (Australia)] [and others

    1996-09-20

    To examine whether genes that predispose to schizophrenia also confer a predisposition to other psychiatric disorders such as bipolar affective disorder (BAD), we tested for linkage between the recently identified schizophrenia susceptibility locus D6S260 and the inheritance of BAD in 12 large Australian pedigrees. We found no evidence for linkage over a region of 12-27 cM from the D6S260 locus, depending on the model used. Our results therefore do not provide support for the continuum theory of psychosis. 13 refs., 2 tabs.

  20. Analysis of non-typeable Haemophilus influenzae in invasive disease reveals lack of the capsule locus.

    Science.gov (United States)

    Lâm, T-T; Claus, H; Frosch, M; Vogel, U

    2016-01-01

    Among invasive Haemophilus influenzae, unencapsulated strains have largely surpassed the previously predominant serotype b (Hib) because of Hib vaccination. Isolates without the genomic capsule (cap) locus are designated non-typeable H. influenzae (NTHi). They are different from capsule-deficient variants that show deletion of the capsule transport gene bexA within the cap locus. The frequency of capsule-deficient variants in invasive disease is unknown. We analysed 783 unencapsulated invasive isolates collected over 5 years in Germany and found no single capsule-deficient isolate. Invasive unencapsulated strains in Germany were exclusively NTHi. A negative serotyping result by slide agglutination was therefore highly predictive for NTHi.

  1. Diferencias individuales y desarrollo de habilidades de liderazgo : el rol del locus de control

    OpenAIRE

    García Hernández, Jorge Alejandro; Guarin Galvis, Stephany

    2015-01-01

    El presente proyecto se ha elaborado con la finalidad de encontrar la relación existente entre el liderazgo y el locus de control, por medio de una revisión documental que permita dar una visión más amplia de estos dos fenómenos. De acuerdo con investigaciones realizadas, existen características individuales que afectan el desarrollo de liderazgo, lo cual a su vez tiene un impacto sobre el comportamiento de los individuos dentro de una sociedad. Uno de estos factores es el locus de contro...

  2. Composición del locus de control en dos ciudades latinoamericanas

    OpenAIRE

    Jesús Francisco Laborín Álvarez; José Ángel Vera Noriega; Francisco Fernando Durazo Salas; Erik Misael Parra Armenta

    2008-01-01

    El locus de control es un rasgo de personalidad vinculado con la atribución que hacen los individuos acerca de sus éxitos y fracasos. Los estudios en diferentes naciones y sociedades han demostrado que existen características generales y particulares respecto a la percepción de control y donde la cultura juega un papel importante. Se partió del objetivo de conocer la composición factorial del locus de control en dos poblaciones, Hermosillo, Sonora (México) (n=600) y João Pessoa, Paraíba (Bras...

  3. DNA marker mining of ILSTS035 microsatellite locus on chromosome 6 of Hanwoo cattle

    Indian Academy of Sciences (India)

    Jung-Sou Yeo; Jea-Young Lee; Jae-Woo Kim

    2004-12-01

    We describe tests for detecting and locating quantitative trait loci (QTL) for traits in Hanwoo cattle. From results of a permutation test to detect QTL for marbling, we selected the microsatellite locus ILSTS035 on chromosome 6 for further analysis. -means clustering analysis applied to five traits and nine DNA markers in ILSTS035 resulted in three cluster groups. Finally we employed the bootstrap test method to calculate confidence intervals using the resampling method to find major DNA markers. We conclude that the major markers of ILSTS035 locus on chromosome 6 of Hanwoo cattle are markers 235 bp and 266 bp.

  4. The Application of Eddy Current Transducer for Testing Movement Locus of Shaker Screen

    Institute of Scientific and Technical Information of China (English)

    Zhu Pingyu; Lao Chuanjun; Zhang Wei; Li Xuejun

    2007-01-01

    Shaker screen is one of important equipments in the industry of oil, metallurgy, coal and timbering. The movement locus of shaker screen affects the capacity and efficiency of shaker screen to split the solid particle from crude ore directly .To test movement of shaker locus, two eddy current transducers are employed. A discussion of the usage of these eddy current transducer to test and acceleration sensors will be made. The experiment results from a real elliptic shaker screen have good agree with the design requirements.

  5. Fv-1 locus restriction of mouse retroviruses in glucocorticoid-treated cells

    Energy Technology Data Exchange (ETDEWEB)

    Tennant, R.W.; Jones, S.C.; Otten, J.A.; Yang, W.K.; Brown, A.

    1978-08-01

    Treatment of mouse embryo cells with hydrocortisone (10/sup -6/M) or dexamethasone (10/sup -4/ to 10/sup -6/M) increases virus synthesis whether the cells are permissive or restrictive at the Fv-1 locus. However, the number of cells infected was not increased in either permissive or restrictive cells by treatment with either glucocorticoid, and the two-hit titration pattern in restrictive cells remained unaltered. Therefore, the enhancement of virus replication by the glucocorticoids is independent of Fv-1 restriction and appears to occur after the Fv-1 locus-sensitive step in virus synthesis.

  6. Updated listing of haplotypes at the human phenylalanine hydroxylase (PAH) locus

    Energy Technology Data Exchange (ETDEWEB)

    Eisensmith, R.C.; Woo, S.L.C. (Baylor College of Medicine, Houston, TX (United States))

    1992-12-01

    Analysis of mutant PAH chromosomes has identified approximately 60 different single-base substitutions and deletions within the PAH locus. Nearly all of these molecular lesions are in strong linkage disequilibrium with specific RFLP haplotypes in different ethnic populations. Thus, haplotype analysis is not only useful for diagnostic purposes but is proving to be a valuable tool in population genetic studies of the origin and spread of phenylketonuria alleles in human populations. PCR-based methods have been developed to detect six of the eight polymorphic restriction sites used for determination of RFLP haplotypes at the PAH locus. A table of the proposed expanded haplotypes is given.

  7. Linkage disequilibrium between incompatibility locus region genes in the plant Arabidopsis lyrata

    DEFF Research Database (Denmark)

    Hagenblad, Jenny; Bechsgaard, Jesper Smærup; Charlesworth, Deborah

    2006-01-01

    , and the ortholog in A. lyrata (a self-incompatible species) is in the homologous genome region and is known as Aly8. It is thus of interest to test whether Aly8 sequence diversity is elevated due to close linkage to the highly polymorphic incompatibility locus, as is theoretically predicted. However, Aly8...... to the incompatibility locus, one being a pseudogene. We determined the phase of multiple haplotypes in families of plants from Icelandic and other populations. Different Aly8 sequence types are associated with different SRK alleles, while haplotypes with the same SRK sequences tend to have the same Aly8 sequence...

  8. The Effects of Internal-External Locus of Control and Selected Demographic Variables on Rational-Irrational Beliefs.

    Science.gov (United States)

    Martin, Janice E.; And Others

    This study evaluated whether or not locus of control mediates rational-irrational beliefs. Data were generated investigating the impact of an internal-external orientation and selected demographic variables (age, race, gender, education, and occupation) on rational-irrational beliefs. Independent variables were locus of control and demographic…

  9. Evidence that breast cancer risk at the 2q35 locus is mediated through IGFBP5 regulation

    NARCIS (Netherlands)

    M. Ghoussaini (Maya); S.L. Edwards (Stacey); K. Michailidou (Kyriaki); S. Nord (Silje); R. Cowper-Sal-lari (Richard); K. Desai (Kinjal); S. Kar (Siddhartha); K.M. Hillman (Kristine); S. Kaufmann (Susanne); D.M. Glubb (Dylan); J. Beesley (Jonathan); J. Dennis (Joe); M.K. Bolla (Manjeet); Q. Wang (Qing); E. Dicks (Ed); Q. Guo (Qi); M.K. Schmidt (Marjanka); M. Shah (Mitul); R.N. Luben (Robert); J. Brown (Judith); K. Czene (Kamila); H. Darabi (Hatef); M. Eriksson (Mats); D. Klevebring (Daniel); S.E. Bojesen (Stig); B.G. Nordestgaard (Børge); S.F. Nielsen (Sune); H. Flyger (Henrik); D. Lambrechts (Diether); B. Thienpont (Bernard); P. Neven (Patrick); H. Wildiers (Hans); A. Broeks (Annegien); L.J. van 't Veer (Laura); E.J.T. Rutgers (Emiel); F.J. Couch (Fergus); J.E. Olson (Janet); B. Hallberg (Boubou); C. Vachon (Celine); J. Chang-Claude (Jenny); A. Rudolph (Anja); P. Seibold (Petra); D. Flesch-Janys (Dieter); J. Peto (Julian); I. dos Santos Silva (Isabel); L.J. Gibson (Lorna); H. Nevanlinna (Heli); T.A. Muranen (Taru); K. Aittomäki (Kristiina); C. Blomqvist (Carl); P. Hall (Per); J. Li (Jingmei); J. Liu (Jianjun); M.K. Humphreys (Manjeet); D. Kang (Daehee); J.-Y. Choi (J.); S.K. Park (Sue); D-Y. Noh (Dong-Young); K. Matsuo (Keitaro); H. Ito (Hidemi); H. Iwata (Hisato); Y. Yatabe (Yasushi); P. Guénel (Pascal); T. Truong (Thérèse); F. Menegaux (Florence); M. Sanchez (Marie); B. Burwinkel (Barbara); F. Marme (Federick); A. Schneeweiss (Andreas); C. Sohn (Christof); A.H. Wu (Anna H.); C.-C. Tseng (Chiu-Chen); D. Van Den Berg (David); D.O. Stram (Daniel O.); J. Benítez (Javier); M.P. Zamora (Pilar); J.I.A. Perez (Jose Ignacio Arias); P. Menéndez (Primitiva); X.-O. Shu (Xiao-Ou); W. Lu (Wei); Y. Gao; Q. Cai (Qiuyin); A. Cox (Angela); S.S. Cross (Simon); M.W.R. Reed (Malcolm); I.L. Andrulis (Irene); J.A. Knight (Julia); G. Glendon (Gord); S. Tchatchou (Sandrine); E.J. Sawyer (Elinor); I.P. Tomlinson (Ian); M. Kerin (Michael); N. Miller (Nicola); C.A. Haiman (Christopher); B.E. Henderson (Brian); F.R. Schumacher (Fredrick); L. Le Marchand (Loic); A. Lindblom (Annika); S. Margolin (Sara); S.-H. Teo; C.H. Yip (Cheng Har); D.S.C. Lee (Daphne S.C.); T.Y. Wong (Tien Y.); M.J. Hooning (Maartje); J.W.M. Martens (John W. M.); J.M. Collee (Margriet); C.H.M. van Deurzen (Carolien); J.L. Hopper (John); M.C. Southey (Melissa); H. Tsimiklis (Helen); M.K. Kapuscinski (Miroslav K.); C-Y. Shen (Chen-Yang); P.-E. Wu (Pei-Ei); J-C. Yu (Jyh-Cherng); S.-T. Chen; G.G. Alnæs (Grethe Grenaker); A.-L. Borresen-Dale (Anne-Lise); G.G. Giles (Graham); R.L. Milne (Roger); C.A. McLean (Catriona Ann); K.R. Muir (K.); A. Lophatananon (Artitaya); S. Stewart-Brown (Sarah); P. Siriwanarangsan (Pornthep); M. Hartman (Mikael); X. Miao; S.A.B.S. Buhari (Shaik Ahmad Bin Syed); Y.Y. Teo (Yik Ying); P.A. Fasching (Peter); L. Haeberle (Lothar); A.B. Ekici (Arif); M.W. Beckmann (Matthias); H. Brenner (Hermann); A.K. Dieffenbach (Aida Karina); V. Arndt (Volker); C. Stegmaier (Christa); A.J. Swerdlow (Anthony ); A. Ashworth (Alan); N. Orr (Nick); M. Schoemaker (Minouk); M. García-Closas (Montserrat); J.D. Figueroa (Jonine); S.J. Chanock (Stephen); J. Lissowska (Jolanta); J. Simard (Jacques); M.S. Goldberg (Mark); F. Labrèche (France); M. Dumont (Martine); R. Winqvist (Robert); K. Pykäs (Katri); A. Jukkola-Vuorinen (Arja); H. Brauch (Hiltrud); T. Brüning (Thomas); Y.-D. Koto (Yon-Dschun); P. Radice (Paolo); P. Peterlongo (Paolo); B. Bonnani (Bernardo); S. Volorio (Sara); T. Dörk (Thilo); N.V. Bogdanova (Natalia); S. Helbig (Sonja); A. Mannermaa (Arto); V. Kataja (Vesa); V-M. Kosma (Veli-Matti); J.M. Hartikainen (J.); P. Devilee (Peter); R.A.E.M. Tollenaar (Rob); C.M. Seynaeve (Caroline); C.J. van Asperen (Christi); A. Jakubowska (Anna); J. Lubinski (Jan); K. Jaworska-Bieniek (Katarzyna); K. Durda (Katarzyna); S. Slager (Susan); A.E. Toland (Amanda); C.B. Ambrosone (Christine); D. Yannoukakos (Drakoulis); S. Sangrajrang (Suleeporn); V. Gaborieau (Valerie); P. Brennan (Paul); J.D. McKay (James); U. Hamann (Ute); D. Torres (Diana); W. Zheng (Wei); J. Long (Jirong); H. Anton-Culver (Hoda); S.L. Neuhausen (Susan); C. Luccarini (Craig); C. Baynes (Caroline); S. Ahmed (Shahana); M. Maranian (Melanie); S. Healey (Sue); A. González-Neira (Anna); G. Pita (G.); M.R. Alonso (M Rosario); N. Álvarez (Nuria); D. Herrero (Daniel); D.C. Tessier (Daniel C.); D. Vincent (Daniel); F. Bacot (Francois); I. de Santiago (Ines); J. Carroll (Jason); C. Caldas (Carlos); M. Brown (Melissa); M. Lupien (Mathieu); V. Kristensen (Vessela); P.D.P. Pharoah (Paul); G. Chenevix-Trench (Georgia); J.D. French (Juliet); D.F. Easton (Douglas); A.M. Dunning (Alison); P. Webb (Penny); A. De Fazio (Anna)

    2014-01-01

    textabstractGWAS have identified a breast cancer susceptibility locus on 2q35. Here we report the fine mapping of this locus using data from 101,943 subjects from 50 case-control studies. We genotype 276 SNPs using the 'iCOGS' genotyping array and impute genotypes for a further 1,284 using 1000 Geno

  10. Evidence that breast cancer risk at the 2q35 locus is mediated through IGFBP5 regulation

    DEFF Research Database (Denmark)

    Ghoussaini, Maya; Edwards, Stacey L; Michailidou, Kyriaki

    2014-01-01

    GWAS have identified a breast cancer susceptibility locus on 2q35. Here we report the fine mapping of this locus using data from 101,943 subjects from 50 case-control studies. We genotype 276 SNPs using the 'iCOGS' genotyping array and impute genotypes for a further 1,284 using 1000 Genomes Proje...

  11. Integration of least angle regression with empirical Bayes for multi-locus genome-wide association studies

    Science.gov (United States)

    Multi-locus genome-wide association studies has become the state-of-the-art procedure to identify quantitative trait loci (QTL) associated with traits simultaneously. However, implementation of multi-locus model is still difficult. In this study, we integrated least angle regression with empirical B...

  12. Academic Locus of Control, Tendencies Towards Academic Dishonesty and Test Anxiety Levels as the Predictors of Academic Self-Efficacy

    Science.gov (United States)

    Yesilyurt, Etem

    2014-01-01

    Many studies have focused on finding the level of effect that academic locus of control, tendencies towards academic dishonesty, and test anxiety levels have had on academic self-efficacy, and providing a separate explanation ratio for each. The relationship among the effects of the academic locus of control, tendencies towards academic…

  13. Characterization of mutations and sequence variants in the D21S11 locus by next generation sequencing

    DEFF Research Database (Denmark)

    Rockenbauer, Eszter; Hansen, Stine; Mikkelsen, Martin

    2014-01-01

    . In 18 of the confirmed trios, a genetic inconsistency was observed between one of the parents and the child at the D21S11 locus. NGS of the D21S11 locus revealed which allele had mutated from which parent to the child in 13 of these trios. All characterized mutations could be explained by single...

  14. Evaluation of two multi-locus sequence typing schemes for commensal Escherichia coli from dairy cattle in Washington State.

    Science.gov (United States)

    Ahmed, Sara; Besser, Thomas E; Call, Douglas R; Weissman, Scott J; Jones, Lisa P; Davis, Margaret A

    2016-05-01

    Multi-locus sequence typing (MLST) is a useful system for phylogenetic and epidemiological studies of multidrug-resistant Escherichiacoli. Most studies utilize a seven-locus MLST, but an alternate two-locus typing method (fumC and fimH; CH typing) has been proposed that may offer a similar degree of discrimination at lower cost. Herein, we compare CH typing to the standard seven-locus method for typing commensal E. coli isolates from dairy cattle. In addition, we evaluated alternative combinations of eight loci to identify combinations that maximize discrimination and congruence with standard seven-locus MLST among commensal E. coli while minimizing the cost. We also compared both methods when used for typing uropathogenic E. coli (UPEC). CH typing was less discriminatory for commensal E. coli than the standard seven-locus method (Simpson's Index of Diversity=0.933 [0.902-0.964] and 0.97 [0.96-0.979], respectively). Combining fimH with housekeeping gene loci improved discriminatory power for commensal E. coli from cattle but resulted in poor congruence with MLST. We found that a four-locus typing method including the housekeeping genes adk, purA, gyrB and recA could be used to minimize cost without sacrificing discriminatory power or congruence with Achtman seven-locus MLST when typing commensal E. coli.

  15. On Using of the Personal Computer as to Determining Root Locus of the Characteristic Equations in the Systems

    OpenAIRE

    藤塚, 幸一; 中川, 孝之

    1984-01-01

    We have studied the solutions of elemen tary problems on the control systems and the graphical method as to determining root locus of the characteristic equations by using the BASIC programs of digital computer.In this paper, we have described the results of BASIC programs of these methods and constructed the figures of root locus of these equations in the s-plane.

  16. Multiple independent variants at the TERT locus are associated with telomere length and risks of breast and ovarian cancer

    NARCIS (Netherlands)

    Bojesen, Stig E.; Pooley, Karen A.; Johnatty, Sharon E.; Beesley, Jonathan; Michailidou, Kyriaki; Tyrer, Jonathan P.; Edwards, Stacey L.; Pickett, Hilda A.; Shen, Howard C.; Smart, Chanel E.; Hillman, Kristine M.; Mai, Phuong L.; Lawrenson, Kate; Stutz, Michael D.; Lu, Yi; Karevan, Rod; Woods, Nicholas; Johnstonw, Rebecca L.; French, Juliet D.; Chen, Xiaoqing; Weischer, Maren; Nielsen, Sune F.; Maranian, Melanie J.; Ghoussaini, Maya; Ahmed, Shahana; Baynes, Caroline; Bolla, Manjeet K.; Wang, Qin; Dennis, Joe; McGuffog, Lesley; Barrowdale, Daniel; Lee, Andrew; Healey, Sue; Lush, Michael; Tessier, Daniel C.; Vincent, Daniel; Bacot, Francis; Vergote, Ignace; Lambrechts, Sandrina; Despierre, Evelyn; Risch, Harvey A.; Gonzalez-Neira, Anna; Rossing, Mary Anne; Pita, Guillermo; Doherty, Jennifer A.; Alvarez, Nuria; Larson, Melissa C.; Fridley, Brooke L.; Schoof, Nils; Chang-Claude, Jenny; Cicek, Mine S.; Peto, Julian; Kalli, Kimberly R.; Broeks, Annegien; Armasu, Sebastian M.; Schmidt, Marjanka K.; Braaf, Linde M.; Winterhoff, Boris; Nevanlinna, Heli; Konecny, Gottfried E.; Lambrechts, Diether; Rogmann, Lisa; Guenel, Pascal; Teoman, Attila; Milne, Roger L.; Garcia, Joaquin J.; Cox, Angela; Shridhar, Vijayalakshmi; Burwinkel, Barbara; Marme, Frederik; Hein, Rebecca; Sawyer, Elinor J.; Haiman, Christopher A.; Wang-Gohrke, Shan; Andrulis, Irene L.; Moysich, Kirsten B.; Hopper, John L.; Odunsi, Kunle; Lindblom, Annika; Giles, Graham G.; Brenner, Hermann; Simard, Jacques; Lurie, Galina; Fasching, Peter A.; Carney, Michael E.; Radice, Paolo; Wilkens, Lynne R.; Swerdlow, Anthony; Goodman, Marc T.; Brauch, Hiltrud; Garcia-Closas, Montserrat; Hillemanns, Peter; Winqvist, Robert; Durst, Matthias; Devilee, Peter; Runnebaum, Ingo; Jakubowska, Anna; Lubinski, Jan; Mannermaa, Arto; Butzow, Ralf; Bogdanova, Natalia V.; Doerk, Thilo; Pelttari, Liisa M.; Zheng, Wei; Leminen, Arto; Anton-Culver, Hoda; Bunker, Clareann H.; Kristensen, Vessela; Ness, Roberta B.; Muir, Kenneth; Edwards, Robert; Meindl, Alfons; Heitz, Florian; Matsuo, Keitaro; du Bois, Andreas; Wu, Anna H.; Harter, Philipp; Teo, Soo-Hwang; Schwaab, Ira; Shu, Xiao-Ou; Blot, William; Hosono, Satoyo; Kang, Daehee; Nakanishi, Toru; Hartman, Mikael; Yatabe, Yasushi; Hamann, Ute; Karlan, Beth Y.; Sangrajrang, Suleeporn; Kjaer, Susanne Kruger; Gaborieau, Valerie; Jensen, Allan; Eccles, Diana; Hogdall, Estrid; Shen, Chen-Yang; Brown, Judith; Woo, Yin Ling; Shah, Mitul; Azmi, Mat Adenan Noor; Luben, Robert; Omar, Siti Zawiah; Czene, Kamila; Vierkant, Robert A.; Nordestgaard, Borge G.; Flyger, Henrik; Vachon, Celine; Olson, Janet E.; Wang, Xianshu; Levine, Douglas A.; Rudolph, Anja; Weber, Rachel Palmieri; Flesch-Janys, Dieter; Iversen, Edwin; Nickels, Stefan; Schildkraut, Joellen M.; Silva, Isabel Dos Santos; Cramer, Daniel W.; Gibson, Lorna; Terry, Kathryn L.; Fletcher, Olivia; Vitonis, Allison F.; van der Schoot, C. Ellen; Poole, Elizabeth M.; Hogervorst, Frans B. L.; Tworoger, Shelley S.; Liu, Jianjun; Bandera, Elisa V.; Li, Jingmei; Olson, Sara H.; Humphreys, Keith; Row, Irene; Blomqvist, Carl; Rodriguez-Rodriguez, Lorna; Aittomaki, Kristiina; Salvesen, Helga B.; Muranen, Taru A.; Wik, Elisabeth; Brouwers, Barbara; Krakstad, Camilla; Wauters, Els; Halle, Mari K.; Wildiers, Hans; Kiemeney, Lambertus A.; Mulot, Claire; Aben, Katja K.; Laurent-Puig, Pierre; Altena, Anne Mvan; Therese Truong, [No Value; Massuger, Leon F. A. G.; Benitez, Javier; Pejovic, Tanja; Arias Perez, Jose Ignacio; Hoatlin, Maureen; Zamora, M. Pilar; Cook, Linda S.; Balasubramanian, Sabapathy P.; Kelemen, Linda E.; Schneeweiss, Andreas; Le, Nhu D.; Sohn, Christof; Brooks-Wilson, Angela; Tomlinson, Ian; Kerin, Michael J.; Miller, Nicola; Cybulski, Cezary; Henderson, Brian E.; Menkiszak, Janusz; Schumacher, Fredrick; Wentzensen, Nicolas; Marchand, Loic Le; Yang, Hannah P.; Mulligan, Anna Marie; Glendon, Gord; Engelholm, Svend Aage; Knight, Julia A.; Hogdall, Claus K.; Apicella, Carmel; Gore, Martin; Tsimiklis, Helen; Song, Honglin; Southey, Melissa C.; Jager, Agnes; den Ouweland, Ans M. Wvan; Brown, Robert; Martens, John W. M.; Flanagan, James M.; Kriege, Mieke; Paul, James; Margolin, Sara; Siddiqui, Nadeem; Severi, Gianluca; Whittemore, Alice S.; Baglietto, Laura; McGuire, Valerie; Stegmaier, Christa; Sieh, Weiva; Mueller, Heiko; Arndt, Volker; Labreche, France; Gao, Yu-Tang; Goldberg, Mark S.; Yang, Gong; Dumont, Martine; McLaughlin, John R.; Hartmann, Arndt; Ekici, Arif B.; Beckmann, Matthias W.; Phelan, Catherine M.; Lux, Michael P.; Permuth-Wey, Jenny; Peissel, Bernard; Sellers, Thomas A.; Ficarazzi, Filomena

    TERT-locus SNPs and leukocyte telomere measures are reportedly associated with risks of multiple cancers. Using the Illumina custom genotyping array iCOG, we analyzed similar to 480 SNPs at the TERT locus in breast (n = 103,991), ovarian (n = 39,774) and BRCA1 mutation carrier (n = 11,705) cancer

  17. 9q31.2-rs865686 as a susceptibility locus for estrogen receptor-positive breast cancer

    DEFF Research Database (Denmark)

    Warren, Helen; Dudbridge, Frank; Fletcher, Olivia

    2012-01-01

    Our recent genome-wide association study identified a novel breast cancer susceptibility locus at 9q31.2 (rs865686).......Our recent genome-wide association study identified a novel breast cancer susceptibility locus at 9q31.2 (rs865686)....

  18. Multiple independent variants at the TERT locus are associated with telomere length and risks of breast and ovarian cancer

    DEFF Research Database (Denmark)

    Bojesen, Stig Egil; Pooley, Karen A; Johnatty, Sharon E

    2013-01-01

    TERT-locus SNPs and leukocyte telomere measures are reportedly associated with risks of multiple cancers. Using the Illumina custom genotyping array iCOGs, we analyzed ∼480 SNPs at the TERT locus in breast (n = 103,991), ovarian (n = 39,774) and BRCA1 mutation carrier (n = 11,705) cancer cases an...

  19. Multiple independent variants at the TERT locus are associated with telomere length and risks of breast and ovarian cancer

    NARCIS (Netherlands)

    Bojesen, Stig E.; Pooley, Karen A.; Johnatty, Sharon E.; Beesley, Jonathan; Michailidou, Kyriaki; Tyrer, Jonathan P.; Edwards, Stacey L.; Pickett, Hilda A.; Shen, Howard C.; Smart, Chanel E.; Hillman, Kristine M.; Mai, Phuong L.; Lawrenson, Kate; Stutz, Michael D.; Lu, Yi; Karevan, Rod; Woods, Nicholas; Johnstonw, Rebecca L.; French, Juliet D.; Chen, Xiaoqing; Weischer, Maren; Nielsen, Sune F.; Maranian, Melanie J.; Ghoussaini, Maya; Ahmed, Shahana; Baynes, Caroline; Bolla, Manjeet K.; Wang, Qin; Dennis, Joe; McGuffog, Lesley; Barrowdale, Daniel; Lee, Andrew; Healey, Sue; Lush, Michael; Tessier, Daniel C.; Vincent, Daniel; Bacot, Francis; Vergote, Ignace; Lambrechts, Sandrina; Despierre, Evelyn; Risch, Harvey A.; Gonzalez-Neira, Anna; Rossing, Mary Anne; Pita, Guillermo; Doherty, Jennifer A.; Alvarez, Nuria; Larson, Melissa C.; Fridley, Brooke L.; Schoof, Nils; Chang-Claude, Jenny; Cicek, Mine S.; Peto, Julian; Kalli, Kimberly R.; Broeks, Annegien; Armasu, Sebastian M.; Schmidt, Marjanka K.; Braaf, Linde M.; Winterhoff, Boris; Nevanlinna, Heli; Konecny, Gottfried E.; Lambrechts, Diether; Rogmann, Lisa; Guenel, Pascal; Teoman, Attila; Milne, Roger L.; Garcia, Joaquin J.; Cox, Angela; Shridhar, Vijayalakshmi; Burwinkel, Barbara; Marme, Frederik; Hein, Rebecca; Sawyer, Elinor J.; Haiman, Christopher A.; Wang-Gohrke, Shan; Andrulis, Irene L.; Moysich, Kirsten B.; Hopper, John L.; Odunsi, Kunle; Lindblom, Annika; Giles, Graham G.; Brenner, Hermann; Simard, Jacques; Lurie, Galina; Fasching, Peter A.; Carney, Michael E.; Radice, Paolo; Wilkens, Lynne R.; Swerdlow, Anthony; Goodman, Marc T.; Brauch, Hiltrud; Garcia-Closas, Montserrat; Hillemanns, Peter; Winqvist, Robert; Durst, Matthias; Devilee, Peter; Runnebaum, Ingo; Jakubowska, Anna; Lubinski, Jan; Mannermaa, Arto; Butzow, Ralf; Bogdanova, Natalia V.; Doerk, Thilo; Pelttari, Liisa M.; Zheng, Wei; Leminen, Arto; Anton-Culver, Hoda; Bunker, Clareann H.; Kristensen, Vessela; Ness, Roberta B.; Muir, Kenneth; Edwards, Robert; Meindl, Alfons; Heitz, Florian; Matsuo, Keitaro; du Bois, Andreas; Wu, Anna H.; Harter, Philipp; Teo, Soo-Hwang; Schwaab, Ira; Shu, Xiao-Ou; Blot, William; Hosono, Satoyo; Kang, Daehee; Nakanishi, Toru; Hartman, Mikael; Yatabe, Yasushi; Hamann, Ute; Karlan, Beth Y.; Sangrajrang, Suleeporn; Kjaer, Susanne Kruger; Gaborieau, Valerie; Jensen, Allan; Eccles, Diana; Hogdall, Estrid; Shen, Chen-Yang; Brown, Judith; Woo, Yin Ling; Shah, Mitul; Azmi, Mat Adenan Noor; Luben, Robert; Omar, Siti Zawiah; Czene, Kamila; Vierkant, Robert A.; Nordestgaard, Borge G.; Flyger, Henrik; Vachon, Celine; Olson, Janet E.; Wang, Xianshu; Levine, Douglas A.; Rudolph, Anja; Weber, Rachel Palmieri; Flesch-Janys, Dieter; Iversen, Edwin; Nickels, Stefan; Schildkraut, Joellen M.; Silva, Isabel Dos Santos; Cramer, Daniel W.; Gibson, Lorna; Terry, Kathryn L.; Fletcher, Olivia; Vitonis, Allison F.; van der Schoot, C. Ellen; Poole, Elizabeth M.; Hogervorst, Frans B. L.; Tworoger, Shelley S.; Liu, Jianjun; Bandera, Elisa V.; Li, Jingmei; Olson, Sara H.; Humphreys, Keith; Row, Irene; Blomqvist, Carl; Rodriguez-Rodriguez, Lorna; Aittomaki, Kristiina; Salvesen, Helga B.; Muranen, Taru A.; Wik, Elisabeth; Brouwers, Barbara; Krakstad, Camilla; Wauters, Els; Halle, Mari K.; Wildiers, Hans; Kiemeney, Lambertus A.; Mulot, Claire; Aben, Katja K.; Laurent-Puig, Pierre; Altena, Anne Mvan; Therese Truong, [No Value; Massuger, Leon F. A. G.; Benitez, Javier; Pejovic, Tanja; Arias Perez, Jose Ignacio; Hoatlin, Maureen; Zamora, M. Pilar; Cook, Linda S.; Balasubramanian, Sabapathy P.; Kelemen, Linda E.; Schneeweiss, Andreas; Le, Nhu D.; Sohn, Christof; Brooks-Wilson, Angela; Tomlinson, Ian; Kerin, Michael J.; Miller, Nicola; Cybulski, Cezary; Henderson, Brian E.; Menkiszak, Janusz; Schumacher, Fredrick; Wentzensen, Nicolas; Marchand, Loic Le; Yang, Hannah P.; Mulligan, Anna Marie; Glendon, Gord; Engelholm, Svend Aage; Knight, Julia A.; Hogdall, Claus K.; Apicella, Carmel; Gore, Martin; Tsimiklis, Helen; Song, Honglin; Southey, Melissa C.; Jager, Agnes; den Ouweland, Ans M. Wvan; Brown, Robert; Martens, John W. M.; Flanagan, James M.; Kriege, Mieke; Paul, James; Margolin, Sara; Siddiqui, Nadeem; Severi, Gianluca; Whittemore, Alice S.; Baglietto, Laura; McGuire, Valerie; Stegmaier, Christa; Sieh, Weiva; Mueller, Heiko; Arndt, Volker; Labreche, France; Gao, Yu-Tang; Goldberg, Mark S.; Yang, Gong; Dumont, Martine; McLaughlin, John R.; Hartmann, Arndt; Ekici, Arif B.; Beckmann, Matthias W.; Phelan, Catherine M.; Lux, Michael P.; Permuth-Wey, Jenny; Peissel, Bernard; Sellers, Thomas A.; Ficarazzi, Filomena; Barile, Monica; Ziogas, Argyrios; Ashworth, Alan; Gentry-Maharaj, Aleksandra; Jones, Michael; Ramus, Susan J.; Orr, Nick; Menon, Usha; Pearce, Celeste L.; Bruening, Thomas; Pike, Malcolm C.; Ko, Yon-Dschun; Lissowska, Jolanta; Figueroa, Jonine; Kupryjanczyk, Jolanta; Chanock, Stephen J.; Dansonka-Mieszkowska, Agnieszka; Jukkola-Vuorinen, Arja; Rzepecka, Iwona K.; Pylkas, Katri; Bidzinski, Mariusz; Kauppila, Saila; Hollestelle, Antoinette; Seynaeve, Caroline; Tollenaar, Rob A. E. M.; Durda, Katarzyna; Jaworska, Katarzyna; Hartikainen, Jaana M.; Kosma, Veli-Matti; Kataja, Vesa; Antonenkova, Natalia N.; Long, Jirong; Shrubsole, Martha; Deming-Halverson, Sandra; Lophatananon, Artitaya; Siriwanarangsan, Pornthep; Stewart-Brown, Sarah; Ditsch, Nina; Lichtner, Peter; Schmutzler, Rita K.; Ito, Hidemi; Iwata, Hiroji; Tajima, Kazuo; Tseng, Chiu-Chen; Stram, Daniel O.; van den Berg, David; Yip, Cheng Har; Ikrarn, M. Kamran; Teh, Yew-Ching; Cai, Hui; Lu, Wei; Signorello, Lisa B.; Cai, Qiuyin; Noh, Dong-Young; Yoo, Keun-Young; Miao, Hui; Iau, Philip Tsau-Choong; Teo, Yik Ying; McKay, James; Shapiro, Charles; Ademuyiwa, Foluso; Fountzilas, George; Hsiung, Chia-Ni; Yu, Jyh-Cherng; Hou, Ming-Feng; Healey, Catherine S.; Luccarini, Craig; Peock, Susan; Stoppa-Lyonnet, Dominique; Peterlongo, Paolo; Rebbeck, Timothy R.; Piedmonte, Marion; Singer, Christian F.; Friedman, Eitan; Thomassen, Mads; Offit, Kenneth; Hansen, Thomas V. O.; Neuhausen, Susan L.; Szabo, Csilla I.; Blanco, Ignacio; Garber, Judy; Narod, Steven A.; Weitzel, Jeffrey N.; Montagna, Marco; Olah, Edith; Godwin, Andrew K.; Yannoukakos, Drakoulis; Goldgar, David E.; Caldes, Trinidad; Imyanitov, Evgeny N.; Tihomirova, Laima; Arun, Banu K.; Campbell, Ian; Mensenkamp, Arjen R.; van Asperen, Christi J.; van Roozendaa, Kees E. P.; Meijers-Heijboer, Hanne; Collee, J. Margriet; Oosterwijk, Jan C.; Hooning, Maartje J.; Rookus, Matti A.; van der Luijt, Rob B.; Os, Theo A. Mvan; Evans, D. Gareth; Frost, Debra; Fineberg, Elena; Barwell, Julian; Walker, Lisa; Kennedy, M. John; Platte, Radka; Davidson, Rosemarie; Ellis, Steve D.; Cole, Trevor; Bressac-de Paillerets, Brigitte; Buecher, Bruno; Damiola, Francesca; Faivre, Laurence; Frenay, Marc; Sinilnikova, Olga M.; Caron, Olivier; Giraud, Sophie; Mazoyer, Sylvie; Bonadona, Valerie; Caux-Moncoutier, Virginie; Toloczko-Grabarek, Aleksandra; Gronwald, Jacek; Byrski, Tomasz; Spurdle, Amanda B.; Bonanni, Bernardo; Zaffaroni, Daniela; Giannini, Giuseppe; Bernard, Loris; Dolcetti, Riccardo; Manoukian, Siranoush; Arnold, Norbert; Engel, Christoph; Deissler, Helmut; Rhiem, Kerstin; Niederacher, Dieter; Pendl, Hansjoerg; Sutter, Christian; Wappenschmidt, Barbara; Borg, Ake; Mein, Beatrice; Rantala, Johanna; Soller, Maria; Nathanson, Katherine L.; Domchek, Susan M.; Rodriguez, Gustavo C.; Salani, Ritu; Kaulich, Daphne Gschwantler; Tea, Muy-Kheng; Paluch, Shani Shimon; Laitman, Yael; Skytte, Anne-Bine; Kruse, Torben A.; Jensen, Uffe Birk; Robson, Mark; Gerdes, Anne-Marie; Ejlertsen, Bent; Foretova, Lenka; Savage, Sharon A.; Lesterm, Jenny; Soucy, Penny; Kuchenbaecker, Karoline B.; Olswold, Curtis; Cunningham, Julie M.; Slager, Susan; Pankratz, Vernon S.; Dicks, Ed; Lakhani, Sunil R.; Couch, Fergus J.; Hall, Per; Monteiro, Alvaro N. A.; Gayther, Simon A.; Pharoah, Paul D. P.; Reddel, Roger R.; Goode, Ellen L.; Greene, Mark H.; Easton, Douglas F.; Berchuck, Andrew; Antoniou, Antonis C.; Chenevix-Trench, Georgia; Dunning, Alison M.

    2013-01-01

    TERT-locus SNPs and leukocyte telomere measures are reportedly associated with risks of multiple cancers. Using the Illumina custom genotyping array iCOG, we analyzed similar to 480 SNPs at the TERT locus in breast (n = 103,991), ovarian (n = 39,774) and BRCA1 mutation carrier (n = 11,705) cancer ca

  20. Quantitative Linkage for Autism Spectrum Disorders Symptoms in Attention-Deficit/Hyperactivity Disorder: Significant Locus on Chromosome 7q11

    Science.gov (United States)

    Nijmeijer, Judith S.; Arias-Vásquez, Alejandro; Rommelse, Nanda N.; Altink, Marieke E.; Buschgens, Cathelijne J.; Fliers, Ellen A.; Franke, Barbara; Minderaa, Ruud B.; Sergeant, Joseph A.; Buitelaar, Jan K.; Hoekstra, Pieter J.; Hartman, Catharina A.

    2014-01-01

    We studied 261 ADHD probands and 354 of their siblings to assess quantitative trait loci associated with autism spectrum disorder symptoms (as measured by the Children's Social Behavior Questionnaire (CSBQ) using a genome-wide linkage approach, followed by locus-wide association analysis. A genome-wide significant locus for the CSBQ subscale…

  1. Multiple independent variants at the TERT locus are associated with telomere length and risks of breast and ovarian cancer

    NARCIS (Netherlands)

    Bojesen, Stig E.; Pooley, Karen A.; Johnatty, Sharon E.; Beesley, Jonathan; Michailidou, Kyriaki; Tyrer, Jonathan P.; Edwards, Stacey L.; Pickett, Hilda A.; Shen, Howard C.; Smart, Chanel E.; Hillman, Kristine M.; Mai, Phuong L.; Lawrenson, Kate; Stutz, Michael D.; Lu, Yi; Karevan, Rod; Woods, Nicholas; Johnstonw, Rebecca L.; French, Juliet D.; Chen, Xiaoqing; Weischer, Maren; Nielsen, Sune F.; Maranian, Melanie J.; Ghoussaini, Maya; Ahmed, Shahana; Baynes, Caroline; Bolla, Manjeet K.; Wang, Qin; Dennis, Joe; McGuffog, Lesley; Barrowdale, Daniel; Lee, Andrew; Healey, Sue; Lush, Michael; Tessier, Daniel C.; Vincent, Daniel; Bacot, Francis; Vergote, Ignace; Lambrechts, Sandrina; Despierre, Evelyn; Risch, Harvey A.; Gonzalez-Neira, Anna; Rossing, Mary Anne; Pita, Guillermo; Doherty, Jennifer A.; Alvarez, Nuria; Larson, Melissa C.; Fridley, Brooke L.; Schoof, Nils; Chang-Claude, Jenny; Cicek, Mine S.; Peto, Julian; Kalli, Kimberly R.; Broeks, Annegien; Armasu, Sebastian M.; Schmidt, Marjanka K.; Braaf, Linde M.; Winterhoff, Boris; Nevanlinna, Heli; Konecny, Gottfried E.; Lambrechts, Diether; Rogmann, Lisa; Guenel, Pascal; Teoman, Attila; Milne, Roger L.; Garcia, Joaquin J.; Cox, Angela; Shridhar, Vijayalakshmi; Burwinkel, Barbara; Marme, Frederik; Hein, Rebecca; Sawyer, Elinor J.; Haiman, Christopher A.; Wang-Gohrke, Shan; Andrulis, Irene L.; Moysich, Kirsten B.; Hopper, John L.; Odunsi, Kunle; Lindblom, Annika; Giles, Graham G.; Brenner, Hermann; Simard, Jacques; Lurie, Galina; Fasching, Peter A.; Carney, Michael E.; Radice, Paolo; Wilkens, Lynne R.; Swerdlow, Anthony; Goodman, Marc T.; Brauch, Hiltrud; Garcia-Closas, Montserrat; Hillemanns, Peter; Winqvist, Robert; Durst, Matthias; Devilee, Peter; Runnebaum, Ingo; Jakubowska, Anna; Lubinski, Jan; Mannermaa, Arto; Butzow, Ralf; Bogdanova, Natalia V.; Doerk, Thilo; Pelttari, Liisa M.; Zheng, Wei; Leminen, Arto; Anton-Culver, Hoda; Bunker, Clareann H.; Kristensen, Vessela; Ness, Roberta B.; Muir, Kenneth; Edwards, Robert; Meindl, Alfons; Heitz, Florian; Matsuo, Keitaro; du Bois, Andreas; Wu, Anna H.; Harter, Philipp; Teo, Soo-Hwang; Schwaab, Ira; Shu, Xiao-Ou; Blot, William; Hosono, Satoyo; Kang, Daehee; Nakanishi, Toru; Hartman, Mikael; Yatabe, Yasushi; Hamann, Ute; Karlan, Beth Y.; Sangrajrang, Suleeporn; Kjaer, Susanne Kruger; Gaborieau, Valerie; Jensen, Allan; Eccles, Diana; Hogdall, Estrid; Shen, Chen-Yang; Brown, Judith; Woo, Yin Ling; Shah, Mitul; Azmi, Mat Adenan Noor; Luben, Robert; Omar, Siti Zawiah; Czene, Kamila; Vierkant, Robert A.; Nordestgaard, Borge G.; Flyger, Henrik; Vachon, Celine; Olson, Janet E.; Wang, Xianshu; Levine, Douglas A.; Rudolph, Anja; Weber, Rachel Palmieri; Flesch-Janys, Dieter; Iversen, Edwin; Nickels, Stefan; Schildkraut, Joellen M.; Silva, Isabel Dos Santos; Cramer, Daniel W.; Gibson, Lorna; Terry, Kathryn L.; Fletcher, Olivia; Vitonis, Allison F.; van der Schoot, C. Ellen; Poole, Elizabeth M.; Hogervorst, Frans B. L.; Tworoger, Shelley S.; Liu, Jianjun; Bandera, Elisa V.; Li, Jingmei; Olson, Sara H.; Humphreys, Keith; Row, Irene; Blomqvist, Carl; Rodriguez-Rodriguez, Lorna; Aittomaki, Kristiina; Salvesen, Helga B.; Muranen, Taru A.; Wik, Elisabeth; Brouwers, Barbara; Krakstad, Camilla; Wauters, Els; Halle, Mari K.; Wildiers, Hans; Kiemeney, Lambertus A.; Mulot, Claire; Aben, Katja K.; Laurent-Puig, Pierre; Altena, Anne Mvan; Therese Truong, [No Value; Massuger, Leon F. A. G.; Benitez, Javier; Pejovic, Tanja; Arias Perez, Jose Ignacio; Hoatlin, Maureen; Zamora, M. Pilar; Cook, Linda S.; Balasubramanian, Sabapathy P.; Kelemen, Linda E.; Schneeweiss, Andreas; Le, Nhu D.; Sohn, Christof; Brooks-Wilson, Angela; Tomlinson, Ian; Kerin, Michael J.; Miller, Nicola; Cybulski, Cezary; Henderson, Brian E.; Menkiszak, Janusz; Schumacher, Fredrick; Wentzensen, Nicolas; Marchand, Loic Le; Yang, Hannah P.; Mulligan, Anna Marie; Glendon, Gord; Engelholm, Svend Aage; Knight, Julia A.; Hogdall, Claus K.; Apicella, Carmel; Gore, Martin; Tsimiklis, Helen; Song, Honglin; Southey, Melissa C.; Jager, Agnes; den Ouweland, Ans M. Wvan; Brown, Robert; Martens, John W. M.; Flanagan, James M.; Kriege, Mieke; Paul, James; Margolin, Sara; Siddiqui, Nadeem; Severi, Gianluca; Whittemore, Alice S.; Baglietto, Laura; McGuire, Valerie; Stegmaier, Christa; Sieh, Weiva; Mueller, Heiko; Arndt, Volker; Labreche, France; Gao, Yu-Tang; Goldberg, Mark S.; Yang, Gong; Dumont, Martine; McLaughlin, John R.; Hartmann, Arndt; Ekici, Arif B.; Beckmann, Matthias W.; Phelan, Catherine M.; Lux, Michael P.; Permuth-Wey, Jenny; Peissel, Bernard; Sellers, Thomas A.; Ficarazzi, Filomena; Barile, Monica; Ziogas, Argyrios; Ashworth, Alan; Gentry-Maharaj, Aleksandra; Jones, Michael; Ramus, Susan J.; Orr, Nick; Menon, Usha; Pearce, Celeste L.; Bruening, Thomas; Pike, Malcolm C.; Ko, Yon-Dschun; Lissowska, Jolanta; Figueroa, Jonine; Kupryjanczyk, Jolanta; Chanock, Stephen J.; Dansonka-Mieszkowska, Agnieszka; Jukkola-Vuorinen, Arja; Rzepecka, Iwona K.; Pylkas, Katri; Bidzinski, Mariusz; Kauppila, Saila; Hollestelle, Antoinette; Seynaeve, Caroline; Tollenaar, Rob A. E. M.; Durda, Katarzyna; Jaworska, Katarzyna; Hartikainen, Jaana M.; Kosma, Veli-Matti; Kataja, Vesa; Antonenkova, Natalia N.; Long, Jirong; Shrubsole, Martha; Deming-Halverson, Sandra; Lophatananon, Artitaya; Siriwanarangsan, Pornthep; Stewart-Brown, Sarah; Ditsch, Nina; Lichtner, Peter; Schmutzler, Rita K.; Ito, Hidemi; Iwata, Hiroji; Tajima, Kazuo; Tseng, Chiu-Chen; Stram, Daniel O.; van den Berg, David; Yip, Cheng Har; Ikrarn, M. Kamran; Teh, Yew-Ching; Cai, Hui; Lu, Wei; Signorello, Lisa B.; Cai, Qiuyin; Noh, Dong-Young; Yoo, Keun-Young; Miao, Hui; Iau, Philip Tsau-Choong; Teo, Yik Ying; McKay, James; Shapiro, Charles; Ademuyiwa, Foluso; Fountzilas, George; Hsiung, Chia-Ni; Yu, Jyh-Cherng; Hou, Ming-Feng; Healey, Catherine S.; Luccarini, Craig; Peock, Susan; Stoppa-Lyonnet, Dominique; Peterlongo, Paolo; Rebbeck, Timothy R.; Piedmonte, Marion; Singer, Christian F.; Friedman, Eitan; Thomassen, Mads; Offit, Kenneth; Hansen, Thomas V. O.; Neuhausen, Susan L.; Szabo, Csilla I.; Blanco, Ignacio; Garber, Judy; Narod, Steven A.; Weitzel, Jeffrey N.; Montagna, Marco; Olah, Edith; Godwin, Andrew K.; Yannoukakos, Drakoulis; Goldgar, David E.; Caldes, Trinidad; Imyanitov, Evgeny N.; Tihomirova, Laima; Arun, Banu K.; Campbell, Ian; Mensenkamp, Arjen R.; van Asperen, Christi J.; van Roozendaa, Kees E. P.; Meijers-Heijboer, Hanne; Collee, J. Margriet; Oosterwijk, Jan C.; Hooning, Maartje J.; Rookus, Matti A.; van der Luijt, Rob B.; Os, Theo A. Mvan; Evans, D. Gareth; Frost, Debra; Fineberg, Elena; Barwell, Julian; Walker, Lisa; Kennedy, M. John; Platte, Radka; Davidson, Rosemarie; Ellis, Steve D.; Cole, Trevor; Bressac-de Paillerets, Brigitte; Buecher, Bruno; Damiola, Francesca; Faivre, Laurence; Frenay, Marc; Sinilnikova, Olga M.; Caron, Olivier; Giraud, Sophie; Mazoyer, Sylvie; Bonadona, Valerie; Caux-Moncoutier, Virginie; Toloczko-Grabarek, Aleksandra; Gronwald, Jacek; Byrski, Tomasz; Spurdle, Amanda B.; Bonanni, Bernardo; Zaffaroni, Daniela; Giannini, Giuseppe; Bernard, Loris; Dolcetti, Riccardo; Manoukian, Siranoush; Arnold, Norbert; Engel, Christoph; Deissler, Helmut; Rhiem, Kerstin; Niederacher, Dieter; Pendl, Hansjoerg; Sutter, Christian; Wappenschmidt, Barbara; Borg, Ake; Mein, Beatrice; Rantala, Johanna; Soller, Maria; Nathanson, Katherine L.; Domchek, Susan M.; Rodriguez, Gustavo C.; Salani, Ritu; Kaulich, Daphne Gschwantler; Tea, Muy-Kheng; Paluch, Shani Shimon; Laitman, Yael; Skytte, Anne-Bine; Kruse, Torben A.; Jensen, Uffe Birk; Robson, Mark; Gerdes, Anne-Marie; Ejlertsen, Bent; Foretova, Lenka; Savage, Sharon A.; Lesterm, Jenny; Soucy, Penny; Kuchenbaecker, Karoline B.; Olswold, Curtis; Cunningham, Julie M.; Slager, Susan; Pankratz, Vernon S.; Dicks, Ed; Lakhani, Sunil R.; Couch, Fergus J.; Hall, Per; Monteiro, Alvaro N. A.; Gayther, Simon A.; Pharoah, Paul D. P.; Reddel, Roger R.; Goode, Ellen L.; Greene, Mark H.; Easton, Douglas F.; Berchuck, Andrew; Antoniou, Antonis C.; Chenevix-Trench, Georgia; Dunning, Alison M.

    2013-01-01

    TERT-locus SNPs and leukocyte telomere measures are reportedly associated with risks of multiple cancers. Using the Illumina custom genotyping array iCOG, we analyzed similar to 480 SNPs at the TERT locus in breast (n = 103,991), ovarian (n = 39,774) and BRCA1 mutation carrier (n = 11,705) cancer ca

  2. [Study of the transcriptional and transpositional activities of the Tirant retrotransposon in Drosophila melanogaster strains mutant for the flamenco locus].

    Science.gov (United States)

    Nefedova, L N; Urusov, F A; Romanova, N I; Shmel'kova, A O; Kim, A I

    2012-11-01

    Transpositions of the gypsy retrotransposon in the Drosophila melanogaster genome are controlled by the flamenco locus, which is represented as an accumulation of defective copies of transposable elements. In the present work, genetic control by the flamenco locus of the transcriptional and transpositional activities of the Tirant retrotransposon from the gypsy group was studied. Tissue-specific expression of Tirant was detected in the tissues of ovaries in a strain mutant for the flamenco locus. Tirant was found to be transpositionally active in isogenic D. melanogaster strains mutant for the flamenco locus. The sites of two new insertions have been localized by the method of subtractive hybridization. It has been concluded from the results obtained that the flamenco locus is involved in the genetic control of Tirant transpositions.

  3. Locus of Word Frequency Effects in Spelling to Dictation: Still at the Orthographic Level!

    Science.gov (United States)

    Bonin, Patrick; Laroche, Betty; Perret, Cyril

    2016-01-01

    The present study was aimed at testing the locus of word frequency effects in spelling to dictation: Are they located at the level of spoken word recognition (Chua & Rickard Liow, 2014) or at the level of the orthographic output lexicon (Delattre, Bonin, & Barry, 2006)? Words that varied on objective word frequency and on phonological…

  4. Illness perception in pediatric somatization and asthma: complaints and health locus of control beliefs

    Directory of Open Access Journals (Sweden)

    Bundschuh Silke

    2007-07-01

    Full Text Available Abstract Background Health- and illness-related cognitions of pediatric patients with asthma or somatization and of their caregivers are considered relevant for patient education and for cognitive-behavioral interventions. This study investigates the relationship between diagnosis and illness perception by child and parent in two different chronic conditions such as somatization disorder and asthma. Methods 25 patients with somatoform disorders and 25 patients with asthma bronchiale completed the Giessen Complaint List and the Multidimensional Health Locus of Control Scale. Primary caregivers independently answered parallel proxy-report instruments. Analyses of variance were performed to determine the impact of diagnosis and perspective. Correlations were calculated to determine the concordance between patient and caregiver reports. Results No statistically significant differences in illness locus of control beliefs were found between asthma and somatoform disorder children or parents. Parents reported more internal and fatalistic locus of control beliefs compared with their children. Correlations between patient and caregiver reports of symptoms and health locus of control beliefs were low to moderate. Conclusion Clinicians should take into account a sense of insufficient symptom control in both diagnostic groups and different viewpoints of patients and their parents.

  5. Fine-Mapping of the 1p11.2 Breast Cancer Susceptibility Locus

    DEFF Research Database (Denmark)

    Horne, Hisani N; Chung, Charles C; Zhang, Han

    2016-01-01

    The Cancer Genetic Markers of Susceptibility genome-wide association study (GWAS) originally identified a single nucleotide polymorphism (SNP) rs11249433 at 1p11.2 associated with breast cancer risk. To fine-map this locus, we genotyped 92 SNPs in a 900kb region (120,505,799-121,481,132) flanking...

  6. Genetic and molecular analysis of the tomato root-knot nematode resistance locus Mi-1.

    NARCIS (Netherlands)

    Liharska, T.

    1998-01-01

    Het doel van het onderzoek dat in dit proefschrift beschreven wordt, was de isolatie en karakterisering van het tomaat locus Mi-1, dat resistentie verleent tegen plantpathogene wortelknobbelaaltjes van het geslacht Meloidogyne, die schade veroorzaken bi

  7. The Relationship between STD Locus of Control and STD Acquisition among Adolescent Girls.

    Science.gov (United States)

    Rosenthal, Susan L.; Griffith, Jennifer O.; Succop, Paul A.; Biro, Frank M.; Lewis, Lisa M.; DeVellis, Robert F.; Stanberry, Lawrence R.

    2002-01-01

    Adolescent girls from an urban-based clinic participated in a longitudinal study about psychosexual development and risk of STD acquisition. The girls were asked about their perceptions of loci of control (parents, internal control) as it relates to STD acquisition. Responses to locus of control correlated over time but variations were not found…

  8. Warren-Spring based model for the shear yield locus of cohesive biomass powders

    Science.gov (United States)

    Vanneste-Ibarcq, Clément; Melkior, Thierry; de Ryck, Alain

    2017-06-01

    The objectives of this work are to determine accurately the cohesion of biomass powders from simple measures and to propose a new method for the description of the yield locus of powders with easy to measure parameters. The cohesion of 32 powders (wood, other biomasses and inorganic powders) have been analysed with two methods. The first method is the determination of the yield locus from shear tests at 3 kPa, performed with a powder rheometer, which gives an access to parameters such as cohesion (Y-intercept) and traction (X-intercept). The second method is the measurement of avalanche angles in a rotating drum. A linear relation is found between this angle and the cohesion length, ratio of the cohesion derived from the yield locus and the aerated density. Finally, a model is proposed for the prediction of the cohesion and the yield locus at 3 kPa, using only 2 parameters easy to measure: the avalanche angle and the aerated density.

  9. Loneliness among people with HIV in relation to locus of control and negative meta-stereotyping

    NARCIS (Netherlands)

    Gordijn, E.H.; Boven, G.

    2009-01-01

    The aim of this research was to examine the relation between locus of control, meta-stereotyping (expectancies about how one's group is stereotyped by another group), and loneliness among people who are HIV-positive. In line with expectations, a survey in the Netherlands among 122 people living with

  10. High-throughput development of genome-wide locus-specific informative SSR markers in wheat

    Science.gov (United States)

    Although simple sequence repeat (SSR) markers are not new, they are still useful and often used markers in molecular mapping and marker-assisted breeding, particularly in developing countries. However, locus-specific SSR markers could be more useful and informative in wheat breeding and genetic stud...

  11. Democratic Teacher Beliefs According to the Teacher's Gender and Locus of Control

    Science.gov (United States)

    Kesici, Sahin

    2008-01-01

    This study explored the variations in democratic beliefs among teachers based on gender and locus of control. The study groups comprised of 286 teachers. The results demonstrated that the level of adherence to democratic beliefs on the part of female teachers was significantly higher than those of male teachers, especially in terms of equality and…

  12. The Effects of Self-Care Instruction on Locus of Control in Children.

    Science.gov (United States)

    Blazek, Brodie; McClellan, Muriel S.

    1983-01-01

    A study focused on whether self-care instruction in health education can affect locus of control in fifth-grade students. Individual responsibility for self-care was encouraged. Results indicate that the instruction did increase the extent to which the children viewed health as the result of their own actions. (Author/PP)

  13. Personality disorder, emotional intelligence, and locus of control of patients with alcohol dependence

    Directory of Open Access Journals (Sweden)

    Om Prakash

    2015-01-01

    Full Text Available Aim: To assess personality disorder (PD, emotional intelligence (EI, and locus of control of alcohol dependent (AD patients and its comparison with normal controls. Materials and Methods: Based on purposive sampling technique, 33 AD patients were selected from the De-Addiction Ward of Ranchi Institute of Neuro-Psychiatry and Allied Sciences (RINPAS and 33 matched normal subjects were selected from Ranchi and nearby places. Both the groups were matched on various sociodemographic parameters, that is, age, gender, and socioeconomic level. All participants were assessed with Millon Clinical Multiaxial Inventory-III, Mangal EI Inventory, and Locus of Control scale. Obtained responses were scored by using standard scoring procedures and subsequently statistically analyzed by using Chi-square test. Results: AD patients have more comorbid pathological personality traits and disorders in comparison to their normal counterparts. Depressive, narcissistic, and paranoid PDs were prominent among AD group; followed by schizotypal, antisocial, negativistic, dependent, schizoid, sadistic, masochistic, and borderline PD. In comparison to normal participants, AD patients were significantly deficient in almost all the areas of EI and their locus of control was externally oriented. Conclusion: Patients with AD have significantly higher PDs, low EI, and an external orientation on the locus of control. Identification and management of these comorbid conditions are likely to improve the management and outcome of AD.

  14. The Effect of Compensation Studies on Disadvantaged Children's Self Concept Levels and Locus of Control

    Science.gov (United States)

    Sadioglu, Ömür

    2017-01-01

    The aim of this study is to determine the effect of "Bir Umut Ol Benim Için" (Be My Hope) project which was prepared for the children who were disadvantaged by being influenced from several risk factors as compared to their peers on the self-concepts and locus of controls of the children. The study group consisted of 33 children who were…

  15. RUNX1-dependent RAG1 deposition instigates human TCR-δ locus rearrangement

    NARCIS (Netherlands)

    A. Cieslak (Agata); S. le Noir (Sandrine); A. Trinquand (Amélie); L. Lhermitte; D.-M. Franchini (Don-Marc); P. Villarese (Patrick); S. Gon (Stéphanie); J. Bond (Jonathan); M. Simonin (Mathieu); L. Vanhile (Laurent); C. Reimann (Christian); E. Verhoeyen (Els); J. Larghero (Jerome); E. Six (Emmanuelle); S. Spicuglia (Salvatore); I. André-Schmutz (Isabelle); A.W. Langerak (Anton); B. Nadel (Bertrand); E.A. Macintyre (Elizabeth); D. Payet-Bornet (Dominique); V. Asnafi (Vahid)

    2014-01-01

    textabstractV(D)J recombination of TCR loci is regulated by chromatin accessibility to RAG1/2 proteins, rendering RAG1/2 targeting a potentially important regulator of lymphoid differentiation. We show that within the human TCR-α/δ locus, Dδ2-Dδ3 rearrangements occur at a very immature thymic,

  16. Locus of Control and Level of Conflict as Correlates of Immortality Orientation.

    Science.gov (United States)

    O'Dowd, William

    1985-01-01

    Assessed the orientation of 14 male professors toward immortality as a psychological motive. Results showed a generally low conscious concern with immortality issues; however, respondents who have accepted some sort of immortality show a more internal locus of control and better adjustment. (JAC)

  17. Evaluation of the plastic yield locus for embossed sheet using biaxial tensile tests

    Science.gov (United States)

    Kim, Young-Suk; Oh, Seok-Hwan; Do, Van-Cuong; Lee, Bong-Hyun

    2016-11-01

    3D-structured (embossed) aluminium sheets have been used as heat insulation materials in automotive exhaust parts because the embossments on the sheets increase the surface area and reinforce the stiffness of exhaust components. Unlike the press-forming process for flat (non-embossed) sheets, however, that for embossed aluminium sheets is constrained by many restrictions given the distinct mechanical properties and geometric 3D shape of the latter. In designing sheet-stamping tools, manufacturers have recently used CAE technologies based on finite element analysis. Guaranteeing the effectiveness of CAE technologies necessitates information about the plastic yield criterion, which is determined primarily by performing a biaxial tensile test on cruciform-shaped specimens. We measured the yield locus of an embossed aluminium 3004-P sheet by using the camera vision method instead of strain gauge measurement because of the difficulty in attaching a strain gauge to the central region of the aluminium body. The measured yield locus of the studied sheet shows that its yield stress in equi-biaxial stress is smaller than the flat sheet yield locus measured by the strain gauge method. The shape of the yield locus of the embossed aluminium sheet also adequately corresponds with Logan-Hosford anisotropic yield function.

  18. Fine-mapping of the 1p11.2 breast cancer susceptibility locus

    NARCIS (Netherlands)

    Horne, H.N. (Hisani N.); Chung, C.C. (Charles C.); Zhang, H. (Han); Yu, K. (Kai); Prokunina-Olsson, L. (Ludmila); K. Michailidou (Kyriaki); M.K. Bolla (Manjeet K.); Q. Wang (Qing); J. Dennis (Joe); J.L. Hopper (John); M.C. Southey (Melissa); M.K. Schmidt (Marjanka); A. Broeks (Annegien); K.R. Muir (K.); A. Lophatananon (Artitaya); P.A. Fasching (Peter); M.W. Beckmann (Matthias); O. Fletcher (Olivia); Johnson, N. (Nichola); E.J. Sawyer (Elinor); I.P. Tomlinson (Ian); Burwinkel, B. (Barbara); Marme, F. (Frederik); P. Guénel (Pascal); T. Truong (Thérèse); S.E. Bojesen (Stig); H. Flyger (Henrik); J. Benítez (Javier); A. González-Neira (Anna); H. Anton-Culver (Hoda); S.L. Neuhausen (Susan); Brenner, H. (Hermann); V. Arndt (Volker); A. Meindl (Alfons); R.K. Schmutzler (Rita); H. Brauch (Hiltrud); U. Hamann (Ute); H. Nevanlinna (Heli); S. Khan (Sofia); K. Matsuo (Keitaro); H. Iwata (Hiroji); T. Dörk (Thilo); N.V. Bogdanova (Natalia); A. Lindblom (Annika); S. Margolin (Sara); A. Mannermaa (Arto); V-M. Kosma (Veli-Matti); G. Chenevix-Trench (Georgia); A.H. Wu (Anna); Ven Den Berg, D. (David); A. Smeets (Ann); H. Zhao (Hui); J. Chang-Claude (Jenny); A. Rudolph (Anja); P. Radice (Paolo); M. Barile (Monica); F.J. Couch (Fergus); Vachon, C. (Celine); Giles, G.G. (Graham G.); R.L. Milne (Roger); C.A. Haiman (Christopher A.); L. Le Marchand (Loic); M.S. Goldberg (Mark); S.-H. Teo; N.A.M. Taib (Nur Aishah Mohd); V. Kristensen (Vessela); Borresen-Dale, A.-L. (Anne-Lise); W. Zheng (Wei); M. Shrubsole (Martha); R. Winqvist (Robert); A. Jukkola-Vuorinen (Arja); I.L. Andrulis (Irene); J.A. Knight (Julia); P. Devilee (Peter); C.M. Seynaeve (Caroline); M. García-Closas (Montserrat); K. Czene (Kamila); H. Darabi (Hatef); A. Hollestelle (Antoinette); J.W.M. Martens (John); J. Li (Jingmei); W. Lu (Wei); X.-O. Shu (Xiao-Ou); A. Cox (Angela); S.S. Cross (Simon); W.J. Blot (William); Q. Cai (Qiuyin); M. Shah (Mitul); C. Luccarini (Craig); Baynes, C. (Caroline); P. harrington (Patricia); D. Kang (Daehee); J.-Y. Choi (Ji-Yeob); J.M. Hartman (Joost); Chia, K.S. (Kee Seng); M. Kabisch (Maria); D. Torres (Diana); A. Jakubowska (Anna); J. Lubinski (Jan); S. Sangrajrang (Suleeporn); P. Brennan (Paul); S. Slager (Susan); D. Yannoukakos (Drakoulis); C.-Y. Shen (Chen-Yang); M.-F. Hou (Ming-Feng); A.J. Swerdlow (Anthony ); N. Orr (Nick); J. Simard (Jacques); P. Hall (Per); P.D.P. Pharoah (Paul); D.F. Easton (Douglas F.); Chanock, S.J. (Stephen J.); A.M. Dunning (Alison); J.D. Figueroa (Jonine)

    2016-01-01

    textabstractThe Cancer Genetic Markers of Susceptibility genome-wide association study (GWAS) originally identified a single nucleotide polymorphism (SNP) rs11249433 at 1p11.2 associated with breast cancer risk. To fine-map this locus, we genotyped 92 SNPs in a 900kb region (120,505,799-121,481,132)

  19. Locus of control, problem-solving skills appraisal as predictors of waste prevention behaviors

    Directory of Open Access Journals (Sweden)

    Karbalaei, S.

    2013-12-01

    Full Text Available Given that waste generation is a devastating problem, it is necessary that we advance our knowledge about the etiology of waste prevention behaviors. Accordingly, this study sought to increase the existing literature of waste prevention behaviors by examining the relationships among the locus of control, problem-solving confidence, approach-avoidance style, personal control style and participant’s age with waste prevention behaviors. Two hundred and forty participants (126 Women, and 114 men from Putra University (Universiti Putra Malaysia completed the Locus of Control of Behavior Scale, Waste Prevention Behaviors, Problem-Solving skills Appraisal and Socio-demographic questions. The Structural Equation Modeling (SEM estimated individuals with internal personal control, effective problem-solving confidence, internal locus of control and approaching styles were more likely to pursue waste prevention behaviors. In addition, men were better than women at problem-solving confidence, approaching style, while women were better than men at internal locus of control, and personal control style. Therefore, these findings reinforce the importance of personality traits in waste prevention behaviors.

  20. One-hybrid screens at the Saccharomyces cerevisiae HMR locus identify novel transcriptional silencing factors.

    Science.gov (United States)

    Andrulis, Erik D; Zappulla, David C; Alexieva-Botcheva, Krassimira; Evangelista, Carlos; Sternglanz, Rolf

    2004-01-01

    In Saccharomyces cerevisiae, genes located at the telomeres and the HM loci are subject to transcriptional silencing. Here, we report results of screening a Gal4 DNA-binding domain hybrid library for proteins that cause silencing when targeted to a silencer-defective HMR locus. PMID:15020450

  1. Relationship of Depression, Sociopathy, and Locus of Control to Treatment Outcome in Alcoholics

    Science.gov (United States)

    Caster, David U.; Parsons, Oscar A.

    1977-01-01

    Depression, sociopathy, and Levenson's tridimensional locus of control orientation were studied in four groups of veteran male alcoholics, who varied as to degree of benefit from therapeutic programs, and a group of controls. Higher depression scores were found in those groups that appeared to benefit less from treatment. (Author)

  2. The temporal locus of the interaction between working memory consolidation and the attentional blink

    NARCIS (Netherlands)

    Akyürek, E.G.; Leszczyński, Marcin; Schubö, Anna

    2010-01-01

    An increase in concurrent working memory load has been shown to amplify the attentional blink. The present study investigated the temporal locus of this phenomenon, by using a dual rapid serial visual presentation paradigm that enabled the measurement of lateralized event-related potentials. The P3

  3. Haplotype-based association analysis of the MAPT locus in Late Onset Alzheimer's disease

    Directory of Open Access Journals (Sweden)

    Morris John C

    2007-01-01

    Full Text Available Abstract Background Late onset Alzheimer's disease (LOAD is a common sporadic form of the illness, affecting individuals above the age of 65 yrs. A prominent hypothesis for the aetiopathology of Alzheimer's disease is that in the presence of a β-amyloid load, individuals expressing a pathogenic form of tau protein (MAPT are at increased risk for developing the disease. Genetic studies in this pursuit have, however, yielded conflicting results. A recent study showed a significant haplotype association (H1c with AD. The current study is an attempt to replicate this association in an independently ascertained cohort. Results In this report we present the findings of a haplotype analysis at the MAPT locus. We failed to detect evidence of association of the H1c haplotype at the MAPT locus with LOAD. None of the six SNPs forming the H1c haplotype showed evidence of association with disease. In addition, nested clade analysis suggested the presence of independent mutations at multiple points in the haplotype network or homoplasy at the MAPT locus. Such homoplasy can confound single SNP tests for association. We do not detect evidence that the set of SNPs forming the H1c haplotype in general or rs242557 in particular are pathogenic for LOAD. Conclusion In conclusion, we employed two contemporary haplotype analysis tools to perform haplotype association analysis at the MAPT locus. Our data suggest that the tagged SNPs forming the H1c haplotype do not have a causal role in the pathogenesis of LOAD.

  4. Role Stress Revisited: Job Structuring Antecedents, Work Outcomes, and Moderating Effects of Locus of Control

    Science.gov (United States)

    Conley, Sharon; You, Sukkyung

    2014-01-01

    A previous study examined role stress in relation to work outcomes; in this study, we added job structuring antecedents to a model of role stress and examined the moderating effects of locus of control. Structural equation modeling was used to assess the plausibility of our conceptual model, which specified hypothesized linkages among…

  5. Cognitive Dysfunction, Locus of Control and Treatment Outcome among Chronic Alcoholics.

    Science.gov (United States)

    Abbott, Max W.

    While alcoholism is no longer regarded as a unitary disorder, conventional measures of congition and personality have yet to be shown capable of consistently predicting clinical outcomes. To investigate cognitive dysfunction and locus of control as predictors of post treatment outcome in a large sample of alcoholics, 106 alcoholics (74 men, 32…

  6. Locus of Control and Computer Attitude: The Effect of User Involvement.

    Science.gov (United States)

    Hawk, Stephen R.

    1989-01-01

    Describes study that was conducted to investigate the relationship between locus of control and user attitude toward computer based information systems (CBIS) used at work. The impact of user involvement is examined, the hypotheses tested are described, and implications for introducing CBIS into organizations are discussed. (14 references) (LRW)

  7. Schema and Locus of Control as Predictors of Obsessive Compulsive Disorder

    Directory of Open Access Journals (Sweden)

    Hamidreza Akbarikia

    2012-12-01

    Full Text Available Objective: The study aimed to evaluate the correlation of maladjusted schema and locus of control with OCD, with the emphasis on cognitive approach to OCD. Method: In this study, 273 Iranian participants were selected; of whom,30% were male and 70% were female. Participants’age ranged from 19 to 34 and the mean age for the sample was 23.42(SD=2.46. Participants completed questionnaire batteries including measure of Levenson Locus of Control, Young Schema Scale and Y –bocsOCD Scale. One sample consisted of patients with a primary OCD according to DSM-IV criteria. The other sample selected for this cross-sectional study was university students.Result: Regression statistics item and reliability analysis were calculated with SPSS and LISREL software. Obsessive compulsive disorder was significantly predicted with both schema and powerful others’ locus of control, as these relations were large but association schema with OCDwas larger than the correlation OCD with powerful others (OCD with schema p.v<0.001 β=.47 and OCD with powerful others p.v<0.001 β=.15.Conclusion: The findings of the present study showed that schema and powerful others type of locus of control, were significantly related to both total OCD symptom severity and also to other sub scale of OCD. It is important to mention that schema can significantly predict all symptoms dimension of OCD. Furthermore, the analyses showed that schema was a strong predictor for obsessive thinking.

  8. Investigating Transfer of Large Chromosomal Regions Containing the Pathogenicity Locus Between Clostridium difficile Strains

    NARCIS (Netherlands)

    Brouwer, Mike; Mullany, P.; Allan, E.; Roberts, P.

    2016-01-01

    The genomes of all sequenced Clostridium difficile isolates contain multiple mobile genetic elements. The chromosomally located pathogenicity locus (PaLoc), encoding the cytotoxins TcdA and TcdB, was previously hypothesized to be a mobile genetic element; however, mobility was not demonstrated. Here

  9. Parenting Styles Influence on Locus of Control, Self-Efficacy and Academic Adjustment in College Students

    Science.gov (United States)

    Mills, Kimberly Tracey

    2010-01-01

    The purpose of this study was to investigate the relationship between perceived parenting style, locus of control, self-efficacy, and student outcome (i.e. academic performance, GPA) in a sample of college students. The relationship among gender and ethnicity were also examined across these variables. There were 100 participants in this study,…

  10. Genetic modifier loci of mouse Mfrp(rd6) identified by quantitative trait locus analysis.

    Science.gov (United States)

    Won, Jungyeon; Charette, Jeremy R; Philip, Vivek M; Stearns, Timothy M; Zhang, Weidong; Naggert, Jürgen K; Krebs, Mark P; Nishina, Patsy M

    2014-01-01

    The identification of genes that modify pathological ocular phenotypes in mouse models may improve our understanding of disease mechanisms and lead to new treatment strategies. Here, we identify modifier loci affecting photoreceptor cell loss in homozygous Mfrp(rd6) mice, which exhibit a slowly progressive photoreceptor degeneration. A cohort of 63 F2 homozygous Mfrp(rd6) mice from a (B6.C3Ga-Mfrp(rd6)/J × CAST/EiJ) F1 intercross exhibited a variable number of cell bodies in the retinal outer nuclear layer at 20 weeks of age. Mice were genotyped with a panel of single nucleotide polymorphism markers, and genotypes were correlated with phenotype by quantitative trait locus (QTL) analysis to map modifier loci. A genome-wide scan revealed a statistically significant, protective candidate locus on CAST/EiJ Chromosome 1 and suggestive modifier loci on Chromosomes 6 and 11. Multiple regression analysis of a three-QTL model indicated that the modifier loci on Chromosomes 1 and 6 together account for 26% of the observed phenotypic variation, while the modifier locus on Chromosome 11 explains only an additional 4%. Our findings indicate that the severity of the Mfrp(rd6) retinal degenerative phenotype in mice depends on the strain genetic background and that a significant modifier locus on CAST/EiJ Chromosome 1 protects against Mfrp(rd6)-associated photoreceptor loss.

  11. The benign concentric annular macular dystrophy locus maps to 6p12.3-q16.

    NARCIS (Netherlands)

    Lith-Verhoeven, J.J. van; Hoyng, C.B.; Helm, B. van den; Deutman, A.F.; Brink, H.M.A.; Kemperman, M.H.; Jong, W.H. de; Kremer, J.M.J.; Cremers, F.P.M.

    2004-01-01

    PURPOSE: To describe the clinical findings and to identify the genetic locus in a Dutch family with autosomal dominant benign concentric annular macular dystrophy (BCAMD). METHODS: All family members underwent ophthalmic examination. Linkage analysis of candidate retinal dystrophy loci and a whole g

  12. Perceived Social Support and Locus of Control as the Predictors of Vocational Outcome Expectations

    Science.gov (United States)

    Isik, Erkan

    2013-01-01

    The purpose of this study was to examine the relationships of vocational outcome expectation to social support which is an environmental factor and locus of control which is a personal factor. With this purpose, using Social Cognitive Career Theory as the theoretical framework, 263 undergraduate students completed Vocational Outcome Expectations…

  13. Expression of transgenes targeted to the Gt(ROSA26Sor locus is orientation dependent.

    Directory of Open Access Journals (Sweden)

    Douglas Strathdee

    Full Text Available BACKGROUND: Targeting transgenes to a chosen location in the genome has a number of advantages. A single copy of the DNA construct can be inserted by targeting into regions of chromatin that allow the desired developmental and tissue-specific expression of the transgene. METHODOLOGY: In order to develop a reliable system for reproducibly expressing transgenes it was decided to insert constructs at the Gt(ROSA26Sor locus. A cytomegalovirus (CMV promoter was used to drive expression of the Tetracycline (tet transcriptional activator, rtTA2(s-M2, and test the effectiveness of using the ROSA26 locus to allow transgene expression. The tet operator construct was inserted into one allele of ROSA26 and a tet responder construct controlling expression of EGFP was inserted into the other allele. CONCLUSIONS: Expression of the targeted transgenes was shown to be affected by both the presence of selectable marker cassettes and by the orientation of the transgenes with respect to the endogenous ROSA26 promoter. These results suggest that transcriptional interference from the endogenous gene promoter or from promoters in the selectable marker cassettes may be affecting transgene expression at the locus. Additionally we have been able to determine the optimal orientation for transgene expression at the ROSA26 locus.

  14. Relationship between Locus of Control and Alcohol and Drug-Related Behaviors in Teenagers.

    Science.gov (United States)

    Cox, William F., Jr.; Luhrs, Joyce A.

    1978-01-01

    Teenagers, classified according to Rotter's Locus of Control Scale, indicated whether or not and why they engaged in alcohol consumption or marijuana smoking. A higher proportion of externals drank but the groups did not generally differ in marijuana smoking behaviors. (Author/BEF)

  15. The Relation of Locus of Control, Anger, and Impulsivity to Boys' Aggressive Behavior

    Science.gov (United States)

    Deming, Annie M.; Lochman, John E.

    2008-01-01

    This study attempted to discover how anger, locus of control, and impulsivity are related to aggression. Two pathways to aggression were examined: a cognitive/schema pathway and an emotion/impulsivity pathway. The sample included 242 fourth- and fifth-grade boys. Using data from several questionnaires, teachers reported on levels of reactive and…

  16. The Association of External Locus of Control, Nonverbal Processing Difficulties, and Emotional Disturbance.

    Science.gov (United States)

    Nowicki, Stephen, Jr.; DiGirolamo, Ann

    1989-01-01

    The study with 20 emotionally disturbed and 20 nondisturbed subjects (ages 9-11) found that an external locus of control and poorer performance in decoding voice tone and facial expression were associated with emotional disturbance. Implications for teaching and remediation are discussed. (Author/DB)

  17. No intra-locus sexual conflict over reproductive fitness or ageing in field crickets.

    Directory of Open Access Journals (Sweden)

    Felix Zajitschek

    Full Text Available Differences in the ways in which males and females maximize evolutionary fitness can lead to intra-locus sexual conflict in which genes delivering fitness benefits to one sex are costly when expressed in the other. Trade-offs between current reproductive effort and future reproduction and survival are fundamental to the evolutionary biology of ageing. This leads to the prediction that sex differences in the optimization of age-dependent reproductive effort may generate intra-locus sexual conflict over ageing rates. Here we test for intra-locus sexual conflict over age-dependent reproductive effort and longevity in the black field cricket, Teleogryllus commodus. Using a half-sib breeding design, we show that the most important components of male and female reproductive effort (male calling effort and the number of eggs laid by females were positively genetically correlated, especially in early adulthood. However, the genetic relationships between longevity and reproductive effort were different for males and females, leading to low genetic covariation between male and female longevity. The apparent absence of intra-locus sexual conflict over ageing suggests that male and female longevity can evolve largely independently of one another.

  18. Role Stress Revisited: Job Structuring Antecedents, Work Outcomes, and Moderating Effects of Locus of Control

    Science.gov (United States)

    Conley, Sharon; You, Sukkyung

    2014-01-01

    A previous study examined role stress in relation to work outcomes; in this study, we added job structuring antecedents to a model of role stress and examined the moderating effects of locus of control. Structural equation modeling was used to assess the plausibility of our conceptual model, which specified hypothesized linkages among teachers'…

  19. Internal versus External Control of Reinforcement: A Review of the Locus of Control Construct

    Science.gov (United States)

    Kormanik, Martin B.; Rocco, Tonette S.

    2009-01-01

    One aspect of personality, perceptions of internal versus external control of reinforcement, shifts under conditions of change. This review of the literature examines the relationship between planned organizational change and locus of control. The review includes literature from the disciplines of clinical and social psychology, adult development,…

  20. A radiation hybrid map of chromosome ID reveals synteny conservation at a wheat speciation locus.

    Science.gov (United States)

    The species cytoplasm specific (scs) genes affect nuclear-cytoplasmic interactions in interspecific hybrids. A radiation hybrid (RH) mapping population of 188 individuals was employed to refine the location of the scsae locus of Tritcum aestivum chromosome 1D. ‘Wheat Zapper’, a comparative genomic...

  1. Why Adolescents Can't Read: Locus of Control, Gender, and Reading Abilities.

    Science.gov (United States)

    Nielsen, Linda; Long, Margaret

    1981-01-01

    Reveals that female high school seniors in a group of poor readers were significantly more external in locus of control than males in the group, but that no significant differences existed between females and males in a group of above-average readers. (FL)

  2. Locus of Semantic Interference in Picture Naming: Evidence From Dual-Task Performance

    NARCIS (Netherlands)

    Piai, V.; Roelofs, A.P.A.; Schriefers, H.J.

    2014-01-01

    Disagreement exists regarding the functional locus of semantic interference of distractor words in picture naming. This effect is a cornerstone of modern psycholinguistic models of word production, which assume that it arises in lexical response-selection. However, recent evidence from studies of du

  3. A Dual Reporter Mouse Model of the Human β-Globin Locus: Applications and Limitations

    NARCIS (Netherlands)

    P. Papadopoulos (Petros); L. Gutiérrez (Laura); R. van der Linden (Reinier); J. Kong-a-San (John); A. Maas (Alex); D.D. Drabek (Dubravka); G.P. Patrinos (George); J.N.J. Philipsen (Sjaak); F.G. Grosveld (Frank)

    2012-01-01

    textabstractThe human β-globin locus contains the β-like globin genes (i.e. fetal γ-globin and adult β-globin), which heterotetramerize with α-globin subunits to form fetal or adult hemoglobin. Thalassemia is one of the commonest inherited disorders in the world, which results in quantitative

  4. Locus of Control, Self-Reported Depression, and Perceived Causes of Depression

    Science.gov (United States)

    Calhoun, Lawrence G.; And Others

    1974-01-01

    Examines the relation of depression to locus of control and to the perceived causes of depression in a nonpsychiatric population. Findings suggest that adolescent females tend to hold themselves more responsible than males for unsatisfactory personal situations, and this extends to the attribution of causes for unhappy moods. (Author/PC)

  5. Locus of Control, Self-esteem, Stimulus Appraisal, and Depressive Symptoms in Children

    Science.gov (United States)

    Moyal, Barbara R.

    1977-01-01

    Variables of self-esteem, locus of control, stimulus appraisal, and depressive symptoms, which are related to depression in adults, were investigated in a sample of nonreferred Grade 5 and Grade 6 children. Grade and sex effects were not significant. All other intervariable correlations were significant. (Author)

  6. A variational Bayes algorithm for fast and accurate multiple locus genome-wide association analysis

    Directory of Open Access Journals (Sweden)

    Mezey Jason G

    2010-01-01

    Full Text Available Abstract Background The success achieved by genome-wide association (GWA studies in the identification of candidate loci for complex diseases has been accompanied by an inability to explain the bulk of heritability. Here, we describe the algorithm V-Bay, a variational Bayes algorithm for multiple locus GWA analysis, which is designed to identify weaker associations that may contribute to this missing heritability. Results V-Bay provides a novel solution to the computational scaling constraints of most multiple locus methods and can complete a simultaneous analysis of a million genetic markers in a few hours, when using a desktop. Using a range of simulated genetic and GWA experimental scenarios, we demonstrate that V-Bay is highly accurate, and reliably identifies associations that are too weak to be discovered by single-marker testing approaches. V-Bay can also outperform a multiple locus analysis method based on the lasso, which has similar scaling properties for large numbers of genetic markers. For demonstration purposes, we also use V-Bay to confirm associations with gene expression in cell lines derived from the Phase II individuals of HapMap. Conclusions V-Bay is a versatile, fast, and accurate multiple locus GWA analysis tool for the practitioner interested in identifying weaker associations without high false positive rates.

  7. Age Differences in Life Satisfaction, Locus of Control, and Self-Concept.

    Science.gov (United States)

    Nehrke, Milton F.; And Others

    1980-01-01

    Veterans Administration domiciliary residents in three age groups over age 50 completed measures of life satisfaction, locus of control and self-concept. Older veterans had resolved ego integrity v despair crisis more adequately than younger veterans. An institutional environment that facilitates self-esteem and satisfaction of elderly residents…

  8. Maximum likelihood estimates of two-locus recombination fractions under some natural inequality restrictions

    Directory of Open Access Journals (Sweden)

    Guo Jianhua

    2008-01-01

    Full Text Available Abstract Background The goal of linkage analysis is to determine the chromosomal location of the gene(s for a trait of interest such as a common disease. Three-locus linkage analysis is an important case of multi-locus problems. Solutions can be found analytically for the case of triple backcross mating. However, in the present study of linkage analysis and gene mapping some natural inequality restrictions on parameters have not been considered sufficiently, when the maximum likelihood estimates (MLEs of the two-locus recombination fractions are calculated. Results In this paper, we present a study of estimating the two-locus recombination fractions for the phase-unknown triple backcross with two offspring in each family in the framework of some natural and necessary parameter restrictions. A restricted expectation-maximization (EM algorithm, called REM is developed. We also consider some extensions in which the proposed REM can be taken as a unified method. Conclusion Our simulation work suggests that the REM performs well in the estimation of recombination fractions and outperforms current method. We apply the proposed method to a published data set of mouse backcross families.

  9. Internal versus External Control of Reinforcement: A Review of the Locus of Control Construct

    Science.gov (United States)

    Kormanik, Martin B.; Rocco, Tonette S.

    2009-01-01

    One aspect of personality, perceptions of internal versus external control of reinforcement, shifts under conditions of change. This review of the literature examines the relationship between planned organizational change and locus of control. The review includes literature from the disciplines of clinical and social psychology, adult development,…

  10. The Correlation of Nurses' job Burnout and Their Social Responsibility Considering the Role of Control Locus

    Directory of Open Access Journals (Sweden)

    Reyhane Izedi

    2016-07-01

    Full Text Available Background: Job burnout is an occupational hazard that reduces physical and mental energy of the staff. This study was aimed to investigate the relationship between the nurses' job burnout and their social responsibility considering the moderating role of control locus. Methods: In an analytical and cross-sectional study we used 3 valid questionnaires including Maslach burnout inventory, Dynson social responsibility and Rotter locus of control in 3 educational hospitals of Yazd, Iran. A total of 246 nurses contributed in the study. Data analysis was done through SPSS19. We used Pearson and Kendall correlation coefficient in data analysis. Findings: The mean scores of job burnout and social responsibility of studied group were 60.75 +8.37 and 71.84+15.47, respectively. Job burnout is negatively correlated with social responsibility statistically (r= -0.250 while locus of control acts as the moderator of this correlation. Conclusion: Our results suggest that creating a supportive work environment for nurses enhances their social responsibility trough affecting their level of job burnout. Also, the approved moderating role of control locus in the relationship of job burnout and social responsibility indicates that the personality traits can be considered as the appropriate criteria for entry to nursing schools.

  11. Assessment of Personality Types and Locus of Control in Multiple Sclerosis Patients

    Directory of Open Access Journals (Sweden)

    Sh. Mazaheri

    2008-07-01

    Full Text Available Introduction & Objective: Multiple sclerosis (MS is an autoimmune disease with unknown cause. MS is one of the disabling neurologic diseases in adult especially young range that myelin part of central nervous system (CNS is destructed. The aim of this study was assessment of types A and B personality and internal and external locus of control in multiple sclerosis (MS patients and comparison of the results with control group.Materials & Methods: In a case-control study, 30 patients with MS and 30 normal persons as control group evaluated with neurological examination, Rotter locus of control test and Friedman-Rosenman questionnaire for detection of types A and B personality. We employed to analyze the results.Results: 43 percent and 57 percent of MS patients had internal and external locus of control respectively. 63 percent and 37 percent of MS patients had type A and B personality respectively. 60 percent and 40 percent of control group had internal and external locus of control respectively. 20 percent and 80 percent of control group had type A and B personality respectively. Difference between personality type in two groups was significant (P<0.01.Conclusions: In this study, MS patients had more type A personality in comparison to control group.

  12. Health locus of control and self-esteem as related to adolescent health behavior and intentions.

    Science.gov (United States)

    Dielman, T E; Leech, S L; Lorenger, A T; Horvath, W J

    1984-01-01

    A health behavior and attitudes questionnaire was administered to 246 fifth-grade and 265 sixth-grade students during class time. The questions included 20 children's health locus of control (CHLC) items reported by Parcel and Meyer (1978), 17 children's self-esteem (CSE) items modified from those reported by Coopersmith (1967), and questions concerning past and current behavior and future intentions with respect to cigarette smoking, alcohol use, and marijuana use. The results indicate that the relationships between dimensions of children's health locus of control and self-esteem and their behaviors and intentions are not large enough to suggest that intervention programs directed at the prevention of detrimental health behaviors focus on the enhancement of self-esteem or the internal locus of control. An appropriate test of the efficacy of such an approach requires a longitudinal rather than a cross-sectional study, monitoring changes in the levels of self-esteem and health locus of control and associated changes in health behavior.

  13. Self-Esteem, Locus of Control and Various Aspects of Psychopathology of Adults with Visual Impairments

    Science.gov (United States)

    Papadopoulos, Konstantinos; Paralikas, Theodosis; Barouti, Marialena; Chronopoulou, Elena

    2014-01-01

    The exploratory study presented in this article looks into the possible differences in psychosocial aspects (self-esteem and locus of control) and aspects of psychopathology (depression, anxiety, melancholia, asthenia, and mania) amongst sighted adults and adults with visual impairments. Moreover, the study aims to examine the possible…

  14. Generalizability of Diagnostic-Prescriptive Teaching Strategies across Student Locus of Control and Multiple Instructional Units.

    Science.gov (United States)

    Benson, Jean S.; Yeany, Russell H.

    Reported is a study that explores the effect on student achievement of diagnostic-prescriptive instructional strategies on preservice elementary education majors (N=43) enrolled in an introductory biology course. Factors of pre-treatment achievement and locus of control were analyzed as well. Units on Mendelian genetics, modern genetics, and…

  15. Adolescent Parenting: Contrasts in Self-Esteem and Locus of Control.

    Science.gov (United States)

    Cook, Ann; Troike, Roger

    Pregnant and parenting adolescents represent a unique and challenging problem for educational systems. Of the 17,051 women who become pregnant every day in America, 2,795 or 16% of them are adolescents. The self-esteem and locus of control of 85 pregnant and parenting teens enrolled in the Ohio Graduation, Reality, Dual Role Skills (GRADS) Program…

  16. Work locus of control and dispositional optimism as antecedents to job insecurity

    Directory of Open Access Journals (Sweden)

    J Bosman

    2005-10-01

    Full Text Available The primary objective of this research was to investigate the relationship between job insecurity, work locus of control and dispositional optimism of employees working in two financial institutions (N = 605. Results showed a practically significant relationship between job insecurity and work locus of control, implying that external locus of control was associated with higher levels of job insecurity. It was furthermore found that increased levels of dispositional optimism were associated with decreased levels of job insecurity. Both work locus of control and dispositional optimism held predictive value with regard to job insecurity whilst controlling for the impact of demographic variables. Opsomming Die hoofdoelwit met hierdie studie was om die verhouding tussen werksonsekerheid, werk lokus van beheer en disposisionele optimisme te ondersoek van werknemers werksaam binne twee finansiële instellings (N = 605. ’n Dwarssneeopname-ontwerp is gebruik. Die resultate het aangetoon dat daar ’n prakties betekenisvolle verband bestaan tussen werk lokus van beheer en werksonsekerheid, wat beteken dat eksterne lokus van beheer geassosieer was met verhoogde vlakke van werksonsekerheid. Dit was verdermeer bevind dat verhoogde vlakke van disposisionele optimisme geassosieer was met laer vlakke van werksonsekerheid. Beide werk lokus van beheer and disposisionele optimisme het voorspellingswaarde met betrekking tot werksonsekerheid gehad terwyl die impak van demografiese veranderlikes gekontroleer is.

  17. Assessing God Locus of Control as a Factor in College Students' Alcohol Use and Sexual Behavior

    Science.gov (United States)

    Moore, Erin W.

    2014-01-01

    Objectives: This study explored God locus of control beliefs (ie, God's control over behavior) regarding their influence on alcohol use and sexual behavior as an alternative religiosity measure to religious behaviors, which does not capture perceived influence of religiosity. Additionally, demographic differences in religious beliefs were…

  18. Health locus of control, acculturation, and health-related Internet use among Latinas.

    Science.gov (United States)

    Roncancio, Angelica M; Berenson, Abbey B; Rahman, Mahbubur

    2012-01-01

    Among individuals residing in the United States, the Internet is the third most used source for obtaining health information. Little is known, however, about its use by Latinas. To understand health-related Internet use among Latinas, the authors examined it within the theoretical frameworks of health locus of control and acculturation. The authors predicted that acculturation would serve as a mediator between health locus of control and health-related Internet use, age and health-related Internet use, income and health-related Internet use, and education and health-related Internet use. Data were collected via a 25-minute self-report questionnaire. The sample consisted of 932 young (M age = 21.27 years), low-income Latinas. Using structural equation modeling, the authors observed that acculturation partially mediated the relation between health locus of control and health-related Internet use and fully mediated the relations among age, income, and Internet use. An internal health locus of control (p Internet use. The Internet is a powerful tool that can be used to effectively disseminate information to Latinas with limited access to health care professionals. These findings can inform the design of Internet-based health information dissemination studies targeting Latinas.

  19. Fine mapping of the chicken congenital loco locus on chromosome 12.

    Science.gov (United States)

    Okumura, Y; Ohtake, T; Uemoto, Y; Sato, S; Sato, S; Kobayashi, E

    2013-12-01

    Congenital loco in chicks is characterized by an apparent lack of control of the muscles of the neck. This disorder is inherited as a simple Mendelian recessive disease, caused by an autosomal recessive gene, lo. To date, there are no reports on the localization of this gene. The objective of this study was therefore to identify the genomic region of the lo locus. The experimental congenital loco population used here were selected from a Rhode Island Red (RIR) line and consisted of six generations, resulting in 124 chickens. A total of 113 DNA samples from offspring of four generations (G3, G4, G5, and G6) were used for genotyping. At first, genome-wide linkage mapping was performed using 122 microsatellite markers on 22 autosomal chromosomes, and the lo locus was mapped to chromosome 12. We then performed fine mapping in two steps on chromosome 12. First, the lo locus was mapped to the interval between GGA12_5 and GGA12_11 using 13 new polymorphic markers. In the second step, fine mapping was performed by adding new families and 11 additional new polymorphic markers. Linkage mapping and haplotype information enabled the localization of the lo locus to a 1.1-Mb region between GGA12_28 and GGA12_30. Genetic markers between GGA12_28 and GGA12_30 may be used to remove the carriers of congenital loco through this RIR line.

  20. TENDÊNCIA DO LOCUS DE CONTROLE DE PESSOAS DIABÉTICAS

    Directory of Open Access Journals (Sweden)

    Maria Lúcia Zanetti

    Full Text Available A tendência do locus de controle de pessoas diabéticas é a temática abordada no contexto do papel do enfermeiro enquanto educador. O trabalho teve como objetivos testar a fidedignidade do Instrumento de Medida de Locus de Controle à Saúde -IMLCS, confrontar a distribuição das respostas aos diferentes itens do IMLCS para uma população de pacientes diabéticos, e verificar a predominância do locus de controle à saúde nos sujeitos estudados. Os dados obtidos através da aplicação do referido instrumento em pacientes diabéticos permitiram-nos concluir que houve uma predominância de sujeitos com o locus do controle externo, que os diferentes itens foram respondidos de maneira favorável pelos sujeitos e que a escala está validada para a população de pacientes diabéticos. Acreditamos que os resultados obtidos apontam para a necessidade de se repensar o papel do enfermeiro frente às práticas educativas com pacientes diabéticos.

  1. The Exploration of the Associations between Locus of Control & High School Students’ Language Achievement

    Directory of Open Access Journals (Sweden)

    Abbas Eslami-Rasekh

    2012-07-01

    Full Text Available The purpose of the study is to determine the relationships between locus of control (LOC orientation and high school students’ language achievement. The popular categorization of internals and externals was taken into account. The participants of this study were 121 high school students in the second, third and pre-university grades in two public high schools of Isfahan, Iran. One of the instruments used in the study was an adopted version of Julian Rotters’ locus of control (1966 which identified internal and external orientations. The participants’ English scores were regarded as the measure of their achievement. Besides, a questionnaire consisting of 29 items was administered to all 121 students. Responses were put into one way and two-way ANOVA, the regression analysis, the independent t-test, chi-square and linear regression analysis to compare the means of two sets of scores. The findings of this study show a significant relationship between locus control and achievement of high school students. The findings can be used by EFL teachers and syllabus designers. Keywords: locus of control; high school students; language achievement; internals; externals

  2. Investigating Transfer of Large Chromosomal Regions Containing the Pathogenicity Locus Between Clostridium difficile Strains

    NARCIS (Netherlands)

    Brouwer, Mike; Mullany, P.; Allan, E.; Roberts, P.

    2016-01-01

    The genomes of all sequenced Clostridium difficile isolates contain multiple mobile genetic elements. The chromosomally located pathogenicity locus (PaLoc), encoding the cytotoxins TcdA and TcdB, was previously hypothesized to be a mobile genetic element; however, mobility was not demonstrated. Here

  3. Measures of Anomie and Locus-of-Control for Adolescents: Evidence of Factorial Validity.

    Science.gov (United States)

    Walters, Lynda Henley; Klein, Alice E.

    1981-01-01

    Two scales were submitted together for factor analyses in order to determine the extent to which the dimensions of locus of control and anomie were related from the perspective of adolescents. It was concluded that the instruments measure different constructs and are factorially valid when considered together. (Author/AL)

  4. Synthetic Human β-Globin 5'HS2 Constructs Function as Partially Active Locus Control Regions.

    NARCIS (Netherlands)

    J. Ellis (James); D. Talbot; N.O. Dillon (Niall); F.G. Grosveld (Frank)

    1993-01-01

    textabstractTransgenes linked to the beta-globin locus control region (LCR) are transcribed in a copy-dependent manner that is independent of the integration site. It has previously been shown that the LCR 5'HS2 region does not require its NF-E2 dimer binding site for LCR activity. In this paper we

  5. Locus of control and learning to cooperate in a prisoner's dilemma game

    NARCIS (Netherlands)

    Boone, C; De Brabander, B; Carree, M; de Jong, G; van Olffen, W; van Witteloostuijn, A

    2002-01-01

    Boone et al. (Boone, C., De Brabander, B., & van Witteloostuijn, A. (1999a). Locus of control and strategic behaviour in a prisoner's dilemma game. Personality and Individual Differences. 27, 695-706; Boone, C., De Brabander, B., & van Witteloostuijn, A. (1999b). The impact of personality on behavio

  6. A Nearly Non-Functional Mutant Allele of the Storage Protein Locus Hor2 in Barley

    DEFF Research Database (Denmark)

    Doll, Hans

    1980-01-01

    The low content of the storage protein fraction hordein-2 in the high-lysine mutant Risø 56 is due to a mutation at or near the locus Hor2 coding for hordein-2 polypeptides. The mutant gene is recessive in its qualitative effect on the electrophoretic banding pattern of hordein-2, but co...

  7. Coping Strategies and Locus of Control in Childhood Leukemia: A Multi-Center Research.

    Science.gov (United States)

    Polizzi, Concetta; Fontana, Valentina; Perricone, Giovanna; D'Angelo, Paolo; Jankovic, Momcilo; Taormina, Calogero; Nichelli, Francesca; Burgio, Sofia

    2015-05-25

    Acute lymphoblastic leukemia (ALL) is a very distressing experience for children and requires a special effort of adjustment. Therefore, it seems to be crucial to explore coping resources for the experienced risk condition. In this sense, the study focuses on coping strategies and locus of control in children with ALL during the treatment phase, and on their possible relation. The correlation between children and maternal coping strategies is also investigated. The participants involved were an experimental group of 40 children with ALL and their mothers, and 30 healthy children as the control group. The tools used were: the Child Behavioral Style Scale and the Monitor-Blunter Style Scale to assess the coping strategies of children and mothers; the locus of Control Scale for Children to analyze the children's perception of controlling the events. Both children with ALL and their mothers resorted to monitoring coping strategies with a statistically significant rate of occurrence (children: M=17.8, SD=3.8; mothers: M=10.48, SD=3.4). The data concerning the locus of control show this tendency towards internal causes (M=53.1, SD=4.7). There were statistically significant correlations between monitoring coping strategies and external locus of control (r=0.400, P<0.05). The results gained from the control group are almost equivalent. The outcomes show several interesting resources of the psychological functioning of children as well as of their mothers.

  8. Quantitative trait locus analysis of nitrogen use efficiency in barley (Hordeum vulgare L.)

    NARCIS (Netherlands)

    Kindu, G.A.; Tang, J.; Yin, X.; Struik, P.C.

    2014-01-01

    Quantitative trait locus (QTL) analysis of nitrogen use efficiency (NUE) of barley (Hordeum vulgare L.) was conducted on data generated from two pot experiments carried out in 2005 (using four nitrogen rates) and 2008 (with three rates) with AFLP markers and 94 recombinant inbred lines (RILs) of the

  9. [Self-esteem, resilience, locus of control and suicide risk in nursing students].

    Science.gov (United States)

    Montes-Hidalgo, Javier; Tomás-Sábado, Joaquín

    2016-01-01

    Assuming that suicide is the result of a series of factors acting cumulatively, the aim of this paper was to study the association of self-esteem, resilience and locus of control with the risk of suicidal behavior in a sample of nursing students. Observational, cross-sectional and correlational study with 186 nursing students who answered a questionnaire that contained, in addition to demographic data, the Spanish forms of Rosenberg self-esteem scale, the brief resilient coping scale, the Plutchik scale of suicide risk and the Rotter's internal-external locus of control scale. The scores of males and females are very similar on all scales except Locus of Control, where a significantly greater tendency of females attributed to external control. 6.4% of students have scores indicating suicide risk. Suicide risk scores correlated negatively and significantly with self-esteem and resilience and positively with locus of control. The multiple linear regression analysis identified self-esteem as the main variable related to suicide risk. The results suggest that students who have low self-esteem, have difficulty in adjusting to adverse situations and tend to the external attribution of the consequences of their actions may have an increased risk of suicidal behavior. Furthermore, the identification of self-esteem as the important factor involved in suicide risk can help in designing prevention programs. Copyright © 2016 Elsevier España, S.L.U. All rights reserved.

  10. The murine Th2 locus undergoes epigenetic modification in the thymus during fetal and postnatal ontogeny.

    Directory of Open Access Journals (Sweden)

    Momoko Yoshimoto

    Full Text Available Epigenetic modifications play a central role in the differentiation and function of immune cells in adult animals. Developmentally regulated epigenetic patterns also appear to contribute to the ontogeny of the immune system. We show here that the epigenetic profile of the T-helper (Th 2 locus undergoes changes in T lineage cells beginning in mid-gestation and extending throughout the first week of life. In particular, regulatory regions of the Th2 locus are largely methylated at CpG residues among fetal liver common lymphoid progenitor cells. The locus subsequently becomes highly hypomethylated among the downstream progeny of these cells within the fetal thymus. This hypomethylated state is preserved until birth when the locus becomes rapidly re-methylated, achieving adult-like status by 3-6 days post birth. Notably, the capacity for rapid, high level Th2 cytokine production is lost in parallel with this re-methylation. In vitro organ culture and in vivo transplantation experiments indicate that signals from the adult environment are required to achieve the postnatal methylated state. Together, these findings indicate that the Th2 bias of neonates may be conferred, in part, by an epigenetic profile inherited from fetal life. However, the fetal program is rapidly terminated post birth by the development of signals leading to the acquisition of adult-like epigenetic patterns.

  11. New cis-regulatory elements in the Rht-D1b locus region of wheat

    Science.gov (United States)

    Fifteen gene-containing BACs with accumulated length of 1.82-Mb from the Rht-D1b locus region weresequenced and compared in detail with the orthologous regions of rice, sorghum, and maize. Our results show that Rht-D1b represents a conserved genomic region as implied by high gene sequence identity...

  12. CUBN as a novel locus for end-stage renal disease : insights from renal transplantation

    NARCIS (Netherlands)

    Reznichenko, Anna; Snieder, Harold; van den Born, Jacob; de Borst, Martin H; Damman, Jeffrey; van Dijk, Marcory C R F; van Goor, Harry; Hepkema, Bouke G; Hillebrands, Jan-Luuk; Leuvenink, Henri G D; Niesing, Jan; Bakker, Stephan J L; Seelen, Marcus; Navis, Gerjan

    2012-01-01

    Chronic kidney disease (CKD) is a complex disorder. As genome-wide association studies identified cubilin gene CUBN as a locus for albuminuria, and urinary protein loss is a risk factor for progressive CKD, we tested the hypothesis that common genetic variants in CUBN are associated with end-stage r

  13. CUBN as a novel locus for end-stage renal disease: insights from renal transplantation.

    NARCIS (Netherlands)

    Reznichenko, A.; Snieder, H.; Born, J. van den; Borst, M.H. de; Damman, J.; Dijk, M.C.R.F. van; Goor, H. van; Hepkema, B.G.; Hillebrands, J.L.; Leuvenink, H.G.; Niesing, J.; Bakker, S.J.; Seelen, M.; Navis, G.

    2012-01-01

    Chronic kidney disease (CKD) is a complex disorder. As genome-wide association studies identified cubilin gene CUBN as a locus for albuminuria, and urinary protein loss is a risk factor for progressive CKD, we tested the hypothesis that common genetic variants in CUBN are associated with end-stage r

  14. Estimating null allele frequencies at a microsatellite locus in the oystercatcher (Haematopus ostralegus)

    NARCIS (Netherlands)

    Van Treuren, R

    1998-01-01

    A significant heterozygote deficiency was found for microsatellite locus 20H7 among adult breeding birds in four populations of the oystercatcher (Haematopus ostralegus). Genotype frequencies at seven other loci were according to Hardy-Weinberg equilibria. Deviations between observed and expected ge

  15. Phenotypic subregions within the split-hand/foot malformation 1 locus

    DEFF Research Database (Denmark)

    Rasmussen, Malene Bøgehus; Kreiborg, Sven; Jensen, Per

    2016-01-01

    phenotypic subregions within the SHFM1 locus associated with (1) isolated SHFM, (2) SHFM and hearing loss, and (3) SHFM, hearing loss, and craniofacial anomalies, respectively (ranked for increasing proximity to DLX5/6), and encompassing previously reported tissue-specific enhancers for DLX5/6. This uniquely...

  16. Human obesity associated with an intronic SNP in the brain-derived neurotrophic factor locus

    Science.gov (United States)

    Brain-derived neurotrophic factor (BDNF) plays a key role in energy balance. In population studies, SNPs of the BDNF locus have been linked to obesity, but the mechanism by which these variants cause weight gain is unknown. Here, we examined human hypothalamic BDNF expression in association with 44 ...

  17. Application of multi-locus analytical methods to identify interacting loci in case-control studies.

    NARCIS (Netherlands)

    Vermeulen, S.; Heijer, M. den; Sham, P.; Knight, J.

    2007-01-01

    To identify interacting loci in genetic epidemiological studies the application of multi-locus methods of analysis is warranted. Several more advanced classification methods have been developed in the past years, including multiple logistic regression, sum statistics, logic regression, and the multi

  18. Locus of marking typology in the possessive NP: A new approach

    NARCIS (Netherlands)

    van Rijn, M.

    2016-01-01

    This study takes a semantic approach to Nichols’ influential locus of marking typology, as applied to the possessive noun phrase. In this approach, a careful distinction is made between two semantic types of dependency relations: those between inherently relational nouns and their argument

  19. Deletion of tumor progression locus 2 attenuates alcohol induced hepatic inflammation

    Science.gov (United States)

    BACKGROUND: The pathogenesis of alcoholic liver disease (ALD) involves the interaction of several inflammatory signaling pathways. Tumor progression locus 2 (TPL2), also known as Cancer Osaka Thyroid (COT) and MAP3K8, is a serine threonine kinase that functions as a critical regulator of inflammator...

  20. Self-Esteem, Locus of Control and Various Aspects of Psychopathology of Adults with Visual Impairments

    Science.gov (United States)

    Papadopoulos, Konstantinos; Paralikas, Theodosis; Barouti, Marialena; Chronopoulou, Elena

    2014-01-01

    The exploratory study presented in this article looks into the possible differences in psychosocial aspects (self-esteem and locus of control) and aspects of psychopathology (depression, anxiety, melancholia, asthenia, and mania) amongst sighted adults and adults with visual impairments. Moreover, the study aims to examine the possible…

  1. Relation Between Death Anxiety, Belief in Afterlife, and Locus of Control

    Science.gov (United States)

    Berman, Alan L.; Hays, James E.

    1973-01-01

    College-age students were given a four-part questionnaire consisting of: (1) Rotter's Internal-External Locus of Control Scale, (2) the Belief in Afterlife Scale-Form A, (3) Templer's Death Anxiety Scale, and (4) Lester's Fear of Death Scale. In general, the findings suggest that the relationship between death and afterlife beliefs is weak.…

  2. 19p13.1 Is a triple-negative-specific breast cancer susceptibility locus

    NARCIS (Netherlands)

    K. Stevens (Kristen); Z. Fredericksen (Zachary); C. Vachon (Celine); X. Wang (Xing); S. Margolin (Sara); A. Lindblom (Annika); H. Nevanlinna (Heli); D. Greco (Dario); K. Aittomäki (Kristiina); C. Blomqvist (Carl); J. Chang-Claude (Jenny); A. Vrieling (Alina); D. Flesch-Janys (Dieter); H.-P. Sinn (Hans-Peter); S. Wang-Gohrke (Shan); S. Nickels (Stefan); H. Brauch (Hiltrud); Y-D. Ko (Yon-Dschun); H.-P. Fischer; R.K. Schmutzler (Rita); A. Meindl (Alfons); C.R. Bartram (Claus); S. Schott (Sarah); C. Engel (Christoph); A.K. Godwin (Andrew); J. Weaver (JoEllen); S.S. Pathak; P. Sharma (Pankaj); H. Brenner (Hermann); H. Mul̈ler (Heiko); V. Arndt (Volker); C. Stegmaier (Christa); P. Miron (Penelope); D. Yannoukakos (Drakoulis); A. Stavropoulou (Alexandra); G. Fountzilas (George); H. Gogas (Helen); R. Swann (Ruth); M. Dwek (Miriam); A. Perkins (Annie); R.L. Milne (Roger); J. Benítez (Javier); M.P. Zamora (Pilar); J.I.A. Perez (Jose Ignacio Arias); S.E. Bojesen (Stig); S.F. Nielsen (Sune); B.G. Nordestgaard (Børge); H. Flyger (Henrik); P. Guénel (Pascal); T. Truong (Thérèse); F. Menegaux (Florence); E. Cordina-Duverger (Emilie); B. Burwinkel (Barbara); F. Marme (Federick); A. Schneeweiss (Andreas); C. Sohn (Christof); E.J. Sawyer (Elinor); I.P. Tomlinson (Ian); M. Kerin (Michael); J. Peto (Julian); N. Johnson (Nichola); O. Fletcher (Olivia); I. dos Santos Silva (Isabel); P.A. Fasching (Peter); M.W. Beckmann (Matthias); A. Hartmann; A.B. Ekici (Arif); A. Lophatananon (Artitaya); K.R. Muir (Kenneth); P. Puttawibul (Puttisak); S. Wiangnon (Surapon); M.K. Schmidt (Marjanka); A. Broeks (Annegien); L.M. Braaf (Linde); E.H. Rosenberg (Efraim); J.L. Hopper (John); C. Apicella (Carmel); D.J. Park (Daniel); M.C. Southey (Melissa); A.J. Swerdlow (Anthony ); A. Ashworth (Alan); O. Nicholas (Orr); M. Schoemaker (Minouk); H. Anton-Culver (Hoda); A. Ziogas (Argyrios); L. Bernstein (Leslie); C.C. Dur (Christina Clarke); C-Y. Shen (Chen-Yang); J-C. Yu (Jyh-Cherng); H.-M. Hsu (Huan-Ming); C.-N. Hsiung (Chia-Ni); U. Hamann (Ute); T. Dun̈nebier (Thomas); T. Rud̈iger (Thomas); H.U. Ulmer (Hans); P.D.P. Pharoah (Paul); A.M. Dunning (Alison); M.K. Humphreys (Manjeet); Q. Wang (Qing); A. Cox (Angela); S.S. Cross (Simon); M.W.R. Reed (Malcolm); P. Hall (Per); K. Czene (Kamila); C.B. Ambrosone (Christine); F. Ademuyiwa (Foluso); H. Hwang (Helena); D. Eccles (Diana); M. García-Closas (Montserrat); J.D. Figueroa (Jonine); M.E. Sherman (Mark); J. Lissowska (Jolanta); P. Devilee (Peter); C.M. Seynaeve (Caroline); R.A.E.M. Tollenaar (Rob); M.J. Hooning (Maartje); I.L. Andrulis (Irene); J.A. Knight (Julia); G. Glendon (Gord); A.M. Mulligan (Anna Marie); R. Winqvist (Robert); K. Pykäs (Katri); A. Jukkola-Vuorinen (Arja); M. Grip (Mervi); E.M. John (Esther); A. Miron (Alexander); G.G. Alnæs (Grethe); V. Kristensen (Vessela); A.-L. Brøresen-Dale (Anne-Lise); G.G. Giles (Graham); L. Baglietto (Laura); C.A. McLean (Catriona Ann); G. Severi (Gianluca); M. Kosel (Matthew); V.S. Pankratz (Shane); S. Slager (Susan); J.E. Olson (Janet); P. Radice (Paolo); P. Peterlongo (Paolo); S. Manoukian (Siranoush); M. Barile (Monica); D. Lambrechts (Diether); S. Hatse (Sigrid); A.-S. Dieudonné (Anne-Sophie); M.R. Christiaens (Marie Rose); G. Chenevix-Trench (Georgia); J. Beesley (Jonathan); X. Chen (Xiaoqing); A. Mannermaa (Arto); V-M. Kosma (Veli-Matti); J. Hartikainen (Jaana); Y. Soini (Ylermi); D.F. Easton (Douglas); F.J. Couch (Fergus)

    2012-01-01

    textabstractThe 19p13.1 breast cancer susceptibility locus is a modifier of breast cancer risk in BRCA1 mutation carriers and is also associated with the risk of ovarian cancer. Here, we investigated 19p13.1 variation and risk of breast cancer subtypes, defined by estrogen receptor (ER),

  3. Fine-mapping of the 1p11.2 breast cancer susceptibility locus

    NARCIS (Netherlands)

    Horne, H.N. (Hisani N.); Chung, C.C. (Charles C.); Zhang, H. (Han); Yu, K. (Kai); Prokunina-Olsson, L. (Ludmila); K. Michailidou (Kyriaki); M.K. Bolla (Manjeet K.); Q. Wang (Qing); J. Dennis (Joe); J.L. Hopper (John); M.C. Southey (Melissa); M.K. Schmidt (Marjanka); A. Broeks (Annegien); K.R. Muir (K.); A. Lophatananon (Artitaya); P.A. Fasching (Peter); M.W. Beckmann (Matthias); O. Fletcher (Olivia); Johnson, N. (Nichola); E.J. Sawyer (Elinor); I.P. Tomlinson (Ian); Burwinkel, B. (Barbara); Marme, F. (Frederik); P. Guénel (Pascal); T. Truong (Thérèse); S.E. Bojesen (Stig); H. Flyger (Henrik); J. Benítez (Javier); A. González-Neira (Anna); H. Anton-Culver (Hoda); S.L. Neuhausen (Susan); Brenner, H. (Hermann); V. Arndt (Volker); A. Meindl (Alfons); R.K. Schmutzler (Rita); H. Brauch (Hiltrud); U. Hamann (Ute); H. Nevanlinna (Heli); S. Khan (Sofia); K. Matsuo (Keitaro); H. Iwata (Hiroji); T. Dörk (Thilo); N.V. Bogdanova (Natalia); A. Lindblom (Annika); S. Margolin (Sara); A. Mannermaa (Arto); V-M. Kosma (Veli-Matti); G. Chenevix-Trench (Georgia); A.H. Wu (Anna); Ven Den Berg, D. (David); A. Smeets (Ann); H. Zhao (Hui); J. Chang-Claude (Jenny); A. Rudolph (Anja); P. Radice (Paolo); M. Barile (Monica); F.J. Couch (Fergus); Vachon, C. (Celine); Giles, G.G. (Graham G.); R.L. Milne (Roger); C.A. Haiman (Christopher A.); L. Le Marchand (Loic); M.S. Goldberg (Mark); S.-H. Teo; N.A.M. Taib (Nur Aishah Mohd); V. Kristensen (Vessela); Borresen-Dale, A.-L. (Anne-Lise); W. Zheng (Wei); M. Shrubsole (Martha); R. Winqvist (Robert); A. Jukkola-Vuorinen (Arja); I.L. Andrulis (Irene); J.A. Knight (Julia); P. Devilee (Peter); C.M. Seynaeve (Caroline); M. García-Closas (Montserrat); K. Czene (Kamila); H. Darabi (Hatef); A. Hollestelle (Antoinette); J.W.M. Martens (John); J. Li (Jingmei); W. Lu (Wei); X.-O. Shu (Xiao-Ou); A. Cox (Angela); S.S. Cross (Simon); W.J. Blot (William); Q. Cai (Qiuyin); M. Shah (Mitul); C. Luccarini (Craig); Baynes, C. (Caroline); P. harrington (Patricia); D. Kang (Daehee); J.-Y. Choi (Ji-Yeob); J.M. Hartman (Joost); Chia, K.S. (Kee Seng); M. Kabisch (Maria); D. Torres (Diana); A. Jakubowska (Anna); J. Lubinski (Jan); S. Sangrajrang (Suleeporn); P. Brennan (Paul); S. Slager (Susan); D. Yannoukakos (Drakoulis); C.-Y. Shen (Chen-Yang); M.-F. Hou (Ming-Feng); A.J. Swerdlow (Anthony ); N. Orr (Nick); J. Simard (Jacques); P. Hall (Per); P.D.P. Pharoah (Paul); D.F. Easton (Douglas F.); Chanock, S.J. (Stephen J.); A.M. Dunning (Alison); J.D. Figueroa (Jonine)

    2016-01-01

    textabstractThe Cancer Genetic Markers of Susceptibility genome-wide association study (GWAS) originally identified a single nucleotide polymorphism (SNP) rs11249433 at 1p11.2 associated with breast cancer risk. To fine-map this locus, we genotyped 92 SNPs in a 900kb region (120,505,799-121,481,132)

  4. Optimization of STR locus enrichment for STR profiling of fragmented DNA.

    Science.gov (United States)

    Ham, Seon-Kyu; Kim, Se-Yong; Ahn, Jang-Won; Seo, Bo Young; Woo, Kwang-Man; Choi, Cheol Yong; Lee, Seung-Hwan

    2014-11-01

    DNA degradation is a major obstacle in gaining an accurate profile with standard DNA typing technology. Although alternative genotyping strategies such as mini-STRs and SNPs have proven to be more successful in profiling degraded DNA, these approaches also have limitations. Here, we show that locus enrichment by hybridization of degraded genomic DNA with an STR locus-specific biotinylated oligonucleotide is a powerful approach to overcome problems in STR typing of highly degraded DNA. An experimental investigation of factors affecting the efficiency of this method indicates that the choice of primer and molar ratio of primers to genomic DNA are critical factors in improving enrichment of the STR locus before genotyping with multiplex kits. In addition, we find that indirect capture rather than direct capture with magnetic beads yields better enrichment efficiency for STR locus enrichments. Using these strategies, we demonstrate an improvement in STR typing of DNA from cultured cells damaged by exposure to sunlight or UV. We suggest that this approach could be applied to highly degraded forensic samples alone or in combination with mini-STRs.

  5. Measures of Anomie and Locus-of-Control for Adolescents: Evidence of Factorial Validity.

    Science.gov (United States)

    Walters, Lynda Henley; Klein, Alice E.

    1981-01-01

    Two scales were submitted together for factor analyses in order to determine the extent to which the dimensions of locus of control and anomie were related from the perspective of adolescents. It was concluded that the instruments measure different constructs and are factorially valid when considered together. (Author/AL)

  6. A schizophrenia-associated HLA locus affects thalamus volume and asymmetry

    NARCIS (Netherlands)

    Brucato, N.; Guadalupe, T.; Franke, B.; Fisher, S.E.; Francks, C.

    2015-01-01

    Genes of the Major Histocompatibility Complex (MHC) have recently been shown to have neuronal functions in the thalamus and hippocampus. Common genetic variants in the Human Leukocyte Antigens (HLA) region, human homologue of the MHC locus, are associated with small effects on susceptibility to

  7. Single-locus complementary sex determination in the inbreeding wasp Euodynerus foraminatus Saussure (Hymenoptera: Vespidae).

    Science.gov (United States)

    Stahlhut, J K; Cowan, D P

    2004-03-01

    The Hymenoptera have arrhenotokous haplodiploidy in which males normally develop from unfertilized eggs and are haploid, while females develop from fertilized eggs and are diploid. Multiple sex determination systems are known to underlie haplodiploidy, and the best understood is single-locus complementary sex determination (sl-CSD) in which sex is determined at a single polymorphic locus. Individuals heterozygous at the sex locus develop as females; individuals that are hemizygous (haploid) or homozygous (diploid) at the sex locus develop as males. sl-CSD can be detected with inbreeding experiments that produce diploid males in predictable proportions as well as sex ratio shifts due to diploid male production. This sex determination system is considered incompatible with inbreeding because the ensuing increase in homozygosity increases the production of diploid males that are inviable or infertile, imposing a high cost on matings between close relatives. However, in the solitary hunting wasp Euodynerus foraminatus, a species suspected of having sl-CSD, inbreeding may be common due to a high incidence of sibling matings at natal nests. In laboratory crosses with E. foraminatus, we find that sex ratios and diploid male production (detected as microsatellite heterozygosity) are consistent with sl-CSD, but not with other sex determination systems. This is the first documented example of sl-CSD in a hymenopteran with an apparent natural history of inbreeding, and thus presents a paradox for our understanding of hymenopteran genetics.

  8. Christianity or Superstition? Effects on Locus of Control and Well-Being.

    Science.gov (United States)

    Wong-McDonald, Ana; Gorsuch, Richard L.

    Various studies have related superstition to religion, describing the two terms synonymously. However, religion is a highly variable construct which must be measured more discriminately. In this study, superstition was examined in relation to God Concepts, locus of control, and Spiritual Well-Being. Results obtained from 151 Christian…

  9. [Significance of additional RFLP single locus probes analysis after STR based determination of sibship].

    Science.gov (United States)

    Mályusz, Victoria; Schmidt, Maren; Simeoni, Eva; Poetsch, Micaela; Schwark, Thorsten; Oehmichen, Manfred; von Wurmb-Schwark, Nicole

    2007-01-01

    Autosomal STR typing alone seems to be no sufficient tool for resolving deficiency cases (e.g. cases of questioned paternity or half-sibships). Therefore, we investigated whether the additional analysis of RFLP single locus probes can improve the solution of such complicated kinship cases. We analyzed 207 children and men from 101 families using the AmpFlSTRIdentifiler multiplex PCR kit and three RFLP single locus probes. A comparison between each child and all unrelated men resulted in 11,023 man / child pairs. Less than three excluding STRs were found in 125 child / unrelated man pairs (1.13%). Additional analysis of RFLP results reduced the number of ambiguous cases to 35. Half-sibling pairs were simulated using STR results from 20 cases with high paternity probabilities (group 1) and relatively low paternity probabilities (group 2). Using a commercially available computer program we calculated probabilities for 778 half-sibling pairs. In 35 pairs (4.49%) half-sibling probabilities over 90.0% could be calculated. Additional investigation of RFLP single locus probes did not lead to a more reliable evaluation of these results. The combined investigation of autosomal STRs and RFLP single locus probes can satisfactorily solve deficient paternities but does not contribute to the solution of questioned half-sibships.

  10. A new strategy for estimating two-locus recombination fractions under some natural inequality restrictions

    Indian Academy of Sciences (India)

    Ying Zhou; Weijun Ma; Xiaona Sheng; Huakun Wang

    2011-08-01

    Linkage analysis is now being widely used to map markers on each chromosome in the human genome, to map genetic diseases, and to identify genetic forms of common diseases. Two-locus linkage analysis and multi-locus analysis have been investigated comprehensively, and many computer programs have been developed to perform linkage analysis. Yet there exists a shortcoming in traditional methods, i.e., the parameter space of two-locus recombination fractions has not been emphasized sufficiently in the usual analyses. In this paper, we propose a new strategy for estimating the two-locus recombination fractions based on data of backcross family in the framework of some natural and necessary parameter restrictions. The new strategy is based on a restricted projection algorithm, which can provide fast reasonable estimates of recombination fraction, and can therefore serve as a superior alternative algorithm. Results obtained from both real and simulated data indicate that the new algorithm performs well in the estimation of recombination fractions and outperforms current methods.

  11. Self efficacy, social acceptance and locus of control as predictors of social interest among Iranian students

    Directory of Open Access Journals (Sweden)

    Vahid Ataie Moghanloo

    2017-07-01

    Full Text Available Social interest is human phenomenon which can be considered as structure of personality in psychology. This descriptive correlation study aimed to investigate self efficacy, social acceptance and locus of control as predictors of social interest. This was correlational study. The sample consisted of 153 boys and 147 girls who were studying at private middle schools. Multistage cluster sampling method was used. General self efficacy questionnaire, marlowe-crowne social desirability scale, Rotter's Locus of control scale and sulliman scale of social interest were used to collect data. The level of significance was at 5%. The results showed that social interest had significant positive relationship with self efficacy and social acceptability and hadsignificant negative relationship with locus of control. Three variables of self efficacy, social acceptance and locus of control were able to explain about 59% of social interest variance. According to obtained results about social interest in adolescents and also consider other predictors in this context appropriate training promotion of social interest should be used and developed.

  12. Coping strategies and locus of control in childhood leukemia: a multi-center research

    Directory of Open Access Journals (Sweden)

    Concetta Polizzi

    2015-06-01

    Full Text Available Acute lymphoblastic leukemia (ALL is a very distressing experience for children and requires a special effort of adjustment. Therefore, it seems to be crucial to explore coping resources for the experienced risk condition. In this sense, the study focuses on coping strategies and locus of control in children with ALL during the treatment phase, and on their possible relation. The correlation between children and maternal coping strategies is also investigated. The participants involved were an experimental group of 40 children with ALL and their mothers, and 30 healthy children as the control group. The tools used were: the Child Behavioral Style Scale and the Monitor-Blunter Style Scale to assess the coping strategies of children and mothers; the locus of Control Scale for Children to analyze the children’s perception of controlling the events. Both children with ALL and their mothers resorted to monitoring coping strategies with a statistically significant rate of occurrence (children: M=17.8, SD=3.8; mothers: M=10.48, SD=3.4. The data concerning the locus of control show this tendency towards internal causes (M=53.1, SD=4.7. There were statistically significant correlations between monitoring coping strategies and external locus of control (r=0.400, P<0.05. The results gained from the control group are almost equivalent. The outcomes show several interesting resources of the psychological functioning of children as well as of their mothers.

  13. Direct visualization of the highly polymorphic RNU2 locus in proximity to the BRCA1 gene.

    Directory of Open Access Journals (Sweden)

    Chloé Tessereau

    Full Text Available Although the breast cancer susceptibility gene BRCA1 is one of the most extensively characterized genetic loci, much less is known about its upstream variable number tandem repeat element, the RNU2 locus. RNU2 encodes the U2 small nuclear RNA, an essential splicing element, but this locus is missing from the human genome assembly due to the inherent difficulty in the assembly of repetitive sequences. To fill the gap between RNU2 and BRCA1, we have reconstructed the physical map of this region by re-examining genomic clone sequences of public databases, which allowed us to precisely localize the RNU2 array 124 kb telomeric to BRCA1. We measured by performing FISH analyses on combed DNA for the first time the exact number of repeats carried by each of the two alleles in 41 individuals and found a range of 6-82 copies and a level of heterozygosity of 98%. The precise localisation of the RNU2 locus in the genome reference assembly and the implementation of a new technical tool to study it will make the detailed exploration of this locus possible. This recently neglected macrosatellite could be valuable for evaluating the potential role of structural variations in disease due to its location next to a major cancer susceptibility gene.

  14. Identification of a novel locus for a USH3 like syndrome combined with congenital cataract

    DEFF Research Database (Denmark)

    Dad, S.; Østergaard, Elsebet; Thykjær, T.

    2010-01-01

    Danish family of Dutch descent, we have identified a novel locus for a rare USH3-like syndrome. The affected family members have a unique association of retinitis pigmentosa, progressive hearing impairment, vestibular dysfunction, and congenital cataract. The phenotype is similar, but not identical...

  15. Adaptations in Locus Coeruleus Induced by Post-Traumatic Stress Disorder

    Science.gov (United States)

    2013-11-01

    mitochondrial nitric oxide synthase and citric acid cycle , Biochimica et Biophysica Acta (BBA) - Bioenergetics 1658, 64–71 (2004). 11. M. E. Carter et al...norepinephrine-containing locus coeruleus neurons in behaving rats anticipates fluctuations in the sleep-waking cycle , J Neurosci 1, 876–886 (1981). 7. J. N

  16. Role Stress Revisited: Job Structuring Antecedents, Work Outcomes, and Moderating Effects of Locus of Control

    Science.gov (United States)

    Conley, Sharon; You, Sukkyung

    2014-01-01

    A previous study examined role stress in relation to work outcomes; in this study, we added job structuring antecedents to a model of role stress and examined the moderating effects of locus of control. Structural equation modeling was used to assess the plausibility of our conceptual model, which specified hypothesized linkages among teachers'…

  17. Epigenetic Regulation of Individual Modules of the immunoglobulin heavy chain locus 3' Regulatory Region.

    Science.gov (United States)

    Birshtein, Barbara K

    2014-01-01

    The Igh locus undergoes an amazing array of DNA rearrangements and modifications during B cell development. During early stages, the variable region gene is constructed from constituent variable (V), diversity (D), and joining (J) segments (VDJ joining). B cells that successfully express an antibody can be activated, leading to somatic hypermutation (SHM) focused on the variable region, and class switch recombination (CSR), which substitutes downstream constant region genes for the originally used Cμ constant region gene. Many investigators, ourselves included, have sought to understand how these processes specifically target the Igh locus and avoid other loci and potential deleterious consequences of malignant transformation. Our laboratory has concentrated on a complex regulatory region (RR) that is located downstream of Cα, the most 3' of the Igh constant region genes. The ~40 kb 3' RR, which is predicted to serve as a downstream major regulator of the Igh locus, contains two distinct segments: an ~28 kb region comprising four enhancers, and an adjacent ~12 kb region containing multiple CTCF and Pax5 binding sites. Analysis of targeted mutations in mice by a number of investigators has concluded that the entire 3' RR enhancer region is essential for SHM and CSR (but not for VDJ joining) and for high levels of expression of multiple isotypes. The CTCF/Pax5 binding region is a candidate for influencing VDJ joining early in B cell development and serving as a potential insulator of the Igh locus. Components of the 3' RR are subject to a variety of epigenetic changes during B cell development, i.e., DNAse I hypersensitivity, histone modifications, and DNA methylation, in association with transcription factor binding. I propose that these changes provide a foundation by which regulatory elements in modules of the 3' RR function by interacting with each other and with target sequences of the Igh locus.

  18. The cytochrome P450 genesis locus: the origin and evolution of animal cytochrome P450s.

    Science.gov (United States)

    Nelson, David R; Goldstone, Jared V; Stegeman, John J

    2013-02-19

    The neighbourhoods of cytochrome P450 (CYP) genes in deuterostome genomes, as well as those of the cnidarians Nematostella vectensis and Acropora digitifera and the placozoan Trichoplax adhaerens were examined to find clues concerning the evolution of CYP genes in animals. CYP genes created by the 2R whole genome duplications in chordates have been identified. Both microsynteny and macrosynteny were used to identify genes that coexisted near CYP genes in the animal ancestor. We show that all 11 CYP clans began in a common gene environment. The evidence implies the existence of a single locus, which we term the 'cytochrome P450 genesis locus', where one progenitor CYP gene duplicated to create a tandem set of genes that were precursors of the 11 animal CYP clans: CYP Clans 2, 3, 4, 7, 19, 20, 26, 46, 51, 74 and mitochondrial. These early CYP genes existed side by side before the origin of cnidarians, possibly with a few additional genes interspersed. The Hox gene cluster, WNT genes, an NK gene cluster and at least one ARF gene were close neighbours to this original CYP locus. According to this evolutionary scenario, the CYP74 clan originated from animals and not from land plants nor from a common ancestor of plants and animals. The CYP7 and CYP19 families that are chordate-specific belong to CYP clans that seem to have originated in the CYP genesis locus as well, even though this requires many gene losses to explain their current distribution. The approach to uncovering the CYP genesis locus overcomes confounding effects because of gene conversion, sequence divergence, gene birth and death, and opens the way to understanding the biodiversity of CYP genes, families and subfamilies, which in animals has been obscured by more than 600 Myr of evolution.

  19. Genetic and environmental influences on the relationship between flow proneness, locus of control and behavioral inhibition.

    Directory of Open Access Journals (Sweden)

    Miriam A Mosing

    Full Text Available Flow is a psychological state of high but subjectively effortless attention that typically occurs during active performance of challenging tasks and is accompanied by a sense of automaticity, high control, low self-awareness, and enjoyment. Flow proneness is associated with traits and behaviors related to low neuroticism such as emotional stability, conscientiousness, active coping, self-esteem and life satisfaction. Little is known about the genetic architecture of flow proneness, behavioral inhibition and locus of control--traits also associated with neuroticism--and their interrelation. Here, we hypothesized that individuals low in behavioral inhibition and with an internal locus of control would be more likely to experience flow and explored the genetic and environmental architecture of the relationship between the three variables. Behavioral inhibition and locus of control was measured in a large population sample of 3,375 full twin pairs and 4,527 single twins, about 26% of whom also scored the flow proneness questionnaire. Findings revealed significant but relatively low correlations between the three traits and moderate heritability estimates of .41, .45, and .30 for flow proneness, behavioral inhibition, and locus of control, respectively, with some indication of non-additive genetic influences. For behavioral inhibition we found significant sex differences in heritability, with females showing a higher estimate including significant non-additive genetic influences, while in males the entire heritability was due to additive genetic variance. We also found a mainly genetically mediated relationship between the three traits, suggesting that individuals who are genetically predisposed to experience flow, show less behavioral inhibition (less anxious and feel that they are in control of their own destiny (internal locus of control. We discuss that some of the genes underlying this relationship may include those influencing the function of

  20. A modified RMCE-compatible Rosa26 locus for the expression of transgenes from exogenous promoters.

    Science.gov (United States)

    Tchorz, Jan S; Suply, Thomas; Ksiazek, Iwona; Giachino, Claudio; Cloëtta, Dimitri; Danzer, Claus-Peter; Doll, Thierry; Isken, Andrea; Lemaistre, Marianne; Taylor, Verdon; Bettler, Bernhard; Kinzel, Bernd; Mueller, Matthias

    2012-01-01

    Generation of gain-of-function transgenic mice by targeting the Rosa26 locus has been established as an alternative to classical transgenic mice produced by pronuclear microinjection. However, targeting transgenes to the endogenous Rosa26 promoter results in moderate ubiquitous expression and is not suitable for high expression levels. Therefore, we now generated a modified Rosa26 (modRosa26) locus that combines efficient targeted transgenesis using recombinase-mediated cassette exchange (RMCE) by Flipase (Flp-RMCE) or Cre recombinase (Cre-RMCE) with transgene expression from exogenous promoters. We silenced the endogenous Rosa26 promoter and characterized several ubiquitous (pCAG, EF1α and CMV) and tissue-specific (VeCad, αSMA) promoters in the modRosa26 locus in vivo. We demonstrate that the ubiquitous pCAG promoter in the modRosa26 locus now offers high transgene expression. While tissue-specific promoters were all active in their cognate tissues they additionally led to rare ectopic expression. To achieve high expression levels in a tissue-specific manner, we therefore combined Flp-RMCE for rapid ES cell targeting, the pCAG promoter for high transgene levels and Cre/LoxP conditional transgene activation using well-characterized Cre lines. Using this approach we generated a Cre/LoxP-inducible reporter mouse line with high EGFP expression levels that enables cell tracing in live cells. A second reporter line expressing luciferase permits efficient monitoring of Cre activity in live animals. Thus, targeting the modRosa26 locus by RMCE minimizes the effort required to target ES cells and generates a tool for the use exogenous promoters in combination with single-copy transgenes for predictable expression in mice.

  1. Degenerative alterations in noradrenergic neurons of the locus coeruleus in Alzheimer’s disease****

    Institute of Scientific and Technical Information of China (English)

    Lihua Liu; Saiping Luo; Leping Zeng; Weihong Wang; Liming Yuan; Xiaohong Jian

    2013-01-01

    Mice carrying mutant amyloid-β precursor protein and presenilin-1 genes (APP/PS1 double trans-genic mice) have frequently been used in studies of Alzheimer’s disease; however, such studies have focused mainly on hippocampal and cortical changes. The severity of Alzheimer’s disease is known to correlate with the amount of amyloid-βprotein deposition and the number of dead neurons in the locus coeruleus. In the present study, we assigned APP/PS1 double transgenic mice to two groups according to age: young mice (5–6 months old) and aged mice (16–17 months old). Age-matched wild-type mice were used as controls. Immunohistochemistry for tyrosine hydroxylase (a marker of catecholaminergic neurons in the locus coeruleus) revealed that APP/PS1 mice had 23%fewer cel s in the locus coeruleus compared with aged wild-type mice. APP/PS1 mice also had increased numbers of cel bodies of neurons positive for tyrosine hydroxylase, but fewer tyrosine hydroxylase-positive fibers, which were also short, thick and broken. Quantitative analysis using unbiased stereology showed a significant age-related increase in the mean volume of tyrosine hy-droxylase-positive neurons in aged APP/PS1 mice compared with young APP/PS1 mice. Moreover, the mean volume of tyrosine hydroxylase-positive neurons was positively correlated with the total volume of the locus coeruleus. These findings indicate that noradrenergic neurons and fibers in the locus coeruleus are predisposed to degenerative alterations in APP/PS1 double transgenic mice.

  2. The Relationship between Locus of Control and Personal-Emotional Adjustment and Social Adjustment to College Life in Students with and without Learning Disabilities

    Science.gov (United States)

    Estrada, Lisi; Dupoux, Errol; Wolman, Clara

    2006-01-01

    This study investigated the relationship between locus of control and social and personal-emotional adjustment to college life in students with and without learning disabilities (LD). Differences in locus of control in college students with and without LD were also examined. The Adult Nowicki-Strickland Internal/External Locus of Control Scale…

  3. Health locus of control in patients with graves-basedow disease and hashimoto disease and their acceptance of illness.

    Science.gov (United States)

    Basinska, Malgorzata Anna; Andruszkiewicz, Anna

    2012-01-01

    Adaptation to a chronic somatic disease depends on a variety of factors, including belief in health locus of control. Correlation between health locus of control and illness acceptance in patients with Graves-Basedow and Hashimoto diseases as well as correlation between health locus of control, illness acceptance, sex, and age. THREE METHODS WERE APPLIED: Multidimensional Health Locus of Control Scale by K.A. Wallston, B.S. Wallston and R. DeVellis; the Acceptance of Illness Scale by B.J. Felton, T.A. Revenson, and G.A. Hinrichsena; and a personal questionnaire. Two groups were subject to the research: 68 patients with Graves-Basedow disease and 54 patients with Hashimoto disease. Patients with Graves-Basedow disease, women above all, have their health locus of control in other persons (P = 0,001) and are less inclined to accept their illness (P = 0,005) when compared to patients with Hashimoto disease. A statistically significant correlation occurred between the age of patients and external (i.e., in other persons) health locus of control. Beliefs in health locus of control and type of illness in female patient group are predictors of illness acceptance (P = 0,0009).

  4. The effects of risk perception and flight experience on airline pilots' locus of control with regard to safety operation behaviors.

    Science.gov (United States)

    You, Xuqun; Ji, Ming; Han, Haiyan

    2013-08-01

    The primary objective of this paper was to integrate two research traditions, social cognition approach and individual state approach, and to understand the relationships between locus of control (LOC), risk perception, flight time, and safety operation behavior (SOB) among Chinese airline pilots. The study sample consisted of 193 commercial airline pilots from China Southern Airlines Ltd. The results showed that internal locus of control directly affected pilot safety operation behavior. Risk perception seemed to mediate the relationship between locus of control and safety operation behaviors, and total flight time moderated internal locus of control. Thus, locus of control primarily influences safety operation behavior indirectly by affecting risk perception. The total effect of internal locus of control on safety behaviors is larger than that of external locus of control. Furthermore, the safety benefit of flight experience is more pronounced among pilots with high internal loci of control in the early and middle flight building stages. Practical implications for aviation safety and directions for future research are also discussed. Copyright © 2013 Elsevier Ltd. All rights reserved.

  5. Getting to the core of locus of control: Is it an evaluation of the self or the environment?

    Science.gov (United States)

    Johnson, Russell E; Rosen, Christopher C; Chang, Chu-Hsiang Daisy; Lin, Szu-Han Joanna

    2015-09-01

    Responding to criticisms surrounding the structural validity of the higher order core self-evaluations (CSE) construct, in the current study we examined the appropriateness of including locus of control as an indicator of CSE. Drawing from both theoretical and empirical evidence, we argue that locus of control is more heavily influenced by evaluations of the environment compared with the other CSE traits. Using data from 4 samples, we demonstrate that model fit for the higher order CSE construct is better when locus of control is excluded versus included as a trait indicator and that the shared variance between locus of control and CSE is nominal. This does not mean that locus of control is irrelevant for CSE theory though. We propose that evaluations of the environment moderate the relations that CSE has with its outcomes. To test this proposition, we collected data from 4 unique samples that included a mix of student and employee participants, self- and other-ratings, and cross-sectional and longitudinal data. Our results revealed that locus of control moderated relations of CSE with life and job satisfaction, and supervisor-rated job performance. CSE had stronger, positive relations with these outcomes when locus of control is internal versus external. These findings broaden CSE theory by demonstrating one way in which evaluations of the environment interface with evaluations of the self. (PsycINFO Database Record

  6. Relación entre locus de control, ira y rendimiento deportivo en jugadores de tenis de mesa

    Directory of Open Access Journals (Sweden)

    Higinio González-García

    2017-01-01

    Full Text Available Los objetivos de este estudio fueron comprobar la relación entre el locus de control y el rendimiento de- portivo, y conocer la relación entre el locus de control y las variables de ira. La muestra de la investigación se compuso de 58 jugadores federados de tenis de mesa de toda la geografía española. Los participantes completa- ron un cuestionario sociodemográfico ad hoc , la Escala de Locus de Control (ELC y el Inventario de Expresión de la Ira Estado-Rasgo (STAXI-2. Los resultados revela- ron que no había diferencias de medias en los niveles de locus de control externo en función de la división de juego y del tipo de práctica deportiva (profesionales vs amateurs. Por otro lado, se confirmó la relación entre el locus de control externo y la expresión externa de la ira, encontrándose diferencias estadísticamente signifi- cativas entre la expresión externa de la ira y los grupos de locus de control externo alto y bajo. Finalmente, se concluyó que el nivel de rendimiento deportivo no in- terfería en los niveles de locus de control y, por otro lado, se confirma la relación del locus de control exter- no en la expresión externa de la ira de los jugadores de tenis de mesa. Por lo tanto, el locus de control interno se muestra como una variable protectora importante para intervenir con jugadores y entrenadores.

  7. Large-scale chromatin remodeling at the immunoglobulin heavy chain locus: a paradigm for multigene regulation.

    Science.gov (United States)

    Bolland, Daniel J; Wood, Andrew L; Corcoran, Anne E

    2009-01-01

    V(D)J recombination in lymphocytes is the cutting and pasting together of antigen receptor genes in cis to generate the enormous variety of coding sequences required to produce diverse antigen receptor proteins. It is the key role of the adaptive immune response, which must potentially combat millions of different foreign antigens. Most antigen receptor loci have evolved to be extremely large and contain multiple individual V, D and J genes. The immunoglobulin heavy chain (Igh) and immunoglobulin kappa light chain (Igk) loci are the largest multigene loci in the mammalian genome and V(D)J recombination is one of the most complicated genetic processes in the nucleus. The challenge for the appropriate lymphocyte is one of macro-management-to make all of the antigen receptor genes in a particular locus available for recombination at the appropriate developmental time-point. Conversely, these large loci must be kept closed in lymphocytes in which they do not normally recombine, to guard against genomic instability generated by the DNA double strand breaks inherent to the V(D)J recombination process. To manage all of these demanding criteria, V(D)J recombination is regulated at numerous levels. It is restricted to lymphocytes since the Rag genes which control the DNA double-strand break step of recombination are only expressed in these cells. Within the lymphocyte lineage, immunoglobulin recombination is restricted to B-lymphocytes and TCR recombination to T-lymphocytes by regulation of locus accessibility, which occurs at multiple levels. Accessibility of recombination signal sequences (RSSs) flanking individual V, D and J genes at the nucleosomal level is the key micro-management mechanism, which is discussed in greater detail in other chapters. This chapter will explore how the antigen receptor loci are regulated as a whole, focussing on the Igh locus as a paradigm for the mechanisms involved. Numerous recent studies have begun to unravel the complex and

  8. Telomerase Reverse Transcriptase Locus Polymorphisms and Cancer Risk: A Field Synopsis and Meta-Analysis

    Science.gov (United States)

    Verdi, Daunia; Pooley, Karen A.; Landi, Maria T.; Egan, Kathleen M.; Baird, Duncan M.; Prescott, Jennifer; De Vivo, Immaculata; Nitti, Donato

    2012-01-01

    Background Several recent studies have provided evidence that polymorphisms in the telomerase reverse transcriptase (TERT) gene sequence are associated with cancer development, but a comprehensive synopsis is not available. We conducted a systematic review and meta-analysis of the available molecular epidemiology data regarding the association between TERT locus polymorphisms and predisposition to cancer. Methods A systematic review of the English literature was conducted by searching PubMed, Embase, Cancerlit, Google Scholar, and ISI Web of Knowledge databases for studies on associations between TERT locus polymorphisms and cancer risk. Random-effects meta-analysis was performed to pool per-allele odds ratios for TERT locus polymorphisms and risk of cancer, and between-study heterogeneity and potential bias sources (eg, publication and chasing bias) were assessed. Because the TERT locus includes the cleft lip and palate transmembrane 1-like (CLPTM1L) gene, which is in linkage disequilibrium with TERT, CLPTM1L polymorphisms were also analyzed. Cumulative evidence for polymorphisms with statistically significant associations was graded as “strong,” “moderate,” and “weak” according to the Venice criteria. The joint population attributable risk was calculated for polymorphisms with strong evidence of association. Results Eighty-five studies enrolling 490 901 subjects and reporting on 494 allelic contrasts were retrieved. Data were available on 67 TERT locus polymorphisms and 24 tumor types, for a total of 221 unique combinations of polymorphisms and cancer types. Upon meta-analysis, a statistically significant association with the risk of any cancer type was found for 22 polymorphisms. Strong, moderate, and weak cumulative evidence for association with at least one tumor type was demonstrated for 11, 9, and 14 polymorphisms, respectively. For lung cancer, which was the most studied tumor type, the estimated joint population attributable risk for three

  9. A comparison of problem-based and traditional education on nursing students' locus of control and problem-solving skills.

    Science.gov (United States)

    Günüşen, Neslihan Partlak; Serçekuş, Pınar; Edeer, Aylin Durmaz

    2014-06-01

    The purpose of this study is to compare the locus of control and problem-solving skills of nursing students studying with the problem-based learning method with those of nursing students studying with the traditional method. This is a descriptive and comparative study. For data collection, the Problem-Solving Skills Inventory and the Locus of Control Scale were used. The study sample included 680 nursing students. It was determined that the problem-based learning method was more effective in the development of problem-solving skills and internal locus of control than was the traditional method. © 2014 NANDA International.

  10. The Polycomb group proteins bind throughout the INK4A-ARF locus and are disassociated in senescent cells

    DEFF Research Database (Denmark)

    Bracken, Adrian P; Kleine-Kohlbrecher, Daniela; Dietrich, Nikolaj

    2007-01-01

    The p16INK4A and p14ARF proteins, encoded by the INK4A-ARF locus, are key regulators of cellular senescence, yet the mechanisms triggering their up-regulation are not well understood. Here, we show that the ability of the oncogene BMI1 to repress the INK4A-ARF locus requires its direct association....... These results provide a model for how the INK4A-ARF locus is activated and how Polycombs contribute to cancer....

  11. A meta-analysis identifies adolescent idiopathic scoliosis association with LBX1 locus in multiple ethnic groups

    DEFF Research Database (Denmark)

    Londono, Douglas; Kou, Ikuyo; Johnson, Todd A

    2014-01-01

    BACKGROUND: Adolescent idiopathic scoliosis (AIS) is a common rotational deformity of the spine that presents in children worldwide, yet its etiology is poorly understood. Recent genome-wide association studies (GWAS) have identified a few candidate risk loci. One locus near the chromosome 10q24...... the International Consortium for Scoliosis Genetics (ICSG). METHODS: Here, we report the first ICSG study, a meta-analysis of the LBX1 locus in six Asian and three non-Asian cohorts. RESULTS: We find significant evidence for association of this locus with AIS susceptibility in all nine cohorts. Results for seven...

  12. Pengaruh Locus Of Control terhadap Kinerja dan Kepuasan Kerja Internal Auditor dengan Tri Hita Karana sebagai Variabel Moderasi

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    Komang Adi Kurniawan Saputra

    2012-04-01

    Full Text Available Abstract: The Effect of Locus of Control on Performance and Auditor internal Work Satisfaction with Tri Hita Karana Local Culture as Moderating Variable. This study aims to determine the effect of Locus of Control on performance and job satisfaction of internal auditors star hotels in Bali, as well as local culture Tri Hita Karana as a moderation of this influence. There were 62 internal auditors of star hotels involved in this research. The results of this study indicate a significant influence between Locus of Control on performance and job satisfaction of internal auditors with the local culture Tri Hita Karana as a variable moderation.

  13. Hose in Hose, an S locus-linked mutant of Primula vulgaris, is caused by an unstable mutation at the Globosa locus.

    Science.gov (United States)

    Li, Jinhong; Dudas, Brigitta; Webster, Margaret A; Cook, Holly E; Davies, Brendan H; Gilmartin, Philip M

    2010-03-23

    Hose in Hose mutants of primrose and cowslip have been cultivated since the early 17th century and show dominant homeotic conversion of sepals to petals. The phenotype shows variable penetrance and expressivity and is linked to the S locus, which controls floral heteromorphy in Primula species. Here we demonstrate that the homeotic conversion of sepals to petals in Hose in Hose is associated with up-regulation of both Primula B-function MADS box genes PvDef and PvGlo in the first floral whorl. We have defined a restriction fragment length polymorphism associated with PvGlo that cosegregates with the Hose in Hose phenotype and have also identified and characterized a retrotransposon insertion in the PvGlo promoter which is associated with the up-regulated expression of PvGlo. Excision of this retrotransposon, associated with epigenetic changes at the locus, causes reversion toward normal calyces and restores wild-type flower development. These data define the molecular basis of the Hose in Hose mutation and provide an explanation for its long-documented phenotypic instability.

  14. Mapping of the Hor-3 locus encoding D hordein in Barley.

    Science.gov (United States)

    Blake, T K; Ullrich, S E; Nilan, R A

    1982-12-01

    The hordein storage proteins of barley (Hordeum vulgare L.) are of intense interest due to their genetic diversity and prominence and impact on the industrial and agricultural uses of the seed. Two major hordein loci have been previously mapped on chromosome 5 (Hor-1 and Hor-2 encoding the C and B hordeins, respectively). A third major locus, Hor-3, which codes for D hordein, has been located in the centromeric region of chromosome 5, probably on the long arm. Two allelic variants with apparent molecular weights of 83,000 and 91,000 and similar isoelectric points of 8.0 comprise the products of this locus in the barley varieties 'Advance' and 'Triple Awned Lemma'. The D hordein examined is similar in molecular weight and isoelectric point to the high molecular weight (HMW) glutenin proteins encoded by the 1B chromosome of wheat (Triticum aestivum L.).

  15. Locus of single-prime negative priming: the role of perceptual form.

    Science.gov (United States)

    Chao, Hsuan-Fu

    2013-07-01

    Single-prime negative priming refers to the phenomenon in which after a single prime word is briefly presented, repeating it as the probe target results in a delay in responding to the target. The present study investigated the locus of this negative priming effect. Experiment 1 showed that repeating the identity of the prime produced a negative priming effect but merely repeating the response of the prime did not. Experiment 2 showed that the negative priming effect transformed into positive priming when the probe distractor was absent. Experiments 3 and 4 further revealed that single-prime negative priming was observed when the perceptual form was repeated. Taken together, these results suggest that single-prime negative priming involves a perceptual locus.

  16. The tyrosinase-positive oculocutaneous albinism locus maps to chromosome 15q11. 2-q12

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    Ramsay, M.; Colman, M.A.; Stevens, G.; Zwane, E.; Kromberg, J.; Jenkins, T. (South African Institute for Medical Research, Johannesburg (South Africa)); Garral, M.

    1992-10-01

    Tyrosinase-positive oculocutaneous albinism (ty-pos OCA), an autosomal recessive disorder of the melanin biosynthetic pathway, is the most common type of albinism occurring worldwide. In southern African Bantu-speaking negroids it has an overall prevalence of about 1/3,900. Since the basic biochemical defect is unknown, a linkage study with candidate loci, candidate chromosomal regions, and random loci was undertaken. The ty-pos OCA locus was found to be linked to two arbitrary loci, D15S10 and D15S13, in the Prader-Willi/Angelman chromosomal region on chromosome 15q11.2-q12. The pink-eyed dilute locus, p, on mouse chromosome 7, maps close to a region of homology on human chromosome 15q, and we postulate that the ty-pos OCA and p loci are homologous. 43 refs., 2 figs., 1 tab.

  17. Phophoglucomutase first locus polymorphism as revealed by isoelectric focusing in Southern Africa.

    Science.gov (United States)

    Tipler, T D; Dunn, D S; Jenkins, T

    1982-01-01

    Eleven Southern African populations (representing European, Asian and Negroid populations) have been typed for the first locus phosphoglucomutase (PGM1) using isoelectric focusing (pH range 5.0-8.0) in acrylamide gels. The gene frequencies of the four common alleles at this locus in these populations were compared to those found previously in European and Negroid populations. Marked differences in gene frequencies were observed: Negroes have a lower PGM1(2-) compared with Caucasoids due to a lower PGM1(2-) frequency, Indians a relatively high PGM1(2) due to a higher frequency of the PGM1(2+) allele. The Afrikaans and Ashkenazim do not differ appreciably from their European counterparts. The appearances of the rarer PGM1(6) and PGM1(7) alleles on isoelectric focusing are described and some kinetic properties examined. The PGM2(2-1), or 'Atkinson' phenotype, can also be detected with this technique.

  18. A measuring and correcting method about locus errors in robot welding

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    When tubules regularly arranged are welded onto a bobbin by robot, the position and orientation of some tubules may be changed by such factors as thermal deformations and positioning errors etc. Which make it very difficult to weld automatically and continuously by the method of teaching and playing. In this paper, a kind of error measuring system is presented. By which the position and orientation errors of tubules relative to the teaching one can be measured. And, a method to correct the locus errors is also proposed, by which the moving locus planned via teaching points can be corrected in real time according to measured error parameters. So that, just by teaching one, all tubules on a bobbin could be welded automatically.

  19. Burdock, a novel retrotransposon in Drosophila melanogaster, integrates into the coding region of the cut locus.

    Science.gov (United States)

    Ponomarenko, N A; Bannikov, V M; Anashchenko, V A; Tchurikov, N A

    1997-08-11

    The burdock element is known to be the 2.6-kb insertion into the same region of the cut locus in 12 independently obtained ct-lethal mutants. Here we have determined the complete sequences of this insertion and of the hot spot region. It was found that the burdock is a short retrotransposon with long terminal repeats and a single open reading frame (ORF). The polypeptide encoded by the burdock ORF contains two adjacent regions homologous to the gag and pol polyproteins of the gypsy mobile element. The burdock insertion interrupts the short ORF of the cut locus. The target site sequence of the burdock insertions is similar to the Drosophila topoisomerase II cleavage site.

  20. Paramyotonia congenita and hyperkalemic periodic paralysis map to the same sodium-channel gene locus.

    Science.gov (United States)

    Ptacek, L J; Trimmer, J S; Agnew, W S; Roberts, J W; Petajan, J H; Leppert, M

    1991-01-01

    Paramyotonia congenita (PC), an autosomal dominant muscle disease, shares some clinical and electrophysiological similarities with another myotonic muscle disorder, hyperkalemic periodic paralysis (HYPP). However, clinical and electrophysiologic differences allow differentiation of the two disorders. The HYPP locus was recently shown to be linked to a skeletal muscle sodium-channel gene probe. We now report that PC maps to the same locus (LOD score 4.4, theta = 0 at assumed penetrance of .95). These linkage results, coupled with physiological data demonstrating abnormal sodium-channel function in patients with PC, implicate a sodium-channel gene as an important candidate for the site of mutation responsible for PC. Furthermore, this is strong evidence for the hypothesis that PC and HYPP are allelic disorders. PMID:1654742