1,008 research outputs found

    Altered functional properties of the codling moth Orco mutagenized in the intracellular loop-3

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    Amino acid substitutions within the conserved polypeptide sequence of the insect olfactory receptor co-receptor (Orco) have been demonstrated to influence its pharmacological properties. By sequence analysis and phylogenetic investigation, in the Lepidopteran subgroup Ditrysia we identified a fixed substitution in the intracellular loop-3 (ICL-3) of a conserved histidine to glutamine. By means of HEK293 cells as a heterologous system, we functionally expressed Orco from the Ditrysian model Cydia pomonella (CpomOrco) and compared its functional properties with a site-directed mutagenized version where this ICL-3-glutamine was reverted to histidine (CpomOrco(Q417H)). The mutagenized CpomOrco(Q417H) displayed decreased responsiveness to VUAA1 and reduced response efficacy to an odorant agonist was observed, when co-transfected with the respective OR subunit. Evidence of reduced responsiveness and sensitivity to ligands for the mutagenized Orco suggest the fixed glutamine substitution to be optimized for functionality of the cation channel within Ditrysia. In addition, contrary to the wild type, the mutagenized CpomOrco(Q417H) preserved characteristics of VUAA-binding when physiologic conditions turned to acidic. Taken together, our findings provide further evidence of the importance of ICL-3 in forming basic functional properties of insect Orco- and Orco/OR-channels, and suggest involvement of ICL-3 in the potential functional adaptation of Ditrysian Orcos to acidified extra-/intracellular environment

    Bioinformatic identification of a putative microRNA-transcription factor network motif in the regulation of laccase genes in peach (Prunus persica)

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    Laccase proteins are multicopper glycoprotein oxidases expressed in plant tissues under biotic and abiotic stress conditions. They are able to catalyze oxidation of a broad range of substrates including phenols and amines. The regulation of expression of such genes is crucial for proper reaction to stress. At the DNA level, this modulation is mediated by the recruitment of specific transcription factors (TF) to suitable transcription factor binding sites (TFBS), usually located upstream of a gene. At the RNA level, the short microRNAs molecules (miRs) interfere with the translation of target proteins through base‐pairing with messenger RNAs. Complex regulatory circuits combining those interactions fine‐tune protein expression and enhance plant responses to environmental change. In this case study we performed a phylogenetic analysis of peach laccases and characterized specific peach miRs (miR397a and miR408), reported previously as posttranscriptional regulatory elemen ts of laccase genes. Using a bioinformatic approach we identified unique TFBS for abscisic acid (ABA) response elements in promoter regions of both miR and laccase genes. The signaling molecule ABA plays a major role in plant responses to stress. We propose a feed‐forward loop motif in the stress response network involving ABA action in peach by integrating the TF‐mediated regulation of miR and laccase genes at the transcriptional level with the miR regulation of laccase target genes at the post‐transcriptional level

    Comparative transcriptomic assessment of the chemosensory receptor repertoire of Drosophila suzukii adult and larval olfactory organs

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    The spotted wing Drosophila, Drosophila suzukii, has emerged within the past decade as an invasive species on a global scale, and is one of the most economically important pests in fruit and berry production in Europe and North America. Insect ecology, to a strong degree, depends on the chemosensory modalities of smell and taste. Extensive research on the sensory receptors of the olfactory and gustatory systems in Drosophila melanogaster provide an excellent frame of reference to better understand the fundamentals of the chemosensory systems of D. suzukii. This knowledge may enhance the development of semiochemicals for sustainable management of D. suzukii, which is urgently needed. Here, using a transcriptomic approach we report the chemosensory receptor expression profiles in D. suzukii female and male antennae, and for the first time, in larval heads including the dorsal organ that houses larval olfactory sensory neurons. In D. suzukii adults, we generally observed a lack of sexually dimorphic expression levels in male and female antennae. While there was generally conservation of antennal expression of odorant and ionotropic receptor orthologues for D. melanogaster and D. suzukii, gustatory receptors showed more distinct species-specific profiles. In larval head tissues, for all three receptor gene fam-ilies, there was also a greater degree of species-specific gene expression patterns. Analysis of chemosensory re-ceptor repertoires in the pest species, D. suzukii relative to those of the genetic model D. melanogaster enables comparative studies of the chemosensory, physiology, and ecology of D. suzukii

    “Development and validation of the ICAP Technology Scale to measure how teachers integrate technology into learning activities”

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    Previous research investigating the use of technology in school has focused mainly on the frequency of use of digital tools during lessons rather than investigating how technology is integrated with respect to different kinds of learning activities. Since the impact of technology use on learning depends on how it is used and on what activities supported by technology are implemented in lessons, a measurement instrument assessing how technology is integrated into learning activities is necessary to investigate its impact on teaching and learning processes. According to the interactive, constructive, active, and passive (ICAP) framework, which distinguishes four different learning activities based on the level of students' cognitive engagement, we developed the 12-item ICAP Technology Scale (ICAP-TS) that accounts for all four dimensions of technology integration in lessons. We used confirmatory factor analysis to validate the four-factor structure of the ICAP-TS with a sample of 1059 upper-secondary school teachers from Switzerland. We also examined reliability using classical test theory and Rasch model analysis to assess the scale's psychometric characteristics. We then analyzed the associations between the ICAP-TS and a general use frequency measure of 12 educational technologies to test the criterion validity. The results confirmed the four-factor structure of the ICAP-TS and revealed good instrument accuracy. The most difficult items to endorse are those describing the integration of technology into interactive learning activities. Furthermore, all 12 items significantly correlated with the frequency of use of 12 educational technologies. We recommend the ICAP-TS as a short and reliable measurement scale for assessing how technology is integrated into lessons, considering different learning activities based on the ICAP theoretical model

    Chemosensory Receptors in the Larval Maxilla of Papilio hospiton

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    Among the butterflies of the genus Papilio (Lepidoptera: Papilionidae), Papilio hospiton (Gene) has a geographical distribution limited to the Mediterranean islands of Sardinia (Italy) and Corsica (France). This is mainly due to the host range that includes only a few plant species of Apiaceae and Rutaceae growing on these islands. In a previous electrophysiological investigation conducted on the maxillary gustatory system of larvae of P. hospiton and its closely phylogenetically related species Papilio machaon, a significantly higher spike activity was shown for the gustatory neurons of lateral and medial styloconic sensilla in P. hospiton when bitter compounds were tested. This effect was possibly correlated to the limited host choice range for P. hospiton. To shed light on the molecular aspects of this phenomenon, we investigated the expression pattern of sensory-related sequences by conducting a transcriptomic analysis from total RNA isolates of P. hospiton larval maxillae. We identified several transcripts that may be involved in taste (one gustatory receptor, one divergent ionotropic receptor, and several transient receptor potential channels, TRPs) as well as transcripts supporting an olfactory function for this appendage, including odorant receptors (ORs), antennal ionotropic receptors (A-IRs), sensory neuron membrane proteins (SNMPs), and odorant-binding proteins (OBPs). We used Human Embryonic Kidney (HEK293A) cells to heterologously express two of the identified receptors, PhospOR1 and PhospPain, together with their orthologs from P. machaon, for functional characterization. While our data suggest no activation of these two receptors by the ligands known so far to activate the electrophysiological response in larval maxillary neurons of Papilio species, nor temperature activation of both Papilio TRPA-channel Painless, they represent the first attempt in connecting neuronal activity with their molecular bases to unravel diet specialization between closely related Papilio species

    Chemosensory Receptors in the Larval Maxilla of Papilio hospiton

    Get PDF
    Among the butterflies of the genus Papilio (Lepidoptera: Papilionidae), Papilio hospiton (Géné) has a geographical distribution limited to the Mediterranean islands of Sardinia (Italy) and Corsica (France). This is mainly due to the host range that includes only a few plant species of Apiaceae and Rutaceae growing on these islands. In a previous electrophysiological investigation conducted on the maxillary gustatory system of larvae of P. hospiton and its closely phylogenetically related species Papilio machaon, a significantly higher spike activity was shown for the gustatory neurons of lateral and medial styloconic sensilla in P. hospiton when bitter compounds were tested. This effect was possibly correlated to the limited host choice range for P. hospiton. To shed light on the molecular aspects of this phenomenon, we investigated the expression pattern of sensory-related sequences by conducting a transcriptomic analysis from total RNA isolates of P. hospiton larval maxillae. We identified several transcripts that may be involved in taste (one gustatory receptor, one divergent ionotropic receptor, and several transient receptor potential channels, TRPs) as well as transcripts supporting an olfactory function for this appendage, including odorant receptors (ORs), antennal ionotropic receptors (A-IRs), sensory neuron membrane proteins (SNMPs), and odorant-binding proteins (OBPs). We used Human Embryonic Kidney (HEK293A) cells to heterologously express two of the identified receptors, PhospOR1 and PhospPain, together with their orthologs from P. machaon, for functional characterization. While our data suggest no activation of these two receptors by the ligands known so far to activate the electrophysiological response in larval maxillary neurons of Papilio species, nor temperature activation of both Papilio TRPA-channel Painless, they represent the first attempt in connecting neuronal activity with their molecular bases to unravel diet specialization between closely related Papilio species

    Las Primeras Jornadas de Psicología Laboral (1985) en Argentina

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    En este trabajo se presenta un análisis bibliométrico sobre las Primeras Jornadas de Psicología Laboral, realizadas los días 26 y 27 de abril de 1985, en Buenos Aires, Argentina. En el desarrollo se destaca el contexto de organización de las jornadas, las temáticas abordadas y el análisis bibliográfico de los trabajos publicados. Con este trabajo se estima contribuir al reconocimiento histórico del área de especialización y profesionalización de la psicología laboral en Argentina.Fil: Bonantini, Carlos Alberto. Universidad Nacional de Rosario. Facultad de Psicologia; Argentina. Comision Nacional de Investigacion Cientifica y Tecnologica; ArgentinaFil: Gallegos de San Vicente, Miguel Omar. Universidad Nacional de Rosario. Facultad de Psicologia; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto Rosario de Investigaciones en Ciencias de la Educación. Universidad Nacional de Rosario. Instituto Rosario de Investigaciones en Ciencias de la Educación; ArgentinaFil: Quiroga, Victor. Universidad Nacional de Rosario. Facultad de Psicologia; ArgentinaFil: Cattaneo, Maria Romina. Universidad Nacional de Rosario. Facultad de Psicologia; ArgentinaFil: Berra, Martin. Universidad Nacional de Rosario. Facultad de Psicologia; Argentin

    Heterologous expression and functional characterization of Drosophila suzukii OR69a transcript variants unveiled response to kairomones and to a candidate pheromone

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    Drosophila suzukii is a main pest of berries on all continents. Population control relies on insecticides and a current research challenge is to develop alternative strategies. Methods based on behavior-modifying semiochemicals are widely used against other horticultural insects, and the functional characterization of chemoreceptors facilitates the identification of active compounds. Following heterologous expression of single olfactory receptors (ORs) in ab3A olfactory sensory neurons of D. melanogaster, we screened three transcript variants from the OR69a-locus (DsuzOR69aA, DsuzOR69aB, DsuzOR69aC), demonstrating binding to two possible kairomones (3-octanol and R-carvone) and to a possible fly-emitted volatile compound [(Z)-4-nonenal], although with different pharmacological qualities. By coupling Gas Chromatography to SSR (GC-SSR), these ligands enhanced ab3A-spiking at nanogram-aliquots in a complementary fashion among the different OR69a-variants, and we identified another possible kairomone, methyl salicylate, as the most active and specific ligand for the sole DsuzOR69aB. In testing headspaces collected from D. suzukii females and from the fly-associated yeast Hanseniaspora uvarum we did not observe activation from female headspaces but activation from yeast headspaces. In situ hybridization analysis on D. suzukii antennae suggests unique expression of OR69a-subunits in specific neurons, and points toward co-expression within the same neurons. The OR69a-subunits of D. suzukii constitute cation channels, which binding suggests kairomone specificity, even if effects coexist for a complementary binding of (Z)-4-nonenal. Methyl salicylate is the most active ligand and is specific to the sole DsuzOR69aB, inspiring future investigation to validate potentials of this compound for D. suzukii control strategies

    Swine cortical and cancellous bone: histomorphometric and densitometric characterisation

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    Introduction: Swine bone morphology, composition and remodelling are similar to humans’, therefore they are considered good models in bone-related research. They have been used for several studies involving bone growth, bone and cartilage fractures and femoral head osteonecrosis. Nevertheless, the literature about pig normal bone features is incomplete. This work aims to fill the literature gaps on the microarchitecture and Bone Mineral Density (BMD) of swine femoral diaphysis and distal epiphysis and tibial plateau and diaphysis.Materials and methods: Five hind limbs were collected from slaughtered 80-100 kg pigs. Microscopic analysis of cortical and cancellous bone from middle/distal femur and proximal/middle tibia was performed to determine basic histomorphometric parameters at different sites. Dual-energy X-Rays Absorptiometry was also employed to evaluate BMD. ANOVA and correlation between BMD, bone area (BA) and cortical thickness were performed.Results and discussion: Diaphyseal cortical bone was mostly plexiform both in the tibia and the femur; primary/secondary osteons without clear organization were also found. Mean values for bone area, bone perimeter, trabecular width, number and separation and BMD at different anatomical sites were defined. No significant difference was found for these values at different anatomical sites. BMD proved to be positively correlated with cortical thickness (r=0,80; p<0,01). Despite the small sample size, these results seem homogeneous. They could therefore represent reference values for normal bone parameters in pigs. Applied anatomy and regenerative medicine, in fact, demand very precise information about bone micromorphology, composition and density to provide reliable indication in bone substitutes building. Moreover, since the interpretation of bone abnormalities is based on mastering normal bone characteristics, the definition of reference parameters is mandatory to avoid misinterpretation and allow comparative evaluation.Conclusion: The results of this study, although preliminary, may be considered a dependable starting point for the definition of normal bone features in pigs
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