Lmo4 in the Basolateral Complex of the Amygdala Modulates Fear Learning

Pavlovian fear conditioning is an associative learning paradigm in which mice learn to associate a neutral conditioned stimulus with an aversive unconditioned stimulus. In this study, we demonstrate a novel role for the transcriptional regulator Lmo4 in fear learning. LMO4 is predominantly expressed in pyramidal projection neurons of the basolateral complex of the amygdala (BLC). Mice heterozygous for a genetrap insertion in the Lmo4 locus (Lmo4gt/+), which express 50% less Lmo4 than their wild type (WT) counterparts display enhanced freezing to both the context and the cue in which they received the aversive stimulus. Small-hairpin RNA-mediated knockdown of Lmo4 in the BLC, but not the dentate gyrus region of the hippocampus recapitulated this enhanced conditioning phenotype, suggesting an adult- and brain region-specific role for Lmo4 in fear learning. Immunohistochemical analyses revealed an increase in the number of c-Fos positive puncta in the BLC of Lmo4gt/+ mice in comparison to their WT counterparts after fear conditioning. Lastly, we measured anxiety-like behavior in Lmo4gt/+ mice and in mice with BLC-specific downregulation of Lmo4 using the elevated plus maze, open field, and light/dark box tests. Global or BLC-specific knockdown of Lmo4 did not significantly affect anxiety-like behavior. These results suggest a selective role for LMO4 in the BLC in modulating learned but not unlearned fear

The importance of alternative host plants as reservoirs of the cotton leaf hopper, Amrasca devastans, and its natural enemies

Many agricultural pests can be harboured by alternative host plants but these can also harbour the pests’ natural enemies. We evaluated the capacity of non-cotton plant species (both naturally growing and cultivated) to function as alternative hosts for the cotton leaf hopper Amrasca devastans (Homoptera: Ciccadellidae) and its natural enemies. Forty-eight species harboured A. devastans. Twenty-four species were true breeding hosts, bearing both nymphal and adult A. devastans, the rest were incidental hosts. The crop Ricinus communis and the vegetables Abelmoschus esculentus and Solanum melongena had the highest potential for harbouring A. devastans and carrying it over into the seedling cotton crop. Natural enemies found on true alternative host plants were spiders, predatory insects (Chrysoperla carnea, Coccinellids, Orius spp. and Geocoris spp.) and two species of egg parasitoids (Arescon enocki and Anagrus sp.). Predators were found on 23 species of alternative host plants, especially R. communis. Parasitoids emerged from one crop species (R. communis) and three vegetable species; with 39 % of A. devastans parasitised. We conclude that the presence of alternative host plants provides both advantages and disadvantages to the cotton agro-ecosystem because they are a source of both natural enemy and pest species. To reduce damage by A. devastans, we recommend that weeds that harbour the pest should be removed, that cotton cultivation with R. communis, A. esculentus, and S. melongena should be avoided, that pesticides should be applied sparingly to cultivate alternative host plants and that cotton crops should be sown earlier

Evaluation of Caesalpinia pulcherrima Linn. for anti-inflammatory and antiulcer activities

Objective : To evaluate the ethanolic and aqueous extracts of aerial parts of Caesalpinia pulcherrima (Linn.) Sw. for anti-inflammatory and antiulcer activities. Materials and Methods : Anti-inflammatory action of the ethanolic and aqueous extracts of C. pulcherrima (100 and 200 mg/kg b.w.) (CPE and CPA) were evaluated by cotton pellet granuloma models. Pylorus ligation and aspirin induced ulcer models were employed for evaluating antiulcer activity for both the extracts. Ulcerogenic potential of CP was also evaluated. Result : The ethanolic and aqueous extracts of C. pulcherrima significantly decreased (P<0.01) the granuloma tissue development. CPE and CPA at both the doses exhibited significant (P<0.01) antiulcer activity by decreasing the ulcer score in both the ulcer models and it was not ulcerogenic. Conclusion : The ethanolic and aqueous extracts of aerial parts of C. pulcherrima (CPE and CPA) possess significant anti-inflammatory and antiulcer activities

Preventing unwanted breakups: Using polygalacturonases to regulate cell separation

Cell separation is an important biological process in plants that is precisely regulated both spatially and temporally. Key separation events include abscission of organs such as leaves and fruit and dehiscence events such as pod shatter in canola and other Brassicas. Polygalacturonases (PGs) are enzymes essential for the degradation of pectin, an important component of the adhesive material between cells. Although there are around 70 PG genes with overlapping expression domains, recent analysis has revealed the function of several PGs in specific aspects of Arabidopsis reproductive development. Upstream regulators that control the expression domain of some of these PGs during reproductive development have also been identified. This information provides new strategies to control unwanted cell separation events in various crops