Differential Expression of Genes Related to Innate Immune Responses in Ex Vivo Spinal Cord and Cerebellar Slice Cultures Infected With West Nile Virus

West Nile virus (WNV) infection results in a spectrum of neurological symptoms, ranging from a benign fever to severe WNV neuroinvasive disease with high mortality. Many who recover from WNV neuroinvasive infection present with long-term deficits, including weakness, fatigue, and cognitive problems. While neurons are a main target of WNV, other cell types, especially astrocytes, play an important role in promoting WNV-mediated central nervous system (CNS) damage. Conversely, it has been shown that cultured primary astrocytes secrete high levels of interferons (IFNs) immediately after WNV exposure to protect neighboring astrocytes, as well as neurons. However, how intrinsic responses to WNV in specific cell types and different regions of the brain modify immune protection is not fully understood. Here, we used a mouse ex vivo spinal cord slice culture (SCSC) and cerebellar slice culture (CSC) models to determine the innate immune responses specific to the CNS during WNV infection. Slices were prepared from the spinal cord and cerebellar tissue of 7⁻9-day-old mouse pups. Four-day-old SCSC or CSC were infected with 1 × 10³ or 1 × 10⁵ PFU of WNV, respectively. After 12 h exposure to WNV and 3 days post-infection in normal growth media, the pooled slice cultures were processed for total RNA extraction and for gene expression patterns using mouse Affymetrix arrays. The expression patterns of a number of genes were significantly altered between the mock- and WNV-treated groups, both in the CSCs and SCSCs. However, distinct differences were observed when CSC data were compared with SCSC. CSCs showed robust induction of interferons (IFNs), IFN-stimulated genes (ISGs), and regulatory factors. Some of the antiviral genes related to IFN were upregulated more than 25-fold in CSCs as compared to mock or SCSC. Though SCSCs had twice the number of dysregulated genes, as compared CSCs, they exhibited a much subdued IFN response. In addition, SCSCs showed astrogliosis and upregulation of astrocytic marker genes. In sum, our results suggest that early anti-inflammatory response to WNV infection in CSCs may be due to large population of distinct astrocytic cell types, and lack of those specialized astrocytes in SCSC may make spinal cord cells more susceptible to WNV damage. Further, the understanding of early intrinsic immune response events in WNV-infected ex vivo culture models could help develop potential therapies against WNV

Genomic innovations, transcriptional plasticity and gene loss underlying the evolution and divergence of two highly polyphagous and invasive <i>Helicoverpa</i> pest species

BACKGROUND: Helicoverpa armigera and Helicoverpa zea are major caterpillar pests of Old and New World agriculture, respectively. Both, particularly H. armigera, are extremely polyphagous, and H. armigera has developed resistance to many insecticides. Here we use comparative genomics, transcriptomics and resequencing to elucidate the genetic basis for their properties as pests. RESULTS: We find that, prior to their divergence about 1.5 Mya, the H. armigera/H. zea lineage had accumulated up to more than 100 more members of specific detoxification and digestion gene families and more than 100 extra gustatory receptor genes, compared to other lepidopterans with narrower host ranges. The two genomes remain very similar in gene content and order, but H. armigera is more polymorphic overall, and H. zea has lost several detoxification genes, as well as about 50 gustatory receptor genes. It also lacks certain genes and alleles conferring insecticide resistance found in H. armigera. Non-synonymous sites in the expanded gene families above are rapidly diverging, both between paralogues and between orthologues in the two species. Whole genome transcriptomic analyses of H. armigera larvae show widely divergent responses to different host plants, including responses among many of the duplicated detoxification and digestion genes. CONCLUSIONS: The extreme polyphagy of the two heliothines is associated with extensive amplification and neofunctionalisation of genes involved in host finding and use, coupled with versatile transcriptional responses on different hosts. H. armigera's invasion of the Americas in recent years means that hybridisation could generate populations that are both locally adapted and insecticide resistant

Improved chromosome-level genome assembly of the Glanville fritillary butterfly (Melitaea cinxia) integrating Pacific Biosciences long reads and a high-density linkage map

Background The Glanville fritillary (Melitaea cinxia) butterfly is a model system for metapopulation dynamics research in fragmented landscapes. Here, we provide a chromosome-level assembly of the butterfly's genome produced from Pacific Biosciences sequencing of a pool of males, combined with a linkage map from population crosses. Results The final assembly size of 484 Mb is an increase of 94 Mb on the previously published genome. Estimation of the completeness of the genome with BUSCO indicates that the genome contains 92-94% of the BUSCO genes in complete and single copies. We predicted 14,810 genes using the MAKER pipeline and manually curated 1,232 of these gene models. Conclusions The genome and its annotated gene models are a valuable resource for future comparative genomics, molecular biology, transcriptome, and genetics studies on this species.Peer reviewe

Synthesis, characterization and antimicrobial activities of metal complexes of 2-formyl thymol oxime

665-669 Metal to ligand (1: 2) complexes with molecular formula [M(HL)2]n [HL = anionic form of 2-formyl thymol oxime, M = metal (II) ion] of 2-formyl thymol oxime (H2L) and its manganese, iron, cobalt, nickel, copper and zinc complexes have been prepared and characterized by elemental analysis, magnetic measurements, molar conductivity, IR and UV-Visible spectroscopy. Complexes were tested for antimicrobial activities against Escherichia coli, Pseudomonas putida, P. fluorescense and Bradyrhizobium japonicum and fungal cultures Aspergillus niger, A. flavus, Fusarium oxysporum, and Alternaria alternata. </smarttagtype

Adaptive regulation of digestive serine proteases in the larval midgut of Helicoverpa armigera in response to a plant protease inhibitor

Protease inhibitors (PIs) are direct defenses induced by plants in response to herbivory. PIs reduce herbivore digestive efficiency by inhibiting insects' digestive proteases; in turn insects can adapt to PIs by generally increasing protease levels and/or by inducing the expression of PI-insensitive proteases. Helicoverpa armigera, a highly polyphagous lepidopteran insect pest, is known for its ability to adapt to PIs. To advance our molecular and functional understanding of the regulation of digestive proteases, we performed a comprehensive gene expression experiment of H. armigera exposed to soybean Kunitz trypsin inhibitor (SKTI) using a custom-designed microarray. We observed poor larval growth on the SKTI diet until 24 h, however after 48 h larvae attained comparable weight to that of control diet. Although initially the expression of several trypsins and chymotrypsins increased, eventually the expression of some trypsins decreased, while the number of chymotrypsins and their expression increased in response to SKTI. Some of the diverged serine proteases were also differentially expressed. The expression of serine proteases observed using microarrays were further validated by qRT-PCR at different time points (12, 24, 48, 72 and 96 h) after the start of SKTI ingestion. There were also large changes in transcriptional patterns over time in the control diet. Carbohydrate metabolism and immune defense genes were affected in response to SKTI ingestion. Enzyme assays revealed reduced trypsin-specific activity and increased chymotrypsin-specific activity in response to SKTI. The differential regulation of trypsins and chymotrypsins at the transcript and protein levels accompanying a rebound in growth rate indicates that induction of SKTI-insensitive proteases is an effective strategy of H. armigera in coping with this protease inhibitor in its diet