Project description:A laboratory colony of Phlebotomus perniciosus sand flies was maintained. Sand flies were infected with cultured Leishmania infantum promastigotes in stationary phase. Ten infected sand flies were dissected after 5 days and promastigotes within the gut pooled. The cells were immediately washed in PBS once and lysed in TRIzol reagent (Life Technologies). RNA isolation was completed according to the manufacturer's instructions, obtaining 63ng. RNA-seq libraries were generated using the spliced leader sequence for second strand synthesis (Cuypers et al., 2017; Haydock et al., 2015), thus allowing for specific amplification of sequences from L. infantum promastigotes, thus avoiding contamination with material from the sand fly gut. Single-end sequencing was performed in an Illumina HiSeq2500 instrument and data analysis was conducted using bowtie2, samtools, featureCounts and Geneious. The main findings are: i) substantial differences in differential gene expression between sand fly-derived (sfPro) and cultured (acPro) promastigotes; and ii) over-expression of genes involved in metacyclogenesis in sfPro vs. acPro, including gp63 genes, autophagy genes, etc.
Project description:Microsporidia have attracted much attention because they infect a variety of species ranging from protists to mammals, including immunocompromised patients with AIDS or cancer. Aside from the study on Nosema ceranae, few works have focused on elucidating the mechanism in host response to microsporidia infection. Nosema bombycis is a pathogen of silkworm pM-CM-)brine that causes great economic losses to the silkworm industry. Detailed understanding of the host (Bombyx mori) response to infection by N. bombycis is helpful for prevention of this disease. The 23 K silkworm genome array was used to investigate host responses (i.e., Bombyx mori) occurring at 2, 4, 6 and 8 d post-infection by Nosema bombycis.We focused on elucidating the mechanism of the host response to microsporidia infection, especially for the investigation of host immune response . The third instar molted silkworm larvae were in oral infected by Nosema bombycis. In order to known the silkworm host response to Nosema bombycis infection at different time points, samples of infected larvae (i.e., the treatment set) and uninfected larvae (i.e., the control set) were collected at 2, 4, 6 and 8 dpi for RNA extraction and array hybridization. The obtained data were usd to investigate on the interplay of the genome-wide expression profile of hosts.
Project description:Silkworms show a reproductive behavior induced by sex pheromone. To elucidate the neral mechanism of sex pheromone induced sexual behavior in the silkworm, we attempted to use the neural activity-induced gene as a neural activity marker. Since no neural activity-induced gene was identified in the silkworm, we conducted screening of neural activity-induced gene using the male silkworm brain. By the screening, we identified Bhr38 as a novel neural activity-induced gene, and succeded to comprehensively map the active neruons in the silkworm brain in response to the sex pheromone exposure. Further, we found that Dhr38, the Drosophila homologue of Bhr38, also expressed in a neural activity dependent manner. These results strongly suggest that Hr38 is a highly conserved neural activity-induced gene.
Project description:Microsporidia have attracted much attention because they infect a variety of species ranging from protists to mammals, including immunocompromised patients with AIDS or cancer. Aside from the study on Nosema ceranae, few works have focused on elucidating the mechanism in host response to microsporidia infection. Nosema bombycis is a pathogen of silkworm pébrine that causes great economic losses to the silkworm industry. Detailed understanding of the host (Bombyx mori) response to infection by N. bombycis is helpful for prevention of this disease. The 23 K silkworm genome array was used to investigate host responses (i.e., Bombyx mori) occurring at 2, 4, 6 and 8 d post-infection by Nosema bombycis.We focused on elucidating the mechanism of the host response to microsporidia infection, especially for the investigation of host immune response .
Project description:Silkworms show a reproductive behavior induced by sex pheromone. To elucidate the neral mechanism of sex pheromone induced sexual behavior in the silkworm, we attempted to use the neural activity-induced gene as a neural activity marker. Since no neural activity-induced gene was identified in the silkworm, we conducted screening of neural activity-induced gene using the male silkworm brain. By the screening, we identified Bhr38 as a novel neural activity-induced gene, and succeded to comprehensively map the active neruons in the silkworm brain in response to the sex pheromone exposure. Further, we found that Dhr38, the Drosophila homologue of Bhr38, also expressed in a neural activity dependent manner. These results strongly suggest that Hr38 is a highly conserved neural activity-induced gene. The male silkworms were exposed to the female odor for 30 min (group P). Non-treated male silkworms were used as the control group group C. Ten brains were collected for each sample and stored at -80°C until use. Total RNA was isolated by the TRIzol reagent and subjected to microarray experiments using the custam made (8x16k) Oligo Microarray (Agilent Technologies, Inc.).
Project description:Background: MicroRNA (miRNA) and other small regulatory RNAs contribute to the modulation of a large number of cellular processes. We sequenced three total RNA libraries prepared from the whole body, and the anterior and posterior silk glands of Bombyx mori, with a view to expanding the repertoire of silkworm miRNAs and exploring transcriptional differences in miRNAs between segments of the silk gland. Results: With the aid of large-scale Solexa sequencing technology, we validated 244 unique miRNA genes, including 191 novel and 53 previously reported genes, corresponding to 309 loci in the silkworm genome. Interestingly, 24 unique miRNAs were widely conserved from invertebrates to vertebrates; 12 unique ones were limited to invertebrates and 33 were confined to insects; whereas the majority of the newly identified miRNAs were silkworm-specific. We identified 21 clusters and 42 paralogs of miRNAs in the silkworm genome. However, sequence tags showed that paralogs or clusters are not prerequisites for coordinated transcription and accumulation. The majority of silkworm-specific miRNAs are located in transposable elements, and display significant differences in abundance between the anterior and posterior silk glands. Conclusions: Conservative analysis revealed that miRNAs serve as phylogenetic markers and function in evolutionary signaling. The newly identified miRNAs greatly enriched the repertoire of insect miRNAs, and provide insights into miRNA evolution, biogenesis, and expression in insects. The differential expression of miRNAs in the anterior and posterior silk glands supports their involvement as new layers in the regulation of the silkworm silk gland.