Project description:Human utilization of the mulberry-silkworm interaction started at least 5,000 years ago and greatly influenced world history through the Silk Road. Complementing the silkworm genome sequence, here we describe the genome of a mulberry species (Morus notabilis C. K. Schneider). In the 330 Mb genome assembly of M. notabilis, we identified 128 Mb of repetitive sequences and 29,338 genes, 60.8% of which were supported by transcriptome sequencing. Mulberry gene sequences appear to evolve ~3 times faster than other Rosales, perhaps facilitating its spread to Europe, Africa, and America. It is among few eudicots but several Rosales not preserving genome duplications in more than 100 million years – however neopolyploid series in mulberry and several others suggest that new duplications may confer benefits. Strikingly, five predicted mulberry miRNAs were found in the hemolymph and silkglands of silkworm, suggesting profound molecular level interactions that promise to expand knowledge of plant-herbivore relationship which constitute key elements of most terrestrial habitats. In addition, we investigated the characters of hemolymph small RNA. small mRNA profiles of silkworm hemolymph in the fifth instar day-5 silkworm were generated by deep sequencing, in twice, using Illumina Hiseq 2000.
Project description:The silkworm, Bombyx mori, is a complete metamorphosis insect and an economically important for silk production, the model to study insect physiology and biochemistry. Bombyx mori nucleopolyhedrovirus (BmNPV) is a principal pathogen of the silkworm and its host range is restricted to silkworm larvae, requiring interaction with silkworm larvae to accomplish virus replication. Prothoracic glands (PGs) are a model for synthetic ecdysone with regulating insect growth and development. In this study, day-4 fifth instar silkworm larvae were infected by BmNPV, the wandering silkworms appeared in the infected groups were 12 hours earlier than that in the control groups, and the ecdysone titer in infected larvae was significantly higher than that of the control larvae. Then, we used RNA sequencing (RNA-seq) to analyze silkworm PGs 48 h after BmNPV infection. The classifications of the 15 differential expression genes (DEGs) were mainly involved in the metabolic processes and pathways. The RT-qPCR results of the DEGs in the PGs of BmNPV-infected at 24, 48, and 72 h were generally consistent with the transcriptome data. The transcripts of BmTrypsin-1 and BmACSS3 were significantly increased from 24 to 72 h after BmNPV infection that they may be involved in the maturation process in the latter half of silkworm fifth instar larvae. These findings will help to address the interactions between BmNPV infection and host developmental response.
Project description:Human utilization of the mulberry-silkworm interaction started at least 5,000 years ago and greatly influenced world history through the Silk Road. Complementing the silkworm genome sequence, here we describe the genome of a mulberry species (Morus notabilis C. K. Schneider). In the 330 Mb genome assembly of M. notabilis, we identified 128 Mb of repetitive sequences and 29,338 genes, 60.8% of which were supported by transcriptome sequencing. Mulberry gene sequences appear to evolve ~3 times faster than other Rosales, perhaps facilitating its spread to Europe, Africa, and America. It is among few eudicots but several Rosales not preserving genome duplications in more than 100 million years – however neopolyploid series in mulberry and several others suggest that new duplications may confer benefits. Strikingly, five predicted mulberry miRNAs were found in the hemolymph and silkglands of silkworm, suggesting profound molecular level interactions that promise to expand knowledge of plant-herbivore relationship which constitute key elements of most terrestrial habitats. In addition, we investigated the characters of hemolymph small RNA.
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:Insect cuticle plays essential roles in multiple physiological functions. During molting and metamorphosis, tremendous changes occur in silkworm cuticles. Silkworm is a model of Lepidoptera insects; however, little is known about the stage expression profiles of genes in cuticles of silkworm. In the present study, we selected 16 developmental stages, ranging from day 1 of the first instar larvae to day 8 of pupae, to perform microarray-based expression profiles. The data told us that various functions and physiological pathways were activated in the cuticle. Moreover, the expression profiles of cuticular protein genes, as the important components of cuticle, were investigated. The current study provides important insights for the functional study of insect cuticle and the regulation of insect cuticular protein genes.
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.