Project description:Drosophila larvae and adults possess a potent innate immune response, but the response of their eggs is particularly poor. Here we show that eggs of the beetle Tribolium castaneum, in contrast, possess a full range of immune defence mechanisms, based on complete transcriptome comparisons of naïve, sterilely injured, and bacterially challenged eggs. Upon infection, we find massive upregulation of AMPs and differential regulation of 375 other genes including both IMD and Toll signalling components. Importantly, we show that this extensive response depends on the serosa, an extraembryonic epithelium enveloping yolk and embryo. When we delete the serosa using Tc-zen1 RNAi, none of the AMPs and merely 57 other genes are differentially regulated upon infection. Furthermore, unchallenged eggs reveal serosa-biased expression of several bacterial recognition genes. Thus, the serosa is an immune competent frontier epithelium, and its loss in higher flies might account for the poor immune response of Drosophila eggs. Three different types of eggs were analysed. Wildtype eggs, eggs of which the mother was injected with a control dsRNA, and eggs without a serosa of which the mothers were injected with Tc-zen1 dsRNA. These three egg-types were subjected to three treatments, untreated (naïve), pricked with a sterile needle (sterile injury) and pricked with a mix of E.coli and M.luteus. This resulted in 9 samples which were all collected three times resulting in a total of 27 samples.
Project description:Drosophila larvae and adults possess a potent innate immune response, but the response of their eggs is particularly poor. Here we show that eggs of the beetle Tribolium castaneum, in contrast, possess a full range of immune defence mechanisms, based on complete transcriptome comparisons of naïve, sterilely injured, and bacterially challenged eggs. Upon infection, we find massive upregulation of AMPs and differential regulation of 375 other genes including both IMD and Toll signalling components. Importantly, we show that this extensive response depends on the serosa, an extraembryonic epithelium enveloping yolk and embryo. When we delete the serosa using Tc-zen1 RNAi, none of the AMPs and merely 57 other genes are differentially regulated upon infection. Furthermore, unchallenged eggs reveal serosa-biased expression of several bacterial recognition genes. Thus, the serosa is an immune competent frontier epithelium, and its loss in higher flies might account for the poor immune response of Drosophila eggs.
Project description:The unparalleled success of the insects comprising more than a million species has long stood out to evolutionary biologists. A much overlooked evolutionary innovation of the insects is the serosa, an extraembryonic epithelium that covers yolk and embryo in their eggs. We have shown that this epithelium provides innate immune protection to eggs of the beetle Tribolium castaneum. It remained elusive, however, if this innate immune competence evolved in the Tribolium lineage, or is ancestral to all insects. Here, we expand our studies to the bug Oncopeltus fasciatus that belongs to the basal main group of insects, the Hemimetabola. RNA sequencing reveals an extensive transcriptional response upon infection of the egg with Gram-positive and Gram-negative bacteria. We demonstrate the antimicrobial activity of upregulated peptides using in vitro bacterial growth inhibition assays, and describe two novel families of AMPs called Serosins and Ovicins. By qPCR, we determine that eggs become immune responsive when the serosa develops. Finally, in situ hybridizations show that transcripts of upregulated peptides are located in the serosal cells and not in the underlying embryo. We conclude that the serosa protects the O. fasciatus embryo against pathogens. This first evidence from hemimetabolous insect eggs suggests that immune competence is an ancestral property of the serosa. The evolutionary origin of the serosa with its immune function might have been one of the factors that facilitated the spectacular success of the insects.
Project description:Microbial diversity and composition on the surface of Chinese alligator eggs with different phenotypes during artificial incubation
| PRJNA1250796 | ENA
Project description:Metagenomic binning
| PRJNA1021009 | ENA
Project description:Horizontal transmission of bacterial symbionts from Lagria villosa to plants
Project description:Loss of MOS in female mice disrupts metaphase II arrest, potentially causing infertility and germ cell tumors. Single-egg RNA sequencing revealed widespread gene expression changes in mos -/- eggs, including upregulation of cell cycle regulators like Aurka, Bub3, and Cdk7. Pathways related to RNA metabolism, transcription, and neddylation were also enriched in mos -/- eggs. Notably, the transcriptome of mos -/- eggs differed from that of chemically activated eggs. These results highlight MOS as a key regulator of the meiotic cell cycle and transcriptome integrity essential for oocyte developmental competence.