Project description:This project aims to establish new diagnostic methods for potentially invasive beetle species, which can occur within plant health controls
Project description:Epigenetic mechanisms, such as CpG DNA methylation enable phenotypic plasticity and rapid adaptation to changing environments. CpG DNA methylation is established by DNA methyltransferases (DNMTs), which are well conserved across vertebrates and invertebrates. There are insects with functional DNA methylation despite lacking a complete set of Dnmts. But at least one of the enzymes, DNMT1, appears to be required to maintain an active DNA methylation system. The red flour beetle, Tribolium castaneum, lacks Dnmt3 but possesses Dnmt1 and it has been controversial whether it has a functional DNA methylation system. Using whole genome bisulfite sequencing, we did not find any defined patterns of CpG DNA methylation in embryos. Nevertheless, we found Dnmt1 expressed throughout the entire life cycle of the beetle, with mRNA transcripts significantly more abundant in eggs and ovaries. A maternal knockdown of Dnmt1 caused a developmental arrest in offspring embryos. We show that Dnmt1 plays an essential role in T. castaneum embryos and that its downregulation leads to an early developmental arrest. This function appears to be unrelated to DNA methylation, since we did not find any evidence for this modification. This strongly suggests an alternative role of this protein.
2018-11-14 | GSE120735 | GEO
Project description:Transcriptome assembly of convergent lady beetle, Hippodamia convergent
| PRJNA753921 | ENA
Project description:Genomic distinctness despite shared color patterns among threatened populations of a tiger beetle
Project description:The venom apparatus is a conserved organ in parasitoid wasps that shows adaptations correlated with life-style diversification. Recent venom analyses from selected species reveal considerable complexity and high diversity in venom composition existing not only between closely related species but even between strains and individuals, which may partly determine the potential for parasitoid adaptation. However, the investigations have paid little attention to secondary venom components that also have significant functions in parasitism, and the data in regard to full and accurate quantity of venom compositions at the protein level is not available. Using a combination of transcriptomic and label-free quantitative proteomic, we here explored the venom components of the endoparasitoid Tetrastichus brontispae (Eulophidae), a species devoid of polydnavirus, and provided an in-depth comparison of the venom proteomes between its two closely related strains, Tb-On and Tb-Bl. Results showed that approximately 1505 venom proteins were identified in the venom apparatus of T. brontispae, consistent with the classical venom protein characteristics, including enzymes, protease inhibitors, binding proteins and some immune related proteins. The venom extracts also contained novel venom proteins, such as kynurenine-oxoglutarate transaminase, 4-coumarate CoA ligase and venom protein r-like protein. Comparative venom proteomes revealed that significant quantitative and qualitative changes in venom composition occurred when Tb-Bl strain, with an invasive beetle Brontispae longissima pupa as its habitual host, was exposed to another invasive beetle Octodonta nipae pupa as host consecutively for two years; although the most abundant venom proteins were shared between them. These significantly differentially expressed proteins were mainly enriched in fatty acid biosynthesis and melanotic encapsulation response by enrichment analyses. Furthermore, most of the significantly enriched proteins presented strikingly increased levels or were exclusively identified in the Tb-On strain. These combined results indicated that virulence factors in Tb-On strain might be linked to lipid metabolism or more venom is required to inhibit O. nipae pupa’s melanotic encapsulation upon its parasitism. Altogether, our data reveal that venom composition can quickly evolve and respond to host selection, mainly through rapid changes in regulation of protein abundance and/or the emergence of multigenic families by gene duplication. Our data additionally provide invaluable data for further functional analysis of parasitoid venoms.