Project description:Evaluating the risks and benefits of using traditional medicinal plants is of utmost importance for a huge fraction of the human population, in particular in Northern Vietnam. Zebrafish are increasingly used as a simple vertebrate model for testing toxic and physiological effects of compounds, especially on development. Here, we tested 12 ethanolic extracts from popular medicinal plants collected in Northern Vietnam for their effects on zebrafish survival and development during the first 4 days after fertilization. We characterized more in detail their effects on epiboly, hatching, growth, necrosis, body curvature, angiogenesis, skeletal development and mostly increased movement behavior. Finally, we confirm the effect on epiboly caused by the Mahonia bealei extract by staining the actin filaments and show that this extract also inhibits cell migration of mouse embryo fibroblasts. In conclusion, we show that zebrafish early life stages reveal that traditional medicinal plant extracts are able to affect embryo development to various degrees, prompting caution to apply these medications to pregnant women. In addition, we show that an extract causing delay in epiboly also inhibits mammalian cell migration, suggesting that this effect may serve as a preliminary test for identifying extracts that inhibit cancer metastasis.
Project description:We mapped DNA methylation in 580 animal species (535 vertebrates, 45 invertebrates), resulting in 2443 genome-scale, base-resolution DNA methylation profiles of primary tissue samples from various organs. Reference-genome independent analysis of this comprehensive dataset defined a “genomic code” of DNA methylation, which allowed us to predict global and locus-specific DNA methylation from the DNA sequence within and across species. This code appears broadly conserved throughout vertebrate evolution, with two major transitions – once in the first vertebrates and again with the emergence of reptiles. Beyond the central role of species-specific DNA sequence composition, our dataset identified the tissue type and the individual as two main sources of DNA methylation variability within species. Tissue type was the dominant factor in fish, birds, and mammals, while in invertebrates, reptiles, and amphibians both factors were similarly strong. Cross-species comparisons focusing on heart and liver tissues supported a highly conserved role of DNA methylation for tissue type and identity and cross-mapping based promoter methylation analysis revealed divergence at specific genes. In summary, this study establishes a large resource of vertebrate and invertebrate DNA methylomes, it showcases the power of reference-free epigenome analysis in species for which no reference genomes are available, and it contributes an epigenetic perspective to the study of vertebrate evolution.
Project description:Human tracheobronchial epithelial (HTBE) cells are considered to serve as a good correlate of influenza virus infection in the human respiratory tract. ChIP-Seq analysis was used to profile histone acetylation (H3K27ac) in HTBE cells at multiple time points in response to infection with influenza A/California/04/09 (H1N1), A/Wyoming/03/03 (H3N2), and A/Vietnam/1203/04 (H5N1) HALo virus. The Influenza A/Vietnam/1203/04 (H5N1) HALo mutant virus is an attenuated H5N1 virus generated from wild-type Influenza A/Vietnam/1203/04 (H5N1) virus as described in Steel, J., et al. J Virol. 2009 Feb; 83(4):1742-53.
Project description:Differential expression was determined in Calu-3 cells between mock infected and infection with NS1trunc124: A/Vietnam/1203-CIP048_RG4/2004 (H5N1) or WT: A/Vietnam/1203/2004 (H5N1) at different times post infection.
Project description:Pregnane X receptor (PXR) is generally considered the most important sensor of natural and anthropogenic xenobiotics in vertebrates. In Xenopus, however, PXR plays a role in neural development and it is irresponsive to xenobiotics. We report a first broad-spectrum amphibian xenobiotic receptor, which is an ortholog of the mammalian constitutive androstane receptor (CAR). The low basal activity and pronounced responsiveness to activators such as drugs and steroids displayed by the Xenopus CAR resemble PXR, which both trace back to a common ancestor early in the divergence of land vertebrates. The constitutive activity of CAR emerged first in Sauropsida (reptiles and birds) and it is common to all fully terrestrial land vertebrates (Amniota). This activity can be mimicked by humanizing just two amino acids of the Xenopus CAR. These results demonstrate a remarkable plasticity of CAR which enabled its employment as Xenopus xenosensors. They open way to toxicogenomic and bioaugmentation studies in amphibians, a critically endangered taxon of land vertebrates. Taken together, we provide evidence for a much earlier origin of CAR, for its conservation in tetrapods which exceeds that of PXR, and for its remarkable functional plasticity which enabled its role as a PXR-like xenosensor in Amphibia.
Project description:A/Vietnam/1203-CIP048_RG3/2004 (H5N1) is a PB1-F2 deletion in wild type A/Vietnam/1203/2004 (H5N1). The goal of this study was to determine the host response (C57BL/6 mouse model) to the PB1-F2 mutation at a 10^4 PFU dose.