Project description:The aim of the study was to determine the protein composition of cornified claws of the western clawed frog (Xenopus tropicalis) in comparison to clawless toe tips and back skin. Cornified claws develop on toes I, II, III of the hind limbs, which we refer to as hind limb inner (HI) toes. Toes IV, V of the hind limbs, here referred to as hind limb outer (HO) toes lack claws. Proteins were prepared from HI toe tips including claws, HO toe tips and back skin (BSK) of frogs each (F1, F2, F3) and subjected to proteomic analysis.
Project description:We report on the implications of genetic KO versus MO-mediated KD of the mesoderm-specifying Brachyury paralogues in the Western clawed frog Xenopus tropicalis. While both KO and KD embryos fail to activate the same core gene regulatory network, resulting in virtually identical morphological defects, embryos injected with control or target MOs also show a systemic GC content dependent immune response and many off-target splicing defects.
Project description:RNA-seq technology was used to identify differentially localized transcripts from Xenopus laevis and Xenopus tropicalis stage VI oocytes. Besides the discovery of a group of novel animally enriched RNAs, this study revealed a surprisingly low conservation of vegetal RNA localization between the two frog species. mRNA profiles of Xenopus laevis and Xenopus tropicalis animal and vegetal oocyte halves were generated by RNA-seq technology. For Xenopus laevis, animal and vegetal oocyte RNA preparations from two different females were generated in duplicates. For Xenopus tropicalis, animal and vegetal oocyte RNA preparations from two different females were analyzed.
Project description:RNA-seq technology was used to identify differentially localized transcripts from Xenopus laevis and Xenopus tropicalis stage VI oocytes. Besides the discovery of a group of novel animally enriched RNAs, this study revealed a surprisingly low conservation of vegetal RNA localization between the two frog species.
Project description:Dyes used in fabric and leather industry are being released and accumulated into Canadian ecosystems. Recent studies have demonstrated that dyes made of azo compounds significantly increase toxicity in biota, which is explained by their toxic metabolites (e.g., aromatic amines). The metabolites of azo compounds interact with hydrophobic surfaces of cell membranes causing expansion of the membrane which impede normal cellular functions. It has been suggested that this process leads to cell death due to improper ion balance. Currently, it is estimated that between 10 and 15% of azo dyes are released in the environment as effluent. The aim of this study was to evaluate toxicity and gene networks altered by azo compounds in amphibians using ecotoxicogenomic approaches. Larvae of the frog Silurana tropicalis (Western clawed frog) were exposed to sediment contaminated to 887 ppm Disperse Yellow 7 (DY7). Larvae were exposed from Nieuwkoop-Faber developmental stage 12 to 46. Data suggest that the azo dye DY7 induced cellular stress and interfered with androgen biosynthesis in early tadpole development. At exposure completion, RNA was isolated from whole larvae and quality was ascertained using bioanalyzer analysis. A custom Agilent 4 X 44 K microarray for S. tropicalis was used to characterize gene regulatory networks underlying toxicity. This study presents the transcriptional regulatory pathways affected by DY7 in S. tropicalis early development. Embryos were exposed to the DY7 dye during development. There were 4 control groups exposed and 4 treatment groups exposed.
Project description:Dyes used in fabric and leather industry are being released and accumulated into Canadian ecosystems. Recent studies have demonstrated that dyes made of azo compounds significantly increase toxicity in biota, which is explained by their toxic metabolites (e.g., aromatic amines). The metabolites of azo compounds interact with hydrophobic surfaces of cell membranes causing expansion of the membrane which impede normal cellular functions. It has been suggested that this process leads to cell death due to improper ion balance. Currently, it is estimated that between 10 and 15% of azo dyes are released in the environment as effluent. The aim of this study was to evaluate toxicity and gene networks altered by azo compounds in amphibians using ecotoxicogenomic approaches. Larvae of the frog Silurana tropicalis (Western clawed frog) were exposed to sediment contaminated to 887 ppm Disperse Yellow 7 (DY7). Larvae were exposed from Nieuwkoop-Faber developmental stage 12 to 46. Data suggest that the azo dye DY7 induced cellular stress and interfered with androgen biosynthesis in early tadpole development. At exposure completion, RNA was isolated from whole larvae and quality was ascertained using bioanalyzer analysis. A custom Agilent 4 X 44 K microarray for S. tropicalis was used to characterize gene regulatory networks underlying toxicity. This study presents the transcriptional regulatory pathways affected by DY7 in S. tropicalis early development.
Project description:Naphthenic acids (Nas) are carboxylic acids present in crude oil and classfied as emergent pollutants. The mechanisms underlaying the toxicity of such mixtures are unknown. Changes in gene expression are expected to reflect te teratogenenic effects of the exposure to NAs. The objective of these experiments is to determine the changes in the gene expression profile of Silurana (Xenopus) tropicalis embryos due to the exposition to two NA mixtures.