Project description:Animals have developed extensive mechanisms of response to xenobiotic chemical attacks. Although recent genome surveys have suggested a broad conservation of the chemical defensome across metazoans, global gene expression responses to xenobiotics are not known in most invertebrates. Here, using high density tiling arrays with over 2 million probes, we explored genome-wide gene expression in the tunicate Oikopleura dioica in response to two model xenobiotic chemicals – the carcinogenic polycyclic aromatic hydrocarbon benzo[a]pyrene (BaP) the pharmaceutical compound Clofibrate (Clo). The genotoxic compound BaP induced xenobiotic biotransformation and oxidative stress responsive genes, as in vertebrates. Notable exceptions were genes of the aryl hydrocarbon receptor (AhR) signaling pathway. Clo also affected the expression of many biotransformation genes and markedly repressed genes involved in energy metabolism and muscle contraction pathways. Oikopleura appears to have basic defensome toolkit consisting of phase I, phase II and phase III biotransformation genes.
Project description:Animals have developed extensive mechanisms of response to xenobiotic chemical attacks. Although recent genome surveys have suggested a broad conservation of the chemical defensome across metazoans, global gene expression responses to xenobiotics are not known in most invertebrates. Here, using high density tiling arrays with over 2 million probes, we explored genome-wide gene expression in the tunicate Oikopleura dioica in response to two model xenobiotic chemicals – the carcinogenic polycyclic aromatic hydrocarbon benzo[a]pyrene (BaP) the pharmaceutical compound Clofibrate (Clo). The genotoxic compound BaP induced xenobiotic biotransformation and oxidative stress responsive genes, as in vertebrates. Notable exceptions were genes of the aryl hydrocarbon receptor (AhR) signaling pathway. Clo also affected the expression of many biotransformation genes and markedly repressed genes involved in energy metabolism and muscle contraction pathways. Oikopleura appears to have basic defensome toolkit consisting of phase I, phase II and phase III biotransformation genes. Exposure of about 130 four-days-old animals in 1L seawater in glass beakers. Pooled animals used, no replicates. DMSO Treatments: -Clofibrate (Clo) (Sigma-Aldrich, St. Louis, MO): 1 µM and 5 µM. -Benzo[a]pyrene (BaP (Sigma-Aldrich): 0.2 µM and 1 µM - Controls received 1 ml Dimethyl sulfoxide (DMSO). -The animals kept at room temperature and harvested after 10 hrs and frozen. -Total RNA was isolated from the pooled animals using the RNeasy Mini Kit according to manufacturer’s protocols (QIAGEN, Hilden, Germany). - 5 µg total RNA was converted to dscDNA using SuperScript Double-Stranded cDNA Synthesis Kit (Invitrogen, Carlsbad, CA), and dscDNA samples were submitted for microarray analysis. BaP and Clo treated samples were labeled using Cy3-coupled random nonamers and DMSO controls were labeled using Cy5-coupled random nonamers. Total 4 hybridizations for the 8 samples (single hybridization for each treatment and DMSO control pair), no replicates.
Project description:ChIP-seq was used to generate chromatin state maps, profile binding patterns of key architectural proteins and locate putative enhancer regions in the early development (TB stage) and developing gonads of the marine chrodate Oikopleura dioica.
Project description:The appendicularian, Oikopleura dioica, is a marine or planktonic tunicate that has a swimming tadpole shape through its entire life. For several reasons, this animal possesses advantages as a model organisms: (1) It has a short life cycle (about 5 days at 20℃); (2) Its development is rapid and it completes organogenesis within 10 hour of post-fertilization to form functional body; (3) its morphogenesis and cell linages are well-described; (4) live imaging of embryos by introducing fluorescent protein mRNAs is feasible; (5) RNAi method is available for knockdown of zygotic mRNA as well as maternal mRNAs in the ovary and eggs. (6) It has a compact and sequenced genome of 70 Mb, the smallest ever found in chordate. The number of genes is estimated as approximately 18,000, indicating a high gene density (one gene per 5 kb in the genome). These features make O. dioica a useful organism to study development and genome plasticity in tunicate with short generation time, namely, rapidly evolving chordate lineage. Two stages: egg and larvae, two biological replicates
Project description:ATAC-seq was used to locate putative enhancer regions in the early development (tailbud stage), developing male and female gonads of the marine chrodate Oikopleura dioica.