Project description:Placental gene expression in pregnancies established after the transfer of day 7 blastocysts derived from in vitro (IVP), somatic cell nuclear transfer (SCNT) and in vivo (AI) embryos
| PRJNA168092 | ENA
Project description:Cattle embryo production using Somatic Cell Nuclear Transfer
Project description:Trichostatin A does not correct specific errors of somatic cell nuclear transfer on the transcriptomic level; highlighing the non-random nature of oocyte-mediated reprogramming errors.
Project description:Cloning mammals by somatic cell nuclear transfer (SCNT) is highly inefficient because of aberrant genomic reprogramming. In addition to random reprogramming errors, we hypothesized the presence of specific errors as evidenced by common anomalies among clones. We found that Xist, which normally inactivates one of the two X chromosomes in females, was ectopically expressed from the active X (Xa) chromosome in cloned mouse embryos of both sexes. Deletion of Xist on Xa normalized global gene expression and produced about a 10-fold increase in cloning efficiency. We also identified an Xist-independent mechanism that specifically downregulated a subset of X-linked genes through somatic-type repressive histone blocks. Thus, we have identified nonrandom reprogramming errors in mouse cloning, which provide promising targets for breakthroughs in SCNT cloning technology. Gene expression were measured in mouse in vitro fertilized and somatic cell cloned blastocysts. More than three biological replicates were performed in each group using defferent nuclear donor cells.
Project description:We hypothesized that the relative abundances of host cell transcripts in lymph nodes of animals with malignant catarrhal fever (MCF), compared to healthy controls, may be used to identify pathways that may help to explain the pathogenesis of MCF. Therefore, an abundance of host cell gene expression patterns in lymph nodes of animals with MCF and healthy controls were analyzed by microarray. Indeed, a vast number of genes related to inflammatory processes, lymphocyte activation, cell proliferation and apoptosis were detected at different abundances. However, the IL-2 transcript was eminent among the transcripts, which were, compared to healthy controls, less abundant in animals with MCF. Compared to healthy cattle, bovines with MCF appear to mimic an IL-2 knockout phenotype that has been described in mice. This supports the hypothesis that immunopathogenic events are linked to the pathogenesis of MCF. IL-2-deficiency may play an important role in the process. Keywords: disease state analysis
Project description:With regulatory roles in development, cell proliferation and disease, micro-RNA (miRNA) biology is of great importance and a potential key to novel RNA-based therapeutic regimens. Biochemically based sequencing approaches have provided robust means of uncovering miRNA binding landscapes on transcriptomes of various species. However, a current limitation to the therapeutic potential of miRNA biology in cattle is the lack of validated miRNAs targets. Here, we use cross-linking immunoprecipitation (CLIP) of the Argonaute (AGO) proteins and unambiguous miRNA-target identification through RNA chimeras to define a regulatory map of miRNA interactions in the cow (Bos taurus). The resulting interactome is the deepest reported to date for any species, demonstrating that comprehensive maps can be empirically obtained. We observe that bovine miRNA targeting principles are consistent with those observed in other mammals. Motif and structural analyses define expanded pairing rules with most interactions combining seed-based pairing with distinct, miRNA-specific patterns of auxiliary pairing. Further, miRNA-target chimeras had predictive value in evaluating true regulatory sites of the miR-17 family. Finally, we define miRNA-specific targeting for >5000 mRNAs and determine gene ontologies (GO) for these targets. This confirmed repression of genes important for embryonic development and cell cycle progress by the let-7 family, and repression of those involved in cell cycle arrest by the miR-17 family, but it also suggested a number of unappreciated miRNA functions. Our results provide a significant resource for transcriptomic understanding of bovine miRNA regulation, and demonstrate the power of experimental methods for establishing comprehensive interaction maps.
Project description:Assessment of genome integrity with array CGH of cattle transgenic cell lines produced by homologous recombination and somatic cell cloning