Project description:Transcriptional profiling of E9.5 mouse embryo tissue from the presomitic mesoderm (PSM) and somites I-IV. Tissue from embryos lacking a functional Paraxis gene (Paraxis-/-) was compared to identical tissue from E9.5 Wild Type embryos. The goal was to identify genes that had become deregulated in the absence of the transcription factor, Paraxis. Two-condition experiment: WT vs Paraxis-/- tissue. Biological replicates: 3 pools of 5 WT samples, 3 pools of 5 Paraxis-/- samples. Technical replicates: 3 dye swaps.
Project description:Presomitic mesoderm (PSM) were microdissected from E9.5 mouse embryos (WT and TCre/+;Taf10flox/flox). 3 PSM (17-19 somites stage) were pooled per microarray, in triplicates, per genotypes
Project description:Transcriptional profiling of E9.5 mouse embryo tissue from the presomitic mesoderm (PSM) and somites I-IV. Tissue from embryos lacking a functional Paraxis gene (Paraxis-/-) was compared to identical tissue from E9.5 Wild Type embryos. The goal was to identify genes that had become deregulated in the absence of the transcription factor, Paraxis.
Project description:Somitogenesis is the segmentation of the developing embryonic body axis into somites and is guided by oscillating genes, which create waves of expression that travel across the presomitic mesoderm (PSM) from posterior to anterior. Upon arrival of a wave at the PSM's anterior end, a new somite is formed. To identify genes that are expressed in a wave-like pattern we dissected the PSM of four different mouse embryos (pre-turned), separated the left and right sides, and divided each into five segments, from posterior to anterior (sampling sites 1 to 5). Each segment was used to construct libraries for high-throughput RNA-sequencing. For one embryo, we also sequenced two somites.
Project description:To examine global gene expression profile of chicken early paraxial mesoderm differentiation, we microdissected stage 12HH chicken PSM regions into 20 pieces (10 pieces both left-right PSM), including the tail bud, the PSM and somites. We create microarray series using these fragments.
Project description:Within a given vertebrate species, the total number of vertebrae in each anatomical domain is precisely defined and shows little variation among individuals. In contrast, this number can vary tremendously between different species, ranging from as few as six vertebrae in frogs to as many as several hundred in some snakes and fish. Segmental precursors of the vertebrae, called somites are produced sequentially in the embryo from the presomitic mesoderm (PSM), until a final number characteristic of the species, is reached. Here, we show in the chicken embryo that, by controlling the rate of axis elongation, Hox genes control the total number of somites generated by the embryo. We observed that activation of the most posterior Hox genes in somite precursors of the tail bud correlates with an abrupt slowing-down of the speed of axis elongation. We show that progressively more posterior Hox genes, which are collinearly activated in somitic precursors of the epiblast, repress Wnt activity with increasing strength. This leads to a graded repression of the Brachyury/T transcription factor, reducing mesoderm ingression and slowing down the elongation process. Due to the continuation of somite formation, the PSM, which is not fed with sufficient supply of new cells posteriorly, becomes progressively exhausted, ultimately leading to an arrest of segment formation. Our data provide a conceptual framework to explain how the cross-talk between the segmentation clock and the Hox clock accounts for the diversity of vertebral formulae across animal species. Primitive streak aera corresponding to PSM precursors were dissected in Stage 9 somites chicken embryo overexpressing HoxA13 or a control H2B-Venus. The experiment was designed to have biological duplicate in each conditions. The gain-of-function was obtained by electroporating the embryo at Stage 5HH with a vector containing HoxA13 under the CAGGS promoter with an H2B venus reporter. In order to have enough material for the microarray, 7 embryos were pooled in each sample before the hybridization.
Project description:Dynamic gene expression in the PSM of vertebrates is critical for the spatial and temporal patterning of somites. Using microarray analysis, we explored in detail, genes that are differentially regulated upon removal of CREB family function from the mouse PSM.
Project description:To examine global gene expression profile of chicken early paraxial mesoderm differentiation, we microdissected stage 12HH chicken PSM regions into 20 pieces (10 pieces both left-right PSM), including the tail bud, the PSM and somites. We create microarray series using these fragments. Duplicated 10 fragmented tissues from stage 12 chicken PSM regions. contributor: IGBMC microarray facility
Project description:We used microarrays to identify Pax3 targets during myogenesis in the mouse embryo Mouse embryos were genotyped Pax3GFP/+ or Pax3PAX3-FKHR/GFP and dissected at E9.5 under a fluorescent binocular. Somites were dissected from the interlimb region and the more hypaxial domain separated from the neural tube and the epaxial extremity of the somites. GFP positive cells were then sorted by flow cytometry before RNA extraction and hybridization on Affymetrix microarrays. We also sorted GFP negative cells.