Analysis of epithelial explants injected with the intracellular domain of Notch (ICD) to block the formation of multi-ciliate cells, either alone or along with FoxJ1. FoxJ1 misexpression leads to the induction fo ectopic cilia in Xenopus laevis epithelia. Results show which genes are affected by FoxJ1 during the induction of ectopic cilia.
The forkhead protein Foxj1 specifies node-like cilia in Xenopus and zebrafish embryos.
No sample metadata fields
View SamplesConditional expression of dominant-negative HIF1a in zebrafish cardiomyocytes severely inhibits heart regeneration. To understand more about the mechanism, we performed microarray analysis of wildtype regenerating zebrafish and dnHIF1a regenerating zebrafish to determine which genes are regulated by hypoxia/HIF1a.
Hypoxia induces myocardial regeneration in zebrafish.
Specimen part, Treatment
View SamplesThe BM-derived CD45+/Sca1+ cells are haematopoietic stem/progenitor cells that have the ability to circulate and migrate and engraft to the muscle tissue, and therefore they are of particular interest. Notably, these cells retain their haematopoietic potential, as revealed both by in vitro and in vivo assays; but they also acquire myogenic potential, as shown by their ability to participate in muscle regeneration. Whether, this latter remarkable ability is the result of the reprogramming of the BM-CD45+/Sca1+ cells and the activation of a myogenic molecular program within these cells, remains controversial. This study aims to clarify this aspect of the process, investigating the role of the muscle microenviroment and key myogenic transcription factors.
Bone marrow-derived hematopoietic cells undergo myogenic differentiation following a Pax-7 independent pathway.
No sample metadata fields
View SamplesIschemic cardiopathy is the leading cause of death in the world, for which efficient regenerative therapy is not currently available. In mammals, after a myocardial infarction episode, the damaged myocardium is replaced by scar tissue featuring collagen deposition and tissue remodelling with negligible cardiomyocyte proliferation. Zebrafish, in contrast, display an extensive regenerative capacity as they are able to restore completely lost cardiac tissue after partial ventricular amputation. Due to the lack of genetic lineage tracing evidence, it is not yet clear if new cardiomyocytes arise from existing contractile cells or from an uncharacterised set of progenitors cells. Nonetheless, several genes and molecules have been shown to participate in this process, some of them being cardiomyocyte mitogens in vitro. Though questions as what are the early signals that drive the regenerative response and what is the relative role of each cardiac cell in this process still need to be answered, the zebrafish is emerging as a very valuable tool to understand heart regeneration and devise strategies that may be of potential value to treat human cardiac disease. Here, we performed a genome-wide transcriptome profile analysis focusing on the early time points of zebrafish heart regeneration and compared our results with those of previously published data. Our analyses confirmed the differential expression of several transcripts, and identified additional genes the expression of which is differentially regulated during zebrafish heart regeneration. We validated the microarray data by conventional and/or quantitative RT-PCR. For a subset of these genes, their expression pattern was analyzed by in situ hybridization and shown to be upregulated in the regenerating area of the heart. The specific role of these new transcripts during zebrafish heart regeneration was further investigated ex vivo using primary cultures of zebrafish cardiomyocytes and/or epicardial cells. Our results offer new insights into the biology of heart regeneration in the zebrafish and, together with future experiments in mammals, may be of potential interest for clinical applications.
Transcriptomics approach to investigate zebrafish heart regeneration.
Specimen part, Time
View SamplesThe events regulating human preimplantation development are still largely unknown, due to scarcity of material, ethical and legal limitations, and lack of reliable techniques to faithfully amplify the transcriptome of a single cell. Nonetheless, knowledge in human embryology is gathering renewed interest due to its close relationship with both stem cell biology and epigenetic reprogramming to pluripotency, and their centrality to regenerative medicine. Using carefully timed genome-wide transcript analyses on single oocytes and embryos, the analysis of the data allowed us to uncover a series of successive waves of embryonic transcriptional initiation which start as early as the 2 cell stage. In addition, we identified hierarchical activation of genes involved in the regulation of pluripotency. Finally, we developed HumER, a free database of human preimplantation human development gene expression to serve the scientific community. Importantly, our work links early transcription in the human embryo with the correct execution of the pluripotency program later in development, and paves the way for the identification of factors to improve epigenetic reprogramming.
Waves of early transcriptional activation and pluripotency program initiation during human preimplantation development.
Specimen part, Cell line
View SamplesWe collected tissues from bent cotyledon stage zygotic embryos, proliferating tissue at day 7 and day 14 induction of somatic embryogenesis and mature somatic emrbyos in a wild type (Col-0) and vtc2 (SALK_146824) insertion.
Vitamin C deficiency improves somatic embryo development through distinct gene regulatory networks in Arabidopsis.
No sample metadata fields
View SamplesTotal RNA was extracted from apratoxin A or vehicle treated HT29 cells using the RNeasy Mini Kit (Qiagen). Probe values from CEL files were condensed to probe sets using Rosetta Resolver software. Resolver ANOVA analysis was then performed between groups.
A functional genomics approach to the mode of action of apratoxin A.
No sample metadata fields
View SamplesParthenogenetic stem cells were derived from parthenotes, then differentiated to mesenchymal stem cells. These were further reprogrammed to induced pluripotent stem cells, which were finally differentiated to secondary mesenchymal stem cells.
Accumulation of instability in serial differentiation and reprogramming of parthenogenetic human cells.
Sex, Specimen part
View SamplesWe generated single and double knockouts of AtNHX5 and AtNHX6 in order to invesigate possible functions in Arabidopsis. nhx5/nhx6 exhibited severe growth retardation related to cell size and proliferation, as well as endosomal trafficking perutrbations. The results implicate endosomal NHX antiporters in novel cellular functions. In order to investigate further the possible functions of AtNHX5 and AtNHX6, we compared the transcrptional profiles of single and double AtNHX5 and AtNHX6 knockouts. We looked for changes in gene expression might help us to elucidate the molecular events associated with the apparent requirement of AtNHX5 and AtNHX6 for normal growth and development.
The Arabidopsis intracellular Na+/H+ antiporters NHX5 and NHX6 are endosome associated and necessary for plant growth and development.
Specimen part
View Sampleswe identify several downstream targets that are under control of miR25/93 cluster Overall design: examination of global changes in mRNAs in two different lines
miR-25/93 mediates hypoxia-induced immunosuppression by repressing cGAS.
Specimen part, Cell line, Subject
View Samples