Project description:We sequenced the transcriptome of gentamicin induced renal regeneration in adult zebrafish. Specifically, zebrafish kidney tissues in the first, third, fifth and seventh days of kidney injury and the control group were selected. Each sample contains three kidneys. Three samples were taken in each period, and then the total RNA of the kidney was extracted for second-generation sequencing.
Project description:In previous studies, we identified and demonstrated that a 1.2kb cebpd downstream element (CEN) is capable and neccessary for the induction of cebpd in the kidney after cardiac injury. The goal of this study is to unveal the Cebpd regulated responses of kidney to cardiac regeneration in zebrafish. we profiled responses by kidney in cebpd mutant and enhancer (CEN) mutant fish zebrafish to massive injuries of the heart.
Project description:Ischemic 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. In order to study zebrafish heart regeneration, a time course experiment was realized where amputated heart regenerating were compared to control heart. Samples in triplicate were extracted at 1, 3, 5 and 7 days post-amputation.
Project description:The zebrafish has the capacity to regenerate its heart after severe injury. While the function of a few genes during this process has been studied, we are far from fully understanding how genes interact to coordinate heart regeneration. To enable systematic insights into this phenomenon, we generated and integrated a dynamic co-expression network of heart regeneration in the zebrafish and linked systems-level properties to the underlying molecular events. Across multiple post-injury time points, the network displays topological attributes of biological relevance. We show that regeneration steps are mediated by modules of transcriptionally coordinated genes, and by genes acting as network hubs. We also established direct associations between hubs and validated drivers of heart regeneration with murine and human orthologs. The resulting models and interactive analysis tools are available at http://infused.vital-it.ch. Using a worked example, we demonstrate the usefulness of this unique open resource for hypothesis generation and in silico screening for genes involved in heart regeneration. In order to monitor the whole regeneration process, we recovered samples at different time points post-injury: 4 h, 1 day, 3 days, 7 days, 14 days and 90 days (respectively 4 hpi, 1 dpi, 3 dpi, 7 dpi, 14 dpi and 90 dpi). Cryoinjured hearts were compared to healthy hearts from control fish in 3 independent experiments.
Project description:After heart injury, adult zebrafish can perfectly regenerate its heart without any scar tissue left. We performed 100bp*2, paired-end, strand-specific, polyA-positive RNA-seq on hearts from 2 group of adult zebrafish, in which one was sham group and the other 7 days after heart tip amputation (7dpa). We found pathways involving hydrogen peroxidate related functions significantly up-regulated in 7dpa group, indicating its role in heart regeneration. RNA-seq: hearts from sham or 7dpa adult zebrafish
Project description:Adult zebrafish, in contrast to mammals, are able to regenerate their hearts in response to injury or experimental amputation. Our understanding of the cellular and molecular bases that underlie this process, although fragmentary, has increased significantly over the last years. However, the role of the extracellular matrix (ECM) during zebrafish heart regeneration has been comparatively rarely explored. Here, we set out to characterize the ECM protein composition in adult zebrafish hearts, and whether it changed during the regenerative response. For this purpose, we first established a decellularization protocol of adult zebrafish ventricles that significantly enriched the yield of ECM proteins. We then performed proteomic analyses of decellularized control hearts and at different times of regeneration. Our results show a dynamic change in ECM protein composition, most evident at the earliest (7 days post-amputation) time-point analyzed. Regeneration associated with sharp increases in specific ECM proteins, and with an overall decrease in collagens and cytoskeletal proteins. We finally tested by atomic force microscopy that the changes in ECM composition translated to decreased ECM stiffness. Our cumulative results identify changes in the protein composition and mechanical properties of the zebrafish heart ECM during regeneration.
Project description:Zebrafish spontaneously regenerate the retina after injury. Currently, studies have observed gene expression profiles in this species however this may be a poor reflection of protein function. To further address this and expand our understanding of the regenerative process in the zebrafish, we compared the proteomic profile of the retina during injury and upon regeneration. Ouabain was injected intravitreously to create a model of degeneration and regeneration of the retina which was extracted at 0, 3 and 18 days after injection. Differences in protein expression indicates reduced metabolic processing, and increase in fibrin clot formation, with significant upregulation of fibrinogen gamma polypeptide, apolipoproteins A-Ib and A-II, galectin-1, and vitellogenin-6 during degeneration when compared to normal retina. In addition, cytoskeleton and membrane transport proteins were considerably altered during regeneration, with the highest fold upregulation observed for tubulin beta 2A, histone H2B and brain type fatty acid binding protein. Key proteins identified in this study may play an important role in the regeneration of the zebrafish retina and investigations on the potential regulation of these proteins may support future investigations in this field.
Project description:Background: Adult zebrafish spontaneously regenerate their retinas after damage. Although a number of genes and signaling pathways involved in regeneration have been identified, the extent of mechanisms regulating regeneration is unclear. Small non-coding RNAs, microRNAs (miRNAs), that regulate regeneration of various tissues in lower vertebrates were examined for their potential roles in regulating zebrafish retinal regeneration. Results: To investigate the requirement of miRNAs during zebrafish retinal regeneration, we knocked down the expression of the miRNA-processing enzyme Dicer in retinas prior to light-induced damage. Dicer loss significantly reduced proliferation of Müller glia-derived neuronal progenitor cells during regeneration. To identify individual miRNAs with roles in retina regeneration, we collected retinas at different stages of light damage and performed small RNA high-throughput sequencing. We identified subsets of miRNAs that were differentially expressed during active regeneration but returned to basal levels once regeneration was completed. To validate the roles of differentially expressed miRNAs, we knocked down 6 different miRNAs that were upregulated in expression during regeneration and demonstrated that they have distinct effects on neuronal progenitor cell proliferation and migration during retina regeneration. Conclusions: miRNAs are necessary for retinal regeneration. miRNA expression is dynamic during regeneration. miRNAs function during initiation and progression of retinal regeneration. Identification of miRNAs before, during and after completion of zebrafish retinal regeneration
Project description:Adult zebrafish, in contrast to mammals, are able to regenerate their hearts in response to injury or experimental amputation. Our understanding of the cellular and molecular bases that underlie this process, although fragmentary, has increased significantly over the last years. However, the role of the extracellular matrix (ECM) during zebrafish heartregeneration has been comparatively rarely explored. Here, we set out to characterize theECM protein composition inadult zebrafish hearts, and whether it changed during the regenerative response. For this purpose, we first established a decellularization protocol of adult zebrafish ventricles that significantly enriched the yield of ECM proteins. We then performed proteomic analyses of decellularized control hearts and at different times of regeneration. Our results show a dynamic change in ECM protein composition, most evident at the earliest (7 dayspost-amputation) time-point analyzed. Regeneration associated withsharp increases inspecific ECM proteins, and with an overall decrease in collagens and cytoskeletal proteins. We finally tested by atomic force microscopythat the changes in ECM composition translatedto decreased ECM stiffness. Our cumulative results identify changes in the protein composition and mechanical properties of the zebrafish heart ECM during regeneration.