Project description:To better understand the underlying mechanism of beta-cell regeneration in adult zebrafish, we performed single-cell transcriptomic profiling of the pancreatic tissue (using 10X Genomics) at various stages post beta-cell ablation.
Project description:To determine the change at the transcriptomic level of ductal cells during beta cell regeneration, we performed RNA-seq on pancreatic ductal cells 3 days after beta cell destruction and compared with non ablated control
Project description:Pancreatic beta-calls are responsible for regulating the blood glucose levels via secretion of hormone insulin. To elucidate the chromatin state in zebrafish beta-cells, we performed ATAC-Sequencing.
Project description:We aimed to understand the functional roles of islet cellular oscillators under diabetic conditions and during β-cell regeneration. We assessed diurnal regulation of β-cell proliferation and the transcriptional landscape in α- and residual β-cells following β-cell ablation in Insulin-rtTA/TET-DTA mice that simultaneously expressed α- and β-cell specific fluorescent reports. The mouse pancreatic islets were isolated over 24-h with 4-h interval, followed by separation of α- and β- cells using FACS sorting, RNA extraction and RNA sequencing. Acute hyperglycemia and loss of β-cell mass perturbed absolute expression levels and temporal transcriptome profiles in residual β-cells, whereas in neighboring α-cells only changes in temporal profiles were observed. Strikingly, compensatory regeneration of β-cells exhibited circadian rhythmicity. In arrhythmic Bmal1 deficient mice, massive β-cell ablation led to aggravated hyperglycemia, hyperglucagonemia and a fatal diabetes. No compensatory proliferation of β-cells was observed in arrhythmic mice, suggesting an essential role of circadian clocks in β-cell regeneration.
Project description:Pathways that stimulate β-cell regeneration remain of great clinical interest, yet effective therapeutic avenues that promote survival or reconstitution of β-cell mass remain elusive. Utilizing a mouse model with inducible β-cell apoptosis followed by adiponectin-mediated regeneration, we aimed to identify key molecules boosting β-cell viability. Within the regenerating pancreatic islets, we examined changes within the transcriptome, and observed an extensive upregulation of genes encoding proteins involved in lipid transport and metabolism. The most prominent targets were further confirmed by quantitative PCR and immunofluorescence. Among the upstream regulators predicted by pathway analysis of the transcriptome, we detected enhanced levels of two key transcription factors, HNF4α and PPARα. Enhanced leptin levels in circulation may also contribute to the anti-lipotoxic program in islets. In summary, our data suggest that improving local lipid metabolism as an important anti-lipotoxic phenomenon to boost β-cell regeneration, primarily mediated by adiponectin’s action on the β-cells directly as well as on the adipocyte. RNA profiles of pancreatic islets isolated from PANIC-ATTAT mice crossed with adiponectin wild-type (P-Adn+/+) or the overexpressing transgene (P-AdnTg/+) at 5 weeks after initial dimerizer administration.
Project description:The process of regeneration by in vivo transdifferentiation in mammals is poorly understood. Here, using pancreatic β cell regeneration as a paradigm, we performed a single-cell transcriptomic study of in vivo transdifferentiation from adult mouse acinar cells to induced β cells.