Project description:Enteroendocrine cells are hormonal secreting cells in the gut. However, as they comprise <1% of the total epithelial cell population, studies on their response to stimuli have been limited. Chang-Graham, Danhof, Engevik, and Tomaro-Duchesneau et al (PMID 31029854) developed a model enteroid system to overcome this limitation. By driving expression of NGN3 in human jejunal enteroids, their system allows for analysis of hormonal secretion and transcriptional analysis in response to a stimulus. To further characterize these NGN3 enteroids, we performed RNASeq on these enteroids in the induced or uninduced state.
Project description:The goal of this study was to evaluate the transcriptional response of human enteroids/colonoids on transwells to infections (bacterial and rotavirus). Enteroids/colonoids lines C103, C109, D103, D109, I103, I109, J2 and J11 were plated on transwells coated with Matrigel, differentiated, and inoculated (rotavirus (Ito), bacteria or mock) for 6 or 24 hours. Subsequently, total RNA was isolated and paired-end sequencing was performed.
Project description:The goal of this experiment is to decipher the mechanism of intestinal endocrine / enteroendocrine subtype specification, that is far from being fully understood. To this end, we used single cell genomics in mouse mini-guts. Enteroendocrine cells are derived from endocrine progenitors expressing the transcription factor Ngn3. We took advantage of the Ngn3+/eYFP mouse model -where endocrine progenitors and their descendants can be isolated and sorted by FACS on the basis of the eYFP fluorescence- and established enteroids or mini-guts from the small intestine. Enteroids were dissociated and eYFP+ single cells were directly sorted in 96 wells of the Precise WTA Single Cell Encoding Plate (BD™ Precise WTA Single Cell Kit, BD Genomics). cDNA and libraries were prepared following the BD protocol. Sequencing (paired-end, 2x100b) was performed in a HiSeq 4000 (Illumina). The bioinformatic analysis allowed to identify 8 different groups of enteroendocrine cells with specific signatures.
Project description:Expression of the proendocrine gene neurogenin 3 (Ngn3) is required for the development of pancreatic islets. In order to better characterize the molecular events regulated by Ngn3 during development, we have determined the expression profile of differentiating murine embryonic stem cells (mESCs) uniformly induced to overexpress Ngn3. An ESC line was created that allows for the induction of Ngn3 by adding doxycycline (Dox) to the culture medium. Genome-wide microarray analysis was performed to identify genes regulated by Ngn3 in a variety of both undifferentiated and differentiated conditions. Characterization of pancreatic developmental markers during embryoid body (EB) formation revealed an optimum context for Ngn3 induction. Neuroendocrine genes including neurogenic differentiation 1 (NeuroD1) and single minded 1 (Sim1) were found to be significantly upregulated. Genes regulated by Ngn3 independent of the context were analyzed using systematic gene ontology tools and revealed Notch signaling as the most significantly regulated signaling pathway (p=0.009). This result is consistent with the hypothesis that Ngn3 expression makes the cell competent for Notch signaling to be activated and conversely, more sensitive to Notch signaling inhibition. Indeed, EBs induced to express Ngn3 were significantly more sensitive to gamma-secretase inhibitor-mediated Notch signaling inhibition (p<0.0001). Moreover, we find that Ngn3 induction in differentiating ESCs results in significant increases in insulin, glucagon, and somatostatin transcription. Keywords: Ngn3 induction, embryonic stem cell differentiation
Project description:NGN3 is a transcription factor whose transient expression during pancreatic development is vital for the generation of endocrine pancreatic cells, including beta cells. NGN3 stabilisation has been shown to induce exocrine-to-endocrine cell plasticity in the murine pancreas, making it a viable target for therapies aiming to replenish beta cells after immune-mediated destruction in type 1 diabetes patients. Here, we set out to identify new interactors of NGN3 that could play a role in its post-translational regulation. We transfected HEK293A cells with HA-tagged NGN3 and carried out immunoprecipitation of the HA-tag, followed by analysis of co-immunoprecipitated interactors via LC-MS/MS.
Project description:We report the human intestinal epithelial host transcriptional response to human enteric virus infection using primary human intestinal enteroids cultures as a model system.
Project description:The GeneChip Porcine Genome Array was used to identify the transcriptional response upon either Salmonella typhimurium (ST) or Salmonella choleraesuis (SC) infection in two porcine epithelial cell lines (IPEC-J2, from jejunum and IPI-2I, from ileum) during 2 and 4 hours post infection. The objectives in this study were first, to identify the different response between the epithelial cell lines from different gut regions; second, to study how the Salmonella serotypes used could elicit a different host response; and third, to determine the effect of the time-points on the differentially gene expression.
Project description:The GeneChip Porcine Genome Array was used to identify the transcriptional response upon either Salmonella typhimurium (ST) or Salmonella choleraesuis (SC) infection in two porcine epithelial cell lines (IPEC-J2, from jejunum and IPI-2I, from ileum) during 2 and 4 hours post infection. The objectives in this study were first, to identify the different response between the epithelial cell lines from different gut regions; second, to study how the Salmonella serotypes used could elicit a different host response; and third, to determine the effect of the time-points on the differentially gene expression.
Project description:This experiment used RNA-Seq technology to explore gene expression in mouse Ngn3^GFP/+ [het] FACS sorted pancreatic cells at E15.5 (commited endocrine progenitor cells) and in Ngn3^GFP/GFP [null] at E15.5 (defective endocrine progenitor cells). This experiment is designed to understand the gene expression alteration in the endocrine lineage at different embryonic days. The aim is to understand both Ngn3 dependent and independent gene expression profiles so as to reveal the instructive signals that specfy the collective endocrine islet cell fate or specific islet cell type.