Project description:To identify genome-wide, direct targets of HES1 in human pancreas progenitors, we performed Chromatin immunoprecipitation followed by deep sequencing (ChIP-seq) of endogenous HES1 in the HUES4 PDX1GFP/+ reporter cell line on Day 13 of differentiation from both unsorted bulk populations and FACS-sorted GFP+ cells.
Project description:To better understand the mechanism by which HES1 regulates pancreas development we took advantage of recent developments in directed differentiation of human embryonic stem cells (hESCs) to the pancreatic endocrine lineage via a series of progenitor stages (Figure 1 and (Rezania et al., 2014). Using the iCRISPR platform (González et al., 2014), we introduced indels in the HES1 and NEUROG3 genes, either singly or in combination in iCRISPR H1 cells. Using previously described gRNAs (Zhu et al., 2016) to target exon2 of the NEUROG3 gene and exon2 of the HES1 gene we detected by Sanger and RNA-sequencing a 2 bp insertion and a T insertion, respectively, resulting in premature STOP codons in two/multiple clonal cell lines carrying the introduced mutation and the loss of NEUROG3 by immunostaining We then subjected two or more clonal lines of H1-iCRISPR (wildtype), HES1−/−, NEUROG3−/− and HES1−/−NEUROG3−/− (abbreviated H1N3-dKO or H1−/−N3−/−) to differentiation to β-like cells using a modified version of the protocol from Rezania et al. (2014). Marker analysis showed that all cell lines maintained pluripotency (OCT4+) as hESC and were able to differentiate to FOXA2+ and SOX17+ co-positive definitive endoderm (DE, Day 3), PDX1+ cells at the posterior foregut stage (PF, Day 7), to bipotent progenitors marked by PDX1+ and NKX6-1+ at the Pancreatic Endoderm stage (PE, Day 10), and the Endocrine Precursor stage (EP, Day 13)
Project description:RNA-seq of FACS Sorted E10.5 Pdx1-GFP+ of genotypes wildtype and Hes1-/-. Summary statement The developmental mechanisms that cause ectopic pancreas are poorly understood. We show that aberrant dorsal pancreas morphogenesis in Hes1 mutants leads to ectopic pancreas depending on the pro-endocrine gene Neurog3. Abstract Mutations in Hes1, a target gene of the Notch signalling pathway, lead to ectopic pancreas by a poorly described mechanism. Here we use genetic inactivation of Hes1 combined with lineage tracing in mouse embryos to reveal an endodermal requirement for Hes1 and that most ectopic pancreas tissue is derived from the E8.5 dorsal pancreas primordium. RNA-seq data from sorted E10.5 Pdx1-GFP+ cells from Hes1+/+ and Hes1−/− suggested that upregulation of endocrine lineage genes in Hes1−/− embryos was the major defect in the endoderm and accordingly early pancreas morphogenesis was normalised and the ectopic pancreas phenotype suppressed in Hes1−/−Neurog3−/− embryos. Analysis of other Notch pathway mutants uncovered a total depletion of progenitors in Mib1 deficient dorsal anlage, which was replaced by an anterior Gcg+ extension. Together, our results demonstrate that aberrant morphogenesis is the cause of ectopic pancreas and that a part of the endocrine differentiation program is mechanistically involved in the dysgenesis. Our results suggest that the ratio of endocrine lineage to progenitor cells is important for morphogenesis and that a strong endocrinogenic phenotype without complete progenitor depletion as seen in Hes1 mutants provokes an extreme dysgenesis that causes ectopic pancreas.
Project description:RNA-seq of Human Embryonic Stem Cell derived pancreas progenitor differentiation, Day 13 of wildtype, HES1-/-, NEUROG3-/- and HES1-/-NEUROG3-/- genotypes
Project description:High levels of Hes1 expression are frequently found in BCR-ABL-positive chronic myelogenous leukemia in blast crisis (CML-BC). In mouse bone marrow transplantation (BMT) models, co-expression of BCR-ABL and Hes1 induces CML-BC–like disease; however the underlying mechanism remained elusive. Here, based on gene expression analysis, we show that MMP-9 is upregulated by Hes1 in common myeloid progenitors (CMPs). Analysis of promoter activity demonstrated that Hes1 upregulated MMP-9 by activating NF-kB. Analysis of 20 samples from CML-BC patients showed that MMP-9 was highly expressed in three, with two exhibiting high levels of Hes1 expression. Interestingly, MMP-9 deficiency impaired the cobblestone area-forming ability of CMPs expressing BCR-ABL and Hes1 that were in conjunction with a stromal cell layer. In addition, these CMPs secreted MMP-9, promoting the release of soluble Kit-ligand (sKitL) from stromal cells, thereby enhancing proliferation of the leukemic cells. In accordance, mice transplanted with CMPs expressing BCR-ABL and Hes1 exhibited high levels of sKitL as well as MMP-9 in the serum. Importantly, MMP-9 deficiency impaired the development of CML-BC–like disease induced by BCR-ABL and Hes1 in mouse BMT models. The present results suggest that Hes1 promotes the development of CML-BC, partly through MMP-9 upregulation in leukemic cells. Common myeloid progenitors (CMPs; Lineage negative, c-Kit positive, Sca-1 negative, Fc-gamma-receptor low, CD34 positive fraction) were sorted with a FACSAria cell sorter (Becton Dickinson). Retroviruses were generated by transfecting Plat-E packaging cells with retrovirus vector pMYs-Hes1-IRES-GFP or empty vector (pMYs-IRES-GFP) using FuGENE 6 (Roche Diagnostics). Infection of retrovirus harboring Hes1 (pMYs-Hes1-IRES-GFP) or empty vector (pMYs-IRES-GFP) into progenitors was performed using RetroNectin (Takara Bio). Hes1-transfected CMPs and Mock-transduced CMPs were isolated 36 hours after infection with a FACSAria cell sorter. One sample of Hes1-transfected CMPs and one sample of mock-transduced CMPs were analyzed with GeneChip Mouse Genome 430 2.0 Array.
Project description:High levels of Hes1 expression are frequently found in BCR-ABL-positive chronic myelogenous leukemia in blast crisis (CML-BC). In mouse bone marrow transplantation (BMT) models, co-expression of BCR-ABL and Hes1 induces CML-BC–like disease; however the underlying mechanism remained elusive. Here, based on gene expression analysis, we show that MMP-9 is upregulated by Hes1 in common myeloid progenitors (CMPs). Analysis of promoter activity demonstrated that Hes1 upregulated MMP-9 by activating NF-kB. Analysis of 20 samples from CML-BC patients showed that MMP-9 was highly expressed in three, with two exhibiting high levels of Hes1 expression. Interestingly, MMP-9 deficiency impaired the cobblestone area-forming ability of CMPs expressing BCR-ABL and Hes1 that were in conjunction with a stromal cell layer. In addition, these CMPs secreted MMP-9, promoting the release of soluble Kit-ligand (sKitL) from stromal cells, thereby enhancing proliferation of the leukemic cells. In accordance, mice transplanted with CMPs expressing BCR-ABL and Hes1 exhibited high levels of sKitL as well as MMP-9 in the serum. Importantly, MMP-9 deficiency impaired the development of CML-BC–like disease induced by BCR-ABL and Hes1 in mouse BMT models. The present results suggest that Hes1 promotes the development of CML-BC, partly through MMP-9 upregulation in leukemic cells.
Project description:Development of the pancreas from the endoderm is initiated at embryonic day 9 of mouse development and over the following days several different cell types develop from pancreas progenitor cells. A distinct phase of pancreas development, known as the secondary transition, is initiated at day 13 of development and one of the key features of this transition is a massive increase in the number of mature endocrine cells. To study gene expression in pancreas during the secondary transition we performed high-density oligonucleotide microarray experiments on dorsal pancreas tissue isolated from NMRI embryos on consecutive days from e12.5 to e16.5. Keywords: time course