Project description:Cut & Run analysis was performed in an neuroblastoma cell line to analyze DNA bindings of ASCL1-tag-HA in GI-MEN ASCL1-tag-HA cells and GI-MEN ASCL1-tag-HA+4TFs cells; analyze DNA bindings of MYCN, PHOX2B and H3K27ac in, GI-MEN 4TFs cells, and GI-MEN ASCL1-tag-HA+4TFs cells.
Project description:GIGANTEA (GI) is an important modulator of plant circadian system. Recent studies have reported that protein GI is localized in both nucleus and cytosol, and nuclear and cytosolic GI exert differential effect on plant circadian clock. We first generated GI-null mutants and transgenic Arabidopsis plants that expressed GI fused to green fluorescent protein gene (GIpro::GI-GFP) and GI-GFP with a nuclear localization signal (GIpro::GI-GFP-NLS) or with a nuclear export signal (GIpro::GI-GFP-NES) under the control of native promoter in GI-null mutants. To investigate differential roles of nuclear and cytosolic GI in regulating plant circadian clock, we performed genome-wide gene expression profiling for wild-type plants and the GI-transgenic plants at morning and evening, and analyzed complementation patterns of gi-2 lesion by nuclear and cytosolic GI. As a result, we identified four complementation patterns representing genes affected by only nuclear GI (GIN) or cytosolic GI (GIC), those by either GIN or GIC, and those by the action of both GIN and GIC. Furthermore, we compared the transgenic plants expressing GIpro::GI-GFP with WT and the other GI-transgenic plants to confirm whether abnormally expressed genes by the gi-2 mutation can be complemented by restoring protein GI. Wild-type plants (Col), GI-null mutants (gi-2), and the other transgenic gi-2 plants expressing GIpro::GI-GFP (called GI plants), GIpro::GI-GFP-NLS (called GI-NLS plants), and GIpro::GI-GFP-NES (called GI-NES plants) were grown for seven days under conditions of 16 h light and 8 h dark (LD) and harvested at 1h (ZT1) and 16 hr (ZT16) after the light is turned on, representing morning and evening, respectively. mRNA levels were measured from three biological replicates of Col, gi-2, GI-NLS, GI-NES, and GI.
Project description:GIGANTEA (GI) is an important modulator of plant circadian system. Recent studies have reported that protein GI is localized in both nucleus and cytosol, and nuclear and cytosolic GI exert differential effect on plant circadian clock. We first generated GI-null mutants and transgenic Arabidopsis plants that expressed GI fused to green fluorescent protein gene (GIpro::GI-GFP) and GI-GFP with a nuclear localization signal (GIpro::GI-GFP-NLS) or with a nuclear export signal (GIpro::GI-GFP-NES) under the control of native promoter in GI-null mutants. To investigate differential roles of nuclear and cytosolic GI in regulating plant circadian clock, we performed genome-wide gene expression profiling for wild-type plants and the GI-transgenic plants at morning and evening, and analyzed complementation patterns of gi-2 lesion by nuclear and cytosolic GI. As a result, we identified four complementation patterns representing genes affected by only nuclear GI (GIN) or cytosolic GI (GIC), those by either GIN or GIC, and those by the action of both GIN and GIC. Furthermore, we compared the transgenic plants expressing GIpro::GI-GFP with WT and the other GI-transgenic plants to confirm whether abnormally expressed genes by the gi-2 mutation can be complemented by restoring protein GI.
Project description:H3K27ac HiChIP analysis was performed in GI-MEN DOX-ASCL1 cells to analyze active chromatin-chromatin interactions in GI-MEN DOX-ASCL1 cells.
Project description:Matrigel, a mouse tumor extracellular matrix (ECM) protein mixture, is an indispensable component of most organoid tissue culture. However, it has limited the utility of organoids for drug development and regenerative medicine due to its tumor-derived origin, batch-to batch variation, high cost, and safety issues. Here, we demonstrate that gastrointestinal (GI) tissue-derived ECM hydrogels are a suitable substitute for Matrigel in GI organoid culture. We found that the development and function of GI organoids grown in GI ECM hydrogels are comparable or often superior to those in Matrigel. In addition, GI ECM hydrogels enabled long-term subculture and transplantation of GI organoids by providing GI tissue-mimetic microenvironments. Tissue-specific and age-related ECM profiles of GI ECM hydrogels that affect organoid development were also elucidated through proteomic analysis. Together, our results suggest that ECM hydrogels derived from decellularized GI tissues are an effective alternative to the current gold standard, Matrigel, and produce organoids suitable for GI disease modeling, drug development, and tissue regeneration.
Project description:Matrigel, a mouse tumor extracellular matrix (ECM) protein mixture, is an indispensable component of most organoid tissue culture. However, it has limited the utility of organoids for drug development and regenerative medicine due to its tumor-derived origin, batch-to22 batch variation, high cost, and safety issues. Here, we demonstrate that gastrointestinal (GI) tissue-derived ECM hydrogels are a suitable substitute for Matrigel in GI organoid culture. We found that the development and function of GI organoids grown in GI ECM hydrogels are comparable or often superior to those in Matrigel. In addition, GI ECM hydrogels enabled long-term subculture and transplantation of GI organoids by providing GI tissue-mimetic microenvironments. Tissue-specific and age-related ECM profiles of GI ECM hydrogels that affect organoid development were also elucidated through proteomic analysis. Together, our results suggest that ECM hydrogels derived from decellularized GI tissues are an effective alternative to the current gold standard, Matrigel, and produce organoids suitable for GI disease modeling, drug development, and tissue regeneration.
Project description:DNA methylation is a key epigenetic modification that can regulate gene expression. Genomic DNA hypomethylation is commonly found in many gastrointestinal (GI) diseases. Dysregulated gene expression in GI smooth muscle cells (GI-SMC) can lead to motility disorders. However, the consequences of genomic DNA hypomethylation within GI-SMC are still elusive. Utilizing a Cre-lox murine model, we have generated SMC-restricted DNA methyltransferase 1 (Dnmt1) knockout (KO) mice and analyzed the effects of Dnmt1 deficiency. Dnmt1-KO pups are born smaller than their wild type littermates, have shortened GI tracts, lose peristaltic movement due to loss of the tunica muscularis in their intestine, causing massive intestinal dilation, and death around post-natal day 21. Within smooth muscle tissue, significant CpG hypomethylation occurs across the genome at promoters, introns and exons. Additionally, there is a marked loss of differentiated SMC markers (Srf, Myh11, miR-133, miR-143/145), an increase in pro-apoptotic markers (Nr4a1, Gadd45g), loss of cellular connectivity, and an accumulation of coated vesicles within SMC. Interestingly, we observed consistent abnormal expression patterns of enzymes involved in DNA methylation between both ¬Dnmt1-KO mice and diseased human GI tissue. These data demonstrate that DNA hypomethylation in embryonic SMC, via congenital Dnmt1 deficiency, contributes to massive dysregulation of gene expression and is lethal to GI-SMC. These results suggest that Dnmt1 has a necessary role in the embryonic, primary development process of SMC with consistent patterns being found in human GI diseased tissue.
Project description:ChIP-seq analysis was performed in an neuroblastoma cell line to analyze DNA bindings of H3K27ac in GI-MEN DOX-ASCL1 cells and ASCL1-HA in GI-MEN DOX-ASCL1-tag-HA cells.