Project description:Histamine defeciency result to hypertrophic gastropathy in the stomach. We use gene array to distover the major cause of stomach lesion in Hdc-/-. Tesult shows that chronic inflammation and dysregulation of macrophage functions are the major trigger for hypertrophic gastropathy in Hdc--/- stomach.
Project description:Histamine is a critical mediator of anaphylaxis, a neurotransmitter, and a regulator of gastric acid secretion. Histidine decarboxylase is a rate-limiting enzyme for histamine synthesis. However, in vivo regulation of Hdc, the gene that encodes histidine decarboxylase is poorly understood. We sought to investigate how enhancers regulate Hdc gene transcription and histamine synthesis in resting conditions and in a mouse model of anaphylaxis. H3K27 acetylation histone modification and chromatin accessibility were used to identify candidate enhancers; The enhancer activity of candidate enhancers was measured in a reporter gene assay; and the function enhancers were validated using CRISPR deletion. Deletion of the GC box, which binds to zinc finger transcription factors, in the proximal Hdc enhancer, reduced Hdc gene transcription and histamine synthesis in the mouse and human mast cell lines. Mast cells, basophils, brain cells, and stomach cells from GC box-deficient mice transcribed the Hdc gene much less than similar cells from wild-type mice and Hdc GC box-deficient mice failed to develop anaphylaxis. Our results demonstrate that the HDC GC box within the proximal enhancer in the mouse and human HDC gene is essential for Hdc gene transcription, histamine synthesis, and histamine-mediated anaphylaxis in vitro and in vivo.
Project description:Histamine is a critical mediator of anaphylaxis, a neurotransmitter, and a regulator of gastric acid secretion. Histidine decarboxylase is a rate-limiting enzyme for histamine synthesis. However, in vivo regulation of Hdc, the gene that encodes histidine decarboxylase is poorly understood. We sought to investigate how enhancers regulate Hdc gene transcription and histamine synthesis in resting conditions and in a mouse model of anaphylaxis. H3K27 acetylation histone modification and chromatin accessibility were used to identify candidate enhancers; The enhancer activity of candidate enhancers was measured in a reporter gene assay; and the function enhancers were validated using CRISPR deletion. Deletion of the GC box, which binds to zinc finger transcription factors, in the proximal Hdc enhancer, reduced Hdc gene transcription and histamine synthesis in the mouse and human mast cell lines. Mast cells, basophils, brain cells, and stomach cells from GC box-deficient mice transcribed the Hdc gene much less than similar cells from wild-type mice and Hdc GC box-deficient mice failed to develop anaphylaxis. Our results demonstrate that the HDC GC box within the proximal enhancer in the mouse and human HDC gene is essential for Hdc gene transcription, histamine synthesis, and histamine-mediated anaphylaxis in vitro and in vivo.
Project description:Bone marrow Hdc-GFP+/hi and Hdc-GFP-/loCD11b+Gr1+ cells were isolated from bones from histidine decarboxylase (Hdc) green fluorescent protein (Hdc-GFP) mice Hdc-GFP+/hiCD11b+Gr1+ cells and Hdc-GFP-/loCD11b+Gr1+ cells were sorted by combinations of GFP and myeloid cell surface markers CD11b and Gr1 and their differential mRNA expression compared with Affymetrix microarrays.
Project description:Bone marrow Hdc-GFP+/hiCD11b+Gr1lo vs Hdc-GFP+/hiCD11b+Gr1hi myeloid cells were isolated from bones from histidine decarboxylase (Hdc) green fluorescent protein (Hdc-GFP) mice. Hdc-GFP+/hiCD11b+Gr1hi cells and Hdc-GFP+/hiCD11b+Gr1/lo cells were sorted by combinations of GFP and myeloid cell surface markers CD11b and Gr1 and their differential mRNA expression compared with Affymetrix microarrays.
Project description:We take one-year-old plants for high-temperature treatments and controls. We used the Affymetrix Poplar GeneChip to decrypt the gene functions and mechanisms in Populus simonii leaves.
Project description:Bone marrow Hdc-GFPhi and Hdc-GFPlo HSPC (SLAM-LSK, Lin-c-kit+Sca-1+CD150+CD48-) HSCs were isolated from mouse femur and tibia from histidine decarboxylase (Hdc) green fluorescent protein (Hdc-GFP) mice. Hdc-GFPhi HSC and Hdc-GFPlo HSC cells were sorted by combinations of GFP and the cell surface markers of HSC. total RNA was isolated from sorted 2,500 HSPCs using ARCTURUS PicoPure RNA isolation kit (Life Technologies). cDNA was amplified and libraries were constructed by using SMARTer Ultra Low Input RNA kit (Clontech Laboratories) and Nextera XT DNA Library Preparation kit (Illumina) according to manufacturer’s instructions respectively. Sequencing was performed on the Illumina HiSeq2000 platform.