Project description:This SuperSeries is composed of the following subset Series:; GSE11533: Autoregulation of Th1-mediated inflammation by twist1 1st part; GSE11534: Autoregulation of Th1-mediated inflammation by twist1 2nd part Experiment Overall Design: Refer to individual Series
Project description:The basic helix-loop-helix transcriptional repressor twist1, as an antagonist of nuclear factor κB (NF-κB)-dependent cytokine expression, is involved in the regulation of inflammation-induced immunopathology. We could show that twist1 is expressed by activated T helper (Th) 1 effector memory cells. Induction of twist1 in Th cells is dependent on NF-κB, nuclear factor of activated T cells (NFAT), and interleukin (IL)-12 signaling via signal transducer and activator of transcription (STAT) 4. Expression of twist1 is transient following T-cell receptor engagement, and increases upon repeated stimulation of Th1 cells. Imprinting for enhanced twist1 expression is characteristic of repeatedly restimulated effector memory Th cells and thus of the pathogenic memory Th cells of chronic inflammation. Th lymphocytes from the inflamed joint or gut tissue of patients with rheumatic diseases, Crohn’s disease or ulcerative colitis express high levels of twist1. Expression of twist1 in Th1 lymphocytes limits the expression of the cytokines interferon-γ, IL-2 and tumor necrosis factor-α, and ameliorates Th1-mediated immunopathology in delayed-type hypersensitivity and antigen-induced arthritis. In order to identify the effect of twist1 expression on the function of Th cells, twist1 was ectopically expressed and the transcriptome was compared to empty-virus infected control cells. In addition, this experiment allows for the identification of genes regulated by the transcription factor twist1.
Project description:The basic helix-loop-helix transcriptional repressor twist1, as an antagonist of nuclear factor κB (NF-κB)-dependent cytokine expression, is involved in the regulation of inflammation-induced immunopathology. We could show that twist1 is expressed by activated T helper (Th) 1 effector memory cells. Induction of twist1 in Th cells is dependent on NF-κB, nuclear factor of activated T cells (NFAT), and interleukin (IL)-12 signaling via signal transducer and activator of transcription (STAT) 4. Expression of twist1 is transient following T-cell receptor engagement, and increases upon repeated stimulation of Th1 cells. Imprinting for enhanced twist1 expression is characteristic of repeatedly restimulated effector memory Th cells and thus of the pathogenic memory Th cells of chronic inflammation. Th lymphocytes from the inflamed joint or gut tissue of patients with rheumatic diseases, Crohnâ??s disease or ulcerative colitis express high levels of twist1. Expression of twist1 in Th1 lymphocytes limits the expression of the cytokines interferon-γ, IL-2 and tumor necrosis factor-α, and ameliorates Th1-mediated immunopathology in delayed-type hypersensitivity and antigen-induced arthritis. In order to identify the effect of twist1 expression on the function of Th cells, twist1 was ectopically expressed and the transcriptome was compared to empty-virus infected control cells. In addition, this experiment allows for the identification of genes regulated by the transcription factor twist1. Experiment Overall Design: Genes differentially expressed upon ectopic twist1 overexpression. Splenic DO11.10 cells were activated in vitro with the cognate peptide ova327-339 in the presence of 1ng/ml IL-12 and 1ng/ml IL-2. On day 2 cells were infected with control virus, or twist1-encoding virus. On day 5 cells were sorted according to expression of the viral marker gene gfp. Cells were restimulated for four hours with PMA/ionomycin. The transcriptional profiles of duplicates of cultures were compared using Affymetrix Murine Genome (MG) 430A 2.0 GeneChip arrays.
Project description:Introgressed variants from other species can be an important source of genetic variation because they may arise rapidly, can include multiple mutations on a single haplotype, and have often been pretested by selection in the species of origin. Although introgressed alleles are generally deleterious, several studies have reported introgression as the source of adaptive alleles-including the rodenticide-resistant variant of Vkorc1 that introgressed from Mus spretus into European populations of Mus musculus domesticus. Here, we conducted bidirectional genome scans to characterize introgressed regions into one wild population of M. spretus from Spain and three wild populations of M. m. domesticus from France, Germany, and Iran. Despite the fact that these species show considerable intrinsic postzygotic reproductive isolation, introgression was observed in all individuals, including in the M. musculus reference genome (GRCm38). Mus spretus individuals had a greater proportion of introgression compared with M. m. domesticus, and within M. m. domesticus, the proportion of introgression decreased with geographic distance from the area of sympatry. Introgression was observed on all autosomes for both species, but not on the X-chromosome in M. m. domesticus, consistent with known X-linked hybrid sterility and inviability genes that have been mapped to the M. spretus X-chromosome. Tract lengths were generally short with a few outliers of up to 2.7 Mb. Interestingly, the longest introgressed tracts were in olfactory receptor regions, and introgressed tracts were significantly enriched for olfactory receptor genes in both species, suggesting that introgression may be a source of functional novelty even between species with high barriers to gene flow.
Project description:Translational research is commonly performed in the C57B6/J mouse strain, chosen for its genetic homogeneity and phenotypic uniformity. Here, we evaluate the suitability of the white-footed deer mouse (Peromyscus leucopus) as a model organism for aging research, offering a comparative analysis against C57B6/J and diversity outbred (DO) Mus musculus strains. Our study includes comparisons of body composition, skeletal muscle function, and cardiovascular parameters, shedding light on potential applications and limitations of P. leucopus in aging studies. Notably, P. leucopus exhibits distinct body composition characteristics, emphasizing reduced muscle force exertion and a unique metabolism, particularly in fat mass. Cardiovascular assessments showed changes in arterial stiffness, challenging conventional assumptions and highlighting the need for a nuanced interpretation of aging-related phenotypes. Our study also highlights inherent challenges associated with maintaining and phenotyping P. leucopus cohorts. Behavioral considerations, including anxiety-induced responses during handling and phenotyping assessment, pose obstacles in acquiring meaningful data. Moreover, the unique anatomy of P. leucopus necessitates careful adaptation of protocols designed for Mus musculus. While showcasing potential benefits, further extensive analyses across broader age ranges and larger cohorts are necessary to establish the reliability of P. leucopus as a robust and translatable model for aging studies.
Project description:This is an investigation of whole genome gene expression level in tissues of mice stimulated by LPS, FK565 or LPS + FK565 in vivo and ex vivo. We show that parenteral administration of a pure synthetic Nod1 ligand, FK565, induces site-specific vascular inflammation in mice, which is prominent in aortic root including aortic valves, slight in aorta and absent in other arteries. The degree of respective vascular inflammation is associated with persistent high expression of proinflammatory chemokine/cytokine genes in each tissue in vivo by microarray analysis, and not with Nod1 expression levels. The ex vivo production of proinflammatory chemokine/cytokine by Nod1 ligand is higher in aortic root than in other arteries from normal murine vascular tissues, and also higher in human coronary artery endothelial cells (HCAEC) than in human pulmonary artery endothelial cells (HPAEC), suggesting that site-specific vascular inflammation is at least in part ascribed to an intrinsic nature of the vascular tissue/cell itself.
Project description:BACKGROUND: Long terminal repeat (LTR) retrotransposons make up a large fraction of the typical mammalian genome. They comprise about 8% of the human genome and approximately 10% of the mouse genome. On account of their abundance, LTR retrotransposons are believed to hold major significance for genome structure and function. Recent advances in genome sequencing of a variety of model organisms has provided an unprecedented opportunity to evaluate better the diversity of LTR retrotransposons resident in eukaryotic genomes. RESULTS: Using a new data-mining program, LTR_STRUC, in conjunction with conventional techniques, we have mined the GenBank mouse (Mus musculus) database and the more complete Ensembl mouse dataset for LTR retrotransposons. We report here that the M. musculus genome contains at least 21 separate families of LTR retrotransposons; 13 of these families are described here for the first time. CONCLUSIONS: All families of mouse LTR retrotransposons are members of the gypsy-like superfamily of retroviral-like elements. Several different families of unrelated non-autonomous elements were identified, suggesting that the evolution of non-autonomy may be a common event. High sequence similarity between several LTR retrotransposons identified in this study and those found in distantly-related species suggests that horizontal transfer has been a significant factor in the evolution of mouse LTR retrotransposons.
Project description:BackgroundCopy number variation is an important dimension of genetic diversity and has implications in development and disease. As an important model organism, the mouse is a prime candidate for copy number variant (CNV) characterization, but this has yet to be completed for a large sample size. Here we report CNV analysis of publicly available, high-density microarray data files for 351 mouse tail samples, including 290 mice that had not been characterized for CNVs previously.ResultsWe found 9634 putative autosomal CNVs across the samples affecting 6.87% of the mouse reference genome. We find significant differences in the degree of CNV uniqueness (single sample occurrence) and the nature of CNV-gene overlap between wild-caught mice and classical laboratory strains. CNV-gene overlap was associated with lipid metabolism, pheromone response and olfaction compared to immunity, carbohydrate metabolism and amino-acid metabolism for wild-caught mice and classical laboratory strains, respectively. Using two subspecies of wild-caught Mus musculus, we identified putative CNVs unique to those subspecies and show this diversity is better captured by wild-derived laboratory strains than by the classical laboratory strains. A total of 9 genic copy number variable regions (CNVRs) were selected for experimental confirmation by droplet digital PCR (ddPCR).ConclusionThe analysis we present is a comprehensive, genome-wide analysis of CNVs in Mus musculus, which increases the number of known variants in the species and will accelerate the identification of novel variants in future studies.