Project description:Because activation of the immune response is dependent on extensive changes in gene expression, it is likely that a major component of inter-individual variation in the immune response is ultimately mediated at the level of gene regulation. Here, we examine the influence of genetic variation on inducible gene expression in the murine immune response. We report strain-specific genome-wide differences in mRNA expression between NOD and B10 inbred mice in CD4 splenocytes in basal, stimulated (4hr, PMA/I) states.
Project description:Nonobese diabetic (NOD) mice congenic for B10 derived genes in the Idd9 region of chromosome 4 are highly protected from the development of diabetes. In order to identify possible candidate genes within the Idd9 susceptibility region and possible downstream mediators of protection, we compared gene expression between NOD and Idd9 CD4+ T-cells. CD4+ T-cells with an activated phenotype (CD44-high/CD62L-low) were sorted from the pancreatic lymph nodes of female 8-week old mice. Mice were bred at Taconic farms and were line 905 (NOD.B10-Idd9 congenic) and line 6359 (NOD-like control strain with a B10 congenic region on chromosome 1 which does not modify diabetes incidence). Three replicate samples were prepared, each from four pooled pancreatic lymph nodes. CD4+CD44-highCD62L-low T-cells were sorted from each sample.
Project description:Cellular binary fate decisions require the progeny to silence genes associated with the alternative fate. The major subsets of alpha:beta T cells have been extensively studied as a model system for fate decisions. While the transcription factor RUNX3 is required for the initiation of Cd4 silencing in CD8 T cell progenitors, it is not required to maintain the silencing of Cd4 and other helper T lineage genes. The other runt domain containing protein, RUNX1, silences Cd4 in an earlier T cell progenitor, but this silencing is reversed whereas the gene silencing after RUNX3 expression is not reverse. Therefore, we hypothesized that RUNX3 and not RUNX1 recruits other factors that maintains the silencing of helper T lineage genes in CD8 T cells. To this end, we performed a proteomics screen of RUNX1 and RUNX3 to determine candidate silencing factors.
Project description:Nonobese diabetic (NOD) mice congenic for B10 derived genes in the Idd9 region of chromosome 4 are highly protected from the development of diabetes. In order to identify possible candidate genes within the Idd9 susceptibility region and possible downstream mediators of protection, we compared gene expression between NOD and Idd9 CD4+ T-cells. CD4+ T-cells with an activated phenotype (CD44-high/CD62L-low) were sorted from the pancreatic lymph nodes of female 8-week old mice.
Project description:We collected whole genome testis expression data from hybrid zone mice. We integrated GWAS mapping of testis expression traits and low testis weight to gain insight into the genetic basis of hybrid male sterility.
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.