Project description:Natural killer (NK) cells can be grouped into distinct subsets that are localized to different organs and exhibit different capacity to secrete cytokines and mediate cytotoxicity. Despite these hallmarks that reflect tissue-specific specialization in NK cells, little is known about the factors that control the development of these distinct subsets. The basic leucine zipper transcription factor nuclear factor interleukin 3 (Nfil3; E4bp4) is essential for bone marrow-derived NK cell development but it is not clear whether Nfil3 is equally important for all NK cell subsets nor how it induces NK lineage commitment. Here we show that Nfil3 is required for the formation of Eomesodermin (Eomes)-expressing NK cells, including conventional medullary and thymic NK cells, whereas TRAIL+ Eomes- NK cells develop independent of Nfil3. Loss of Nfil3 during the development of bone marrow-derived NK cells resulted in reduced expression of Eomes and, conversely, restoration of Eomes expression in Nfil3-/- progenitors rescued NK cell development and maturation. Collectively, these findings demonstrate that Nfil3 drives the formation of mature NK cell by inducing Eomes expression and reveal the differential requirements of NK cell subsets for Nfil3. RNA-sequencing of natural killer (NK) cell subsets
Project description:Natural killer (NK) cells can be grouped into distinct subsets that are localized to different organs and exhibit different capacity to secrete cytokines and mediate cytotoxicity. Despite these hallmarks that reflect tissue-specific specialization in NK cells, little is known about the factors that control the development of these distinct subsets. The basic leucine zipper transcription factor nuclear factor interleukin 3 (Nfil3; E4bp4) is essential for bone marrow-derived NK cell development but it is not clear whether Nfil3 is equally important for all NK cell subsets nor how it induces NK lineage commitment. Here we show that Nfil3 is required for the formation of Eomesodermin (Eomes)-expressing NK cells, including conventional medullary and thymic NK cells, whereas TRAIL+ Eomes- NK cells develop independent of Nfil3. Loss of Nfil3 during the development of bone marrow-derived NK cells resulted in reduced expression of Eomes and, conversely, restoration of Eomes expression in Nfil3-/- progenitors rescued NK cell development and maturation. Collectively, these findings demonstrate that Nfil3 drives the formation of mature NK cell by inducing Eomes expression and reveal the differential requirements of NK cell subsets for Nfil3.
Project description:Nfil3 has multiple functions during conventional NK cell and thymic NK cell development. Nfil3 controls NK cell development from the earliest committed NK cell progenitor stage. Nfil3-/- prepro NK cells retained T-cell potential due to the failure to repress T cell specific genes. At later stages of NK cell development, Nfil3 regulates the formation of mature NK cells by promoting directly or indirectly the expression of transcription factor Eomes. We also demonstrate that Nfil3 is important for thymic NK cell development whereas Trail+ immature NK cells generated in the bone marrow of neonates and in the adult liver develop independent of Nfil3 function. We used microarrays to analyse the changes in gene expression due to the presence or absence of Nfil3, both in prepro NK cells and ALP cells (all lymphoid progenitors) Samples were obtained on two experimentation dates. Replicate 1 was processed in April 2012, replicate 2 was processed in May 2012.
Project description:Nfil3 has multiple functions during conventional NK cell and thymic NK cell development. Nfil3 controls NK cell development from the earliest committed NK cell progenitor stage. Nfil3-/- prepro NK cells retained T-cell potential due to the failure to repress T cell specific genes. At later stages of NK cell development, Nfil3 regulates the formation of mature NK cells by promoting directly or indirectly the expression of transcription factor Eomes. We also demonstrate that Nfil3 is important for thymic NK cell development whereas Trail+ immature NK cells generated in the bone marrow of neonates and in the adult liver develop independent of Nfil3 function. We used microarrays to analyse the changes in gene expression due to the presence or absence of Nfil3, both in prepro NK cells and ALP cells (all lymphoid progenitors)
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: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.
Project description:BackgroundLong 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.ResultsUsing 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.ConclusionsAll 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.