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:In mammalian systems, extracellular small RNAs can operate in a paracrine manner to communicate information between cells, relying on transport within vesicles. “Foreign” small RNAs derived from bacteria, plants and parasites have also been detected in mammalian body fluids, sparking interest in whether these could mediate inter-species communication. However, there is no mechanistic framework for RNA-mediated interspecies communication and the active movement of RNA via vesicles has not been shown outside of mammals. Here we demonstrate that specific microRNAs and Y RNAs are packaged into vesicles secreted by a gastrointestinal nematode, Heligmosomoides polygyrus, which naturally infects mice. Total RNA was extracted from the serum of mice infected with Litomosoides sigmodontis at 60 days post infection
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:A LINE-1 element, LIC105, was found in the Mus musculus domesticus inbred strain, C57BL/6J. Upon sequencing, this element was found to belong to a M. spretus LINE-1 subfamily originating within the last 0.2 million years. This is the second spretus-specific LINE-1 subfamily found to be represented in C57BL/6J. Although it is unclear how these M. spretus LINE-1s transferred from M. spretus to M. m. domesticus, it is now clear that at least two different spretus LINE-1 sequences have recently transferred. The limited divergence between the C57BL/6J spretus-like LINE-1s and their closest spretus ancestors suggests that the transfer did not involve an exceptionally long lineage of sequential transpositions.
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:To investigate changes in serum extracellular vesicle miRNAs during adipose tissue regeneration, we created tamoxifen-inducible adipocyte-specific insulin receptor knockout (iFIRKO) mice. We then performed comprehensive miRNA analysis on the serum extracellular vesicles of iFIRKO and control mice.
Project description:Small RNAs are emerging as important molecules for cross-species communication. Thanks to available and affordable sequencing technologies it is now possible to sequence small RNAs (sRNA-Seq) present in samples of interacting organisms. A first step when analyzing sRNA-Seq of two interacting species is to determine which sequences are being produced by which organism. Due to their small size (18-30), small RNAs could easily map to both host and parasite genomes. Here we produced data for Mus musculus intestinal epithelial cells treated with Extracellular Vesicles (EV) produced by the parasitic nematode Heligmosomoides bakeri.