Project description:Background and Aims: p53 can limit the self-renewal of stem cells from various tissues. Experimental evidence suggests that deletion of p53 can cooperate with other oncogenic events to induce aberrant self-renewal and transformation of progenitor cells. It is not known whether p53 deletion alone can lead to liver tumor formation. Methods: We used AlfpCre mice for liver-specific deletion of Trp53 in a conditional knockout mouse model to analyze liver carcinogenesis. Results: Here, we show that liver-specific deletion of p53 in mice consistently induces formation of liver carcinoma depicting bilineal differentiation. Freshly isolated p53-/- liver progenitor cells and hepatocytes exhibit chromosomal imbalances and an enhanced clonogenic capacity compared to p53-positive cells or p21-deficient cells. Primary cultures of hepatocytes and liver progenitor cells from p53-/- mice formed tumors with bilineal differentiation when transplanted into immuno-compromised mice. Together, these results indicate that loss of p53 alone is sufficient to induce primary liver cancer with bilineal differentiation originating from chromosomal instable cultured liver progenitor cells or hepatocytes. Conclusions: The study shows that p53-dependent checkpoints inhibit transformation of liver progenitor cells and hepatocytes involving p21-independent mechanisms. Liver tumors derived from Trp53 KO mice, liver tumors from DEN-treated wildtype mice, Trp53 KO liver and wildtype liver were isolated and RNA was extracted. Agilent-026655 Mouse 4x44K v2 arrays were used.
Project description:Background and Aims: p53 can limit the self-renewal of stem cells from various tissues. Experimental evidence suggests that deletion of p53 can cooperate with other oncogenic events to induce aberrant self-renewal and transformation of progenitor cells. It is not known whether p53 deletion alone can lead to liver tumor formation. Methods: We used AlfpCre mice for liver-specific deletion of Trp53 in a conditional knockout mouse model to analyze liver carcinogenesis. Results: Here, we show that liver-specific deletion of p53 in mice consistently induces formation of liver carcinoma depicting bilineal differentiation. Freshly isolated p53-/- liver progenitor cells and hepatocytes exhibit chromosomal imbalances and an enhanced clonogenic capacity compared to p53-positive cells or p21-deficient cells. Primary cultures of hepatocytes and liver progenitor cells from p53-/- mice formed tumors with bilineal differentiation when transplanted into immuno-compromised mice. Together, these results indicate that loss of p53 alone is sufficient to induce primary liver cancer with bilineal differentiation originating from chromosomal instable cultured liver progenitor cells or hepatocytes. Conclusions: The study shows that p53-dependent checkpoints inhibit transformation of liver progenitor cells and hepatocytes involving p21-independent mechanisms.
Project description:Background and Aims: Analysis of aging-induced impairments in satellite cells (SCs) – the stem cells of skeletal muscle that are required for its regeneration. Hox genes are known to control stem cell function and development of various tissues. Methods: We used AlfpCre mice for liver specific deletion of Trp53 in a conditional knockout mouse model to analyze liver carcinogenesis. Results: Here, we show that liver-specific deletion of p53 in mice consistently induces formation of liver carcinoma depicting bilineal differentiation. Freshly isolated p53-/- liver progenitor cells and hepatocytes exhibit chromosomal imbalances and an enhanced clonogenic capacity compared to p53-positive cells or p21-deficient cells. Primary cultures of hepatocytes and liver progenitor cells from p53-/- mice formed tumors with bilineal differentiation when transplanted into immuno-compromised mice. Together, these results indicate that loss of p53 alone is sufficient to induce primary liver cancer with bilineal differentiation originating from chromosomal instable cultured liver progenitor cells or hepatocytes. Conclusions: The study shows that p53-dependent checkpoints inhibit transformation of liver progenitor cells and hepatocytes involving p21-independent mechanisms. In this study the function of the Hoxa9 was analyzed in murine satellite cells.
Project description:SILAC based protein correlation profiling using size exclusion of protein complexes derived from Mus musculus tissues (Heart, Liver, Lung, Kidney, Skeletal Muscle, Thymus)
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:SILAC based protein correlation profiling using size exclusion of protein complexes derived from seven Mus musculus tissues (Heart, Brain, Liver, Lung, Kidney, Skeletal Muscle, Thymus)
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:Background and aims: P53 limits the self-renewal of stem cells from various tissue. A Loss of p53 in combination with other oncogenic events results in aberrant self-renewal and transformation of progenitor cells. Here, we investigated whether a loss of p53 as a single genetic lesion is sufficient to induce liver tumor formation. Methods: AlfpCre mice were crossed with Trp53 conditional knockout mice to achieve a liver-specific loss of Trp53. Results: The liver-specific loss of Trp53 results in liver tumor formation. A high percentage of the tumors showed a mixed differentiation of hepatocellular carcinoma and intrahepatic cholangiocarcinoma. Conclusion: The liver-specific deletion of Trp53 is sufficient to induce liver tumor formation.
Project description:Background and aims: P53 limits the self-renewal of stem cells from various tissue. A Loss of p53 in combination with other oncogenic events results in aberrant self-renewal and transformation of progenitor cells. Here, we investigated whether a loss of p53 as a single genetic lesion is sufficient to induce liver tumor formation. Methods: AlfpCre mice were crossed with Trp53 conditional knockout mice to achieve a liver-specific loss of Trp53. Results: The liver-specific loss of Trp53 results in liver tumor formation. A high percentage of the tumors showed a mixed differentiation of hepatocellular carcinoma and intrahepatic cholangiocarcinoma. Conclusion: The liver-specific deletion of Trp53 is sufficient to induce liver tumor formation.
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.