Project description:In rodent liver, a single injection of N-nitrosodiethylamine (DEN) followed by chronic treatment with the antiepileptic drug phenobarbital (PB) promotes the outgrowth of hepatocellular tumors with activating mutations in Ctnnb1, encoding the transcription factor β-catenin. We now studied long-term effects of PB treatment in livers of transgenic mice with hepatocyte-specific knockout (KO) of Apc, a negative regulator of β-catenin signaling. The number of Apc KO hepatocytes present in the liver decreased with age, indicative of a selective disadvantage of Apc KO cells in the absence of PB. Following liver tumor promotion by PB in Apc KO mice for 9 months, tumor burden was quantified and histological appearance, gene expression profiles, and activity of oncogenic signaling pathways of the tumors were analyzed. In Apc KO mice fed with PB, we observed an increased hepatic tumor volume fraction and tumor multiplicity, as compared to non-promoted animals. Tumors in the PB-treated Apc KO group were mostly eosinophilic hepatocellular adenoma with activated β-catenin, due to the deletion of Apc. These tumors exhibited striking phenotypic similarities to DEN-induced Ctnnb1-mutated tumors, regarding histological appearance and expression of marker proteins and mRNAs. A particular sub-population of tumors, Apc KO-driven basophilic hepatocellular carcinomas, exclusively appeared in the non-PB-treated group but was absent from PB-promoted livers. In conclusion, phenobarbital promotes the outgrowth of Apc-deficient, β-catenin-activated hepatocellular adenoma while simultaneously inhibiting the formation of a certain population of Apc-driven hepatocellular carcinoma.
Project description:The aim of this study was to assess whether chronic treatment with RPV can modulate the progression of chronic liver disease, especially of non-alcoholic fatty liver disease (NAFLD), through a nutritional model in wild-type mice Mice were daily treated with RPV (p.o.) and fed with normal or high fat diet during 3 months to induce fatty liver disease
Project description:We identified the gene Far2, encoding the fatty acyl-coA reductase 2, to be associated with mesangial matrix expansion (MME) in the mouse (PMID: 24009241). In order to verify this association we obtained the C57BL/6N-Far2tm2a(KOMP)Wtsi/2J (JR#018805) strain from The Jackson Laboratory's KOMP2 program and compared this strain to it's control strain (C57BL/6N) for several renal characteristics. At 6 months of age the knockout mice have a significantly better kidney function (measured as glomerular filtration rate) but the MME is at a comparable level. However, as MME increases in the control strain at 12 months of age, MME does not increase in the knockout until 18 months of age. In order to explore changes at the gene expression level, we compared RNA sequence reads from 6-month old kidneys. Our analysis showed a decrease of RNA expression for several tubular damage markers (NGAL, KIM-1) and an increase in several genes in the fatty acid metabolism pathway.
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: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.