Project description:Findings suggest that PPARalpha plays a decisive role in the development of hypertrophy, affecting the functional outcome of the heart. Unfortunately, information on the nature of PPARalpha-dependent processes in cardiac hypertrophy is fragmentary and incomplete. The primary aim of this study was to identify the processes and signaling pathways regulated by PPARalpha in hearts challenged by a chronic pressure overload by means of whole genome transcriptomic analysis. Second, we wanted to gain insight how PPARalpha modulates the identified processes, e.g. by trans-activation or by trans-repression. Keywords: 28 days of TAC
Project description:Findings suggest that PPARalpha plays a decisive role in the development of hypertrophy, affecting the functional outcome of the heart. Unfortunately, information on the nature of PPARalpha-dependent processes in cardiac hypertrophy is fragmentary and incomplete. The primary aim of this study was to identify the processes and signaling pathways regulated by PPARalpha in hearts challenged by a chronic pressure overload by means of whole genome transcriptomic analysis. Second, we wanted to gain insight how PPARalpha modulates the identified processes, e.g. by trans-activation or by trans-repression. Experiment Overall Design: Wild-type and PPARalpha-/- mice were sham-operated or subjected to TAC for 28 days. Left ventricular gene expression profile was determined using Affymetrix 430 2.0 arrays containing over 45,000 probe sets (covering over 34,000 mouse genes) to detect PPARalpha-related differences in cardiac gene expression under basal conditions and after imposition of a sustained hemodynamic stress.
Project description:Cardiac-specific PPARalpha transgenic (Tg-PPARalpha) mice show mild cardiac hypertrophy and systolic dysfunction. The failing heart phenotypes observed in Tg-PPARalpha are exacerbated by crossing with cardiac-specific Sirt1 transgenic (Tg-Sirt1) mice, whereas Tg-Sirt1 mice themselves do not show any cardiac hypertrophy or systolic dysfunction. To investigate the mechanism leading to the failing heart phenotypes in TgPPARalpha/Tg-Sirt1 bigenic mice, microarray analyses were performed. The microarray analyses revealed that many ERR target genes were downregulated in Tg-PPARalpha and in Tg-Sirt1, and they were further downregulated in the Tg-PPARalpha/Tg-Sirt1 bigenic mice.
Project description:Cardiac-specific PPARalpha transgenic (Tg-PPARalpha) mice show mild cardiac hypertrophy and systolic dysfunction. The failing heart phenotypes observed in Tg-PPARalpha are exacerbated by crossing with cardiac-specific Sirt1 transgenic (Tg-Sirt1) mice, whereas Tg-Sirt1 mice themselves do not show any cardiac hypertrophy or systolic dysfunction. To investigate the mechanism leading to the failing heart phenotypes in TgPPARalpha/Tg-Sirt1 bigenic mice, microarray analyses were performed. The microarray analyses revealed that many ERR target genes were downregulated in Tg-PPARalpha and in Tg-Sirt1, and they were further downregulated in the Tg-PPARalpha/Tg-Sirt1 bigenic mice. Four groups of cardiac-specific transgenic mice were used for the study, i.e., control, PPARalpha, Sirt1 and PPARalpha/Sirt1. Hearts were dissected after 10-11 weeks of male FVB background transgenic mice. Total RNA was prepared from the hearts to conduct the microarray analyses.
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.