Project description:To confirm the mechanism of miR-29a in liver fibrosis healing, we have employed whole genome microarray expression profiling as a discovery platform to identify genes. CCl4 and TAA liver fibrosis model mouse were used for this experiment. After five weeks liver fibrosis induction period, mouse have been observed for one week (1w) or two weeks (2w) and negative control nucleotide (N.C) or miR-29a were injected every 3 days on this period. We used CCl4 1w N.C (n = 1), 1w miR-29a (n = 1), 2w N.C (n = 1), 2w miR-29a (n = 1), and also used TAA model mouse (total n = 8) liver samples for microarray analysis. We can get only one gene (PDGF-c) as a target of miR-29a which relate to liver fibrosis and down-regulated more than 1.5 times in common miR-29a injected group than N.C group. CCl4 and TAA liver fibrosis model mouse were used for this experiment. After five weeks liver fibrosis induction period, mouse have been obserbed for one week (1w) or two weeks (2w) and negative control nucleotide (N.C) or miR-29a were injected every 3 days on this period. We used CCl4 1w N.C (n = 1), 1w miR-29a (n = 1), 2w N.C (n = 1), 2w miR-29a (n = 1), and also used TAA model mouse (total n = 8) liver samples for microarray analysis.
Project description:To confirm the mechanism of miR-29a in liver fibrosis healing, we have employed whole genome microarray expression profiling as a discovery platform to identify genes. CCl4 and TAA liver fibrosis model mouse were used for this experiment. After five weeks liver fibrosis induction period, mouse have been observed for one week (1w) or two weeks (2w) and negative control nucleotide (N.C) or miR-29a were injected every 3 days on this period. We used CCl4 1w N.C (n = 1), 1w miR-29a (n = 1), 2w N.C (n = 1), 2w miR-29a (n = 1), and also used TAA model mouse (total n = 8) liver samples for microarray analysis. We can get only one gene (PDGF-c) as a target of miR-29a which relate to liver fibrosis and down-regulated more than 1.5 times in common miR-29a injected group than N.C group.
Project description:Visual cortical circuits show profound plasticity during early life and are later stabilized by molecular "brakes" limiting excessive circuit rewiring beyond a critical period. How the appearance of these factors is coordinated during the transition from development to adulthood remains unknown. We analyzed the role of miR-29a, a miRNA targeting factors involved in several important pathways for plasticity such as extracellular matrix and chromatin regulation. We found that visual cortical miR-29a expression in the visual cortex dramatically increases with age, but it is not experience-dependent. Precocious high levels of miR-29a induced by targeted intracortical injections of a miR-29a mimic blocked ocular dominance plasticity and caused an early appearance of perineuronal nets. Conversely, inhibition of miR-29a in adult mice using LNA antagomirs activated ocular dominance plasticity, reduced perineuronal net intensity and number, and changed their chemical composition restoring permissive low chondroitin 4-O-sulfation levels characteristic of juvenile mice. Activated adult plasticity had the typical functional and proteomic signature of juvenile plasticity. Transcriptomic and proteomic studies indicated that miR-29a manipulation regulates the expression of plasticity factors acting at different cellular levels, from chromatin regulation to synaptic organization and extracellular matrix remodeling. Intriguingly, the projection of miR-29a regulated gene dataset onto cell-specific transcriptomes revealed that parvalbumin-positive interneurons and oligodendrocytes were the most affected cells. Overall, miR29a is a master regulator of the age-dependent plasticity brakes promoting stability of visual cortical circuits.
Project description:Visual cortical circuits show profound plasticity during early life and are later stabilized by molecular "brakes" limiting excessive circuit rewiring beyond a critical period. How the appearance of these factors is coordinated during the transition from development to adulthood remains unknown. We analyzed the role of miR-29a, a miRNA targeting factors involved in several important pathways for plasticity such as extracellular matrix and chromatin regulation. We found that visual cortical miR-29a expression in the visual cortex dramatically increases with age, but it is not experience-dependent. Precocious high levels of miR-29a induced by targeted intracortical injections of a miR-29a mimic blocked ocular dominance plasticity and caused an early appearance of perineuronal nets. Conversely, inhibition of miR-29a in adult mice using LNA antagomirs activated ocular dominance plasticity, reduced perineuronal net intensity and number, and changed their chemical composition restoring permissive low chondroitin 4-O-sulfation levels characteristic of juvenile mice. Activated adult plasticity had the typical functional and proteomic signature of juvenile plasticity. Transcriptomic and proteomic studies indicated that miR-29a manipulation regulates the expression of plasticity factors acting at different cellular levels, from chromatin regulation to synaptic organization and extracellular matrix remodeling. Intriguingly, the projection of miR-29a regulated gene dataset onto cell-specific transcriptomes revealed that parvalbumin-positive interneurons and oligodendrocytes were the most affected cells. Overall, miR29a is a master regulator of the age-dependent plasticity brakes promoting stability of visual cortical circuits.
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:miR-29a/b1 was reported to be involved in the regulation of reproductive function in female mice, but the underlying molecular mechanisms were not clear. In this study, female mice lacking miR-29a/b1 showed a delay in vaginal opening, irregular estrus cycles, ovulation disorder and infertility. However, the development of egg was normal in mutant mice and the ovulation disorder could be rescued by the superovulation treatment. The plasma level of luteinizing hormone (LH) was significantly lower in the mutant mice. Using iTRAQ coupled with LC-MS/MS, we found that the deficiency of miR-29a/b1 in mice resulted in an abnormal expression of a number of proteins involved in vesicular transport and secretion in the pituitary gland. The miR-29a/b1 targeting gene Dnmt3a and Hdac4 were up-regulated in the pituitary of miR-29a/b1 knockout mice suggesting that these two epigenetic writers may be the upstream causes for these phenotype changes due to miR-29a/b1 deficiency. These findings demonstrated that miR-29a/b1 is indispensable for the function of the reproductive axis through regulating LH secretion in the pituitary gland.
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:Sex differences in liver gene expression are dictated by sex-differences in circulating growth hormone (GH) profiles. Presently, the pituitary hormone dependence of mouse liver gene expression was investigated on a global scale to discover sex-specific early GH response genes that might contribute to sex-specific regulation of downstream GH targets and to ascertain whether intrinsic sex-differences characterize hepatic responses to plasma GH stimulation. RNA expression analysis using 41,000-feature microarrays revealed two distinct classes of sex-specific mouse liver genes: genes subject to positive regulation (class-I) and genes subject to negative regulation by pituitary hormones (class-II). Genes activated or repressed in hypophysectomized (Hypox) mouse liver within 30-90min of GH pulse treatment at a physiological dose were identified as direct targets of GH action (early response genes). Intrinsic sex-differences in the GH responsiveness of a subset of these early response genes were observed. Notably, 45 male-specific genes, including five encoding transcriptional regulators that may mediate downstream sex-specific transcriptional responses, were rapidly induced by GH (within 30min) in Hypox male but not Hypox female mouse liver. The early GH response genes were enriched in 29 male-specific targets of the transcription factor Mef2, whose activation in hepatic stellate cells is associated with liver fibrosis leading to hepatocellular carcinoma, a male-predominant disease. Thus, the rapid activation by GH pulses of certain sex-specific genes is modulated by intrinsic sex-specific factors, which may be associated with prior hormone exposure (epigenetic mechanisms) or genetic factors that are pituitary-independent, and could contribute to sex-differences in predisposition to liver cancer or other hepatic pathophysiologies.