Project description:We compared gene expression changes in the cerebellum of mice lacking MeCP2 (Mecp2-null) and mice overexpressing MeCP2 (MECP2-transgenic). A group of postnatal neurodevelopmental disorders collectively referred to as MeCP2 disorders are caused by aberrations in the gene encoding methyl-CpG-binding protein 2 (MECP2). Loss of MeCP2 function causes Rett syndrome (RTT), whereas increased copy number of the gene causes MECP2 duplication or triplication syndromes. MeCP2 acts as a transcriptional repressor, however the gene expression changes observed in the hypothalamus of MeCP2 disorder mouse models suggest that MeCP2 can also upregulate gene expression. To determine if this dual role of MeCP2 extends beyond the hypothalamus, we studied gene expression patterns in the cerebellum of Mecp2-null and MECP2-Tg mice, modeling RTT and MECP2 duplication syndrome, respectively. We found that abnormal MeCP2 dosage causes alterations in the expression of hundreds of genes in the cerebellum. The majority of genes were upregulated in MECP2-Tg mice and downregulated in Mecp2-null mice, consistent with a role for MeCP2 as a modulator that can both increase and decrease gene expression. Interestingly, many of the genes altered in the cerebellum, particularly those increased by the presence of MeCP2 and decreased in its absence, were similarly altered in the hypothalamus. Keywords: Comparison of cerebellar gene expression data between Mecp2-null mice and Mecp2-transgenic mice
Project description:We compared gene expression changes in the cerebellum of mice lacking MeCP2 (Mecp2-null) and mice overexpressing MeCP2 (MECP2-transgenic). A group of postnatal neurodevelopmental disorders collectively referred to as MeCP2 disorders are caused by aberrations in the gene encoding methyl-CpG-binding protein 2 (MECP2). Loss of MeCP2 function causes Rett syndrome (RTT), whereas increased copy number of the gene causes MECP2 duplication or triplication syndromes. MeCP2 acts as a transcriptional repressor, however the gene expression changes observed in the hypothalamus of MeCP2 disorder mouse models suggest that MeCP2 can also upregulate gene expression. To determine if this dual role of MeCP2 extends beyond the hypothalamus, we studied gene expression patterns in the cerebellum of Mecp2-null and MECP2-Tg mice, modeling RTT and MECP2 duplication syndrome, respectively. We found that abnormal MeCP2 dosage causes alterations in the expression of hundreds of genes in the cerebellum. The majority of genes were upregulated in MECP2-Tg mice and downregulated in Mecp2-null mice, consistent with a role for MeCP2 as a modulator that can both increase and decrease gene expression. Interestingly, many of the genes altered in the cerebellum, particularly those increased by the presence of MeCP2 and decreased in its absence, were similarly altered in the hypothalamus. Keywords: Comparison of cerebellar gene expression data between Mecp2-null mice and Mecp2-transgenic mice Total cerebellar RNA samples were collected from Mecp2-null male mice (n=5), MECP2-transgenic male mice (n=5), and their wild type male littermates at 6 weeks of age (n=5 for each group).
Project description:We created mice, which are deficient for Myc specifically in cardiac myocytes by crossing crossed Myc-floxed mice (Mycfl/fl) and MLC-2VCre/+ mice. Serial analysis of earlier stages of gestation revealed that Myc-deficient mice died prematurely at E13.5-14.5. Morphological analyses of E13.5 Myc-null embryos showed normal ventricular size and structure; however, decreased cardiac myocyte proliferation and increased apoptosis was observed. BrdU incorporation rates were also decreased significantly in Myc-null myocardium. Myc-null mice displayed a 3.67-fold increase in apoptotic cardiomyocytes by TUNEL assay. We examined global gene expression using oligonucleotide microarrays. Numerous genes involved in mitochondrial death pathways were dysregulated including Bnip3L and Birc2. Keywords: wildtype vs Myc-null
Project description:MECP2-R270X transgenic mice (TG) and MECP2-G273X TG mice were generated in the Zoghbi Lab. These mice express the respective truncated form of MeCP2 tagged with GFP at the C-terminus from a transgenic human PAC containing all known regulatory sequences. These transgenes were maintained on a wild-type pure FVB background. For experiments each transgenic line was crossed by Mecp2 null mice (Mecp2 tm1.1Bird) on a pure 129SvEv background and the resulting male F1 hybrid progeny (FVB;129SvEv) that lacked endogenous MeCP2 expression but expressed either transgene (Mecp2 -/y; MECP2-R270X TG or Mecp2-/y; MECP2-G273X TG) were used for ChIP-Seq analysis. Whole brain from either the R270X mice (Mecp2 -/y; MECP2-R270X TG) or the G273X mice (Mecp2 -/y; MECP2-G273X TG) was formaldehyde crosslinked and purified chromatin was immunoprecipitated with anti-GFP antibody (Abcam ab6556). 2 samples: R270X (Mecp2 -/y; MECP2-R270X TG) and G273X (Mecp2 -/y; MECP2-G273X TG) both on an F1 (FVB;129SvEv) hybrid background
Project description:MECP2-R270X transgenic mice (TG) and MECP2-G273X TG mice were generated in the Zoghbi Lab. These mice express the respective truncated form of MeCP2 tagged with GFP at the C-terminus from a transgenic human PAC containing all known regulatory sequences. These transgenes were maintained on a wild-type pure FVB background. For experiments each transgenic line was crossed by Mecp2 null mice (Mecp2 tm1.1Bird) on a pure 129SvEv background and the resulting male F1 hybrid progeny (FVB;129SvEv) that lacked endogenous MeCP2 expression but expressed either transgene (Mecp2 -/y; MECP2-R270X TG or Mecp2-/y; MECP2-G273X TG) were used for ChIP-Seq analysis. Whole brain from either the R270X mice (Mecp2 -/y; MECP2-R270X TG) or the G273X mice (Mecp2 -/y; MECP2-G273X TG) was formaldehyde crosslinked and purified chromatin was immunoprecipitated with anti-GFP antibody (Abcam ab6556).
Project description:We compared gene expression changes in the hypothalamus of mice lacking MeCP2 (Mecp2-null) and mice overexpressing MeCP2 (MECP2-transgenic). Mutations in the gene encoding the transcriptional repressor methyl-CpG binding protein 2 (MeCP2) cause the neurodevelopmental disorder Rett syndrome. Loss of function as well as increased dosage of MECP2 gene cause a host of neuropsychiatric disorders. To explore the molecular mechanism(s) underlying these disorders, we examined gene expression patterns in the hypothalamus of mice that either lack or overexpress MeCP2. In both models, MeCP2 dysfunction induced changes in the expression levels of thousands of genes, but surprisingly the majority of genes (~85%) appeared to be activated by MeCP2. We selected six genes and confirmed that MeCP2 binds to their promoters. Furthermore, we showed that MeCP2 associates with the transcriptional activator CREB1 at the promoter of an activated target but not a repressed target. These studies suggest that MeCP2 regulates the expression of a wide range of genes in the hypothalamus and that it can function as both an activator and repressor of transcription. Total hypothalamic RNA samples were collected from Mecp2-null male mice (n=4), MECP2-transgenic male mice (n=4), and their wild type male littermates at 6 weeks of age (n=4 for each group).