Setdb1-mediated histone H3K9 hypermethylation in neurons worsens the neurological phenotype of Mecp2-deficient mice
| Autor: | Yin Guo, Schahram Akbarian, Anouch Matevossian, Yan Jiang |
|---|---|
| Rok vydání: | 2011 |
| Předmět: |
Male
congenital hereditary and neonatal diseases and abnormalities Methyl-CpG-Binding Protein 2 Genes myc Mice Transgenic tau Proteins Rett syndrome Biology Methylation Article Chromatin remodeling MECP2 Histones Mice Mice Neurologic Mutants Cellular and Molecular Neuroscience Histone methylation medicine Animals Protein Methyltransferases Epigenetics Cerebral Cortex Mice Knockout Neurons Pharmacology Behavior Animal SETDB1 Gene Brain Histone-Lysine N-Methyltransferase medicine.disease Chromatin Mice Inbred C57BL Phenotype Histone biology.protein Cancer research Female Locomotion |
| Zdroj: | Neuropharmacology. 60:1088-1097 |
| ISSN: | 0028-3908 |
| Popis: | Rett syndrome (RTT, OMIM # 312750), a neurodevelopmental disorder of early childhood, is primarily caused by mutations in the gene encoding methyl-CpG-binding protein 2 (MECP2). Various molecular functions have been ascribed to MECP2, including the regulation of histone modifications associated with repressive chromatin remodeling, but the role of these mechanisms for the pathophysiology of RTT remains unclear. Here, we explore whether or not neuronal expression of the histone H3-lysine 9 specific methyl-transferase, Setdb1 (Set domain, bifurcated 1)/Eset/Kmt1e, which is normally present only at low levels in differentiated neurons, rescues the RTT-like phenotype of Mecp2-deficient mice. A myc-tagged Setdb1 cDNA was expressed through the tau locus for ubiquitous expression in CNS neurons, or under control of the calcium/calmodulin-dependent protein kinase II (CK) promoter to selectively target postmitotic neurons in forebrain. However, the CK-Setdb1 transgene lead to an enhanced neurological deficit, and the tauSetdb1 allele further shortened life span of mice with a brain-wide deletion of Mecp2 during prenatal development. In contrast, no neurological deficits or premature death was observed in CK-Setdb1 and tauSetdb1 mice expressing wildtype Mecp2. However, levels of trimethylated H3K9 at pericentromeric repeats were fully maintained in differentiated neurons from symptomatic Mecp2 null mutant mice. Based on these results, we draw two conclusions: First, neuronal chromatin in RTT brain is not affected by a generalized deficit in H3K9 trimethylation. Second, artificial up-regulation of this repressive chromatin mark via Setdb1 gene delivery specifically to neurons is harmful for the Mecp2-deficient brain. This article is part of a Special Issue entitled 'Trends in neuropharmacology: in memory of Erminio Costa'. |
| Databáze: | OpenAIRE |
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