DNA Methylation

Review of "L1 retrotransposition in neurons is modulated MeCP2" Nick Matthew Brandeis University November 6, 2012 What's covered in this presentation: Review of DNA methylation. DNMTs Methyl-CpG-binding proteins. MeCP2 Induced Pluripotent Stem Cells Retrotransposons, L1s and Environment Review of MeCP2 paper. Histone Modifications RNA Interference Chromatin Conformation A few epigenetic models covered in class ... Cytosine Methylation Cytosine In eukaryotes, DNA methylation only occurs on "CpG islands" How does DNA become methylated? Two classes of DNA methyltransferases (DNMTs) de novo maintenance Three possible de novo methylation mechanisms DNA Methylation and Gene Repression The methyl-CpG-binding family. MeCP2: A dynamic repressor of neuronal genes. L1 retrotransposition in neurons is modulated by MeCP2 Consequences of DNA Methylation: Transcription Repression Retrotransposons MeCP2 Mutations and Retts Syndrome Induced Pluripotent Stem Cells (iPSC) Environmental Influence on L1 Retrotransposons To Review... DNMTs methylate cytosines at CpG islands. These methylations recruit Methyl-CpG-binding proteins, repressing gene expression. Of these methyl binding proteins, mutations in MeCP2 have been shown to cause Retts syndrome. DNA Methylation Transposons Transposons are common in mammal genomes, but their function has historically been unclear. Recent research has shown that transposons are active in neuron cells, and are upregulated in mice in response to environmental stimuli. What's the relationship between MeCP2 and transposons?