Regulated epigenetics

In higher eukaiyotes, most of the chromosomal DNA carries 5-methyl-cytidine residues located in CpG sequence motives. There is a close correlation between transcriptional inactivation and methylation. On the other hand, considerable evidence shows that regions of DNA that are actively engaged in transcription lack 5-methyl-cytidine nucleotides in CpG motivs. Hence DNA methylation is a means how cells regulate gene expression. DNA methylation which is catalyzed by DNA methyltransferases is the best characterized epigenetic mechanism. 

Mori T, Kim J, Yamano T, et al. Epigenetic up-regulation of C-C chemokine receptor 7 and C-X-C chemokine receptor 4 expression in melanoma cells. Cancer Res 2005 65 180-187. 

Biel M, Wascholowski V, Giannis A (2005) Epigenetics - an epicenter of gene regulation histones and histone-modifying enzymes. Angew Chem-Int Edit 44 3186-3216... 

Suuronen, T, Nuutinen, T, Ryhanen, T, Kaamiranta, K, and Salminen, A, 2007. Epigenetic regulation of clusterin/apolipoprotein J expression in retinal pigment epithelial cells. Biochem Biophys Res Commun 357, 397—401. 

Stryer, L., Berg, J.M. and Tymoczko, J.L. (2002). Biochemistry (5th ed.). W.H. Freeman, New York Turner, B.M. (2001). Chromatin and Gene Regulation — Molecular Mechanisms in Epigenetics. Blackwell Science, Oxford... 

Turner, B.M. (2001). Chromatin and Gene Regulation — Molecular Mechanisms in Epigenetics. Blackwell Science, Oxford... 

Figure 17.4. Epigenetics in the nervous system. Regulation occurs in response to synaptic inputs and/or other psychosocial-environmental stimuli. The external stimuli result in changes in the transcriptional profile of the neuron and eventually affects neural function(s). Many disorders of human cognition might involve dysfunction of epigenetic tagging. (See color insert.)...

Rice JC, Allis CD (2001) Histone methylation versus histone acetylation new insights into epigenetic regulation. Cutr Opin Cell Biol 13 263-273... 

Yang XJ, Seto E (2003) Collaborative spirit of histone deacetylases in regulating chromatin structure and gene expression. Curr Opin Genet Dev 13 143-153 Yoo CB, Jones PA (2006) Epigenetic therapy of cancer past, present and future. Nat Rev Drug Discov 5 37-50... 

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