Distribution, silencing potential and evolutionary impact of promoter DNA methylation in the human g

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Distribution, silencing potential and
evolutionary impact of promoter DNA methylation
in the human genome

• Weber M. et al. (2007) Nature Genetics 39,
  457-466

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Searching in right place and right manner
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Profiling of DNA methylation
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(No Transcript)
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Division of Promoters
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Differential methylation of promoter classes

• Hypermethylated 5mC log2 ratio gt 0.4

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Reconfirmation with bisulfite sequencing
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Methylation and decrease in transcription
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Polymerase Occupancy in relation to DNA
methylation
Active as well As Non-active
Active less 5mC Non-active more 5mC
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H3K4 Enrichment transcriptionally active
chromatin
Divison of Inactive
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Somatic vs. germ cells
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Somatic vs. germ cells
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Hypermethylation and Functional categories
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Evolutionary Implications
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Summary
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Conclusions

• High CpG promoters are undermethylated and
  promoters with low CpG content are
  hypermethylated.
• Relation between CpG methylation and
  transcription repression is still confusing.
• Methylation certainly play a role in shutting
  germ-cell specific genes in somatic cells