Transcription of rRNA genes is controlled by epigenetic activation and repression (reviewed in McStay and Grummt 2008, Goodfellow and Zomerdijk 2012, Grummt and Langst 2013). About half of the roughly 400 rRNA genes are expressed and these have the modifications of active chromatin: unmethylated DNA and acetylated histones. Repressed genes generally have methylated DNA and histone H3 methylated at lysine-9. Regulators of repression include the eNoSC complex, SIRT1, and the NoRC complex.
|GO Biological Process||negative regulation of gene expression, epigenetic (0045814)|
|18616426||The epigenetics of rRNA genes: from molecular to chromosome biology||Annu Rev Cell Dev Biol||2008|
|23150253||Basic mechanisms in RNA polymerase I transcription of the ribosomal RNA genes||Subcell. Biochem.||2012|
|23063748||Epigenetic control of RNA polymerase I transcription in mammalian cells||Biochim. Biophys. Acta||2013|