Ribosomal RNA-processing protein 8 (RRP8)

Essential part of the eNoSC (energy-dependent nucleolar silencing) complex, a complex that mediates silencing of rDNA in response to intracellular energy status and functions by recruiting histone-modifying enzymes. The eNoSC complex is able to sense the energy status of mobile: upon glucose starvation, elevation of NAD(+)/NADP(+) ratio activates SIRT1, resulting in histone H3 deacetylation followed by dimethylation of H3 at'Lys- 9' (H3K9me2) by SUV39H1 and the formation of silent chromatin in the rDNA locus.

In the complicated, RRP8 binds to H3K9me2 and probably functions as a methyltransferase. Its substrates are however unknown.