C20orf20, also named as MRG/MORF4L-binding protein or Up-regulated in colon cancer 4 (Urcc4), is a 204 amino acid protein, which belongs to the EAF7 family. C20orf20 localizes in the nucleus and is a Component of the NuA4 histone acetyltransferase (HAT) complex which is involved in transcriptional activation of select genes principally by acetylation of nucleosomal histones H4 and H2A. This modification may both alter nucleosome - DNA interactions and promote interaction of the modified histones with other proteins which positively regulate transcription. This complex may be required for the activation of transcriptional programs associated with oncogene and proto-oncogene mediated growth induction, tumor suppressor mediated growth arrest and replicative senescence, apoptosis, and DNA repair. C20orf20 is modified through phosphorylation and acetylation, so the molecular weight of C20orf20 might be 25-30 kDa.