This entry includes UHRF1/2 from animals and ORTHRUS 1-5 from Arabidopsis. They are ubiquitin-like proteins with PHD and RING finger domains. UHRF1, also known as ICBP90, is a transcription and cell cycle regulator and a methyl K9 H3-specific binding protein []. UHRF2 is a ubiquitin E3 ligase for cell cycle proteins, such as CCND1 and CCNE1 []. It can also act as a SUMO E3 ligase for ZNF131 []. This family also includes UHRF1-like protein from Cryptococcus neoformans, which binds hemimethylated DNA and is involved in DNA methylation maintenance. Unlike the human orthologue, UHRF1-like lacks the Tudor H3K9me reader and RING E3 ligase domains found in its human ortholog [].In plants, ORTHRUS family members are E3 ligases mediating DNA methylation status in vivo. ORTH1-ORTH5 are predicted to encode proteins that contain one plant homeodomain (PHD), two really interesting new gene (RING) domains, and one set ring associated (SRA) domain [].
