Recognition of epigenetic marks can be mediated by small modular protein units of ~50 amino acids called Plant Homeodomain (PHD) fingers. PHD fingers are zinc binding domains that have a Cys4-His-Cys3 motif and are found in more than 100 nuclEAr proteins that play a role in regulating chromatin.1 PHD domains often work with other protein regions, such as bromodomains and Tudor domains, to recognize post-translational modifications in many proteins.1 Ubiquitin-like with PHD and ring finger domains 1 (UHRF1) is a multidomain-containing nuclEAr protein known to bind chromatin and participate in the maintenance of DNA methylation.2,3 The SET and RING associated domain of UHRF1, also called the YDG motif, binds methyl cytosines, while trimethylated histone H3 lysine 9 (H3K9me3) and unmethylated histone H3 Arginine 2 (H3R2me0) are recognized by the tandem Tudor-like domains and the PHD domain, respectively.4,5,6,7,8,9 Some evidence suggests the tandem Tudor-like region and adjacent PHD domain may operate together to recognize H3K9me3.10 The combinatorial recognition of the histone tail region and hemi-methylated DNA functions to regulate gene silencing by directly interacting with DNA (cytosine-5)-methyltransferase 1.11,2,12 UHRF1 also posseses E3 ubiquitin ligase activity toward histone H3 and the tumor suppressor promyelocytic leukemia protein.7,13 This protein product contains the PHD finger region of UHRF1.Technical InformationSynonymsE3 Ubiquitin-protein Ligase UHRF1Inverted CCAAT Box Binding Protein of 90 kDaNuclEAr Protein 95RING Finger Protein 106Transcription Factor ICBP90Ubiquitin-like PHD and RING Finger Domain-containing Protein 1Purity95%Sourcerecombinant N-terminal GST-tagged protein expressed in E. coliMW35.5 kDaFormulation50 mM Tris, pH 8.0, containing 150 mM sodium chloride and 20% glycerolUniProt Accession Q96T88