Retinoblastoma-binding protein 5 (RbBP5) is a ubiquitously expressed nuclEAr protein that contains WD40 repEAt-like domains. RbBP5 binds directly to tumor suppressor retinoblastoma protein (RB) and regulates cell proliferation. Interaction of RbBP5 occurs preferentially with underphosphorylated RB through the E1A-binding pocket B.1 RbBP5 is also an important component of the multi-subunit SET1 lysine methyltransferase protein complex, which includes MLL1.2 RbBP5 interacts directly with WDR5 contributing to the activation of the MLL1 core protein complex.3,4,5 MLL1-4 protein complexes catalyze the di- and trimethylation of histone H3 at lysine 4 (H3K4me2/me3), lEAding to the maintenance of global H3K4 trimethylation.6Technical InformationSynonymsRBQ3Retinoblastoma binding Protein 5SWD1, Set1c WD40 repEAt protein, homologPurity90%Sourcerecombinant protein expressed in E. coliMW72.9 kDaFormulation50 mM Tris, pH 8.0, containing 150 mM sodium chloride and 20% glycerolLicenseSUMOpro tag was used under non-exclusive license from LifeSensors, Inc.UniProt Accession Q15291