DescriptionKey regulator of entry into cell division that acts as a tumor suppressor. Promotes G0-G1 transition when phosphorylated by CDK3/cyclin-C. Acts as a transcription repressor of E2F1 target genes. The underphosphorylated, active form of Rb1 interacts with E2F1 and represses its transcription activity, leading to cell cycle arrest. Directly involved in heterochromatin formation by maintaining overall chromatin structure and, in particular, that of constitutive heterochromatin by stabilizing histone methylation. Recruits and targets histone methyltransferases SUV39H1, SUV420H1 and SUV420H2, leading to epigenetic transcriptional repression. Controls histone H4 "Lys-20" trimethylation. Inhibits the intrinsic kinase activity of TAF1. Mediates transcriptional repression by SMARCA4/BRG1 by recruiting a histone deacetylase (HDAC) complex to the c-FOS promoter. In resting neurons, transcription of the c-FOS promoter is inhibited by BRG1-dependent recruitment of a p-Rb1/HDAC1 repressor complex. Upon calcium influx, Rb1 is dephosphorylated by calcineurin, which leads to release of the repressor complex (By similarity). In case of viral infections, interactions with SV40 large T antigen, HPV E7 protein or adenovirus E1A protein induce the disassembly of Rb1/E2F1 complex thereby disrupting Rb1"s activity. [UniProt]Application NotesTitration of the p-Rb1 antibody may be required due to differences in protocols and secondary/substrate sensitivity.ImmunogenThis p-Rb1 antibody was produced from rabbits immunized with a KLH conjugated synthetic phosphopeptide corresponding to amino acid residues surrounding pS811 of human Retinoblastoma.StorageAliquot the p-Rb1 antibody and store frozen at -20oC or colder.Avoid repeated freeze-thaw cycles. Related Products1. View all p-Rb1 antibodies