Rb (pS780) Mouse, PE, Clone: J146-35, BD

Description

• The retinoblastoma gene product (Rb) is well known as a tumor suppressor and is either absent or mutated in many human tumors
• Retrovirus-mediated gene transfer of the wild-type Rb gene into several Rb mutant neoplastic cell lines suppresses their tumorgenicity
• Rb is a 110kDa nuclear phosphoprotein that undergoes differential phosphorylation during the cell cycle
• During G1 phase, Rb is predominantly in a hypophosphorylated state
• It becomes increasingly phosphorylated throughout the cell cycle until late mitosis, when substantial dephosphorylation occurs
• Hypophosphorylated Rb interacts with a number of cellular proteins including the E2F transcription factor, several cyclins, RBP-1, RBP-2, c-Abl, c-myc, N-myc, and p46
• Phosphorylation of Rb at various sites, by Cyclin-dependent protein kinases, inhibits the binding of Rb to these proteins
• Rb is thought to mediate its effects, in part, via the repression of genes required for proliferation
• For example, Rb is specifically recruited to promoters containing E2F sites and actively represses E2F mediated transcription
• Rb also stimulates the activity of other transcription factors, although the mechanisms are less clearly defined
• Thus, Rb appears to regulate transcription in its aim to control cell growth
• The J146-35 monoclonal antibody recognizes Rb phosphorylated at serine 780 (pS780), which affects Rb binding to E2F
• The orthologous phosphorylation sites in mouse and rat Rb are serines 773 and 751, respectively
• Intracellular Staining