Phospho-Rb (Ser807/811) (D9) rabbit mAb

Retinoblastoma protein (Rb, phospho Rb) is a tumor suppressor protein that is inactivated in a numbr of diverse cancers. The antiproliferative activity of Rb is mediated by its ability to inhibit the transcription of genes that are required for cell cycle progression. Rb contains conserved sites that are phosphorylated by cyclin-dependent kinases (CDKs). CDK phosphorylation typically promotes protein-protien interations through creation of a phospho-epitope that becomes structured upon binding its target. However Rb phosphorylation distrupts interactions with its binding partners. When it is phosphorylated, phospho Rb is inactivated and allows execcisve cell growth that is seen in cancer cells. Sixteen potential sites for CDK-mediated phosphorylation exist in Rb and twelve of these sites have been shown to be phosphorylated in vivo.