Rb Adenovirus

The retinoblastoma susceptibility protein Rb is a 110 kDa phosphorylated protein. Like p53, Rb p110 is an anti-oncogene that is subject to inactivation by either mutation or by binding to certain DNA tumor virus-encoded proteins. Rb binds to and regulates transcription factors involved in cell cycle regulation, including the E2F family. Two Rb related proteins, p107 and p130, also function to regulate specific members of the E2F transcription factor family. Binding and inactivation of E2F proteins by Rb is regulated by cyclin dependent kinase-mediated phosphorylation