Product of the retinoblastoma tumor suppressor gene. It is a nuclear phosphoprotein hypothesized to normally act as an inhibitor of cell proliferation. Rb protein is absent in retinoblastoma cell lines. It also has been shown to form complexes with the adenovirus E1A protein, the SV40 T antigen, and the human papilloma virus E7 protein.

Synonyms: 0, p105 Rb Protein, Retinoblastoma Nuclear Phosphoprotein p105-Rb, p105-Rb Protein, Rb1 Gene Product, Rb Protein, Rb Gene Product, Retinoblastoma Protein, Retinoblastoma Nuclear Phosphoprotein p105 Rb