A negative regulator of the CELL CYCLE that undergoes PHOSPHORYLATION by CYCLIN-DEPENDENT KINASES. It contains a conserved pocket region that binds E2F4 TRANSCRIPTION FACTOR and interacts with viral ONCOPROTEINS such as POLYOMAVIRUS TUMOR ANTIGENS; ADENOVIRUS E1A PROTEINS; and PAPILLOMAVIRUS E7 PROTEINS.

Synonyms: p107 Tumor Suppressor Protein, 0, Retinoblastoma Like Protein 1, Retinoblastoma Like Protein p107, p107, Retinoblastoma-Like Protein, Retinoblastoma-Like Protein p107, Retinoblastoma-Like Protein 1, RBL1 Protein