Regulation of transcription by the retinoblastoma protein.

The product of the retinoblastoma gene (RB1) is believed to function as a negative regulator of cell growth. Recent experimental results suggest that RB1 may exert its growth-suppressing activity by regulating the transcription of a variety of growth-related genes, including FOS, MYC, and TGFBI. A series of biochemical and molecular analyses suggest that RB1 indirectly affects gene expression via cell-cycle-regulated interactions with transcription factors, such as E2F and SPI. Determination of the mechanisms regulating such protein-protein interactions and the identification of additional targets of RB1 function will provide vital insights into the role of this tumor-suppressor gene in mammalian cell proliferation.