Identification of a 60-kilodalton Rb-binding protein, RBP60, that allows the Rb-E2F complex to bind DNA.
Several reports have indicated that the product of the retinoblastoma gene (Rb) complexes with the transcription factor E2F. We present evidence that the DNA-binding of the Rb-E2F complex involves another cellular factor. Addition of Rb to purified preparations of E2F does not generate an Rb-E2F complex that can bind DNA, and in fact, we see an inhibition of the DNA-binding ability of E2F. On the other hand, addition of Rb to cruder preparations of E2F results in the formation of an Rb-E2F complex (E2Fr) that can bind DNA and produces a distinct complex in gel retardation assays. We have identified and purified a 60-kDa protein that allows the Rb-E2F complex to bind DNA, and we show that this 60-kDa protein exerts its effect by directly interacting with Rb.
Ray
S K
SK
Department of Biochemistry (M/C 536), University of Illinois, Chicago 60680.
Arroyo
M
M
Bagchi
S
S
Raychaudhuri
P
P
D000818:Animals; D001483:Base Sequence; D015153:Blotting, Western; D002352:Carrier Proteins; D018797:Cell Cycle Proteins; D004247:DNA / Q000378:metabolism; D004268:DNA-Binding Proteins; D050684:E2F Transcription Factors; D004591:Electrophoresis, Polyacrylamide Gel; D006367:HeLa Cells; D006801:Humans; D007739:L Cells; D051379:Mice; D008969:Molecular Sequence Data; D011485:Protein Binding; D011506:Proteins / Q000378:metabolism*; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000378:metabolism; D016160:Retinoblastoma Protein / Q000378:metabolism*; D056465:Retinoblastoma-Binding Protein 1; D050680:Transcription Factor DP1; D014157:Transcription Factors / Q000378:metabolism*
C533431:Arid4a protein, mouse; D002352:Carrier Proteins; D018797:Cell Cycle Proteins; D004268:DNA-Binding Proteins; D050684:E2F Transcription Factors; D011506:Proteins; D011993:Recombinant Fusion Proteins; D016160:Retinoblastoma Protein; D056465:Retinoblastoma-Binding Protein 1; D050680:Transcription Factor DP1; D014157:Transcription Factors; D004247:DNA