TATA-binding protein and the retinoblastoma gene product bind to overlapping epitopes on c-Myc and adenovirus E1A protein

Abstract

Using a protein binding assay, we show that the amino-teminal 204 amino acids of the c-Myc protein interact di y with a key component of the basal p tdon factor TFID, the TATA box-binding protein (TBP). Essentialy the same region of the c-Myc protein alo binds the product of the retinoblatoma gene, the RB protein. c-Myc protein communoprecipitates with TBP in lysates of mamma- Han cells, de that the proteins are also complexed in Wvo. A short peptide that spans the RB binding dte of the E7 protein of hum paplloma virus type 16 interferes with the binding ofc-Myc to TBP. The same peptide also blocks binding of adenovirus EIA protein to TBP, i that c-Myc and ElA bind to RB and TBP through overlapping epitopes. Furthermore, we show that binding of RB to ElA prevents associaion of ElA with TBP. Our data snggest that one of the fnctions of RB and RB-Uke proteins is to prevent interaction of viral and cellular oncoproteins, such as c-Myc and ElA, with TBP.