TI  - The bZIP domains of  <prot>Fos</prot>  and  <prot>Jun</prot>  mediate a physical association with the
        <prot>TATA box-binding protein</prot>  .
PG  - 37-48
AB  -  <prot>Fos</prot>  and  <prot>Jun</prot>  oncoproteins form a complex that regulates transcription from
      promoters containing AP-1 binding sites. These two proteins, like other
      transcriptional activators, are likely to stimulate transcription through
      direct and/or indirect interactions with members of the basal
      transcriptional machinery. The ability of  <prot>c-Fos</prot>  and  <prot>c-Jun</prot>  proteins to
      interact directly with the   <prot>TATA box-binding protein</prot> (<prot>TBP</prot>)  , the general
      transcription factor required for initiating the assembly of transcription
      complexes, was investigated. Using co-immunoprecipitation and
      protein-protein association assays, we show that both  <prot>c-Fos</prot>  and  <prot>c-Jun</prot>  bind
      specifically and stably to   <prot>TBP</prot>   Mutational analysis demonstrates that both
      the basic region and leucine zipper domains of  <prot>c-Fos</prot>  and  <prot>c-Jun</prot>  are
      necessary and sufficient for stable association with   <prot>TBP</prot>  . A 51-residue
      region from the conserved C-terminal region of   <prot>TBP</prot>  , previously shown to be
      the binding site for the viral activator protein <prot>E1A</prot>, interacts with  <prot>c-Fos</prot> 
      and  <prot>c-Jun</prot>  proteins. We propose that  <prot>c-Fos</prot>  and  <prot>c-Jun</prot>  proteins function as
      transcriptional activators, in part by recruiting   <prot>TBP</prot>   to form complexes to
      initiate RNA synthesis.
AD  - Molecular Biology and Virology Laboratory, Salk Institute, San Diego, CA
