Your browser version may not work well with NCBI's Web applications. More information here...
1: Genes Dev. 2008 Nov 1;22(21):2994-3006.
Related Articles, Links
Click here to read Click here to read
Site-specific cross-linking of TBP in vivo and in vitro reveals a direct functional interaction with the SAGA subunit Spt3.

Mohibullah N, Hahn S.

Fred Hutchinson Cancer Research Center, Seattle, Washington 98109, USA.

The TATA-binding protein (TBP) is critical for transcription by all three nuclear RNA polymerases. In order to identify factors that interact with TBP, the nonnatural photoreactive amino acid rho-benzoyl-phenylalanine (BPA) was substituted onto the surface of Saccharomyces cerevisiae TBP in vivo. Cross-linking of these TBP derivatives in isolated transcription preinitiation complexes or in living cells reveals physical interactions of TBP with transcriptional coregulator subunits and with the general transcription factor TFIIA. Importantly, the results show a direct interaction between TBP and the SAGA coactivator subunits Spt3 and Spt8. Mutations on the Spt3-interacting surface of TBP significantly reduce the interaction of TBP with SAGA, show a corresponding decrease in transcription activation, and fail to recruit TBP to a SAGA-dependent promoter, demonstrating that the direct interaction of these factors is important for activated transcription. These results prove a key prediction of the model for stimulation of transcription at SAGA-dependent genes via Spt3. Our cross-linking data also significantly extend the known surfaces of TBP that directly interact with the transcriptional regulator Mot1 and the general transcription factor TFIIA.

Publication Types:
PMID: 18981477 [PubMed - in process]

PMCID: PMC2577793 [Available on 2009/05/01]