![]() These inactive ETF-binding sites became functional when placed upstream of the EGFR promoter whose own ETF-binding sites were removed. ETF stimulated in vitro transcription from several promoters without TATA boxes but had little or no effect on TATA box-containing promoters even though they had strong ETF-binding sites. ETF also binds to TATA boxes but with a lower affinity. Here, we show that ETF recognizes various GC-rich sequences including stretches of deoxycytidine or deoxyguanosine residues and GC boxes with similar affinities. Transcription factor ETF stimulates the expression of the epidermal growth factor receptor (EGFR) gene which does not have a TATA box in the promoter region. Nuclear factor ETF specifically stimulates transcription from promoters without a TATA box. Copyright © 2014, American Society for Microbiology. Our results also explain why yeast TBP derivatives defective for TATA binding appear defective in activated transcription. Our results are consistent with the model that sequence-specific TBP-DNA contacts are not important at yeast TATA-less genes and suggest that other general transcription factors or coactivator subunits are responsible for recognition of TATA-less promoters. TBP binds several TATA-less promoters with apparent high affinity, but our results suggest that this binding is not important for transcription activity. Both in vivo and in vitro, many of these mutations are specifically defective for transcription of two TATA-containing genes with only minor defects in transcription of two TATA-less, TFIID-dependent genes. We generated a set of mutations in the yeast TBP DNA binding surface and found that most support growth of yeast. Transcription factor IID (TFIID), the TBP-containing coactivator that functions at most TATA-less genes, recognizes short sequence-specific promoter elements in metazoans, but analogous promoter elements have not been identified in Saccharomyces cerevisiae. While the TBP- TATA interaction is critical for transcription at TATA-containing promoters, it has been unclear whether TBP sequence-specific DNA contacts are required for transcription at TATA-less genes. Most RNA polymerase (Pol) II promoters lack a TATA element, yet nearly all Pol II transcription requires TATA binding protein (TBP). Kamenova, Ivanka Warfield, Linda Hahn, Steven Mutations on the DNA binding surface of TBP discriminate between yeast TATA and TATA-less gene transcription. ![]()
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