- THIS ARTICLE
- Full Text
- Full Text (PDF)
- Alert me when this article is cited
- Alert me if a correction is posted
- SERVICES
- Email this article to a friend
- Similar articles in this journal
- Similar articles in PubMed
- Alert me to new issues of the journal
- Download to citation manager
- Reprints & Permissions
- CITING ARTICLES
- Citing Articles via HighWire
- Citing Articles via Google Scholar
- GOOGLE SCHOLAR
- Articles by Laprade, L.
- Articles by Winston, F.
- Search for Related Content
- PUBMED
- PubMed Citation
- Articles by Laprade, L.
- Articles by Winston, F.
Genetics, Vol. 177, 2007-2017, December 2007, Copyright © 2007
doi:10.1534/genetics.107.081976
Characterization of New Spt3 and TATA-Binding Protein Mutants of Saccharomyces cerevisiae: Spt3–TBP Allele-Specific Interactions and Bypass of Spt8
Lisa Laprade, David Rose1 and Fred Winston2
Department of Genetics, Harvard Medical School, Boston, MA 02115
2 Corresponding author: Department of Genetics, Harvard Medical School, 77 Ave. Louis Pasteur, Boston, MA 02115.
E-mail: winston{at}genetics.med.harvard.edu
The Spt-Ada-Gcn5-acetyltransferase (SAGA) complex of Saccharomyces cerevisiae is a multifunctional coactivator complex that has been shown to regulate transcription by distinct mechanisms. Previous results have shown that the Spt3 and Spt8 components of SAGA regulate initiation of transcription of particular genes by controlling the level of TATA-binding protein (TBP/Spt15) associated with the TATA box. While biochemical evidence exists for direct Spt8–TBP interactions, similar evidence for Spt3–TBP interactions has been lacking. To learn more about Spt3–TBP interactions in vivo, we have isolated a new class of spt3 mutations that cause a dominant-negative phenotype when overexpressed. These mutations all cluster within a conserved region of Spt3. The isolation of extragenic suppressors of one of these spt3 mutations has identified two new spt15 mutations that show allele-specific interactions with spt3 mutations with respect to transcription and the recruitment of TBP to particular promoters. In addition, these new spt15 mutations partially bypass an spt8 null mutation. Finally, we have examined the level of SAGA–TBP physical interaction in these mutants. While most spt3, spt8, and spt15 mutations do not alter SAGA–TBP interactions, one spt3 mutation, spt3-401, causes a greatly increased level of SAGA–TBP physical association. These results, taken together, suggest that a direct Spt3–TBP interaction is required for normal TBP levels at Spt3-dependent promoters in vivo.
This article has been cited by other articles:
 |
|
 |
|
  D. Helmlinger, S. Marguerat, J. Villen, S. P. Gygi, J. Bahler, and F. Winston The S. pombe SAGA complex controls the switch from proliferation to sexual differentiation through the opposing roles of its subunits Gcn5 and Spt8 Genes & Dev., November 15, 2008; 22(22): 3184 - 3195. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
N. Mohibullah and S. Hahn Site-specific cross-linking of TBP in vivo and in vitro reveals a direct functional interaction with the SAGA subunit Spt3 Genes & Dev., November 1, 2008; 22(21): 2994 - 3006. [Abstract] [Full Text] [PDF]
|
|