Analysis of Gal4-directed transcription activation using Tra1 mutants selectively defective for interaction with Gal4
Document Type
Journal ArticlePublication Date
2012-02-07Keywords
Binding SitesBiological Assay
DNA, Fungal
DNA-Binding Proteins
Fluorescence
Galactokinase
Galactose
Gene Expression Regulation, Fungal
Histone Acetyltransferases
Mutation
Promoter Regions, Genetic
Protein Binding
Saccharomyces cerevisiae
Saccharomyces cerevisiae Proteins
Trans-Activators
Transcription Factors
Transcriptional Activation
Genetics and Genomics
Metadata
Show full item recordAbstract
Promoter-specific transcriptional activators (activators) stimulate transcription through direct interactions with one or more components of the transcription machinery, termed the "target." The identification of direct in vivo targets of activators has been a major challenge. Previous studies have provided evidence that the Tra1 subunit of the yeast SAGA (Spt-Ada-Gcn5-acetyltransferase) complex is the target of the yeast activator Gal4. However, several other general transcription factors, in particular the mediator complex, have also been implicated as Gal4 targets. Here we perform a large-scale genetic screen to derive and characterize tra1 alleles that are selectively defective for interaction with Gal4 in vivo [Gal4 interaction defective (GID) mutants]. In contrast to WT Tra1, Tra1 GID mutants are not recruited by Gal4 to the promoter and cannot support Gal4-directed transcription, demonstrating the essentiality of the Gal4-Tra1 interaction. In yeast strains expressing a Tra1 GID mutant, binding of Gal4 to the promoter is unexpectedly also diminished, indicating that Gal4 and Tra1 bind cooperatively. Consistent with cooperative binding, we demonstrate that the Gal4-Tra1 interaction occurs predominantly on the promoter and not off DNA. Finally, we show that although Tra1 is targeted by other activators, these interactions are unaffected by GID mutations, revealing an unanticipated specificity of the Gal4-Tra1 interaction.Source
Ling Lin, Lynn Chamberlain, Lihua J. Zhu, and Michael R. Green. Analysis of Gal4-directed transcription activation using Tra1 mutants selectively defective for interaction with Gal4. Proc Natl Acad Sci U S A. 2012 Feb 7;109(6):1997-2002. Epub 2012 Jan 23. Link to article on publisher's siteDOI
10.1073/pnas.1116340109Permanent Link to this Item
http://hdl.handle.net/20.500.14038/43969PubMed ID
22308403Related Resources
Link to Article in PubMedRights
Publisher PDF posted as allowed by the publisher's author rights policy, http://www.pnas.org/site/misc/authorfaq.shtml.
ae974a485f413a2113503eed53cd6c53
10.1073/pnas.1116340109