title: Analysis of Spt7 function in the Saccharomyces cerevisiae SAGA coactivator complex.
abstract: The Saccharomyces cerevisiae SAGA complex is required for the normal transcription of a large number of genes. Complex integrity depends on three core subunits, Spt7, Spt20, and Ada1. We have investigated the role of Spt7 in the assembly and function of SAGA. Our results show that Spt7 is important in controlling the levels of the other core subunits and therefore of SAGA. In addition, partial SAGA complexes containing Spt7 can be assembled in the absence of both Spt20 and Ada1. Through biochemical and genetic analyses of a series of spt7 deletion mutants, we have identified a region of Spt7 required for interaction with the SAGA component Spt8. An adjacent Spt7 domain was found to be required for a processed form of Spt7 that is present in a previously identified altered form of SAGA called SLIK, SAGA(alt), or SALSA. Analysis of an spt7 mutant with greatly reduced levels of SLIK/SAGA(alt)/SALSA suggests a subtle role for this complex in transcription that may be redundant with a subset of SAGA functions.
authors.affiliation: Department of Genetics, Harvard Medical School, 200 Longwood Avenue, Boston, MA 02115, USA.
authors.forename: Pei-Yun Jenny
authors.initials: PY
authors.lastname: Wu
authors.forename: Fred
authors.initials: F
authors.lastname: Winston
mesh_terms: D048868:Adaptor Proteins, Signal Transducing; D000878:Anthranilate Synthase / Q000096:biosynthesis / Q000235:genetics; D015152:Blotting, Northern; D015153:Blotting, Western; D004268:DNA-Binding Proteins / Q000235:genetics / Q000378:metabolism*; D005656:Fungal Proteins / Q000235:genetics / Q000378:metabolism; D005816:Genetic Complementation Test; D006836:Hydro-Lyases / Q000096:biosynthesis / Q000235:genetics; D007209:Indole-3-Glycerol-Phosphate Synthase / Q000096:biosynthesis / Q000235:genetics; D046911:Macromolecular Substances; D009097:Multienzyme Complexes / Q000096:biosynthesis / Q000235:genetics; D016297:Mutagenesis, Site-Directed; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism*; D017434:Protein Structure, Tertiary / Q000502:physiology; D012441:Saccharomyces cerevisiae / Q000235:genetics / Q000378:metabolism*; D029701:Saccharomyces cerevisiae Proteins; D015534:Trans-Activators; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism*; D015533:Transcriptional Activation / Q000502:physiology
chemical_list: D048868:Adaptor Proteins, Signal Transducing; D004268:DNA-Binding Proteins; D005656:Fungal Proteins; C106162:HFI1 protein, S cerevisiae; D046911:Macromolecular Substances; D009097:Multienzyme Complexes; D010940:Plant Proteins; C099690:SPT20 protein, S cerevisiae; C093107:SPT7 protein, S cerevisiae; D029701:Saccharomyces cerevisiae Proteins; D015534:Trans-Activators; D014157:Transcription Factors; D007209:Indole-3-Glycerol-Phosphate Synthase; D000878:Anthranilate Synthase; C087439:TRP3 protein, S cerevisiae; D006836:Hydro-Lyases; C021434:imidazoleglycerolphosphate dehydratase