Mapping the deubiquitination module within the SAGA complex

Structure. 2014 Nov 4;22(11):1553-9. doi: 10.1016/j.str.2014.07.017.


The molecular organization of the yeast transcriptional coactivator Spt-Ada-Gcn5 acetyltransferase (SAGA) was analyzed by single-particle electron microscopy. Complete or partial deletion of the Sgf73 subunit disconnects the deubiquitination (DUB) module from SAGA and favors in our conditions the cleavage of the C-terminal ends of the Spt7 subunit and the loss of the Spt8 subunit. The structural comparison of the wild-type SAGA with two deletion mutants positioned the DUB module and enabled the fitting of the available atomic models. The localization of the DUB module close to Gcn5 defines a chromatin-binding interface within SAGA, which could be demonstrated by the binding of nucleosome core particles. The TATA-box binding protein (TBP)-interacting subunit Spt8 was found to be located close to the DUB but in a different domain than Spt3, also known to contact TBP. A flexible protein arm brings both subunits close enough to interact simultaneously with TBP.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Binding Sites
  • Chromatin / metabolism
  • Histone Acetyltransferases / genetics*
  • Microscopy, Electron / methods*
  • Models, Molecular
  • Protein Interaction Domains and Motifs
  • Protein Multimerization
  • Saccharomyces cerevisiae / genetics
  • Saccharomyces cerevisiae / metabolism*
  • Saccharomyces cerevisiae Proteins / chemistry*
  • Saccharomyces cerevisiae Proteins / genetics
  • Saccharomyces cerevisiae Proteins / metabolism
  • Sequence Deletion
  • Trans-Activators / chemistry*
  • Trans-Activators / genetics
  • Trans-Activators / metabolism
  • Transcription Factors / chemistry*
  • Ubiquitination


  • Chromatin
  • SAGA complex, S cerevisiae
  • SPT7 protein, S cerevisiae
  • SPT8 protein, S cerevisiae
  • Saccharomyces cerevisiae Proteins
  • Trans-Activators
  • Transcription Factors
  • GCN5 protein, S cerevisiae
  • Histone Acetyltransferases
  • Sgf73 protein, S cerevisiae