4W4U

Structure of yeast SAGA DUBm with Sgf73 Y57A mutant at 2.8 angstroms resolution

Summary for 4W4U

• Entry DOI: 10.2210/pdb4w4u/pdb
• Descriptor: Ubiquitin carboxyl-terminal hydrolase, Transcription and mRNA export factor SUS1, SAGA-associated factor 11, ... (6 entities in total)
• Functional Keywords: multi-protein complex, hydrolase-transcription complex, transcription-hydrolase complex, transcription/hydrolase
• Biological source: Saccharomyces cerevisiae (Baker's yeast); More
• Total number of polymer chains: 8
• Total formula weight: 175166.18

Authors

Wolberger, C.,Yan, M. (deposition date: 2014-08-15, release date: 2015-07-01, Last modification date: 2023-09-27)

Primary citation

Yan, M.,Wolberger, C.
Uncovering the role of Sgf73 in maintaining SAGA deubiquitinating module structure and activity.
J.Mol.Biol., 427:1765-1778, 2015

PubMed Abstract: The SAGA (Spt-Ada-Gcn5 acetyltransferase) complex performs multiple functions in transcription activation including deubiquitinating histone H2B, which is mediated by a subcomplex called the deubiquitinating module (DUBm). The yeast DUBm comprises a catalytic subunit, Ubp8, and three additional subunits, Sgf11, Sus1 and Sgf73, all of which are required for DUBm activity. A portion of the non-globular Sgf73 subunit lies between the Ubp8 catalytic domain and the ZnF-UBP domain and has been proposed to contribute to deubiquitinating activity by maintaining the catalytic domain in an active conformation. We report structural and solution studies of the DUBm containing two different Sgf73 point mutations that disrupt deubiquitinating activity. We find that the Sgf73 mutations abrogate deubiquitinating activity by impacting the Ubp8 ubiquitin-binding fingers region and they have an unexpected effect on the overall folding and stability of the DUBm complex. Taken together, our data suggest a role for Sgf73 in maintaining both the organization and the ubiquitin-binding conformation of Ubp8, thereby contributing to overall DUBm activity.

PubMed: 25526805
DOI: 10.1016/j.jmb.2014.12.004

Experimental method

X-RAY DIFFRACTION (2.8 Å)