@article{1b66949ae4224b99acc2cda0f9eefaa9,
title = "Conformational landscape of the yeast SAGA complex as revealed by cryo-EM",
abstract = "Spt-Ada-Gcn5-Acetyltransferase (SAGA) is a conserved multi-subunit complex that activates RNA polymerase II-mediated transcription by acetylating and deubiquitinating nucleosomal histones and by recruiting TATA box binding protein (TBP) to DNA. The prototypical yeast Saccharomyces cerevisiae SAGA contains 19 subunits that are organized into Tra1, core, histone acetyltransferase, and deubiquitination modules. Recent cryo-electron microscopy studies have generated high-resolution structural information on the Tra1 and core modules of yeast SAGA. However, the two catalytical modules were poorly resolved due to conformational flexibility of the full assembly. Furthermore, the high sample requirement created a formidable barrier to further structural investigations of SAGA. Here, we report a workflow for isolating/stabilizing yeast SAGA and preparing cryo-EM specimens at low protein concentration using a graphene oxide support layer. With this procedure, we were able to determine a cryo-EM reconstruction of yeast SAGA at 3.1 {\AA} resolution and examine its conformational landscape with the neural network-based algorithm cryoDRGN. Our analysis revealed that SAGA adopts a range of conformations with its HAT module and central core in different orientations relative to Tra1.",
author = "Diana Vasyliuk and Joeseph Felt and Zhong, {Ellen D.} and Bonnie Berger and Davis, {Joseph H.} and Yip, {Calvin K.}",
note = "Funding Information: This article was funded by Natural Sciences and Engineering Research Council of Canada (RGPIN-2018-03951) and Canadian Institutes of Health Research (FDN-143228). Funding Information: This work was supported Discovery Grants from the Natural Science and Engineering Research Council of Canada (RGPIN-2018-03951 to C.K.Y.), a Foundation Grant from the Canadian Institutes of Health Research (FDN-143228 to C.K.Y), and a National Science Foundation Grant (CAREER-2046778 to J.H.D). This research project was supported in part by the UBC High Resolution Macromolecular Cryo-Electron Microscopy Facility (HRMEM). A portion of this research was supported by NIH grant U24GM129547 and performed at the PNCC at OHSU and accessed through EMSL (grid.436923.9), a DOE Office of Science User Facility sponsored by the Office of Biological and Environmental Research. We appreciate help from Theo Humphreys with data collection at PNCC. Molecular graphics and analyses performed with UCSF Chimera, developed by the Resource for Biocomputing, Visualization, and Informatics at the University of California, San Francisco, with support from NIH P41-GM103311. Funding Information: This work was supported Discovery Grants from the Natural Science and Engineering Research Council of Canada (RGPIN-2018-03951 to C.K.Y.), a Foundation Grant from the Canadian Institutes of Health Research (FDN-143228 to C.K.Y), and a National Science Foundation Grant (CAREER-2046778 to J.H.D). This research project was supported in part by the UBC High Resolution Macromolecular Cryo-Electron Microscopy Facility (HRMEM). A portion of this research was supported by NIH grant U24GM129547 and performed at the PNCC at OHSU and accessed through EMSL (grid.436923.9), a DOE Office of Science User Facility sponsored by the Office of Biological and Environmental Research. We appreciate help from Theo Humphreys with data collection at PNCC. Molecular graphics and analyses performed with UCSF Chimera, developed by the Resource for Biocomputing, Visualization, and Informatics at the University of California, San Francisco, with support from NIH P41-GM103311. Publisher Copyright: {\textcopyright} 2022, The Author(s).",
year = "2022",
month = dec,
doi = "10.1038/s41598-022-16391-0",
language = "English (US)",
volume = "12",
journal = "Scientific Reports",
issn = "2045-2322",
publisher = "Nature Publishing Group",
number = "1",
}