title: Architecture of the yeast small subunit processome.
abstract: The small subunit (SSU) processome, a large ribonucleoprotein particle, organizes the assembly of the eukaryotic small ribosomal subunit by coordinating the folding, cleavage, and modification of nascent pre-ribosomal RNA (rRNA). Here, we present the cryo-electron microscopy structure of the yeast SSU processome at 5.1-angstrom resolution. The structure reveals how large ribosome biogenesis complexes assist the 5' external transcribed spacer and U3 small nucleolar RNA in providing an intertwined RNA-protein assembly platform for the separate maturation of 18S rRNA domains. The strategic placement of a molecular motor at the center of the particle further suggests a mechanism for mediating conformational changes within this giant particle. This study provides a structural framework for a mechanistic understanding of eukaryotic ribosome assembly in the model organism Saccharomyces cerevisiae.
authors.affiliation: Laboratory of Protein and Nucleic Acid Chemistry, The Rockefeller University, New York, NY 10065, USA.|Tri-Institutional Training Program in Chemical Biology, The Rockefeller University, New York, NY 10065, USA.
authors.forename: Malik
authors.initials: M
authors.lastname: Chaker-Margot
authors.affiliation: Laboratory of Protein and Nucleic Acid Chemistry, The Rockefeller University, New York, NY 10065, USA.
authors.forename: Jonas
authors.initials: J
authors.lastname: Barandun
authors.affiliation: Laboratory of Protein and Nucleic Acid Chemistry, The Rockefeller University, New York, NY 10065, USA.
authors.forename: Mirjam
authors.initials: M
authors.lastname: Hunziker
authors.affiliation: Laboratory of Protein and Nucleic Acid Chemistry, The Rockefeller University, New York, NY 10065, USA. klinge@rockefeller.edu.
authors.forename: Sebastian
authors.initials: S
authors.lastname: Klinge
mesh_terms: D020285:Cryoelectron Microscopy; D009690:Nucleic Acid Conformation; D000072757:Protein Conformation, beta-Strand; D012331:RNA, Fungal / Q000737:chemistry / Q000648:ultrastructure; D012335:RNA, Ribosomal / Q000737:chemistry / Q000648:ultrastructure; D012337:RNA, Ribosomal, 18S / Q000737:chemistry / Q000648:ultrastructure; D020537:RNA, Small Nucleolar / Q000737:chemistry / Q000648:ultrastructure; D054682:Ribosome Subunits, Small, Eukaryotic / Q000737:chemistry* / Q000648:ultrastructure*; D012441:Saccharomyces cerevisiae / Q000737:chemistry* / Q000648:ultrastructure*; D029701:Saccharomyces cerevisiae Proteins / Q000737:chemistry / Q000648:ultrastructure
chemical_list: D012331:RNA, Fungal; D012335:RNA, Ribosomal; D012337:RNA, Ribosomal, 18S; D020537:RNA, Small Nucleolar; C117378:RNA, U3 small nucleolar; D029701:Saccharomyces cerevisiae Proteins