title: Crystal structure of the eukaryotic 40S ribosomal subunit in complex with initiation factor 1.
abstract: Eukaryotic ribosomes are substantially larger and more complex than their bacterial counterparts. Although their core function is conserved, bacterial and eukaryotic protein synthesis differ considerably at the level of initiation. The eukaryotic small ribosomal subunit (40S) plays a central role in this process; it binds initiation factors that facilitate scanning of messenger RNAs and initiation of protein synthesis. We have determined the crystal structure of the Tetrahymena thermophila 40S ribosomal subunit in complex with eukaryotic initiation factor 1 (eIF1) at a resolution of 3.9 angstroms. The structure reveals the fold of the entire 18S ribosomal RNA and of all ribosomal proteins of the 40S subunit, and defines the interactions with eIF1. It provides insights into the eukaryotic-specific aspects of protein synthesis, including the function of eIF1 as well as signaling and regulation mediated by the ribosomal proteins RACK1 and rpS6e.
authors.affiliation: Institute of Molecular Biology and Biophysics, ETH Zürich, Schafmattstrasse 20, 8093 Zürich, Switzerland.
authors.forename: Julius
authors.initials: J
authors.lastname: Rabl
authors.forename: Marc
authors.initials: M
authors.lastname: Leibundgut
authors.forename: Sandro F
authors.initials: SF
authors.lastname: Ataide
authors.forename: Andrea
authors.initials: A
authors.lastname: Haag
authors.forename: Nenad
authors.initials: N
authors.lastname: Ban
mesh_terms: D000595:Amino Acid Sequence; D003460:Crystallization; D018360:Crystallography, X-Ray; D015977:Eukaryotic Initiation Factor-1 / Q000737:chemistry* / Q000378:metabolism; D008958:Models, Molecular; D008969:Molecular Sequence Data; D009690:Nucleic Acid Conformation; D014176:Protein Biosynthesis; D011487:Protein Conformation; D017510:Protein Folding; D015800:Protozoan Proteins / Q000737:chemistry / Q000378:metabolism; D012333:RNA, Messenger / Q000737:chemistry; D016053:RNA, Protozoan / Q000737:chemistry; D012337:RNA, Ribosomal, 18S / Q000737:chemistry*; D012269:Ribosomal Proteins / Q000737:chemistry* / Q000378:metabolism; D054682:Ribosome Subunits, Small, Eukaryotic / Q000737:chemistry* / Q000378:metabolism / Q000648:ultrastructure*; D015398:Signal Transduction; D016808:Tetrahymena thermophila / Q000737:chemistry* / Q000648:ultrastructure*
chemical_list: D015977:Eukaryotic Initiation Factor-1; D015800:Protozoan Proteins; D012333:RNA, Messenger; D016053:RNA, Protozoan; D012337:RNA, Ribosomal, 18S; D012269:Ribosomal Proteins