Database of articles cited by EMDB/PDB/SASBDB data

Keywords
Structure methods	All X-ray diffraction NMR electron microscopy small angle scattering neutron diffraction fiber diffraction powder diffraction infrared spectroscopy EPR fluorescence transfer theoretical model Hybrid
Author
Journal
IF	>30 >20 >10 >5 all

Title	Structural basis for the final steps of human 40S ribosome maturation.
Journal, issue, pages	Nature, Vol. 587, Issue 7835, Page 683-687, Year 2020
Publish date	Nov 18, 2020
Authors	Michael Ameismeier / Ivo Zemp / Jasmin van den Heuvel / Matthias Thoms / Otto Berninghausen / Ulrike Kutay / Roland Beckmann /
PubMed Abstract	Eukaryotic ribosomes consist of a small 40S and a large 60S subunit that are assembled in a highly coordinated manner. More than 200 factors ensure correct modification, processing and folding of ...Eukaryotic ribosomes consist of a small 40S and a large 60S subunit that are assembled in a highly coordinated manner. More than 200 factors ensure correct modification, processing and folding of ribosomal RNA and the timely incorporation of ribosomal proteins. Small subunit maturation ends in the cytosol, when the final rRNA precursor, 18S-E, is cleaved at site 3 by the endonuclease NOB1. Previous structures of human 40S precursors have shown that NOB1 is kept in an inactive state by its partner PNO1. The final maturation events, including the activation of NOB1 for the decisive rRNA-cleavage step and the mechanisms driving the dissociation of the last biogenesis factors have, however, remained unresolved. Here we report five cryo-electron microscopy structures of human 40S subunit precursors, which describe the compositional and conformational progression during the final steps of 40S assembly. Our structures explain the central role of RIOK1 in the displacement and dissociation of PNO1, which in turn allows conformational changes and activation of the endonuclease NOB1. In addition, we observe two factors, eukaryotic translation initiation factor 1A domain-containing protein (EIF1AD) and leucine-rich repeat-containing protein 47 (LRRC47), which bind to late pre-40S particles near RIOK1 and the central rRNA helix 44. Finally, functional data shows that EIF1AD is required for efficient assembly factor recycling and 18S-E processing. Our results thus enable a detailed understanding of the last steps in 40S formation in human cells and, in addition, provide evidence for principal differences in small ribosomal subunit formation between humans and the model organism Saccharomyces cerevisiae.
External links	Nature / PubMed:33208940
Methods	EM (single particle)
Resolution	2.6 - 3.7 Å
Structure data	11517 6zxd EMDB-11517, PDB-6zxd: Cryo-EM structure of a late human pre-40S ribosomal subunit - State F1 Method: EM (single particle) / Resolution: 3.2 Å 11518 6zxe EMDB-11518, PDB-6zxe: Cryo-EM structure of a late human pre-40S ribosomal subunit - State F2 Method: EM (single particle) / Resolution: 3.0 Å 11519 6zxf EMDB-11519, PDB-6zxf: Cryo-EM structure of a late human pre-40S ribosomal subunit - State G Method: EM (single particle) / Resolution: 3.7 Å 11520 6zxg EMDB-11520, PDB-6zxg: Cryo-EM structure of a late human pre-40S ribosomal subunit - State H1 Method: EM (single particle) / Resolution: 2.6 Å 11521 6zxh EMDB-11521, PDB-6zxh: Cryo-EM structure of a late human pre-40S ribosomal subunit - State H2 Method: EM (single particle) / Resolution: 2.7 Å
Chemicals	ChemComp-ZN: Unknown entry ChemComp-MG: Unknown entry ChemComp-ATP: ADENOSINE-5'-TRIPHOSPHATE / ATP, energy-carrying moleculeYM ChemComp-ASP*: ASPARTIC ACID
Source	homo sapiens (human)
Keywords	RIBOSOME / Ribosome Biogenesis / Pre-40S