8I9R

Cryo-EM structure of a Chaetomium thermophilum pre-60S ribosomal subunit - State 5S RNP

This is a non-PDB format compatible entry.

Summary for 8I9R

• Entry DOI: 10.2210/pdb8i9r/pdb
• EMDB information: 35281
• Descriptor: RNA (3341-MER), 60S ribosomal protein l7-like protein, Eukaryotic translation initiation factor 6, ... (49 entities in total)
• Functional Keywords: ribosome, ribosome biogenesis, pre-60s ribosome
• Biological source: Chaetomium thermophilum; More
• Total number of polymer chains: 49
• Total formula weight: 2865780.81

Authors

Lau, B.,Huang, Z.,Beckmann, R.,Hurt, E.,Cheng, J. (deposition date: 2023-02-07, release date: 2023-05-17, Last modification date: 2023-07-19)

Primary citation

Lau, B.,Huang, Z.,Kellner, N.,Niu, S.,Berninghausen, O.,Beckmann, R.,Hurt, E.,Cheng, J.
Mechanism of 5S RNP recruitment and helicase-surveilled rRNA maturation during pre-60S biogenesis.
Embo Rep., 24:e56910-e56910, 2023

PubMed Abstract: Ribosome biogenesis proceeds along a multifaceted pathway from the nucleolus to the cytoplasm that is extensively coupled to several quality control mechanisms. However, the mode by which 5S ribosomal RNA is incorporated into the developing pre-60S ribosome, which in humans links ribosome biogenesis to cell proliferation by surveillance by factors such as p53-MDM2, is poorly understood. Here, we report nine nucleolar pre-60S cryo-EM structures from Chaetomium thermophilum, one of which clarifies the mechanism of 5S RNP incorporation into the early pre-60S. Successive assembly states then represent how helicases Dbp10 and Spb4, and the Pumilio domain factor Puf6 act in series to surveil the gradual folding of the nearby 25S rRNA domain IV. Finally, the methyltransferase Spb1 methylates a universally conserved guanine nucleotide in the A-loop of the peptidyl transferase center, thereby licensing further maturation. Our findings provide insight into the hierarchical action of helicases in safeguarding rRNA tertiary structure folding and coupling to surveillance mechanisms that culminate in local RNA modification.

PubMed: 37129998
DOI: 10.15252/embr.202356910

Experimental method

ELECTRON MICROSCOPY (3.1 Å)