Thermophile 90S Pre-ribosome Structures Reveal the Reverse Order of Co-transcriptional 18S rRNA Subdomain Integration.
90S pre-ribosome
Chaetomium thermophilum
NAT10 acetyltransferase
RNA folding
Saccharomyces cerevisiae
biochemical reconstitution
cryo-EM
rRNA
ribosome assembly
yeast genetics
Journal
Molecular cell
ISSN: 1097-4164
Titre abrégé: Mol Cell
Pays: United States
ID NLM: 9802571
Informations de publication
Date de publication:
19 09 2019
19 09 2019
Historique:
received:
19
04
2019
revised:
11
06
2019
accepted:
21
06
2019
pubmed:
6
8
2019
medline:
30
1
2020
entrez:
6
8
2019
Statut:
ppublish
Résumé
Eukaryotic ribosome biogenesis involves RNA folding and processing that depend on assembly factors and small nucleolar RNAs (snoRNAs). The 90S (SSU-processome) is the earliest pre-ribosome structurally analyzed, which was suggested to assemble stepwise along the growing pre-rRNA from 5' > 3', but this directionality may not be accurate. Here, by analyzing the structure of a series of 90S assembly intermediates from Chaetomium thermophilum, we discover a reverse order of 18S rRNA subdomain incorporation. Large parts of the 18S rRNA 3' and central domains assemble first into the 90S before the 5' domain is integrated. This final incorporation depends on a contact between a heterotrimer Enp2-Bfr2-Lcp5 recruited to the flexible 5' domain and Kre33, which reconstitutes the Kre33-Enp-Brf2-Lcp5 module on the compacted 90S. Keeping the 5' domain temporarily segregated from the 90S scaffold could provide extra time to complete the multifaceted 5' domain folding, which depends on a distinct set of snoRNAs and processing factors.
Identifiants
pubmed: 31378463
pii: S1097-2765(19)30489-7
doi: 10.1016/j.molcel.2019.06.032
pii:
doi:
Substances chimiques
Fungal Proteins
0
RNA, Fungal
0
RNA, Ribosomal, 18S
0
Types de publication
Journal Article
Research Support, Non-U.S. Gov't
Langues
eng
Sous-ensembles de citation
IM
Pagination
1256-1269.e7Informations de copyright
Copyright © 2019 Elsevier Inc. All rights reserved.