Download MendeleyIn vitro structural maturation of an early stage pre-40S particle coupled with U3 snoRNA release and central pseudoknot formation.
Cheng, J., La Venuta, G., Lau, B., Berninghausen, O., Beckmann, R., Hurt, E.(2022) Nucleic Acids Res 50: 11916-11923
- PubMed: 36263816
- DOI: https://doi.org/10.1093/nar/gkac910
- Primary Citation of Related Structures:
7WTL, 7WTM - PubMed Abstract:
The transition of the 90S to the pre-40S pre-ribosome is a decisive step in eukaryotic small subunit biogenesis leading to a first pre-40S intermediate (state Dis-C or primordial pre-40S), where the U3 snoRNA keeps the nascent 18S rRNA locally immature. We in vitro reconstitute the ATP-dependent U3 release from this particle, catalyzed by the helicase Dhr1, and follow this process by cryo-EM revealing two successive pre-40S intermediates, Dis-D and Dis-E. The latter has lost not only U3 but all residual 90S factors including the GTPase Bms1. In vitro remodeling likewise induced the formation of the central pseudoknot, a universally conserved tertiary RNA structure that comprises the core of the small subunit decoding center. Thus, we could structurally reveal a key tertiary RNA folding step that is essential to form the active 40S subunit.
Organizational Affiliation:
Gene Center and Department of Biochemistry, University of Munich LMU, Feodor-Lynen-Str. 25, 81377 Munich, Germany.
