Concurrent remodelling of nucleolar 60S subunit precursors by the Rea1 ATPase and Spb4 RNA helicase
Biogenesis intermediates of nucleolar ribosomal 60S precursor particles undergo a number of structural maturation steps before they transit to the nucleoplasm and are finally exported into the cytoplasm. The AAA+-ATPase Rea1 participates in the nucleolar exit by releasing the Ytm1–Erb1 heterodimer f...
Saved in:
| Main Authors: | , , , , , |
|---|---|
| Format: | Article (Journal) |
| Language: | English |
| Published: |
17 March 2023
|
| In: |
eLife
Year: 2023, Volume: 12, Pages: 1-22 |
| ISSN: | 2050-084X |
| DOI: | 10.7554/eLife.84877 |
| Online Access: | Verlag, lizenzpflichtig, Volltext: https://doi.org/10.7554/eLife.84877
|
| Author Notes: | Valentin Mitterer, Matthias Thoms, Robert Buschauer, Otto Berninghausen, Ed Hurt, Roland Beckmann |
| Summary: | Biogenesis intermediates of nucleolar ribosomal 60S precursor particles undergo a number of structural maturation steps before they transit to the nucleoplasm and are finally exported into the cytoplasm. The AAA+-ATPase Rea1 participates in the nucleolar exit by releasing the Ytm1–Erb1 heterodimer from the evolving pre-60S particle. Here, we show that the DEAD-box RNA helicase Spb4 with its interacting partner Rrp17 is further integrated into this maturation event. Spb4 binds to a specific class of late nucleolar pre-60S intermediates, whose cryo-EM structure revealed how its helicase activity facilitates melting and restructuring of 25S rRNA helices H62 and H63/H63a prior to Ytm1–Erb1 release. In vitro maturation of such Spb4-enriched pre-60S particles, incubated with purified Rea1 and its associated pentameric Rix1-complex in the presence of ATP, combined with cryo-EM analysis depicted the details of the Rea1-dependent large-scale pre-ribosomal remodeling. Our structural insights unveil how the Rea1 ATPase and Spb4 helicase remodel late nucleolar pre-60S particles by rRNA restructuring and dismantling of a network of several ribosomal assembly factors. |
|---|---|
| Item Description: | Gesehen am 12.06.2023 |
| Physical Description: | Online Resource |
| ISSN: | 2050-084X |
| DOI: | 10.7554/eLife.84877 |