Concurrent remodelling of nucleolar 60S subunit precursors by the Rea1 ATPase and Spb4 RNA helicase

• Verfasst von: Mitterer, Valentin [VerfasserIn]
• Verfasst von: Thoms, Matthias [VerfasserIn]
• Verfasst von: Buschauer, Thomas [VerfasserIn]
• Verfasst von: Berninghausen, Otto [VerfasserIn]
• Verfasst von: Hurt, Ed [VerfasserIn]
• Verfasst von: Beckmann, Roland [VerfasserIn]
• Titel: Concurrent remodelling of nucleolar 60S subunit precursors by the Rea1 ATPase and Spb4 RNA helicase
• Verf.angabe: Valentin Mitterer, Matthias Thoms, Robert Buschauer, Otto Berninghausen, Ed Hurt, Roland Beckmann
• E-Jahr: 2023
• Jahr: 17 March 2023
• Umfang: 22 S.
• Fussnoten: Gesehen am 12.06.2023
• Titel Quelle: Enthalten in: eLife
• Ort Quelle: Cambridge : eLife Sciences Publications, 2012
• Jahr Quelle: 2023
• Band/Heft Quelle: 12(2023) vom: März, Artikel-ID e84877, Seite 1-22
• ISSN Quelle: 2050-084X
• DOI: doi:10.7554/eLife.84877
• Datenträger: Online-Ressource
• Sprache: eng
• K10plus-PPN: 1848748515

Abstract

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.