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Global Identification of Co-Translational Interaction Networks by Selective Ribosome Profiling
Published on: October 7, 2021
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Visualizing maturation factor extraction from the nascent ribosome by the AAA-ATPase Drg1
Michael Prattes1,2, Irina Grishkovskaya3, Victor-Valentin Hodirnau4
1Institute of Molecular Biosciences, University of Graz, Graz, Austria.
Nature Structural & Molecular Biology
|September 13, 2022
Summary
The AAA-ATPase Drg1 extracts Rlp24 from ribosomal subunits, a crucial step in ribosome biogenesis. Cryo-EM structures reveal how Arx1 and rRNA expansion segment ES27 facilitate this Rlp24 release mechanism.
Area of Science:
- Molecular Biology
- Cell Biology
- Structural Biology
Background:
- Drg1, an AAA-ATPase, is essential for eukaryotic ribosome biogenesis.
- Drg1 initiates cytoplasmic maturation of the large ribosomal subunit by releasing Rlp24.
- The mechanism of Rlp24 release by Drg1 was previously unknown.
Purpose of the Study:
- To elucidate the molecular mechanism by which Drg1 extracts Rlp24 from pre-60S particles.
- To provide a step-by-step understanding of Drg1 substrate recognition and processing.
Main Methods:
- Cryo-electron microscopy (cryo-EM) structure determination.
- Biochemical analysis of Drg1-mediated Rlp24 extraction.
Main Results:
- Cryo-EM structures captured Drg1 extracting Rlp24 from pre-60S particles.
- Arx1 and rRNA expansion segment ES27 form a docking platform for Drg1.
- Drg1 utilizes a hand-over-hand translocation mechanism to extract Rlp24.
Conclusions:
- The study reveals the detailed mechanism of Rlp24 extraction by Drg1.
- Identifies Arx1 and ES27 as key components positioning Drg1 for substrate release.
- Provides mechanistic insights into the conserved function of AAA-ATPases.
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