Cryo-EM structure of the fully assembled Elongator complex.
Marcin Jaciuk1, David Scherf2, Karol Kaszuba3,4
1Malopolska Centre of Biotechnology (MCB), Jagiellonian University, Krakow 30-387, Poland.
Nucleic Acids Research
|January 8, 2023
Summary
Researchers reveal the structure of the Elongator complex, crucial for tRNA modification and protein synthesis. This finding clarifies how Elongator ensures proteome integrity by understanding its assembly and function.
Area of Science:
- Molecular Biology
- Structural Biology
- Biochemistry
Background:
- Transfer RNA (tRNA) modifications are vital for accurate protein synthesis.
- Elongator complex modifies wobble uridines in eukaryotic tRNAs.
- The structure and function of the Elp456 subcomplex were previously unknown.
Purpose of the Study:
- Determine the structure of the yeast Elongator complex using cryo-electron microscopy.
- Investigate the structural conservation of Elongator across eukaryotes.
- Elucidate the molecular basis of Elongator assembly and tRNA modification activity.
Main Methods:
- Cryo-electron microscopy (cryo-EM) for structural determination.
- Mutational analyses (in vitro and in vivo) for validation.
- Biochemical characterization of human Elongator.
Main Results:
- Resolved the cryo-EM structure of yeast Elongator (4.3 Å) and mouse Elongator (5.9 Å).
- Confirmed structural conservation of Elongator and its intermediates across species.
- Provided biochemical characterization of the assembled human Elongator.
Conclusions:
- The study provides the first high-resolution structures of the Elongator complex.
- Structural conservation highlights Elongator's fundamental role in eukaryotes.
- Molecular insights into Elongator assembly and function pave the way for understanding tRNA modification.
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