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Updated: Jul 15, 2025
09:19
RNA Catalyst as a Reporter for Screening Drugs against RNA Editing in Trypanosomes
Published on: July 22, 2014
8.5K
RNA editing catalytic complexes edit multiple mRNA sites non-processively in Trypanosoma brucei
Jason Carnes1, Suzanne M McDermott2, Kenneth Stuart2
1Seattle Children's Research Institute, Seattle, WA 98109, USA.
Molecular and Biochemical Parasitology
|September 24, 2023
Summary
RNA editing in T. brucei involves multiple complexes (RECCs) with specific endonucleases. These complexes work non-processively, engaging and disengaging sequentially to edit mitochondrial mRNAs with both insertions and deletions.
Area of Science:
- Molecular Biology
- RNA Biology
- Parasitology
Background:
- Mitochondrial mRNA editing in Trypanosoma brucei involves uridine insertion/deletion.
- Guide RNAs (gRNAs) specify editing sites (ESs).
- Three RNA Editing Catalytic Complexes (RECCs) perform editing, each with distinct endonucleases.
Purpose of the Study:
- Investigate the dynamic nature of RECC endonuclease composition during editing.
- Determine how RECCs handle combined insertion and deletion editing sites specified by single gRNAs.
- Clarify the mechanism of editing complex interactions at consecutive editing sites.
Main Methods:
- In vivo BirA* proximity labeling to assess protein associations.
- Analysis of RECC protein stoichiometry under varying expression levels.
- Investigated effects of endonuclease overexpression on RECCs and cell growth.
Main Results:
- Endonucleases remain stably associated with common RECC proteins at physiological levels.
- Overexpression of endonuclease components had minor effects and did not impact growth.
- RECC protein stoichiometries can be altered by expression perturbations.
Conclusions:
- Editing of consecutive insertion and deletion ESs is non-processive, involving successive RECC engagement/disengagement.
- This clarifies the mechanism behind complex, partially edited mRNA patterns in vivo.
- RECCs function independently and sequentially rather than as a single processive unit.
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