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Discrimintion and Mapping of the Primary and Processed Transcripts in Maize Mitochondrion Using a Circular RT-PCR-based Strategy
Published on: July 29, 2019
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SUV3 helicase is required for correct processing of mitochondrial transcripts
Paula Clemente1, Aleksandra Pajak1, Isabelle Laine1
1Division of Metabolic Diseases, Department of Laboratory Medicine; Karolinska Institutet, Stockholm 17177, Sweden.
Nucleic Acids Research
|July 9, 2015
Summary
The mitochondrial helicase SUV3 is crucial for processing mitochondrial transcripts in fruit flies. Its disruption causes RNA processing defects, impacting translation and leading to lethality.
Area of Science:
- Mitochondrial biology
- Molecular genetics
- Post-transcriptional regulation
Background:
- Mitochondrial gene expression relies on post-transcriptional control of mRNA.
- The mitochondrial degradosome, including helicase SUV3 and PNPase, is implicated in mRNA turnover.
- The precise in vivo function of SUV3 in metazoans remains unclear.
Purpose of the Study:
- To investigate the in vivo function of the mitochondrial helicase SUV3 in Drosophila melanogaster.
- To elucidate the role of SUV3 in mitochondrial RNA processing and gene expression.
Main Methods:
- Disruption of the Drosophila melanogaster SUV3 homolog (dmsuv3).
- Analysis of mitochondrial mRNA and tRNA levels.
- Assessment of mitochondrial translation and respiratory chain complex activity.
Main Results:
- Loss of dmsuv3 resulted in mitochondrial mRNA accumulation without increased transcription or decay intermediates.
- Mitochondrial tRNA levels significantly decreased, with accumulation of unprocessed precursor transcripts.
- Defective RNA processing led to reduced mitochondrial translation and respiratory chain deficiency.
- dmsuv3 mutants exhibited a pupal lethal phenotype.
Conclusions:
- SUV3 is essential for processing polycistronic mitochondrial transcripts in metazoans.
- This processing function of SUV3 is independent of PNPase.
- SUV3 plays a critical role in maintaining mitochondrial function and organismal viability.
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