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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
PPR336 is associated with polysomes in plant mitochondria
Magalie Uyttewaal1, Hakim Mireau, Michal Rurek
1Station de Génétique et d'Amélioration des Plantes, INRA, Route de Saint-Cyr, 78026 Versailles Cedex, France.
Journal of Molecular Biology
|December 7, 2007
Summary
Pentatricopeptide repeat (PPR) protein PPR336 is a mitochondrial protein associated with ribosomes. Mutants show altered mitochondrial polysomes, suggesting PPR336
Area of Science:
- Plant Molecular Biology
- Mitochondrial Gene Expression
- Organelle Genetics
Background:
- Pentatricopeptide repeat (PPR) proteins regulate organelle gene expression post-transcriptionally.
- Plant mitochondrial translation is poorly understood, representing a key knowledge gap.
- PPR proteins are crucial for various steps in organelle gene expression.
Purpose of the Study:
- To investigate the function of the pentatricopeptide repeat protein PPR336 in Arabidopsis mitochondria.
- To elucidate the role of PPR336 in mitochondrial gene expression, particularly translation.
- To characterize the molecular interactions and localization of PPR336 within the mitochondrion.
Main Methods:
- Identification of PPR336 within high-molecular-weight complexes in Arabidopsis mitochondria.
- Biochemical analysis of PPR336 localization and association with mitochondrial membranes and ribosomes.
- Analysis of mitochondrial polysome profiles in wild-type and Ppr336/336-like mutants using sucrose gradients and polysome destabilization.
Main Results:
- PPR336 is a short, highly expressed mitochondrial protein, unusual for the PPR family.
- PPR336 is associated with the inner mitochondrial membrane and forms an RNase-sensitive complex.
- PPR336 localizes to ribosomes, and its absence leads to accumulation of lower molecular weight mitochondrial polysomes.
Conclusions:
- PPR336 is a mitochondrial protein involved in ribosome association.
- The data strongly suggest PPR336 plays a role in plant mitochondrial translation.
- PPR336 represents a novel factor in the regulation of mitochondrial gene expression.
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