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Updated: Sep 30, 2025
07:26
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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Dek504 Encodes a Mitochondrion-Targeted E+-Type Pentatricopeptide Repeat Protein Essential for RNA Editing and Seed
Zheyuan Wang1,2, Weiwei Chen1,2, Song Zhang1,2
1Beijing Innovation Center for Crop Seed Technology, Ministry of Agriculture and Rural Affairs, Key Laboratory of Crop Heterosis Utilization, Ministry of Education, College of Agronomyand Biotechnology, China Agricultural University, Beijing 100193, China.
International Journal of Molecular Sciences
|March 10, 2022
Summary
The maize gene Dek504 is crucial for RNA editing in mitochondria, ensuring proper seed development by maintaining mitochondrial complex I stability and NAD3 protein function.
Area of Science:
- Plant molecular biology
- Genetics
- Biochemistry
Background:
- RNA editing is a post-transcriptional modification in plant organelles, converting cytidine to uridine.
- Pentatricopeptide repeat (PPR) proteins are key regulators of site-specific RNA editing.
Purpose of the Study:
- To identify and characterize the maize gene responsible for the defective kernel 504 (dek504) mutation.
- To elucidate the role of Dek504 in mitochondrial RNA editing and its impact on seed development.
Main Methods:
- Map-based cloning to identify the Dek504 gene.
- Molecular characterization of the Dek504 gene and its protein product.
- Biochemical analysis of mitochondrial protein complexes and enzyme activity.
Main Results:
- The dek504 mutation causes defects in embryogenesis and endosperm development, leading to small, collapsed kernels.
- Dek504 encodes a mitochondrial PPR protein essential for editing mitochondrial NADH dehydrogenase 3 (nad3) transcripts at specific sites.
- Loss of Dek504 function reduces mitochondrial NADH dehydrogenase complex I activity due to altered NAD3 protein function.
Conclusions:
- Dek504 is vital for maize seed development by ensuring proper RNA editing of nad3, which is critical for mitochondrial function and complex I stability.
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