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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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An MCIA-like complex is required for mitochondrial complex I assembly and seed development in maize
Gang Wang1, Yongyan Wang2, Jiacheng Ni3
1School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai 200240, China.
Molecular Plant
|August 12, 2022
Summary
Maize CRK1 (zNDUFAF1) is crucial for mitochondrial complex I assembly and seed development. This protein, along with ZmTIM17-1 and ZmIVD1, forms an MCIA-like complex essential for plant mitochondria.
Area of Science:
- Mitochondrial biology
- Plant biochemistry
- Molecular genetics
Background:
- Mitochondrial complex I biogenesis is complex, involving nuclear and mitochondrial genes.
- Plants assemble complex I differently than mammals, lacking most mammalian assembly factors.
- The evolutionary conservation of zNDUFAF1 suggests a vital role in plant complex I assembly.
Purpose of the Study:
- To investigate the function of the maize CRK1 gene in mitochondrial complex I assembly.
- To identify interacting partners of zNDUFAF1 in maize mitochondria.
- To understand the role of this assembly complex in plant development.
Main Methods:
- Map-based cloning to identify the CRK1 gene.
- Subcellular localization studies using zNDUFAF1.
- Co-immunoprecipitation assays to identify interacting proteins.
- Analysis of complex I assembly and activity in mutant lines.
- Genetic analysis of ZmTIM17-1 and ZmIVD1 knockouts.
Main Results:
- CRK1 encodes zNDUFAF1, an ortholog of human NDUFAF1, localized to mitochondria.
- Disruption of zNDUFAF1 severely impairs complex I assembly, activity, and leads to cellular bioenergetic shifts.
- zNDUFAF1 interacts with ZmTIM17-1 and ZmIVD1, forming assembly intermediates.
- Knockout of ZmTIM17-1 or ZmIVD1 also affects complex I stability and seed development.
Conclusions:
- zNDUFAF1, ZmTIM17-1, and ZmIVD1 form an MCIA-like complex essential for maize mitochondrial complex I biogenesis.
- This complex is vital for normal seed development in maize.
- Plants and mammals independently evolved mechanisms for recruiting MCIA subunits for complex I assembly.
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