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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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Maize Dek51 encodes a DEAD-box RNA helicase essential for pre-rRNA processing and seed development
Le Wang1, Baoyin Chen1, Bing Ma1
1Key Laboratory of Plant Development and Environmental Adaptation Biology, Ministry of Education, School of Life Sciences, Shandong University, Qingdao 266237, China.
Cell Reports
|August 28, 2024
Summary
A maize DEAD-box RNA helicase, DEK51, is crucial for ribosome biogenesis. It processes pre-ribosomal RNA (pre-rRNA) 3' ends, and its absence halts maize seed development.
Area of Science:
- Plant molecular biology
- Ribosome biogenesis
- RNA processing
Background:
- Ribosome biosynthesis relies on precise pre-ribosomal RNA (pre-rRNA) processing.
- The mechanisms of pre-rRNA processing in plants remain incompletely understood.
- DEAD-box RNA helicases play diverse roles in RNA metabolism.
Purpose of the Study:
- To identify and characterize novel factors involved in plant pre-rRNA processing.
- To elucidate the function of a specific DEAD-box RNA helicase, DEK51, in maize (Zea mays L.).
- To investigate the role of DEK51 in the 3' end processing of 18S and 5.8S pre-rRNA.
Main Methods:
- Localization studies of DEK51 within the maize nucleolus.
- Analysis of seed development and pre-rRNA processing in DEK51 loss-of-function mutants.
- Co-immunoprecipitation assays to identify DEK51 interacting partners, including exosome components and endonucleases.
Main Results:
- DEK51 is localized in the nucleolus and is essential for maize seed development.
- Loss of DEK51 function leads to the blockage of 3' end processing for 18S and 5.8S pre-rRNA.
- DEK51 interacts with key components of the nuclear RNA exosome (ZmMTR4, ZmSMO4, ZmRRP44A, ZmRRP6L2) and endonucleases (ZmUTP24, ZmRCL1).
Conclusions:
- DEK51 is a critical DEAD-box RNA helicase that facilitates the 3' end processing of 18S and 5.8S pre-rRNA in maize.
- DEK51 likely functions by interacting with the nuclear RNA exosome complex.
- DEK51 may also be involved in the endonucleolytic cleavage steps of pre-rRNA processing, such as at site A2.
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