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Updated: May 5, 2026

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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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tRNA 3' processing in yeast involves tRNase Z, Rex1, and Rrp6.
Summary
The yeast tRNA 3' endonuclease Trz1 (tRNase Z) is confirmed to process tRNA 3' ends via an endonucleolytic pathway. This pathway is preferred for most tRNAs and essential for those with long 3' trailers, also functioning in mitochondria.
Area of Science:
- Molecular Biology
- Yeast Genetics
- RNA Metabolism
Background:
- Mature tRNA 3' ends in Saccharomyces cerevisiae are generated by endonucleolytic and exonucleolytic pathways.
- Exonucleolytic trimming is attributed to Rex1 and Rrp6, but the endonuclease remained unconfirmed in vivo.
Purpose of the Study:
- To identify and confirm the endonuclease responsible for endonucleolytic tRNA 3' processing in yeast.
- To elucidate the role of Trz1 (tRNase Z) in tRNA 3' end maturation.
Main Methods:
- In vivo studies in Saccharomyces cerevisiae.
- Analysis of tRNA 3' end processing pathways.
- Investigating the function of Trz1 in both nuclear and mitochondrial compartments.
Main Results:
- The yeast tRNA 3' endonuclease, Trz1 (tRNase Z), was confirmed to catalyze endonucleolytic tRNA 3' processing.
- Most tRNAs utilize both endonucleolytic and exonucleolytic pathways, with a preference for the endonucleolytic route.
- Trz1's role is more critical for precursors with long 3' trailers and extends to mitochondrial tRNA processing.
Conclusions:
- Trz1 is the primary endonuclease for tRNA 3' end processing in yeast.
- The endonucleolytic pathway, mediated by Trz1, is a major route for tRNA maturation.
- Trz1 plays a significant role in both nuclear and mitochondrial RNA metabolism.
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