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tRNA dynamics between the nucleus, cytoplasm and mitochondrial surface: Location, location, location
Kunal Chatterjee1, Regina T Nostramo2, Yao Wan1
1The Ohio State University Comprehensive Cancer Research Center, United States; Department of Molecular Genetics, The Ohio State University, United States; Center for RNA Biology, The Ohio State University, United States.
Biochimica Et Biophysica Acta. Gene Regulatory Mechanisms
|December 2, 2017
Summary
Transfer RNAs (tRNAs) move bidirectionally between the nucleus and cytoplasm through three key steps: primary export, retrograde import, and re-export. This complex trafficking influences gene expression and is exploited by viruses.
Area of Science:
- Molecular Biology
- Cell Biology
- Genetics
Background:
- Transfer RNAs (tRNAs) are crucial for protein translation in the cytoplasm.
- tRNA transcription and processing predominantly occur in the nucleus, necessitating nuclear export.
- Bidirectional tRNA transport between nucleus and cytoplasm is essential for cellular function.
Purpose of the Study:
- To elucidate the three distinct steps of tRNA nuclear-cytoplasmic transport.
- To describe the regulation of tRNA trafficking pathways.
- To explore the role of tRNA export in cellular proteome regulation and mitochondrial pre-tRNA splicing.
Main Methods:
- Review and synthesis of existing literature on tRNA nuclear transport.
- Analysis of conserved mechanisms in yeast and vertebrate cells.
- Examination of viral hijacking of tRNA transport pathways (e.g., HIV).
Main Results:
- Identified and described three steps: primary tRNA nuclear export, retrograde nuclear import, and nuclear re-export.
- Highlighted substrate specificity among tRNA nuclear exporters, suggesting proteome regulation.
- Described mitochondrial localization of the pre-tRNA splicing endonuclease (SEN) complex and its function.
Conclusions:
- tRNA nuclear-cytoplasmic shuttling is a complex, regulated, and conserved process.
- tRNA export pathways may regulate the cellular proteome.
- Mitochondrial pre-tRNA splicing represents an additional layer of tRNA biogenesis regulation.
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