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Updated: Jul 19, 2026
07:46
An In Vitro Assay to Detect tRNA-Isopentenyl Transferase Activity
Published on: October 8, 2018
Diversity of tRNA genes in eukaryotes
Jeffrey M Goodenbour1, Tao Pan
1Department of Human Genetics, 929 East 57th street, Chicago, IL 60637, USA.
Nucleic Acids Research
|November 8, 2006
Summary
Eukaryotic genomes contain diverse transfer RNA (tRNA) isodecoder genes, which have the same anticodon but different sequences. This suggests a greater variety of tRNA functions than previously understood.
Area of Science:
- Genomics
- Molecular Biology
- Evolutionary Biology
Background:
- Transfer RNA (tRNA) genes are essential for protein synthesis.
- Eukaryotic genomes encode a variable number of tRNA genes and isoacceptors.
Purpose of the Study:
- To compare the diversity of chromosomal-encoded tRNA genes across 11 eukaryotic species.
- To investigate the prevalence and variation of tRNA isodecoder genes.
Main Methods:
- Genome-wide identification of tRNA genes using tRNAScan-SE.
- Analysis of tRNA gene counts, isoacceptor numbers, and isodecoder gene fractions.
- Development of a ligation-based method to detect and quantify tRNA isodecoder molecules.
Main Results:
- Significant variation in the number of tRNA isodecoder genes (10-246) was observed among eukaryotes.
- The fraction of tRNA isodecoder genes increases across the phylogenetic spectrum.
- Differential expression of three tRNA isodecoders was detected in human tissues.
Conclusions:
- The substantial number of tRNA isodecoder genes suggests a more diverse role for tRNA beyond basic translation.
- Sequence variations in human tRNA isodecoder genes are concentrated in RNA polymerase III internal promoter regions.
- Further research into tRNA isodecoder function is warranted to understand their full biological significance.
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