# tRNA editing by deamination: Balancing affinity and specificity

> **NIH NIH R01** · OHIO STATE UNIVERSITY · 2021 · $360,007

## Abstract

In all organisms, tRNAs are matured by a series of post-transcriptional processing
events before they can partake in protein synthesis. These include end trimming to
generate the correct 5' and 3' ends, and a substantial number of post-transcriptional
chemical modifications; these ensure proper structure and function. Despite much effort
many modifications have not been recapitulated in vitro, which have made
understanding their mechanism difficult, if not impossible. One such event entails the C
to U editing of tRNAs at the anticodon, a discovery that dates back to almost 25 years,
but one for which no in vitro assay was available. Recently, we established the first in
vitro assay for C to U editing in any system. Our studies also revealed that before editing
can take place, the edited position must also be methylated and both enzymes, the
deaminase and the methylase, strictly require each other for activity. This allowed us to
introduce a new concept of “enzyme co-activation”, one that may guide biochemical
studies of other modifications for which no in vitro assay currently exist. Additionally,
given that tRNA editing and modification in T. brucei is peppered with unique features,
successful completion of these studies will generate important basic information on the
mechanism and evolution of tRNA editing and modification, reveal unique features
specific to T. brucei but which undoubtedly impact other systems.
!

## Key facts

- **NIH application ID:** 10173794
- **Project number:** 5R01GM084065-12
- **Recipient organization:** OHIO STATE UNIVERSITY
- **Principal Investigator:** Juan D Alfonzo
- **Activity code:** R01 (R01, R21, SBIR, etc.)
- **Funding institute:** NIH
- **Fiscal year:** 2021
- **Award amount:** $360,007
- **Award type:** 5
- **Project period:** 2008-08-01 → 2023-11-30

## Primary source

NIH RePORTER: https://reporter.nih.gov/project-details/10173794

## Citation

> US National Institutes of Health, RePORTER application 10173794, tRNA editing by deamination: Balancing affinity and specificity (5R01GM084065-12). Retrieved via AI Analytics 2026-05-24 from https://api.ai-analytics.org/grant/nih/10173794. Licensed CC0.

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