Summary information and primary citation
- PDB-id
-
9hn7;
DSSR-derived features in text and
JSON formats
- Class
- RNA binding protein
- Method
- cryo-EM (2.9 Å)
- Summary
- Mouse qtrt1-2 in complex with mouse trna-tyr
- Reference
-
Guo W, Kaczmarczyk I, Kopietz K, Flegler F, Russo S,
Cigirgan E, Chramiec-Glabik A, Koziej L, Cirzi C, Peschek
J, Reuter K, Helm M, Glatt S, Tuorto F (2025): "Queuosine
is incorporated into precursor tRNA before splicing."
Nat Commun, 16, 7044. doi:
10.1038/s41467-025-62220-z.
- Abstract
- Each newly transcribed tRNA molecule must undergo
processing and receive modifications to become functional.
Queuosine (Q) is a tRNA modification present at position 34
of four tRNAs with "GUN" anticodons. Among these, the
precursor of tRNA<sub>Tyr</sub> carries an
intronic sequence within the anticodon loop that is removed
by an essential non-canonical splicing event. The
functional and temporal coupling between tRNA-splicing and
Q-incorporation remains elusive. Here, we demonstrate in
vitro and in vivo that intron-containing precursors of
tRNA<sub>Tyr</sub> are modified with Q or with
the Q-derivative galactosyl-queuosine (galQ) before being
spliced. We show that this order of events is conserved in
mouse, human, flies and worms. Using single particle
cryo-EM, we confirm that pre-tRNA<sub>Tyr</sub>
is a bona fide substrate of the QTRT1/2 complex, which
catalyzes the incorporation of Q into the tRNA. Our results
elucidate the hierarchical interplay that coordinates
Q-incorporation and splicing in eukaryotic tRNAs, providing
a relevant but unappreciated aspect of the cellular tRNA
maturation process.
