A Cytidine Deaminase Edits C to U in Transfer RNAs in Archaea
Lennart Randau,1,*,
Bradford J. Stanley,1,*
Andrew Kohlway,1
Sarah Mechta,1
Yong Xiong,1,
Dieter Söll1,2,
All canonical transfer RNAs (tRNAs) have a uridine at position
8, involved in maintaining tRNA tertiary structure. However,
the hyperthermophilic archaeon
Methanopyrus kandleri harbors
30 (out of 34) tRNA genes with cytidine at position 8. Here,
we demonstrate C-to-U editing at this location in the tRNA’s
tertiary core, and present the crystal structure of a tRNA-specific
cytidine deaminase, CDAT8, which has the cytidine deaminase
domain linked to a tRNA-binding THUMP domain. CDAT8 is specific
for C deamination at position 8, requires only the acceptor
stem hairpin for activity, and belongs to a unique family within
the "cytidine deaminase–like" superfamily. The presence
of this C-to-U editing enzyme guarantees the proper folding
and functionality of all
M. kandleri tRNAs.
2 Department of Chemistry, Yale University, New Haven, CT 06520, USA.
* These authors contributed equally to this work.
To whom correspondence should be addressed. E-mail: lennart.randau{at}yale.edu (L.R.); dieter.soll{at}yale.edu (D.S.); yong.xiong{at}yale.edu (Y.X.)
