Nucleic Acids Research, Vol 26, Issue 11 2708-2714, Copyright © 1998 by Oxford University Press
K Akama, Y Yukawa, M Sugiura and I Small
A nuclear gene coding for tRNAHis from Arabidopsis has been reported to
contain C54in the TPsiC loop, although the corresponding nucleotide is an
invariant U or a derivative in nearly all other tRNAs. The only previously
reported plant cytosolic tRNAHis sequence, from lupin, has U54. To
re-examine plant cytosolic tRNAsHis and their genes we have used DNA and
RNA sequence analyses, restriction enzyme digestion of PCR- amplified tRNA
genes, RNA hybridization and in vivo aminoacylation assays. Our results
suggest that Arabidopsis nuclear tRNAHis genes ubiquitously contain C54, as
do those from tobacco, lupin and pea. The C54 nucleotide is maintained in
the mature tRNAHis, which is aminoacylated in vivo , but to a relatively
low level compared with other tRNAs examined. Finally, it was shown that an
Arabidopsis tRNAHis gene with T54in place of C54 is over 5-fold more
transcriptionally active than the wild-type gene using an in vitro system
derived from plant nuclei. A possible role for this apparently sub-optimal
tRNAHis sequence is suggested.
ARTICLES
Plant cytosolic tRNAHis possesses an exceptional C54 in the canonical TPsiC loop
Department of Biological Science, Shimane University, Matsue 690, Japan. akama@life.shimane-u.ac.jp
![]()
CiteULike
Connotea
Del.icio.us What's this?