RNA-methyltransferase TrmA is a dual-specific enzyme responsible for C5-methylation of uridine in both tmRNA and tRNA.
RNA Biol
; 10(4): 572-8, 2013 Apr.
Article
en En
| MEDLINE
| ID: mdl-23603891
ABSTRACT
In bacteria, trans-translation rescues stalled ribosomes by the combined action of tmRNA (transfer-mRNA) and its associated protein SmpB. The tmRNA 5' and 3' ends fold into a tRNA-like domain (TLD), which shares structural and functional similarities with tRNAs. As in tRNAs, the UUC sequence of the T-arm of the TLD is post-transcriptionally modified to m (5)UψC. In tRNAs of gram-negative bacteria, formation of m (5)U is catalyzed by the SAM-dependent methyltransferase TrmA, while formation of m (5)U at two different positions in rRNA is catalyzed by distinct site-specific methyltransferases RlmC and RlmD. Here, we show that m (5)U formation in tmRNAs is exclusively due to TrmA and should be considered as a dual-specific enzyme. The evidence comes from the lack of m (5)U in purified tmRNA or TLD variants recovered from an Escherichia coli mutant strain deleted of the trmA gene. Detection of m (5)U in RNA was performed by NMR analysis.
Palabras clave
Texto completo:
1
Base de datos:
MEDLINE
Asunto principal:
ARNt Metiltransferasas
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Uridina
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ARN Bacteriano
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ARN de Transferencia
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Proteínas de Escherichia coli
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Escherichia coli
Idioma:
En
Revista:
RNA Biol
Asunto de la revista:
BIOLOGIA MOLECULAR
Año:
2013
Tipo del documento:
Article