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Base modification pattern at the wobble position of Xenopus selenocysteine tRNA(Sec).
Sturchler C, Lescure A, Keith G, Carbon P, Krol A.
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We examined the base modification pattern of Xenopus tRNA(Sec) using microinjection into Xenopus oocytes, with particular focus on the wobble base U34 at the first position of the anticodon. We found that U34 becomes modified to mcm5U34 (5-methylcarboxymethyluridine) in the oocyte cytoplasm in a rather complex manner. When the tRNA(Sec) gene is injected into Xenopus oocyte nuclei, psi 55 and m1A58 are readily obtained, but not mcm5U34. This will appear only upon cytoplasmic injection of the gene product arising from the first nuclear injection. In contrast, tRNA(Sec) produced by in vitro transcription with T7 RNA polymerase readily acquires i6A37, psi 55, m1A58, and mcm5U34. The latter is obtained after direct nuclear or cytoplasmic injections. It has been reported by others that mcm5Um, a 2'-O-methylated derivative of mcm5U34, also exists in rat and bovine tRNA(Sec). With both the gene product and the in vitro transcript, and using the sensitive RNase T2 assay, we were unable to detect under our conditions the presence of a dinucleotide carrying mcm5Um and that would be therefore refractory to hydrolysis. We showed that the unusual mcm5U acquisition pathway does not result from impairment of nucleocytoplasmic transport. Rather, these data can be interpreted to mean that the modification is performed by a tRNA(Sec) specific enzyme, limiting in the oocyte cytoplasm.
Amberg,
Editing does not exist for mammalian selenocysteine tRNAs.
1993, Pubmed
Amberg,
Editing does not exist for mammalian selenocysteine tRNAs.
1993,
Pubmed Baron,
Solution structure of selenocysteine-inserting tRNA(Sec) from Escherichia coli. Comparison with canonical tRNA(Ser).
1993,
Pubmed Baron,
The length of the aminoacyl-acceptor stem of the selenocysteine-specific tRNA(Sec) of Escherichia coli is the determinant for binding to elongation factors SELB or Tu.
1991,
Pubmed Böck,
Selenoprotein synthesis: an expansion of the genetic code.
1991,
Pubmed Carbon,
Transcription of the Xenopus laevis selenocysteine tRNA(Ser)Sec gene: a system that combines an internal B box and upstream elements also found in U6 snRNA genes.
1991,
Pubmed
,
Xenbase Diamond,
Structure and properties of a bovine liver UGA suppressor serine tRNA with a tryptophan anticodon.
1981,
Pubmed Diamond,
Dietary selenium affects methylation of the wobble nucleoside in the anticodon of selenocysteine tRNA([Ser]Sec).
1993,
Pubmed Droogmans,
Enzymatic 2'-O-methylation of the wobble nucleoside of eukaryotic tRNAPhe: specificity depends on structural elements outside the anticodon loop.
1986,
Pubmed
,
Xenbase Edqvist,
Identity elements for N2-dimethylation of guanosine-26 in yeast tRNAs.
1992,
Pubmed
,
Xenbase Grosjean,
Guanosine modifications in runoff transcripts of synthetic transfer RNA-Phe genes microinjected into Xenopus oocytes.
1990,
Pubmed
,
Xenbase Houssier,
Effect of uridine dethiolation in the anticodon triplet of tRNA(Glu) on its association with tRNA(Phe).
1988,
Pubmed Lee,
Transcription of Xenopus selenocysteine tRNA Ser (formerly designated opal suppressor phosphoserine tRNA) gene is directed by multiple 5'-extragenic regulatory elements.
1989,
Pubmed
,
Xenbase Lee,
Unique pathway of expression of an opal suppressor phosphoserine tRNA.
1987,
Pubmed
,
Xenbase Lee,
Identification of a selenocysteyl-tRNA(Ser) in mammalian cells that recognizes the nonsense codon, UGA.
1989,
Pubmed Lund,
Differential accumulation of U1 and U4 small nuclear RNAs during Xenopus development.
1987,
Pubmed
,
Xenbase Lund,
In vitro synthesis of vertebrate U1 snRNA.
1989,
Pubmed
,
Xenbase Myslinski,
Point mutations 5' to the tRNA selenocysteine TATA box alter RNA polymerase III transcription by affecting the binding of TBP.
1993,
Pubmed
,
Xenbase Myslinski,
Promoter strength and structure dictate module composition in RNA polymerase III transcriptional activator elements.
1993,
Pubmed
,
Xenbase Schön,
The selenocysteine-inserting opal suppressor serine tRNA from E. coli is highly unusual in structure and modification.
1989,
Pubmed Silberklang,
Use of in vitro 32P labeling in the sequence analysis of nonradioactive tRNAs.
1979,
Pubmed Steinberg,
Compilation of tRNA sequences and sequences of tRNA genes.
1993,
Pubmed Sturchler,
Unique secondary and tertiary structural features of the eucaryotic selenocysteine tRNA(Sec).
1993,
Pubmed
,
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