RRC ID 53766
著者 Sakai Y, Miyauchi K, Kimura S, Suzuki T.
タイトル Biogenesis and growth phase-dependent alteration of 5-methoxycarbonylmethoxyuridine in tRNA anticodons.
ジャーナル Nucleic Acids Res
Abstract Post-transcriptional modifications at the anticodon first (wobble) position of tRNA play critical roles in precise decoding of genetic codes. 5-carboxymethoxyuridine (cmo(5)U) and its methyl ester derivative 5-methoxycarbonylmethoxyuridine (mcmo(5)U) are modified nucleosides found at the anticodon wobble position in several tRNAs from Gram-negative bacteria. cmo(5)U and mcmo(5)U facilitate non-Watson-Crick base pairing with guanosine and pyrimidines at the third positions of codons, thereby expanding decoding capabilities. By mass spectrometric analyses of individual tRNAs and a shotgun approach of total RNA from Escherichia coli, we identified mcmo(5)U as a major modification in tRNA(Ala1), tRNA(Ser1), tRNA(Pro3) and tRNA(Thr4); by contrast, cmo(5)U was present primarily in tRNA(Leu3) and tRNA(Val1). In addition, we discovered 5-methoxycarbonylmethoxy-2'-O-methyluridine (mcmo(5)Um) as a novel but minor modification in tRNA(Ser1). Terminal methylation frequency of mcmo(5)U in tRNA(Pro3) was low (≈30%) in the early log phase of cell growth, gradually increased as growth proceeded and reached nearly 100% in late log and stationary phases. We identified CmoM (previously known as SmtA), an AdoMet-dependent methyltransferase that methylates cmo(5)U to form mcmo(5)U. A luciferase reporter assay based on a +1 frameshift construct revealed that terminal methylation of mcmo(5)U contributes to the decoding ability of tRNA(Ala1).
巻・号 44(2)
ページ 509-23
公開日 2016-1-29
DOI 10.1093/nar/gkv1470
PII gkv1470
PMID 26681692
PMC PMC4737166
MeSH Amino Acid Sequence Anticodon / chemistry Anticodon / metabolism* Base Pairing Codon / chemistry Codon / metabolism* Escherichia coli / genetics* Escherichia coli / metabolism Gammaproteobacteria / genetics Gammaproteobacteria / metabolism Gene Expression Regulation, Bacterial Genetic Code Models, Molecular Molecular Sequence Data Nucleic Acid Conformation RNA, Bacterial / chemistry RNA, Bacterial / metabolism* RNA, Transfer / chemistry RNA, Transfer / metabolism* Ribosomes / genetics Ribosomes / metabolism Sequence Alignment Uridine / analogs & derivatives Uridine / metabolism*
IF 11.502
引用数 16
リソース情報
原核生物(大腸菌)