RRC ID 35546
Author Miyauchi K, Kimura S, Suzuki T.
Title A cyclic form of N6-threonylcarbamoyladenosine as a widely distributed tRNA hypermodification.
Journal Nat Chem Biol
Abstract N(6)-threonylcarbamoyladenosine (t(6)A) is a universally conserved, essential modified nucleoside found in transfer RNAs (tRNAs) responsible for ANN codons in all three domains of life. t(6)A has a crucial role in maintaining decoding accuracy during protein synthesis. The presence of t(6)A in cellular tRNAs has been well documented for more than four decades. However, under conditions optimized for nucleoside preparation, we detected little t(6)A in tRNAs from Escherichia coli. Instead, we identified a new modified base named 'cyclic t(6)A' (ct(6)A), which is a cyclized active ester with an oxazolone ring. An E1-like enzyme, CsdL (renamed as TcdA), which catalyzes ATP-dependent dehydration of t(6)A to form ct(6)A, was also identified. Two yeast homologs of tcdA, YHR003C (TCD1) and YKL027W (TCD2), were required for ct(6)A formation and respiratory cell growth. ct(6)A was involved in promoting decoding efficiency. Structural modeling suggests that ct(6)A recognizes the first adenine base of ANN codon at the ribosomal A site.
Volume 9(2)
Pages 105-11
Published 2013-2-1
DOI 10.1038/nchembio.1137
PII nchembio.1137
PMID 23242255
MeSH Adenosine / analogs & derivatives* Adenosine / chemistry Adenosine Triphosphate / chemistry Catalysis Codon Escherichia coli / enzymology Escherichia coli Proteins / metabolism Hydrolysis Magnetic Resonance Spectroscopy Models, Chemical Models, Genetic Nucleic Acid Conformation Oxazolone / chemistry Protein Biosynthesis Protein Structure, Secondary RNA, Transfer / chemistry* Recombinant Proteins / chemistry Ubiquitin-Activating Enzymes / metabolism
IF 12.154
Times Cited 94
Prokaryotes E. coli NA