In vitro codon-reading specificities of unmodified tRNA molecules with different anticodons on the sequence background of Escherichia coli tRNASer.
The codon-reading properties of wobble-position variants of the unmodified form of Escherichia coli tRNASer1 (the UGA anticodon) were measured in a cell-free translation system. Two variants, with the AGA and CGA anticodons, each exclusively read a single codon, UCU and UCG, respectively. The only case of efficient wobbling occurred with the variant with the GGA anticodon, which reads the UCU codon in addition to the UCC codon. Surprisingly, this wobble reading is more efficient than the Watson-Crick reading by the variant with the AGA anticodon. Furthermore, we prepared tRNA variants with AA, UC, and CU, instead of GA, in the second and third positions and measured their relative efficiencies in the reading of codons starting with UU, GA, and AG, respectively. The specificity concerning the wobble position is essentially the same as that in the case of the codons starting with UC.
Takai
K
K
Department of Industrial Chemistry, Chiba Institute of Technology, 2-17-1, Tsudanuma, Narashino, Chiba, 275-0016, Japan.
Takaku
H
H
Yokoyama
S
S
D000595:Amino Acid Sequence; D000926:Anticodon / Q000235:genetics*; D020029:Base Pairing / Q000235:genetics; D001483:Base Sequence; D001667:Binding, Competitive; D003062:Codon / Q000235:genetics*; D004926:Escherichia coli / Q000235:genetics*; D005815:Genetic Code; D007700:Kinetics; D008969:Molecular Sequence Data; D009154:Mutation; D014176:Protein Biosynthesis; D012323:RNA Processing, Post-Transcriptional; D012362:RNA, Transfer, Ser / Q000235:genetics* / Q000378:metabolism; D012694:Serine / Q000235:genetics / Q000378:metabolism; D013816:Thermodynamics
D000926:Anticodon; D003062:Codon; D012362:RNA, Transfer, Ser; D012694:Serine