Mutations at U2555, a tRNA-protected base in 23S rRNA, affect translational fidelity.
A plasmid carrying a mutation in the highly conserved base U2555 in Escherichia coli 23S rRNA was isolated by selecting for suppression of the -1 frameshift mutation trpE91. U2555 is normally protected in chemical footprinting experiments by the aminoacyl residue of A-site-bound tRNA. Substitution of U2555 by adenine or guanine (but not by cytosine) increased readthrough of all three stop codons and +1 and -1 frameshifting. These effects on translational fidelity demonstrate the importance of U2555 for selection of the correct tRNA at the ribosomal A site.
O'Connor
M
M
Section of Biochemistry, Brown University, Providence, RI 02912.
Dahlberg
A E
AE
D000595:Amino Acid Sequence; D001482:Base Composition; D001483:Base Sequence; D003062:Codon / Q000235:genetics; D017124:Conserved Sequence; D004926:Escherichia coli / Q000235:genetics / Q000378:metabolism* / Q000528:radiation effects; D016368:Frameshift Mutation; D007613:Kanamycin Resistance / Q000235:genetics; D008969:Molecular Sequence Data; D016296:Mutagenesis; D016254:Mutagenesis, Insertional; D009690:Nucleic Acid Conformation; D009876:Operon; D014176:Protein Biosynthesis; D011815:R Factors; D012338:RNA, Ribosomal, 23S / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism*; D015183:Restriction Mapping; D014466:Ultraviolet Rays; D014498:Uracil; D001616:beta-Galactosidase / Q000235:genetics / Q000378:metabolism
D003062:Codon; D012338:RNA, Ribosomal, 23S; D014498:Uracil; D001616:beta-Galactosidase