E. coli ribosomes re-phase on retroviral frameshift signals at rates ranging from 2 to 50 percent.
Many retroviruses express gag-pol or gag-pro-pol polypeptides by coupling their translation from overlapping reading frames with -1 ribosomal frameshifts. Here, we show that the well-known ribosomal frameshift signals found in retroviral mRNA will provoke Escherichia coli ribosomes to shift frame in the same manner as their eukaryotic counterparts. Ribosomes of E. coli respond in vivo to both the tandem slippery codons present at the retroviral frameshift site and the 3' flanking sequence. Slight alteration of the mouse mammary tumor virus gag-pro frameshift site from A-AAA-AAC to A-AAA-AAG boosts the level of frameshifting in E. coli to over 50%. This suggests that A-AAA-AAG, and its slippery relatives, may be utilized by E. coli genes as sites of high-level ribosomal frameshifting. This observed conservation of response to retroviral frameshift signals affords new avenues to dissect the mechanism of ribosomal frameshifting evoked by these mRNA sequences.
Weiss
R B
RB
Howard Hughes Medical Institute, University of Utah School of Medicine, Salt Lake City 84132.
Dunn
D M
DM
Shuh
M
M
Atkins
J F
JF
Gesteland
R F
RF
D001483:Base Sequence; D003062:Codon; D004926:Escherichia coli / Q000378:metabolism*; D015685:Fusion Proteins, gag-pol / Q000096:biosynthesis / Q000235:genetics*; D015967:Gene Expression Regulation, Viral; D015683:Gene Products, gag / Q000096:biosynthesis / Q000235:genetics*; D005807:Genes, Overlapping; D005813:Genes, Synthetic; D005814:Genes, Viral; D015497:HIV-1 / Q000235:genetics*; D008324:Mammary Tumor Virus, Mouse / Q000235:genetics*; D008969:Molecular Sequence Data; D009690:Nucleic Acid Conformation; D014176:Protein Biosynthesis; D012333:RNA, Messenger / Q000235:genetics; D012367:RNA, Viral / Q000235:genetics; D011993:Recombinant Fusion Proteins / Q000096:biosynthesis; D012270:Ribosomes / Q000378:metabolism*
D003062:Codon; D015685:Fusion Proteins, gag-pol; D015683:Gene Products, gag; D012333:RNA, Messenger; D012367:RNA, Viral; D011993:Recombinant Fusion Proteins