Nonsense-mediated decay mutants do not affect programmed -1 frameshifting.
Sequences in certain mRNAs program the ribosome to undergo a noncanonical translation event, translational frameshifting, translational hopping, or termination readthrough. These sequences are termed recoding sites, because they cause the ribosome to change temporarily its coding rules. Cis and trans-acting factors sensitively modulate the efficiency of recoding events. In an attempt to quantitate the effect of these factors we have developed a dual-reporter vector using the lacZ and luc genes to directly measure recoding efficiency. We were able to confirm the effect of several factors that modulate frameshift or readthrough efficiency at a variety of sites. Surprisingly, we were not able to confirm that the complex of factors termed the surveillance complex regulates translational frameshifting. This complex regulates degradation of nonsense codon-containing mRNAs and we confirm that it also affects the efficiency of nonsense suppression. Our data suggest that the surveillance complex is not a general regulator of translational accuracy, but that its role is closely tied to the translational termination and initiation processes.
Bidou
L
L
Institut de Génétique et Microbiologie, Université Paris-Sud, France.
Stahl
G
G
Hatin
I
I
Namy
O
O
Rousset
J P
JP
Farabaugh
P J
PJ
D000595:Amino Acid Sequence; D001483:Base Sequence; D003062:Codon; D004926:Escherichia coli / Q000378:metabolism; D016368:Frameshift Mutation; D017930:Genes, Reporter; D008969:Molecular Sequence Data; D009154:Mutation; D010957:Plasmids; D014176:Protein Biosynthesis; D012441:Saccharomyces cerevisiae / Q000235:genetics; D015533:Transcriptional Activation
D003062:Codon