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Nonsense-mediated decay mutants do not affect programmed -1 frameshifting.

L Bidou·G Stahl·I Hatin·O Namy·J P Rousset·P J Farabaugh
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Abstract

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.

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Amino Acid SequenceBase SequenceCodonEscherichia coliFrameshift MutationGenes, ReporterMolecular Sequence DataMutationPlasmidsProtein BiosynthesisSaccharomyces cerevisiaeTranscriptional ActivationJournal ArticleResearch Support, Non-U.S. Gov'tResearch Support, U.S. Gov't, P.H.S.

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L Bidou, G Stahl, I Hatin, O Namy, J P Rousset, P J Farabaugh. 2000. Nonsense-mediated decay mutants do not affect programmed -1 frameshifting.. https://doi.org/10.1017/s1355838200000443

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