Expression strategies of the yeast retrotransposon Ty: a short sequence directs ribosomal frameshifting

ABSTRACT The yeast retrotransposon Ty1 encodes a 7-nucleotide RNA sequence that directs a programmed, +1 ribosomal frameshifting event required for Gag-Pol translation and retrotransposition. We report mutations that block frameshifting, which can be suppressed in cisby “transplanting” the frameshift signal to a position upstream of its native location. These “frameshift transplant” mutants transpose with only a modest decrease in efficiency, suggesting that the location of the frameshift signal in a functional Ty1 element may vary. The genomic architecture of Ty1 is such that Gag, Ty1 PR (PR), and the Gag-derived p4 peptide share a common sequence. The functional independence of the movement of the frameshift signal to a new location within the Ty1 element is used to unambiguously attribute the effect of mutations deleterious to transposition in this region of overlapping coding sequences to effects on the Ty1 (PR). This work defines the amino terminus of the Ty1 PR and introduces a new technique for studying viral genome organization.

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Faculty Opinions recommendation of Automated reconstruction of whole-genome phylogenies from short-sequence reads.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.718300624.793506810 ◽

2015 ◽

Author(s):

Alejandro Schaffer

Keyword(s):

Whole Genome ◽

Short Sequence

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Minireview: Peptide Analogs and Short Sequence Oligopeptides as Modulators of Skin Pigmentation

Current Topics in Medicinal Chemistry ◽

10.2174/1568026614666140601221519 ◽

2014 ◽

Vol 14 (12) ◽

pp. 1418-1424 ◽

Cited By ~ 10

Author(s):

Anan Ubeid ◽

Basil Hantash

Keyword(s):

Skin Pigmentation ◽

Short Sequence ◽

Peptide Analogs

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‘No Trickery with Montage’: On Reading a Sequence in Godard‘s Pierrot le fou

Film Studies ◽

10.7227/fs.5.2 ◽

2004 ◽

Vol 5 (1) ◽

pp. 8-29

Author(s):

Daniel Morgan

Keyword(s):

Short Sequence ◽

Single Event ◽

Actual Structure ◽

Close Analysis ◽

The Way

This paper is organised around an analysis of a short sequence from Godard‘s Pierrot le fou (1965). Although the sequence appears to be a series of repetitions, close analysis reveals it to be a single event presented in a carefully fragmented order. This unexpected fact generates questions about how to account for the relation between our initial beliefs about the organisation of the sequence and our knowledge of its actual structure. We come to see, in an intimate way, that reflection on the way we watch and understand film is one of the central themes of Godard‘s filmmaking.

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Modulation of Viral Programmed Ribosomal Frameshifting and Stop Codon Readthrough by the Host Restriction Factor Shiftless

Viruses ◽

10.3390/v13071230 ◽

2021 ◽

Vol 13 (7) ◽

pp. 1230

Author(s):

Sawsan Napthine ◽

Chris H. Hill ◽

Holly C. M. Nugent ◽

Ian Brierley

Keyword(s):

Rna Binding ◽

Mutational Analysis ◽

Stop Codon ◽

Leukemia Virus ◽

Size Exclusion ◽

Human Immunodeficiency Virus Replication ◽

Mobility Shift ◽

Ribosomal Frameshifting ◽

Stop Codon Readthrough

The product of the interferon-stimulated gene C19orf66, Shiftless (SHFL), restricts human immunodeficiency virus replication through downregulation of the efficiency of the viral gag/pol frameshifting signal. In this study, we demonstrate that bacterially expressed, purified SHFL can decrease the efficiency of programmed ribosomal frameshifting in vitro at a variety of sites, including the RNA pseudoknot-dependent signals of the coronaviruses IBV, SARS-CoV and SARS-CoV-2, and the protein-dependent stimulators of the cardioviruses EMCV and TMEV. SHFL also reduced the efficiency of stop-codon readthrough at the murine leukemia virus gag/pol signal. Using size-exclusion chromatography, we confirm the binding of the purified protein to mammalian ribosomes in vitro. Finally, through electrophoretic mobility shift assays and mutational analysis, we show that expressed SHFL has strong RNA binding activity that is necessary for full activity in the inhibition of frameshifting, but shows no clear specificity for stimulatory RNA structures.

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