L-MPZ, a Novel Isoform of Myelin P0, Is Produced by 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.

Download Full-text

Developing DMD therapeutics: a review of the effectiveness of small molecules, stop-codon readthrough, dystrophin gene replacement, and exon-skipping therapies

Expert Opinion on Investigational Drugs ◽

10.1080/13543784.2021.1868434 ◽

2021 ◽

pp. 1-10

Author(s):

Omar Sheikh ◽

Toshifumi Yokota

Keyword(s):

Small Molecules ◽

Stop Codon ◽

Exon Skipping ◽

Dystrophin Gene ◽

Gene Replacement ◽

Stop Codon Readthrough

Download Full-text

Aminoglycoside-induced mutation suppression (stop codon readthrough) as a therapeutic strategy for Duchenne muscular dystrophy

Therapeutic Advances in Neurological Disorders ◽

10.1177/1756285610388693 ◽

2010 ◽

Vol 3 (6) ◽

pp. 379-389 ◽

Cited By ~ 49

Author(s):

Vinod Malik ◽

Louise R. Rodino-Klapac ◽

Laurence Viollet ◽

Jerry R. Mendell

Keyword(s):

Duchenne Muscular Dystrophy ◽

Muscular Dystrophy ◽

Therapeutic Strategy ◽

Stop Codon ◽

Induced Mutation ◽

Stop Codon Readthrough

Download Full-text

The functional readthrough extension of malate dehydrogenase reveals a modification of the genetic code

Open Biology ◽

10.1098/rsob.160246 ◽

2016 ◽

Vol 6 (11) ◽

pp. 160246 ◽

Cited By ~ 15

Author(s):

Julia Hofhuis ◽

Fabian Schueren ◽

Christopher Nötzel ◽

Thomas Lingner ◽

Jutta Gärtner ◽

...

Keyword(s):

Malate Dehydrogenase ◽

Stop Codon ◽

Protein Isoforms ◽

Translational Readthrough ◽

Peroxisomal Targeting ◽

Codon Context ◽

Targeting Signal ◽

Stop Codon Readthrough ◽

Insight Into ◽

Actual Ratio

Translational readthrough gives rise to C-terminally extended proteins, thereby providing the cell with new protein isoforms. These may have different properties from the parental proteins if the extensions contain functional domains. While for most genes amino acid incorporation at the stop codon is far lower than 0.1%, about 4% of malate dehydrogenase (MDH1) is physiologically extended by translational readthrough and the actual ratio of MDH1x (e x tended protein) to ‘normal' MDH1 is dependent on the cell type. In human cells, arginine and tryptophan are co-encoded by the MDH1x UGA stop codon. Readthrough is controlled by the 7-nucleotide high-readthrough stop codon context without contribution of the subsequent 50 nucleotides encoding the extension. All vertebrate MDH1x is directed to peroxisomes via a hidden peroxisomal targeting signal (PTS) in the readthrough extension, which is more highly conserved than the extension of lactate dehydrogenase B. The hidden PTS of non-mammalian MDH1x evolved to be more efficient than the PTS of mammalian MDH1x. These results provide insight into the genetic and functional co-evolution of these dually localized dehydrogenases.

Download Full-text

Polypeptide chain termination and stop codon readthrough on eukaryotic ribosomes

Ergebnisse der Physiologie ◽

10.1007/s10254-005-0039-7 ◽

2005 ◽

Cited By ~ 1

Author(s):

S. Rospert ◽

M. Rakwalska ◽

Y. Dubaquié

Keyword(s):

Polypeptide Chain ◽

Stop Codon ◽

Chain Termination ◽

Stop Codon Readthrough

Download Full-text

uS3/Rps3 controls fidelity of translation termination and programmed stop codon readthrough in co-operation with eIF3

Nucleic Acids Research ◽

10.1093/nar/gkz929 ◽

2019 ◽

Vol 47 (21) ◽

pp. 11326-11343 ◽

Cited By ~ 1

Author(s):

Kristýna Poncová ◽

Susan Wagner ◽

Myrte Esmeralda Jansen ◽

Petra Beznosková ◽

Stanislava Gunišová ◽

...

Keyword(s):

Translational Control ◽

Stop Codon ◽

Translation Termination ◽

Translation Initiation Factor ◽

Initiation Factor ◽

Eukaryotic Translation ◽

C Terminus ◽

Context Specific ◽

Stop Codon Readthrough

Abstract Ribosome was long considered as a critical yet passive player in protein synthesis. Only recently the role of its basic components, ribosomal RNAs and proteins, in translational control has begun to emerge. Here we examined function of the small ribosomal protein uS3/Rps3, earlier shown to interact with eukaryotic translation initiation factor eIF3, in termination. We identified two residues in consecutive helices occurring in the mRNA entry pore, whose mutations to the opposite charge either reduced (K108E) or increased (R116D) stop codon readthrough. Whereas the latter increased overall levels of eIF3-containing terminating ribosomes in heavy polysomes in vivo indicating slower termination rates, the former specifically reduced eIF3 amounts in termination complexes. Combining these two mutations with the readthrough-reducing mutations at the extreme C-terminus of the a/Tif32 subunit of eIF3 either suppressed (R116D) or exacerbated (K108E) the readthrough phenotypes, and partially corrected or exacerbated the defects in the composition of termination complexes. In addition, we found that K108 affects efficiency of termination in the termination context-specific manner by promoting incorporation of readthrough-inducing tRNAs. Together with the multiple binding sites that we identified between these two proteins, we suggest that Rps3 and eIF3 closely co-operate to control translation termination and stop codon readthrough.

Download Full-text