| DOI | Trouver le DOI : https://doi.org/10.1016/j.bbapap.2009.03.012 |
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| Auteur | Rechercher : Cheng, Jenny1; Rechercher : Koukiekolo, Roger2; Rechercher : Kieliszkiewicz, Katarzyna; Rechercher : Sagan, Selena M.1; Rechercher : Pezacki, John Paul1 |
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| Affiliation | - Conseil national de recherches du Canada. Institut Steacie des sciences moléculaires du CNRC
- Conseil national de recherches du Canada. Initiative en génomique et en santé du CNRC
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| Format | Texte, Article |
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| Sujet | carnation italian ringspot virus; CIRV; protein; cysteine alkylation; mutagenesis; amino acid; nanomolar; circular dichroism; siRNA; thermostability |
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| Résumé | Carnation Italian Ringspot virus (CIRV) has evolved a protein called p19 that acts as a suppressor of RNA silencing in the host cell and aids in viral persistence. This protein has been shown to be sensitive to cysteine alkylation resulting in a reduction in its ability to bind to short-interfering RNA (siRNA). To determine the sites within the protein that are sensitive to alkylation, we systematically tested the functional role of each cysteine residue using site-directed mutagenesis. Variants of the p19 protein were created at locations C110, C134 and C160 where the cysteines were replaced by an inert amino acid such as serine or isoleucine. The results from activity measurements of the purified mutant p19 proteins indicate that the mutants maintain the ability to bind siRNAs with nanomolar affinity, however, their stabilities, as measured by circular dichroism (CD), vary. Functional studies in the presence of the cysteine alkylating agent N-ethylmaleimide (NEM) indicated that p19's ability to bind siRNAs and act as a suppressor of RNA silencing is sensitive to alkylation at all three cysteine residues with the maximum effects occurring when C110 and C134 are both alkylated. These results suggest that the role of the cysteine amino acid conservation is likely to preserve the overall structural integrity of p19 for optimal thermostability and subsequent siRNA-binding activity. We find that p19 function is maximally compromised at high levels of thiol alkylation or in an oxidizing environment. |
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| Date de publication | 2009 |
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| Dans | |
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| Langue | anglais |
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| Publications évaluées par des pairs | Oui |
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| Publication du CNRC | Cette publication n’est pas du CNRCCe sont des publications qui ont été rédigées par un auteur du CNRC, mais avant que celui-ci soit employé du CNRC. |
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| Numéro NPARC | 16080399 |
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| Exporter la notice | Exporter en format RIS |
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| Signaler une correction | Signaler une correction (s'ouvre dans un nouvel onglet) |
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| Identificateur de l’enregistrement | ac318876-f7b1-4121-a259-212fd4b863a2 |
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| Enregistrement créé | 2010-09-21 |
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| Enregistrement modifié | 2020-04-16 |
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