Nucleic Acids Research Advance Access published online on November 19, 2007
Nucleic Acids Research, doi:10.1093/nar/gkm1033
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Molecular Biology |
Ex vivo correction of selenoprotein N deficiency in rigid spine muscular dystrophy caused by a mutation in the selenocysteine codon
1Architecture et Réactivité de l’ARN, Université Louis Pasteur de Strasbourg, CNRS, 67084 Strasbourg, France, 2Inserm, U582, Institut de Myologie, Paris, France, 3Université Pierre et Marie Curie-Paris 6, UMR-S582, IFR14, Paris, France, 4AP-HP, Groupe Hospitalier Pitié-Salpêtrière, UF Cardiogénétique et Myogénétique, Service de Biochimie Métabolique, Paris, France and 5Clinique Sainte Odile, Strasbourg, France
*To whom correspondence should be addressed. Tel: 33 3 88 41 70 80; Fax: 33 3 88 60 22 18; Email: a.lescure{at}ibmc.u-strasbg.fr
Received September 17, 2007. Revised October 22, 2007. Accepted October 29, 2007.
Premature termination of translation due to nonsense mutations is a frequent cause of inherited diseases. Therefore, many efforts were invested in the development of strategies or compounds to selectively suppress this default. Selenoproteins are interesting candidates considering the idiosyncrasy of the amino acid selenocysteine (Sec) insertion mechanism. Here, we focused our studies on SEPN1, a selenoprotein gene whose mutations entail genetic disorders resulting in different forms of muscular diseases. Selective correction of a nonsense mutation at the Sec codon (UGA to UAA) was undertaken with a corrector tRNASec that was engineered to harbor a compensatory mutation in the anticodon. We demonstrated that its expression restored synthesis of a full-length selenoprotein N both in HeLa cells and in skin fibroblasts from a patient carrying the mutated Sec codon. Readthrough of the UAA codon was effectively dependent on the Sec insertion machinery, therefore being highly selective for this gene and unlikely to generate off-target effects. In addition, we observed that expression of the corrector tRNASec stabilized the mutated SEPN1 transcript that was otherwise more subject to degradation. In conclusion, our data provide interesting evidence that premature termination of translation due to nonsense mutations is amenable to correction, in the context of the specialized selenoprotein synthesis mechanism.
Present address: M. Rederstorff, Innsbruck Biocenter, Division of Genomics and RNomics, Innsbruck Medical University, Austria.
The authors wish it to be known that, in their opinion, the first two authors should be regarded as joint First Authors.