Inhibition of nonsense-mediated mRNA decay by antisense morpholino oligonucleotides restores functional expression of hERG nonsense and frameshift mutations in long-QT syndrome

Qiuming Gong, Matthew R. Stump, Zhengfeng Zhou

    Research output: Contribution to journalArticle

    22 Scopus citations


    Mutations in the human ether-a-go-go-related gene (hERG) cause long-QT syndrome type 2 (LQT2). We previously described a homozygous LQT2 nonsense mutation Q1070X in which the mutant mRNA is degraded by nonsense-mediated mRNA decay (NMD) leading to a severe clinical phenotype. The degradation of the Q1070X transcript precludes the expression of truncated but functional mutant channels. In the present study, we tested the hypothesis that inhibition of NMD can restore functional expression of LQT2 mutations that are targeted by NMD. We showed that inhibition of NMD by RNA interference-mediated knockdown of UPF1 increased Q1070X mutant channel protein expression and hERG current amplitude. More importantly, we found that specific inhibition of downstream intron splicing by antisense morpholino oligonucleotides prevented NMD of the Q1070X mutant mRNA and restored the expression of functional Q1070X mutant channels. The restoration of functional expression by antisense morpholino oligonucleotides was also observed in LQT2 frameshift mutations. Our findings suggest that inhibition of NMD by antisense morpholino oligonucleotides may be a potential therapeutic approach for some LQT2 patients carrying nonsense and frameshift mutations.

    Original languageEnglish (US)
    Pages (from-to)223-229
    Number of pages7
    JournalJournal of molecular and cellular cardiology
    Issue number1
    StatePublished - Jan 1 2011



    • Morpholino, long-QT syndrome
    • Nonsense-mediated mRNA decay
    • Patch clamp
    • Potassium channel

    ASJC Scopus subject areas

    • Molecular Biology
    • Cardiology and Cardiovascular Medicine

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