AAV-delivered suppressor tRNA overcomes a nonsense mutation in mice
Horae Gene Therapy Center; Program in Molecular Medicine; Bioinformatics Core; Mass Spectrometry Facility; Department of Biochemistry and Molecular Pharmacology; Department of Microbiology and Physiological Systems; Department of Pathology; RNA Therapeutics Institute
Genetics and Genomics | Therapeutics
Gene therapy is a potentially curative medicine for many currently untreatable diseases, and recombinant adeno-associated virus (rAAV) is the most successful gene delivery vehicle for in vivo applications(1-3). However, rAAV-based gene therapy suffers from several limitations, such as constrained DNA cargo size and toxicities caused by non-physiological expression of a transgene(4-6). Here we show that rAAV delivery of a suppressor tRNA (rAAV.sup-tRNA) safely and efficiently rescued a genetic disease in a mouse model carrying a nonsense mutation, and effects lasted for more than 6 months after a single treatment. Mechanistically, this was achieved through a synergistic effect of premature stop codon readthrough and inhibition of nonsense-mediated mRNA decay. rAAV.sup-tRNA had a limited effect on global readthrough at normal stop codons and did not perturb endogenous tRNA homeostasis, as determined by ribosome profiling and tRNA sequencing, respectively. By optimizing the AAV capsid and the route of administration, therapeutic efficacy in various target tissues was achieved, including liver, heart, skeletal muscle and brain. This study demonstrates the feasibility of developing a toolbox of AAV-delivered nonsense suppressor tRNAs operating on premature termination codons (AAV-NoSTOP) to rescue pathogenic nonsense mutations and restore gene function under endogenous regulation. As nonsense mutations account for 11% of pathogenic mutations, AAV-NoSTOP can benefit a large number of patients. AAV-NoSTOP obviates the need to deliver a full-length protein-coding gene that may exceed the rAAV packaging limit, elicit adverse immune responses or cause transgene-related toxicities. It therefore represents a valuable addition to gene therapeutics.
Gene therapy, Genetic vectors
DOI of Published Version
Wang J, Zhang Y, Mendonca CA, Yukselen O, Muneeruddin K, Ren L, Liang J, Zhou C, Xie J, Li J, Jiang Z, Kucukural A, Shaffer SA, Gao G, Wang D. AAV-delivered suppressor tRNA overcomes a nonsense mutation in mice. Nature. 2022 Apr;604(7905):343-348. doi: 10.1038/s41586-022-04533-3. Epub 2022 Mar 23. PMID: 35322228. Link to article on publisher's site
Wang J, Zhang Y, Mendonca CA, Yukselen O, Muneeruddin K, Ren L, Liang J, Zhou C, Xie J, Li J, Jiang Z, Kucukural A, Shaffer SA, Gao G, Wang D. (2022). AAV-delivered suppressor tRNA overcomes a nonsense mutation in mice. Program in Bioinformatics and Integrative Biology Publications. https://doi.org/10.1038/s41586-022-04533-3. Retrieved from https://escholarship.umassmed.edu/bioinformatics_pubs/175