Abstract
Bifunctional antisense oligonucleotide (AON) is a specially designed AON to regulate pre-messenger RNA (pre-mRNA) splicing of a target gene. It is composed of two domains. The antisense domain contains sequences complementary to the target gene. The tail domain includes RNA sequences that recruit RNA binding proteins which may act positively or negatively in pre-mRNA splicing. This approach can be designed as targeted oligonucleotide enhancers of splicing, named TOES, for exon inclusion; or as targeted oligonucleotide silencers of splicing, named TOSS, for exon skipping. Here, we provide detailed methods for the design of TOES for exon inclusion, using SMN2 exon 7 splicing as an example. A number of annealing sites and the tail sequences previously published are listed. We also present methodology of assessing the effects of TOES on exon inclusion in fibroblasts cultured from a SMA patient. The effects of TOES on SMN2 exon 7 splicing were validated at RNA level by PCR and quantitative real-time PCR, and at protein level by western blotting.
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References
- Dominski Z, Kole R (1993) Antisense oligonucleotides. Proc Natl Acad Sci U S A 90:8673–8677 doi: 10.1073/pnas.90.18.8673. [DOI] [PMC free article] [PubMed]
- Mitrpant C, Porensky P, Zhou H, Price L, Muntoni F, Fletcher S et al (2013) Improved antisense oligonucleotide design to suppress aberrant SMN2 gene transcript processing: towards a treatment for spinal muscular atrophy. PLoS One 8:2–11 doi: 10.1371/journal.pone.0062114. [DOI] [PMC free article] [PubMed]
- Hua Y, Sahashi K, Rigo F, Hung G, Horev G, Bennett F et al (2011) Peripheral SMN restoration is essential for long-term rescue of a severe spinal muscular atrophy mouse model. Nature 478:123–126 doi: 10.1038/nature10485. [DOI] [PMC free article] [PubMed]
- Zhou H, Janghra N, Mitrpant C, Dickinson R, Anthony K, Price L et al (2013) A novel morpholino oligomer targeting ISS-N1 improves rescue of severe spinal muscular atrophy transgenic mice. Hum Gene Ther 24:331–342 doi: 10.1089/hum.2012.211. [DOI] [PMC free article] [PubMed]
- Singh NK, Singh NN, Androphy EJ, Eliot J, Singh RN (2006) Splicing of a critical exon of human Survival Motor Neuron is regulated by a unique silencer element located in the last intron. Mol Cell Biol 26:1333–1346 doi: 10.1128/MCB.26.4.1333-1346.2006. [DOI] [PMC free article] [PubMed]
- Mercuri E, Darras BT, Chiriboga CA, Day JW, Campbell C, Connolly AM et al (2018) Nusinersen versus sham control in later-onset spinal muscular atrophy. N Engl J Med 378:625–635 doi: 10.1056/NEJMoa1710504. [DOI] [PubMed]
- Finkel RS, Mercuri E, Darras BT, Connolly NL, Kuntz J, Kirschner CA et al (2017) Nusinersen versus sham control in infantile-onset spinal muscular atrophy. N Engl J Med 377:1723–1732 doi: 10.1056/NEJMoa1702752. [DOI] [PubMed]
- Hoy SM (2017) Nusinersen: first global approval. Drugs 77:473–479 doi: 10.1007/s40265-017-0711-7. [DOI] [PubMed]
- Cirak S, Arechavala-Gomeza V, Guglieri M, Feng L, Torelli S, Anthony K et al (2011) Exon skipping and dystrophin restoration in patients with Duchenne muscular dystrophy after systemic phosphorodiamidate morpholino oligomer treatment: an open-label, phase 2, dose-escalation study. Lancet 378:595–605 doi: 10.1016/S0140-6736(11)60756-3. [DOI] [PMC free article] [PubMed]
- Kinali M, Arechavala-Gomeza V, Feng L, Cirak S, Hunt D, Adkin C et al (2009) Local restoration of dystrophin expression with the morpholino oligomer AVI-4658 in Duchenne muscular dystrophy: a single-blind, placebo-controlled, dose-escalation, proof-of-concept study. Lancet Neurol 8:918–928 doi: 10.1016/S1474-4422(09)70211-X. [DOI] [PMC free article] [PubMed]
- Aartsma-Rus A, Corey DR (2020) The 10th oligonucleotide therapy approved: golodirsen for Duchenne muscular dystrophy. Nucl Acids Ther 30:67. https://doi.org/10.1089/nat.2020.0845 doi: 10.1089/nat.2020.0845. [DOI] [PMC free article] [PubMed]
- Frank DE, Schnell FJ, Akana C, El-Husayni SH, Desjardins CA, Morgan J et al (2020) Increased dystrophin production with golodirsen in patients with Duchenne muscular dystrophy. Neurology 94:e2270. https://doi.org/10.1212/WNL.0000000000009233 doi: 10.1212/WNL.0000000000009233. [DOI] [PMC free article] [PubMed]
- Heo YA (2020) Golodirsen: first approval. Drugs 80:329–333 doi: 10.1007/s40265-020-01267-2. [DOI] [PubMed]
- Skordis LA, Dunckley MG, Yue B, Eperon IC, Muntoni F (2003) Bifunctional antisense oligonucleotides provide a trans-acting splicing enhancer that stimulates SMN2 gene expression in patient fibroblasts. Proc Natl Acad Sci U S A 100:4114–4119 doi: 10.1073/pnas.0633863100. [DOI] [PMC free article] [PubMed]
- Cartegni L, Krainer AR (2003) Correction of disease-associated exon skipping by synthetic exon-specific activators. Nat Struct Biol 10:120–125 doi: 10.1038/nsb887. [DOI] [PubMed]
- Owen N, Zhou H, Malygin AA, Sangha J, Smith LD, Muntoni F et al (2011) Design principles for bifunctional targeted oligonucleotide enhancers of splicing. Nucl Acids Res 39:7194–7208 doi: 10.1093/nar/gkr152. [DOI] [PMC free article] [PubMed]
- Brosseau JP, Lucier JF, Lamarche AA, Shkreta L, Gendron D, Lapointe E et al (2014) Redirecting splicing with bifunctional oligonucleotides. Nucl Acids Res 42:e40 doi: 10.1093/nar/gkt1287. [DOI] [PMC free article] [PubMed]
- Baughan TD, Dickson A, Osman EY, Lorson CL (2009) Delivery of bifunctional RNAs that target an intronic repressor and increase SMN levels in an animal model of spinal muscular atrophy. Hum Mol Genet 18:1600–1611 doi: 10.1093/hmg/ddp076. [DOI] [PMC free article] [PubMed]
- Osman EY, Yen PF, Lorson CL (2012) Bifunctional RNAs targeting the intronic splicing silencer N1 increase SMN levels and reduce disease severity in an animal model of spinal muscular atrophy. Mol Ther 20:119–126 doi: 10.1038/mt.2011.232. [DOI] [PMC free article] [PubMed]
- Meyer K, Marquis J, Trüb J, Nlend R, Verp S, Ruepp MD et al (2009) Rescue of a severe mouse model for spinal muscular atrophy by U7 snRNA-mediated splicing modulation. Hum Mol Genet 18:546–555 doi: 10.1093/hmg/ddn382. [DOI] [PubMed]