RESUMEN
The ability to control pre-mRNA splicing with small molecules could facilitate the development of therapeutics or cell-based circuits that control gene function. Myotonic dystrophy type 1 is caused by the dysregulation of alternative pre-mRNA splicing due to sequestration of muscleblind-like 1 protein (MBNL1) by expanded, non-coding r(CUG) repeats (r(CUG)(exp)). Here we report two small molecules that induce or ameliorate alternative splicing dysregulation. A thiophene-containing small molecule (1) inhibits the interaction of MBNL1 with its natural pre-mRNA substrates. Compound (2), a substituted naphthyridine, binds r(CUG)(exp) and displaces MBNL1. Structural models show that 1 binds MBNL1 in the Zn-finger domain and that 2 interacts with UU loops in r(CUG)(exp). This study provides a structural framework for small molecules that target MBNL1 by mimicking r(CUG)(exp) and shows that targeting MBNL1 causes dysregulation of alternative splicing, suggesting that MBNL1 is thus not a suitable therapeutic target for the treatment of myotonic dystrophy type 1.
Asunto(s)
Distrofia Miotónica/tratamiento farmacológico , Distrofia Miotónica/genética , Precursores del ARN/genética , Empalme del ARN/genética , Bibliotecas de Moléculas Pequeñas/uso terapéutico , Animales , Secuencia de Bases , Exones/genética , Fibroblastos/efectos de los fármacos , Fibroblastos/metabolismo , Fibroblastos/patología , Técnicas de Silenciamiento del Gen , Células HEK293 , Células HeLa , Ensayos Analíticos de Alto Rendimiento , Humanos , Ratones , Simulación del Acoplamiento Molecular , Datos de Secuencia Molecular , Plásmidos/metabolismo , Unión Proteica/genética , Biosíntesis de Proteínas/efectos de los fármacos , ARN/metabolismo , Precursores del ARN/metabolismo , Empalme del ARN/efectos de los fármacos , Proteínas de Unión al ARN/genética , Proteínas de Unión al ARN/metabolismo , Receptor de Insulina/genética , Bibliotecas de Moléculas Pequeñas/química , Bibliotecas de Moléculas Pequeñas/farmacologíaRESUMEN
The US National Institute of Neurological Disorders and Stroke convened major stakeholders in June 2012 to discuss how to improve the methodological reporting of animal studies in grant applications and publications. The main workshop recommendation is that at a minimum studies should report on sample-size estimation, whether and how animals were randomized, whether investigators were blind to the treatment, and the handling of data. We recognize that achieving a meaningful improvement in the quality of reporting will require a concerted effort by investigators, reviewers, funding agencies and journal editors. Requiring better reporting of animal studies will raise awareness of the importance of rigorous study design to accelerate scientific progress.