1 Montreal Neurological Institute and Hospital, McGill University, Montreal, QC H3A2B4, Canada.
2 Electrical & Computer Engineering Department, Concordia University, 1455 boulevard de Maisonneuve O., Montreal, QC H3G 1M8, Canada; Biology Department, Concordia University, 7141 rue Sherbrooke O., Montreal, QC H4B 1R6, Canada.
3 INRS-Institut Armand-Frappier, 531 boulevard des Prairies, Laval, QC H7V 1B7, Canada.
4 Department of Neuroscience, Center for Neurobiology, Temple University School of Medicine, 3500 N. Broad Street, Philadelphia, PA 19140, USA.
5 CHUM Research Center, Montreal, QC H2X 3H8, Canada; Department of Neuroscience, University of Montreal, Montreal, QC H3T 1J4, Canada.
6 INSERM, Laboratory of Neuronal Cell Biology and Pathology, Center for Psychiatry and Neuroscience UMR 894 and University of Paris Descartes, Equipe d'accueil 4059, 75014 Paris, France.
7 Biology Department, Concordia University, 7141 rue Sherbrooke O., Montreal, QC H4B 1R6, Canada.
8 Montreal Neurological Institute and Hospital, McGill University, Montreal, QC H3A2B4, Canada; Department of Neurology and Neurosurgery, McGill University, Montreal, QC, Canada. Electronic address: guy.rouleau@mcgill.ca.

RNA-Based Therapy Utilizing Oculopharyngeal Muscular Dystrophy Transcript Knockdown and Replacement.

Mol Ther Nucleic Acids. 2019 Apr 15;15:12-25

Authors: Abu-Baker A, Kharma N, Perreault J, Grant A, Shekarabi M, Maios C, Dona M, Neri C, Dion PA, Parker A, Varin L, Rouleau GA

Abstract

Oculopharyngeal muscular dystrophy (OPMD) is caused by a small expansion of a short polyalanine (polyAla) tract in the poly(A)-binding protein nuclear 1 protein (PABPN1). Despite the monogenic nature of OPMD, no treatment is currently available. Here we report an RNA replacement strategy that has therapeutic potential in cell and C. elegans OPMD models. We develop selective microRNAs (miRNAs) against PABPN1, and we report that miRNAs and our previously developed hammerhead ribozymes (hhRzs) are capable of reducing the expression of both the mRNA and protein levels of PABPN1 by as much as 90%. Since OPMD derives from a very small expansion of GCG within the polyAla tract, our hhRz and miRNA molecules cannot distinguish between the wild-type and mutant mRNAs of PABPN1. Therefore, we designed an optimized-codon wild-type PABPN1 (opt-PABPN1) that is resistant to cleavage by hhRzs and miRNAs. Co-expression of opt-PABPN1 with either our hhRzs or miRNAs restored the level of PABPN1, concomitantly with a reduction in expanded PABPN1-associated cell death in a stable C2C12 OPMD model. Interestingly, knockdown of the PABPN1 by selective hhRzs in the C. elegans OPMD model significantly improved the motility of the PABPN1-13Ala worms. Taken together, RNA replacement therapy represents an exciting approach for OPMD treatment.

PMID: 30831428 [PubMed]