Description
Oculopharyngeal muscular dystrophy (OPMD) is an adult-onset syndrome characterized by progressive degeneration of specific muscles. OPMD is caused by short GCN repeat expansions within the gene encoding the nuclear poly(A)-binding protein 1 (PABPN1) that extend an N-terminal polyalanine tract in the protein. Mutant PABPN1 aggregates as nuclear inclusions in OMPD patient muscles. We have used the transgenic mouse A17.1 OPMD model that recapitulates the features of the human disorder: progressive muscle weakness, atrophy and formation of PABPN1 nuclear inclusions. Wild-type human PABPN1 contains a stretch of 10 alanines following the initial methionine, which is expanded to 1118 alanines in OPMD patients. Transgenic A17.1 mouse overexpress an 17 alanine expanded PABPN1 under the control of the HSA promoter. To evaluate a gene therapy approach based on AAV delivery of a suppress and replace strategy in OPMD we performed a transcriptomic analysis in treated muscles 18 weeks after injection. Using microarrays, tibialis anterior gene expression was compared between control muscles (FvB), OPMD muscles (A17), AAV-shRNA3x treated muscles (A17 shRNA3X), AAVoptPABPN1 treated muscles (A17 optPABPN1), and AAV-shRNA3x+AAV-optPABPN1 treated muscles (A17 dual).