First Author | Vest KE | Year | 2017 |
Journal | Hum Mol Genet | Volume | 26 |
Issue | 17 | Pages | 3235-3252 |
PubMed ID | 28575395 | Mgi Jnum | J:243638 |
Mgi Id | MGI:5909337 | Doi | 10.1093/hmg/ddx206 |
Citation | Vest KE, et al. (2017) Novel mouse models of oculopharyngeal muscular dystrophy (OPMD) reveal early onset mitochondrial defects and suggest loss of PABPN1 may contribute to pathology. Hum Mol Genet 26(17):3235-3252 |
abstractText | Oculopharyngeal muscular dystrophy (OPMD) is a late onset disease caused by polyalanine expansion in the poly(A) binding protein nuclear 1 (PABPN1). Several mouse models have been generated to study OPMD; however, most of these models have employed transgenic overexpression of alanine-expanded PABPN1. These models do not recapitulate the OPMD patient genotype and PABPN1 overexpression could confound molecular phenotypes. We have developed a knock-in mouse model of OPMD (Pabpn1+/A17) that contains one alanine-expanded Pabpn1 allele under the control of the native promoter and one wild-type Pabpn1 allele. This mouse is the closest available genocopy of OPMD patients. We show that Pabpn1+/A17 mice have a mild myopathic phenotype in adult and aged animals. We examined early molecular and biochemical phenotypes associated with expressing native levels of A17-PABPN1 and detected shorter poly(A) tails, modest changes in poly(A) signal (PAS) usage, and evidence of mitochondrial damage in these mice. Recent studies have suggested that a loss of PABPN1 function could contribute to muscle pathology in OPMD. To investigate a loss of function model of pathology, we generated a heterozygous Pabpn1 knock-out mouse model (Pabpn1+/Delta). Like the Pabpn1+/A17 mice, Pabpn1+/Delta mice have mild histologic defects, shorter poly(A) tails, and evidence of mitochondrial damage. However, the phenotypes detected in Pabpn1+/Delta mice only partially overlap with those detected in Pabpn1+/A17 mice. These results suggest that loss of PABPN1 function could contribute to but may not completely explain the pathology detected in Pabpn1+/A17 mice. |