Expression Pattern of WWP1 in Muscular Dystrophic and Normal Chickens

The WW domain containing E3 ubiquitin protein ligase 1 (WWP1) is classified into one of ubiquitin ligases which play an important role in ubiquitin-proteasome pathway. Previously, we identified the WWP1 gene as a candidate gene of chicken muscular dystrophy by linkage analysis and sequence comparison. However, the mechanism causing pathological changes and underlaying gene function remains elucidated. In the present study, we analyzed the WWP1 gene expression in various muscles and tissues of normal chickens, and compared with those from muscular dystrophic chickens. Two mRNA isoforms were detected in all tissues examined and revealed almost equal expression level. The WWP1 expression of dystrophic chickens was decreased in almost all skeletal muscles including unaffected muscles. These data indicate that there might not be a causal relationship between the alteration of WWP1 expression level and the severity of muscular dystrophy

The ubiquitin ligase gene (WWP1) is responsible for the chicken muscular dystrophy

AbstractChicken muscular dystrophy with abnormal muscle (AM) has been studied for more than 50 years, but the gene responsible for it remains unclear. Our previous studies narrowed down the AM candidate region to approximately 1Mbp of chicken chromosome 2q containing seven genes. In this study, we performed sequence comparison and gene expression analysis to elucidate the responsible gene. One missense mutation was detected in AM candidate genes, while no remarkable alteration of expression patterns was observed. The mutation was identified in WWP1, detected only in dystrophic chickens within several tetrapods. These results suggested WWP1 is responsible for chicken muscular dystrophy