Protein aggregation in congenital myopathies

Abstract

Protein aggregation in congenital myopathies may be encountered among different myofibrillar myopathies such as granulofilamentous myopathy, cytoplasmic body myopathy, or spheroid body myopathy, which are designated as αB crystallinopathy, desminopathy, and myotilinopathy, respectively, according to the respective mutant proteins. Caps in cap disease and reducing bodies in reducing body myopathy were disclosed to contain numerous proteins. The multitude of diverse proteins aggregating within muscle fibers suggests impaired extralysosomal degradation of proteins, a disturbance of catabolism. The lack of different proteins accruing, but the mutant ones at an early age of affected patients in actin filament aggregating myopathy (AFAM) and hyaline body myopathy (HBM), suggests defects in maturation of sarcomeres and failure to integrate the possible mutant proteins, sarcomeric actin and heavy chain myosin in AFAM and HBM, a disturbance of anabolic metabolism.