Dystrophin Cleavage and Sarcolemma Detachment are Early Post Mortem Changes on Bass (Dicentrarchus labrax) White Muscle

Abstract

ABSTRACT Using specific dystrophin antibodies directed against a conserved C‐terminal sequence, we demonstrated that dystrophin of fish white muscle was quickly degraded by 50% within 24h and by 100% within 2 days, in parallel with titin cleavage and alpha‐actinin release from Z‐disks. These changes were accompanied by sarcolemma detachment from the myofibers in costameres (the structures containing dystrophin) and Z‐disks weakening. For muscle stored during 2 to 6 mo before thawing, total dystrophin disappearance was observed at 4°C in <8h. Dystrophin may serve as a marker for stored fish to evaluate post mortem changes or detect a thawing‐freezing process.