Does anyone know why skeletal muscle fibers have peripheral nuclei, but the cardiomyocytes not? What are the functional advantages?
Muscle fibers develop from fusion of myoblast that are centronucleated. Then they accumulate myofibrils and the structural organels of the excitation-contraction coupling apparatus. Finally nuclei move to the periphery and stay there in normal myofibers, why one of the sound morphological markers of myopathies is to find internalized or not peripheralized myonuclei. The peripheral location of the nuclei seem thus the result of an active process that "maintain" the sub-sarcolemmal elicoidal diatribution of the myonuclei. Mechanisms and gene products of the machinery that transport the myonuclei at the periphery of the muscle fibers are well known (in particular in some muscle dystrophies) nothing, instead, of the mechanisms of the peripheral localization. It remains also to be recognized the functional advantages of such mechanisms that are not present in the cardiomyocytes
All Answers (4)
I agree that it is still unknown why skeletal muscle has peripheral nuclei whereas this is not the case for cardiac muscle. Maybe skeletal muscle is so much bigger than cardiac muscle that nuclei must be in the periphery so that contraction occurs correctly. zebrafish do not have peripheral nuclei in their skeletal muscle. I would love to know the answer to this question
I suspect that even comparative myologists do not care for such a fundamental properties of MAMMALIAN Skeletal Muscle.
I will organize a Special Issue of the European Journal of Translational Myology to collect information ... Nuclear displacement is a well-known marker of skeletal muscle pathology, but no one care on the basic questions: Why, How fast they move-in, Is the event reversible?
Adivice, please ...
Its interesting. Do you have some information about what is already known? Like machinery or something...
Please