Structural analysis of muscle development: transverse tubules, sarcoplasmic reticulum, and the triad.
Increased interest in the mechanism of excitation-contraction (E-C) coupling over the last few years has been accompanied by numerous investigations into the development of the underlying cellular structures. Areas of particular interest include: (1) the compartmentalization and specialization of an external and an internal membrane system, the T-tubules, and the sarcoplasmic reticulum, respectively; (2) interactions between the membrane proteins of both systems upon the formation of a junction, the triad; and (3) membrane-cytoskeletal interactions leading to the orderly arrangement of the triads with respect to the myofibrils. Structural studies using newly available specific molecular probes and a variety of in vivo and in vitro model systems have provided new insights into the cellular and molecular mechanisms involved in the development of the E-C coupling apparatus in skeletal muscle.
Flucher
B E
BE
Laboratory of Neurobiology, NINDS, National Institutes of Health, Bethesda, Maryland 20892.
D000818:Animals; D009119:Muscle Contraction; D009132:Muscles / Q000196:embryology* / Q000648:ultrastructure; D015388:Organelles / Q000648:ultrastructure; D051381:Rats; D012519:Sarcoplasmic Reticulum / Q000648:ultrastructure*