Freeze Fracture of Skeletal Muscle from the Tarantula Spider
نویسنده
چکیده
The structure of the membranes of sarcoplasmic reticulum (SR), tubular (T) system, and sarcolemma has been studied by freeze fracture in leg muscles of the Tarantula spider. Two regions of the sarcoplasmic reticulum can be differentiated by the distribution of particles on the fracture faces: a junctional SR, at the dyads, and a longitudinal SR, elsewhere. The dyads are asymmetric junctions, the disposition of particles in the apposed membranes of SR and T tubules being different from one another and from the regular arrangement of feet in the junctional gap. It is concluded that no channels can be visualized to directly connect SR- and T-system lumina.
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ورودعنوان ژورنال:
- The Journal of Cell Biology
دوره 61 شماره
صفحات -
تاریخ انتشار 1974