• Ebog

Muscle proteins

(2019)
Summary: Specialized proteins in muscle cells that are the building blocks of the structures constituting the moving and regulatory machinery of muscles. The moving machinery of muscles comprises myofilaments that are discernible by electron microscopy. These myofilaments are of two kinds, that is, myosin and actin proteins, and their regular arrangement within muscle cells gives the striated pattern to skeletal muscle fibers (Fig. 1). It is recognized that the sliding of the two sets of filaments relative to each other is the molecular basis of muscle contraction. To understand the ultimate mechanism that causes the movement of these filaments relative to each other, it is necessary to consider the features of the individual molecules that make up these filaments. Practically all nonmuscle cells, although lacking the filaments of muscle, contain proteins similar to those found in muscle; these proteins are likely to be involved in cell motility and in determining properties of cell membranes