[
1982]
Myosin is the central piece in the protein machinery that produces muscle contraction. In this role, the myosin molecule must serve as an energy-transducing enzyme and as the major building block of the thick filament. In differentiated muscle cells, myosin is constantly being synthesized and assembled into thick filaments. Many issues regarding the processes of myosin synthesis and assembly in muscle remain unresolved. Is the synthesis and assembly of myosin coupled? Are additional protein components required for the assembly of myosin into native thick filaments? Do different myosin isoforms play distinct structural or functional roles within thick filaments? The combined approaches of protein biochemistry, immunology, and electron microscopy have proved useful in establishing our present knowledge concerning the roles of myosin within muscle. The nematode Caenorhabditis elegans offers several experimental advantages in addition to these time-honored methods that may provide further insights concerning the process of myosin synthesis and assembly. This animal has an elegantly simple and well-defined development and anatomy of body-wall muscle cells. Genetic analysis has characterized hundreds of specific mutants in over 20 genes affecting the development, structure, and function of body-wall muscle cells. This genetic approach, in combination with biochemical, immunological, and morphological methods, promises to offer significant