What is the composition of z line?

The Z line (or Z disc) is a key structural component of striated muscle fibers, particularly in skeletal and cardiac muscles. It is primarily composed of proteins such as alpha-actinin, which anchors the actin filaments, and other proteins like nebulin and titin that help maintain the integrity and elasticity of the muscle fibers. The Z line serves as the boundary between adjacent sarcomeres, facilitating muscle contraction by providing a point of attachment for the thin filaments.