Tropomyosin-1 also known as Tropomyosin α, TPM1 is a member of the tropomyosin family of highly conserved, widely distributed actin-binding proteins involved in the contractile system of striated and smooth muscles and the cytoskeleton of non-muscle cells. Tropomyosin-1 plays a crucial role in muscle contraction and cellular structure by binding to actin filaments, thereby stabilizing their structure and modulating the interaction between actin and myosin. This interaction is vital for muscle contraction and cellular motility, making Tropomyosin-1 key player in both cardiac and skeletal muscle function. Tropomyosin-1 undergoes alternative splicing, resulting in several isoforms expressed in different tissues, including skeletal muscle, smooth muscle, and fibroblasts, which allows for specialized functions in various cell types.