Fine-tuning striated muscle performance: conserved sarcomere-level mechanisms across insect and vertebrate systems.

Striated muscles exhibit remarkable structural and functional specialization that enables precise control of force production, contractile kinetics, and energetic efficiency. Although vertebrate skeletal and cardiac muscles have been extensively studied, comparative analyses across animal phyla reveal that many molecular and biophysical principles governing muscle performance are deeply conserved. Insects, in particular, possess highly differentiated muscle types that provide powerful systems for dissecting the regulation of contraction, elasticity, and force generation at the level of the sarcomere. In this review, we integrate insights from insect and vertebrate muscles to highlight conserved and divergent features of sarcomere organization and myofilament composition. We focus on major contractile and regulatory proteins, including actin, myosin, troponin, tropomyosin, and elastic proteins, emphasizing how isoform diversity fine-tunes muscle function. We discuss the biomedical relevance of invertebrate models for understanding muscle disease mechanisms, including congenital myopathies, sarcomeric protein-associated disorders, and muscular dystrophies. Finally, we examine how principles uncovered in insect muscles inform vertebrate cardiac physiology and skeletal muscle aging, positioning insect systems as complementary discovery platforms for advancing muscle biology.