On the Significance of Amino Acids in Insects.

While there are many amino acids in nature, all biological proteins are made of the 20 standard amino acids, which occur in virtually all organisms, including viruses. Here, we move beyond proteins to consider the broader biological significance of amino acids in insects. Some amino acids, particularly glycine, act in insect mating systems. We note that insects have biological requirements for essential amino acids, compounds that are required by many species, but must be acquired by consumption or donated by microbiome components. Dietary amino acid requirements differ among insect groups and species. Some insect species rely on tasting and recalling amino acid tastes in their natural foraging areas. An unknown number of microbiome components provide essential amino acids to their hosts. Together, sensory detection, transport systems, and microbial provisioning position amino acids as multifunctional regulators that connect molecular physiology to behavior and ecology. We conclude by highlighting research priorities-mechanistic studies of transport and sensing, life-stage comparative analyses, and integrative metabolomic approaches-to resolve how amino acids shape insect fitness and to translate these insights for pollinator health, pest management, and edible-insect nutrition.