Molecular Insights into the Biosynthesis of Insect Cuticles

The insect cuticle is a complex extracellular matrix that provides physical support and protection against infection, dehydration, mechanical injury, and stress. Chitin with different degrees of deacetylation and various kinds of cuticle proteins, lipids, and other organic molecules are crucial structural components of the insect cuticle. To meet the demands of development, insects periodically molt to shed their old cuticles and form new ones. Increasing research attention has been focused on the molecular mechanism of cuticle biosynthesis and the intracellular transport and assembly of the structural components. Although the whole picture of how insect cuticle is precisely formed remains elusive, breakthroughs in the last decade have revealed a number of enzymes and protein factors that are involved in the cuticle formation. This review summarizes recent advances in molecular aspects of insect cuticles, with particular emphasis on the roles of proteins, which are also promising targets for pest control and management.