This Adverse Outcome Pathway (AOP) describes the linkage between Chitin synthase 1 inhibition and mortality in arthropods. In order to grow and develop, arthropods need to shed their exoskeleton (or cuticle) periodically and replace it with a new one in a process called molting. Successful molting, and therefore a successful development necessitates stability and integrity of the cuticle to support muscular contractions involved in the shedding of the old cuticle. Arthropods heavily rely on chitin synthesis as chitin is one of the main constituents of the cuticle. The cuticular chitin synthase (CHS-1) is the key enzyme in the biosynthetic pathway and arthropods are therefore especially dependent on its proper function. The present AOP describes the effects of CHS-1 chemical inhibition on the molting process leading to increased mortality in arthropods. Knowledge gaps still exist in the process and this AOP may help guiding assay development for further experimental studies, addressing these gaps. This AOP is referred to as AOP 360 in the Collaborative Adverse Outcome Pathway Wiki (AOP-Wiki).
