Disarming the defenses: Insect detoxification of plant defense-related specialized metabolites
Kristina Kshatriya, Jonathan Gershenzon
Abstract
The ability of certain insects to feed on plants containing toxic specialized metabolites may be attributed to detoxification enzymes. Representatives of a few large families of detoxification enzymes are widespread in insect herbivores acting to functionalize toxins and conjugate them with polar substituents to decrease toxicity, increase water solubility and enhance excretion. Insects have also developed specific enzymes for coping with toxins that are activated upon plant damage. Another source of detoxification potential in insects lies in their microbiomes, which are being increasingly recognized for their role in processing plant toxins. The evolution of insect detoxification systems to resist toxic specialized metabolites in plants may in turn have selected for the great diversity of such metabolites found in nature. • Insects feed on many plants producing toxic specialized metabolites. • Insect genomes encode large families of detoxification enzymes. • Detoxification enzymes act to increase water solubility and enhance excretion. • Insects also detoxify activated or two-component defenses formed on plant damage. • Symbionts from the gut microbiome may also be involved in insect detoxification.