Conferring High IAA Productivity on Low-IAA-Producing Organisms with PonAAS2, an Aromatic Aldehyde Synthase of a Galling Sawfly, and Identification of Its Inhibitor

Gall-inducing insects often contain high concentrations of phytohormones, such as auxin and cytokinin, which are suggested to be involved in gall induction, but no conclusive evidence has yet been obtained. There two possible approaches investigating the importance phytohormones induction: demonstrating either that phytohormone productivity can induce gall-inducing ability non-gall-inducing or is inhibited when galling suppressed. In this study, we show overexpression PonAAS2, encodes an aromatic aldehyde synthase (AAS) responsible for rate-limiting step indoleacetic acid (IAA) biosynthesis a sawfly (Pontania sp.) contains levels endogenous IAA, conferred IAA on Caenorhabditis elegans, model system. This result strongly suggests PonAAS2 also confer low-IAA-producing insects. We successfully identified inhibitor chemical library. highly selective showed stronger inhibitory activity against AAS than amino decarboxylase, belongs same superfamily AAS. confirm clearly high-IAA-producing C. elegans engineered here.