Cyanogenesis can act as defence against herbivores and the amount of HCN generated per unit time is crucial in its role as a feeding deterent. Kadow et al. examine linamarase and hydroxynitrile lyase in rubber tree, Hevea brasiliensis, and find up to ten-fold increases in activity that occur within seconds in response to tissue damage. In contrast to genetic and transcriptional regulation, this post-translational activation allows an immediate, local and damage-type-dependent modulation of the cyanogenic response, which plays a decisive role in defence against herbivores and pathogens.
