The missing link in the ‘safe signal’ of plants

Dutch biologists have discovered the missing link in the ‘safe signal’ of plants. Although a lot of information was already known about jasmonic acid and it effects, the so called ‘safe signal’ was quite a mystery.

Plants produce jasmonic acid in a situation where it is threatened by a fungus or insects, directly enabling the defense system of the plant. The jasmonic acid counters the infection, while also halting the growth of the plant. After the attack, the level of jasmonic acid drops; a process which was left unexplained, until now.

The biologists discovered that the ‘safe signal’ are four related enzyme being released simultaneously, all starting a chemical process where an oxygen atom is linked to the jasmonic acid. This in turn creates an inactive variation of the hormone, namely the inactive 12-hydroxy-jasmonic acid. The inactive variation, unlike the active jasmonic acid, does not enable the defense system.

By understanding this process, biologists will be able to manipulate the process, thereby providing the possibility to increase the resistance of plants against fungus and insects.

Phenotyping plays a key role in the documentations, analyzes and identification of these discoveries.

(Image: left a ‘normal plant’ with infection, right a plant which is manipulated by biologists)

References:
https://www.uu.nl/nieuws/biologen-vinden-missende-schakel-voor-het-sein-veilig-in-planten
Caarls, L., Elberse, J., Awwanah, M., Ludwig, N. R., Vries, M. d., Zeilmaker, T., . . . Ackerveken, G. V. (2017, May 28). Arabidopsis JASMONATE-INDUCED OXYGENASES down-regulate plant immunity by hydroxylation and inactivation of the hormone jasmonic acid. Retrieved from bioRvix: http://biorxiv.org/content/biorxiv/early/2017/05/28/102103.full.pdf