Dr Kazunori OKADA, Agro-biotechnology Research Center, University of Tokyo, Japan, invité par T. Heitz
Plants produce a lot of secondary metabolites, also known as “Specialized metabolites”, which often have specific, but sometimes hidden, functions to help plants become more resistant upon environmental stresses. I have been working on the biosynthesis and regulation of terpenoids in rice, specifically diterpenoid phytoalexins, an antimicrobial substance inductively produced in response to pathogen infection. In such response, it has been shown that plant hormone jasmonates has a pivotal role as a signal molecule to turn on the biosynthetic process of diterpenoid phytoalexins. During the study for seeking of JA-mediated transcriptional regulators, we found a bHLH factor, which is early responsive to jasmonates named RERJ1 (Rice Early Responsive to Jasmonate 1) and investigated its molecular function with our expectation for its involvement on the regulation on diterpene phytoalexin production. However, it seemed that RERJ1 was not involved in this process, and thus its biological function has long been unknown. In this talk, I will show our finding regarding the biological function of RERJ1 on volatiles production including monoterpenoid odor upon wound stresses with some inside stories behind the discovery.