title: The Making and Breaking of Strigolactones

speaker: Prof. Stefan T. Arold

KAUST Center of Excellence for Smart Health, Biological and Environmental Science and Engineering Division, King Abdullah University of Science and Technology (KAUST), Kingdom of Saudi Arabia

Plants use an impressive array of phytohormones to regulate their germination, architecture, and metabolism. To control the action of these phytohormones, plants have developed mechanisms to write, read, and erase these molecules in response to exogenous and endogenous signals.

I will discuss our structural, biochemical, and in planta investigations aimed at uncovering the molecular basis for the controlled production, sensing, and breakdown of strigolactones. Strigolactones are important plant hormones that regulate shoot architecture and stress responses, and act as signals that attract symbiotic fungi. However, root-parasitic Striga plants also sense strigolactones, using them as a trigger for germination in the presence of a host.

Our work has elucidated strigolactone regulation in host plants, their perception in Striga, and fortuitously identified a Striga-specific inhibitor. Based on our findings, I propose the concept of “metabolite ensemble inhibition” as a feedback regulation mechanism.