A molecular link between photoreceptors and jasmonates (Nature Plants)

Plants balance their efforts on growth and defense depending on the situation. Competitive conditions signaled by the low ratios of red (R) to far-red (FR) light suppress defense responses mediated by the plant hormone jasmonate (JA), presumably for allocating more resources to promote plant growth. Fernández-Milmanda et al. identified the sulfotransferase ST2a as a missing link between photoreceptor-mediated light signaling and JA signaling. The authors found that low R:FR conditions induce ST2a in a manner dependent on the phyB-PIF pathway, a central regulator of light responses. ST2a catalyzes the sulfation of JA compounds to reduce the accumulation of bioactive JA conjugates. They demonstrated that ST2a is required for light-dependent signaling to mitigate JA responses and defense against pathogens. This study revealed a molecular mechanism by which light quality affects the homeostasis of JA compounds rewiring plant responses to the environment. (Summary by Tatsuya Nobori) Nature Plants 10.1038/s41477-020-0604-8