Sulfation switch in the shade.
In a recent News & Views article, Claus Wasternack highlights a study led by the Ballaré Lab from Argentinia (Fernandez-Milmanda et al.) His article was published alongside the study in the March issue of Nature Plants. Wasternack commends the thorough work by Fernandez-Milmanda et al. who show that an Arabidopsis sulfotransferase (ST2a) links photoreceptors and hormone signaling. The authors provide evidence that ST2a converts active forms of jasmonate (JA) into inactive HSO4-JA. Initially, they had identified ST2a as a gene that is upregulated under conditions that switch off the phytochrome B pathway. Such conditions occur, e.g., under shade from neighboring plants. Inactive phytochrome B then triggers the typical shade avoidance responses in plants. As ST2a attenuates JA signaling, shade avoidance seems to be given priority over JA-dependent defense responses. Wasternack concludes that Fernandez-Milmanda et al. succeeded in demonstrating for the first time that a specific metabolic conversion in the homeostasis of JA compounds depends on light quality.
Wasternack, C. Sulfation switch in the shade. Nat Plants 6, 186–187 (2020). https://doi.org/10.1038/s41477-020-0620-8
