Short- and Long-Term Effects of UVA on Arabidopsis Are Mediated by a Novel cGMP Phosphodiesterase (Current Biology)

Isner et al. show that UVA radiation inhibits stomatal opening in Arabidopsis. This requires a reduction in cytosolic cGMP, mediated by a cGMP-activated phosphodiesterase (AtCN-PDE1) that is conserved across the tree of life, except in metazoans, where it has been lost. They also show that UVA increases growth and decreases water use efficiency.