Circadian rhythms regulate a wide variety of developmental and metabolic processes resulting in enhanced fitness. In this study, a link is made between plant immune responses and the circadian clock. Plant defence against a fungal pathogen which causes downy mildew disease in Arabidopsis is studied, and it is shown that a novel set of defence genes are regulated by the circadian regulator CIRCADIAN CLOCK-ASSOCIATED 1 (CCA1). The mechanism allows plants to 'anticipate' infection at dawn when the pathogen normally disperses its spores. Such a cross-talk mechanism reveals an important strategy for plants to time immune responses against pathogens.
- Wei Wang
- Jinyoung Yang Barnaby
- Xinnian Dong