How does the circadian clock regulate disease resistance?

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This project investigates how a plant's circadian clock (molecular clock) altersits susceptibility to infection at different times of the day. It is an excitingopportunity to work in a new field, learn a range of modern experimental andcomputational skills and join an active, enthusiastic research group. Theresearch will involve genetics, molecular biology, proteomics, high-throughputyeast-2-hybrid, transcriptomics, pathogen infection assays, genomics, geneediting and computational biology.Almost all living organisms ranging from cyanobacteria to plants and animalspossess a circadian clock. The circadian clock generates an ~24 h rhythm that isset by daily cycles of light and temperature. This enables organisms toanticipate regular daily events such as dawn and dusk. For plants, which cannotmove, the circadian clock is particularly important to synchronise itsmetabolism with the environment. Recently it was discovered that the clockalso impacts plant immunity; plants inoculated at different times of the dayshow differing susceptibility to pathogens. We demonstrated that Arabidopsisplants showed greater resistance to Botrytis cinerea, a fungal pathogen, afterinoculation at dawn compared to inoculation during the night (Ingle et al. 2015Plant Journal). The difference in susceptibility when the plants are inoculated atdawn or night is driven by the plant circadian clock.The plant immune response involves significant changes in gene expressionregulated by transcription factors within a regulatory network. Afterinoculation at dawn this defence network is activated faster leading to moreeffective resistance against the pathogen. Incredibly a four-hour difference inactivation of the defence response leads to a dramatic difference in diseaseprogression. Timing is everything! We have found that a single protein in ahormone (jasmonic acid) signaling pathway controls the change in diseasesusceptibility during the day. This protein, JAZ6, works by targetingtranscription factors.We now want to ask how does the clock via JAZ6 control disease resistance?How broad is JAZ6-dependent disease resistance? What transcription factors inthe regulatory network does JAZ6 target? How do changes in the defencenetwork cause increased disease resistance? What is the timing of JAZ6activity?Critically we want to investigate whether we can alter JAZ6 in crop plants toactivate the defence network faster and enhance disease resistance. JAZ6orthologues are present in Brassica, lettuce and tomato (all crops infected by B.cinerea) and we will use gene editing to test whether JAZ6 is a clock-immunityregulator in these crops.