Crosstalk between iron homeostasis and immunity in Arabidopsis thaliana – Immuniron

The ability to integrate multiple environmental parameters is key for plant survival. On the one hand, iron (Fe) is an essential micronutrient for all living organisms. However, low Fe bioavailability in soils often limits plant growth. On the other hand, plants are constantly challenged by pathogens and have developed an immune system to resist infections. Perturbation of Fe homeostasis is a major strategy in host-pathogen interactions. However, direct molecular connections between the Fe homeostasis network and the plant immune system have not yet been established. Based on the recent identification of a mutation in NRG1, a receptor of the plant immune system, in a screen for tolerance to Fe deficiency, the project will explore the cross-talk between the immune system and the Fe homeostasis network using a combination of molecular genetics, biochemistry, ionomics, transcriptomics and metabolomics. The response of mutants affected in NRG1 and other components of the immune system to Fe deficiency will be characterized. Reciprocally, the response of mutants affecting regulators of Fe homeostasis to pathogen challenge will be studied. NRG1 function and its genetic and physical interactions with components of the Fe homeostasis network will be analyzed. This is expected to shed light on the molecular connections between immunity and Fe nutrition. The partnership involving teams working on metal homeostasis, plant-pathogen interaction and signaling provides all the necessary expertise to successfully implement the project. The outcome of the project should open new perspectives for developing wide-spectrum plant protection against pathogens, while improving concomitantly plant tolerance to Fe deficiency.