Iron-sulphur (Fe-S) proteins are crucial to life-sustaining processes such as respiration, photosynthesis and nitrogen fixation. These metalloproteins contain ancient but versatile co-factors, called Fe-S clusters, consisting of iron and acid-labile sulphide. In plant cells, evolutionary conserved Fe-S cluster assembly pathways have been localized to the mitochondria, plastids and the cytosol. Whereas the last decade was dedicated to the characterization of individual components, we still do not know how the pathways interact in plants, although there is evidence for such interaction. In particular, deletion of the mitochondrial ABC transporter AtATM3 is known to impair plastid functions. In this proposal, I will address the relationship between the compartmentalized Fe-S cluster assembly machineries in plants. I will use both reverse and forward genetic approaches in the model plant Arabidopsis thaliana to obtain a map of the interactions between Fe-S assembly pathways. First, using selected mutants, I will assess whether impairment of one specific pathway affects the assembly of Fe-S proteins in other cell compartments. Second, to investigate how AtATM3 is involved in chloroplast functions and get clues about its substrate, I will search for mutations that suppress the chlorotic phenotype of atm3 mutant. Possible interactions with Fe homeostasis will also be investigated. This fellowship will introduce me to a novel model organism and new techniques, within a very successful Anglo-Saxon education model (Cambridge) from which I hope to take elements for my future research/teaching career.