Iron (Fe) is an essential micronutrient for plant productivity and plays a major role during plant growth and development. It is a cofactor for numerous reactions involving electron transfer/oxidation-reduction such as photosynthesis, respiration, nitrogen assimilation etc. Iron homeostasis is tightly regulated in order to avoid deficiency or excess that could be detrimental to the plant. The regulation of the plant response to fluctuations in Fe availability has been extensively studied in many species, highlighting the importance of the transcriptional regulation in this process. In this context, we aim to further characterize the molecular mechanisms that control iron homeostasis in plants, focusing on three main transcription factors URI/ BHLH121, ILR3/BHLH105 and PYE in the model plant Arabidopsis thaliana (non-grass species) and comparing the degree of conservation of this regulatory network in a grass species, Brachypodium distachyon since both type of plants use similar but different strategies to maintain the homeostasis of this micronutrient.