FOX1 encodes an iron deficiency-induced ferroxidase involved in a high-affinity iron uptake system. Mutagenesis analysis of the FOX1 promoter identified two separate iron-responsive elements, FeRE1 (CACACG) and FeRE2 (CACGCG), between positions –87 and –82 and between positions –65 and –60, respectively, and both are needed for induced FOX1 expression under conditions of iron deficiency.