The transcriptional response to intracellular iron deficiency in untreated Hampfl/fl;Myh6.Cre+ mice (upregulation of TfR1 mRNA and downregulation of Slc40a1 mRNA relative to Hampfl/fl controls), was absent in iron-treated Hampfl/fl;Myh6.Cre+ mice, consistent with correction of cardiomyocyte iron deficiency (Figure 4D–E). Here, SLC40A1 is linked to nutritional disorder.