Iron Regulatory Protein 1 (IRP1) is a key protein that helps maintain iron homeostasis in cells. It regulates the expression of genes involved in iron metabolism by binding to specific RNA sequences called iron-responsive elements (IREs). When iron levels are low, IRP1 stabilizes mRNAs that promote iron uptake and storage. In addition to its role in iron regulation, IRP1 can also function as a cytosolic aconitase, an enzyme involved in the citric acid cycle. This dual function allows IRP1 to respond to cellular iron levels while also participating in energy metabolism, highlighting its importance in cellular health.