Figure A2.

Analysis of iron balance and immune-related genes. (A): Protein–protein interaction analysis. The interactions among hepcidin (HAMP), FPN1, TFR1, FTN, IL-1β, IL8, TNF-α, and SOCS3 proteins were analyzed using a human model. The spheres and lines represent proteins and interactions. The light blue, pink, olive, and black lines represent the analysis from the database, experimental data, text mining data, and co-expression data, respectively. (B): Model diagram of iron balance mechanism. Transferrin (TF) carries Fe³⁺ and binds to TFR1. In this process, Fe³⁺ is changed to Fe²⁺ by other accessory proteins, and Fe²⁺ is transported into cells by TFR1. FTN can store excess Fe²⁺ in the cells. Fe²⁺ is exported outside of the cells via FPN1. In this process, Fe²⁺ is changed to Fe³⁺ by other accessory proteins. Fe³⁺ is then carried by TF and transported by blood to the site where it is stored or needed. HAMP binds to FPN1, internalizes, and degrades FPN1 to block iron output.