Albertine Donker

Chapter 2 54 Table 1. Continued Compartment Iron content (mg) Key iron-containing protein(s) Function of iron- containing protein(s) Bone 62 (Continued) ? Differentiation from mesenchymal stem cells to osteoblasts Proteins involved in mitochondrial activity (see below: cellular level) Osteoclast activity (rich of mitochondria) Thyroid gland 190-192,208 ? Heme-containing enzyme thyroid peroxidase (TPO) Catalyzes iodide oxidation, thyroglobulin iodination and iodothyronine coupling Deiodinases Tissue conversion of T4 to T3 ? TSH secretion Cellular level 1,201* Heme-containing enzymes 1,107,109 150 Cytochrome P450 monooxygenase, cytochrome C Mitochondrial electron transport chain, drug metabolism NADPH oxygenase, myeloperoxidase Antimicrobial oxidative burst in neutrophils Iron-sulfur enzymes 209 Iron Responsive Protein-1 (IRP-1) Cellular iron homeostasis Ferrochelatase Last step of heme biosynthesis Complex I-III, tricarboxylic acid (TCA) cycle Mitochondrial electron transport chain DNA polymerase, DNA helicase DNA replication and repair Other iron containing proteins, non-heme, non iron-sulfur 210 Lipoxygenase Metabolisation of polyunsaturated fatty acids Parenchymal iron (liver) and reticuloendothelial iron (liver, spleen) 1,201,202,204 1000 Ferritin, hemosiderin Iron storage Total 4000-5000