1 Matching Annotations
- May 2023
-
accessmedicine.mhmedical.com accessmedicine.mhmedical.com
-
iron-bearing transferrin interacts with its receptor
- Iron is transported in the blood by the iron-transferrin complex.
- The complex interacts with specific transferrin receptors on the surface of cells that express transferrin receptors, such as developing erythroblast cells.
- The iron-bearing transferrin is internalized via clathrin-coated pits and transported to an acidic endosome.
- Iron is released from the transferrin at the low pH of the endosome.
- Iron is made available for heme synthesis.
- The transferrin-receptor complex is recycled to the surface of the cell.
- The bulk of the transferrin is released back into circulation, and the transferrin receptor re-anchors into the cell membrane.
- Iron in excess of the amount needed for hemoglobin synthesis binds to a storage protein, apoferritin, forming ferritin.
- Senescent red cells are recognized by the cells of the reticuloendothelial system and undergo phagocytosis.
- Hemoglobin is broken down, and the iron is shuttled back to the surface of the RE cell.
- Iron is presented to circulating transferrin via the iron export channel, ferroportin.
- Iron is then available for reutilization for hemoglobin synthesis
-