Hepcidin associated with which molecule?
**Core Concept**
Hepcidin is a key regulator of iron metabolism, acting as a hormone that controls iron levels in the body by binding to and inhibiting the release of iron from cellular stores.
**Why the Correct Answer is Right**
Hepcidin binds to the iron exporter ferroportin, causing its internalization and degradation. This action prevents iron from being released from cells into the bloodstream, thereby reducing iron availability and promoting its sequestration in cells. The hepcidin-ferroportin interaction is a critical mechanism for regulating iron homeostasis and preventing iron overload.
**Why Each Wrong Option is Incorrect**
* **Option A:** This option is incorrect as hepcidin does not bind to transferrin, which is a protein that transports iron in the bloodstream.
* **Option B:** This option is incorrect as hepcidin does not bind to ferritin, which is a protein that stores iron in cells.
* **Option C:** This option is incorrect as hepcidin does not bind to hemosiderin, which is a protein that stores iron in cells.
**Clinical Pearl / High-Yield Fact**
Ferroportin is the only known receptor for hepcidin, and its downregulation or mutation can lead to excessive iron release and iron overload, as seen in hereditary hemochromatosis.
**Correct Answer: C. Ferroportin**