The FGF23 gene provides instructions for making a protein called fibroblast growth factor 23, which is produced in bone cells. This protein helps regulate phosphate levels within the body. Among its many functions, phosphate plays a critical role in the formation and growth of bones during childhood and helps maintain bone strength in adults.
Fibroblast growth factor 23 works in the kidneys to keep the body’s phosphate levels in balance. The kidneys normally release excess phosphate in the urine, and they reabsorb this mineral into the bloodstream when more is needed. Fibroblast growth factor 23 acts as a signal that tells the kidneys to stop reabsorbing phosphate into the bloodstream.
In order for fibroblast growth factor 23 to function, sugar molecules must attach to the protein through a process called glycosylation. This allows fibroblast growth factor 23 to move out of the bone cell and protects it from being broken down. Once outside the cell, fibroblast growth factor 23 must bind to a receptor protein that spans the membrane of kidney cells. Binding to this receptor triggers a signaling pathway that stops phosphate reabsorption by the kidneys. When more phosphate is needed, fibroblast growth factor 23 is cut (cleaved) at a certain site, which turns off (inactivates) the protein. This helps regulate the amount of active fibroblast growth factor 23 that is circulating in the bloodstream.
Related Genetics Topics
- Hyperphosphatemic familial tumoral calcinosis — MedlinePlus Genetics
- Kidney stones — MedlinePlus Genetics
Identifiers
- NCBI Gene: 8074
- OMIM: 605380
Source: MedlinePlus Genetics, U.S. National Library of Medicine.
