Current Molecular Biology Reports

, Volume 5, Issue 1, pp 18–25 | Cite as

FGF23 Synthesis and Activity

  • Megan L. Noonan
  • Kenneth E. WhiteEmail author
Molecular Control of Phosphorus Homeostasis (B van der Eerden, Section Editor)
Part of the following topical collections:
  1. Topical Collection on Molecular Control of Phosphorus Homeostasis


Purpose of Review

The phosphaturic hormone FGF23 is produced primarily in osteoblasts/osteocytes and is known to respond to increases in serum phosphate and 1,25(OH)2 vitamin D (1,25D). Novel regulators of FGF23 were recently identified and may help explain the pathophysiologies of several diseases. This review will focus on recent studies examining the synthesis and actions of FGF23.

Recent Findings

The synthesis of FGF23 in response to 1,25D is similar to other steroid hormone targets, but the cellular responses to phosphate remain largely unknown. The activity of intracellular processing genes control FGF23 glycosylation and phosphorylation, providing critical functions in determining the serum levels of bioactive FGF23. The actions of FGF23 largely occur through its co-receptor αKlotho (KL) under normal circumstances, but FGF23 has KL-independent activity during situations of high concentrations.


Recent work regarding FGF23 synthesis and bioactivity, as well as considerations for diseases of altered phosphate balance, will be reviewed.


Fibroblast growth factor-23 FGF23 PTH Vitamin D Phosphate Klotho Rickets Osteomalacia GALNT3 FAM20C, PSC3 Furin 



KEW receives royalties for licensing the FGF23 gene to Kyowa Hakko Kirin, Ltd.; the authors would like to acknowledge support by NIH grants DK112958, DK095784, and AR059278 (KEW), and T32-HL007910 (MLN).

Compliance with Ethical Standards

Conflict of Interest

Megan L. Noonan and Kenneth E. White each declare no potential conflicts of interest.

Human and Animal Rights and Informed Consent

This article does not contain any studies with human or animal subjects performed by any of the authors.


Papers of particular interest, published recently, have been highlighted as:•• Of major importance

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© Springer Nature Switzerland AG 2019

Authors and Affiliations

  1. 1.Department of Medical & Molecular GeneticsIndiana University School of MedicineIndianapolisUSA

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