Format

Send to

Choose Destination
Nature. 2018 Jan 25;553(7689):461-466. doi: 10.1038/nature25451. Epub 2018 Jan 17.

α-Klotho is a non-enzymatic molecular scaffold for FGF23 hormone signalling.

Author information

1
Chemical Biology Research Center, School of Pharmaceutical Sciences, Wenzhou Medical University, Wenzhou, Zhejiang 325035, China.
2
Department of Biochemistry & Molecular Pharmacology, New York University School of Medicine, New York, New York 10016, USA.
3
New York Structural Biology Center, New York, New York 10027, USA.
4
Departments of Internal Medicine and Physiology, and Charles and Jane Pak Center of Mineral Metabolism and Clinical Research, University of Texas Southwestern Medical Center, Dallas, Texas 75390, USA.

Abstract

The ageing suppressor α-klotho binds to the fibroblast growth factor receptor (FGFR). This commits FGFR to respond to FGF23, a key hormone in the regulation of mineral ion and vitamin D homeostasis. The role and mechanism of this co-receptor are unknown. Here we present the atomic structure of a 1:1:1 ternary complex that consists of the shed extracellular domain of α-klotho, the FGFR1c ligand-binding domain, and FGF23. In this complex, α-klotho simultaneously tethers FGFR1c by its D3 domain and FGF23 by its C-terminal tail, thus implementing FGF23-FGFR1c proximity and conferring stability. Dimerization of the stabilized ternary complexes and receptor activation remain dependent on the binding of heparan sulfate, a mandatory cofactor of paracrine FGF signalling. The structure of α-klotho is incompatible with its purported glycosidase activity. Thus, shed α-klotho functions as an on-demand non-enzymatic scaffold protein that promotes FGF23 signalling.

PMID:
29342138
PMCID:
PMC6007875
DOI:
10.1038/nature25451
[Indexed for MEDLINE]
Free PMC Article

Supplemental Content

Full text links

Icon for Nature Publishing Group Icon for PubMed Central
Loading ...
Support Center