The core protein of growth plate perlecan binds FGF-18 and alters its mitogenic effect on chondrocytes
- 15 December 2007
- journal article
- Published by Elsevier BV in Archives of Biochemistry and Biophysics
- Vol. 468 (2), 244-251
- https://doi.org/10.1016/j.abb.2007.10.006
Abstract
Fibroblast growth factor-18 (FGF-18) has been shown to regulate the growth plate chondrocyte proliferation, hypertrophy and cartilage vascularization necessary for endochondral ossification. The heparan sulfate proteoglycan perlecan is also critical for growth plate chondrocyte proliferation. FGF-18 null mice exhibit a skeletal dwarfism similar to that of perlecan null mice. Growth plate perlecan contains chondroitin sulfate (CS) and heparan sulfate (HS) chains and FGF-18 is known to bind to heparin and to heparan sulfate from some sources. We used cationic filtration and immunoprecipitation assays to investigate the binding of FGF-18 to perlecan purified from the growth plate and to recombinant perlecan domains expressed in COS-7 cells. FGF-18 bound to perlecan with a Kd of 145 nM. Near saturation, ∼103 molecules of FGF-18 bound per molecule of perlecan. At the lower concentrations used, FGF-18 bound with a Kd of 27.8 nM. This binding was not significantly altered by chondroitinase nor heparitinase digestion of perlecan, but was substantially and significantly reduced by reduction and alkylation of the perlecan core protein. This indicates that the perlecan core protein (and not the CS nor HS chains) is involved in FGF-18 binding. FGF-18 bound equally to full-length perlecan purified from the growth plate and to recombinant domains I–III and III of perlecan. These data indicate that low affinity binding sites for FGF-18 are present in cysteine-rich regions of domain III of perlecan. FGF-18 stimulated 3H-thymidine incorporation in growth plate chondrocyte cultures derived from the lower and upper proliferating zones by 9- and 14-fold, respectively. The addition of perlecan reversed this increased incorporation in the lower proliferating chondrocytes by 74% and in the upper proliferating cells by 37%. These results suggest that perlecan can bind FGF-18 and alter the mitogenic effect of FGF-18 on growth plate chondrocytes.Keywords
This publication has 49 references indexed in Scilit:
- Heparan and chondroitin sulfate on growth plate perlecan mediate binding and delivery of FGF-2 to FGF receptorsMatrix Biology, 2007
- Modulation of FGF-2 binding to chondrocytes from the developing growth plate by perlecanMatrix Biology, 2006
- Changes in perlecan during chondrocyte differentiation in the fetal bovine rib growth plateJournal of Orthopaedic Research, 2006
- Basement membrane proteoglycans: from cellar to ceilingNature Reviews Molecular Cell Biology, 2005
- Increased Intimal Hyperplasia and Smooth Muscle Cell Proliferation in Transgenic Mice With Heparan Sulfate–Deficient PerlecanCirculation Research, 2004
- Fibroblast Growth Factor-binding Protein Is a Novel Partner for Perlecan Protein CoreJournal of Biological Chemistry, 2001
- Localization of Glycosaminoglycan Substitution Sites on Domain V of Mouse PerlecanBiochemical and Biophysical Research Communications, 1999
- Mapping of the binding of platelet‐derived growth factor to distinct domains of the basement membrane proteins BM‐40 and perlecan and distinction from the BM‐40 collagen‐binding epitopeEuropean Journal of Biochemistry, 1998
- Developmental expression of perlecan during murine embryogenesisDevelopmental Dynamics, 1997
- Skeletal overgrowth and deafness in mice lacking fibroblast growth factor receptor 3Nature Genetics, 1996