Glypican-6 promotes the growth of developing long bones by stimulating Hedgehog signaling

Mariana Capurro; Tomomi Izumikawa; Philippe Suarez; Wen Shi; Marzena Cydzik; Tomoyuki Kaneiwa; Jean Gariepy; Luisa Bonafe; Jorge Filmus

doi:10.1083/jcb.201605119

Glypican-6 promotes the growth of developing long bones by stimulating Hedgehog signaling

J Cell Biol. 2017 Sep 4;216(9):2911-2926. doi: 10.1083/jcb.201605119. Epub 2017 Jul 10.

Authors

Mariana Capurro^{1

2}, Tomomi Izumikawa^{1

2}, Philippe Suarez³, Wen Shi^{1

2}, Marzena Cydzik^{1

2}, Tomoyuki Kaneiwa^{1

2}, Jean Gariepy^{1

2}, Luisa Bonafe³, Jorge Filmus^{4

2}

Affiliations

¹ Sunnybrook Research Institute, University of Toronto, Toronto, Ontario, Canada.
² Department of Medical Biophysics, University of Toronto, Toronto, Ontario, Canada.
³ Center for Molecular Diseases, Lausanne University Hospital, Lausanne, Switzerland.
⁴ Sunnybrook Research Institute, University of Toronto, Toronto, Ontario, Canada [email protected].

Abstract

Autosomal-recessive omodysplasia (OMOD1) is a genetic condition characterized by short stature, shortened limbs, and facial dysmorphism. OMOD1 is caused by loss-of-function mutations of glypican 6 (GPC6). In this study, we show that GPC6-null embryos display most of the abnormalities found in OMOD1 patients and that Hedgehog (Hh) signaling is significantly reduced in the long bones of these embryos. The Hh-stimulatory activity of GPC6 was also observed in cultured cells, where this GPC increased the binding of Hh to Patched 1 (Ptc1). Consistent with this, GPC6 interacts with Hh through its core protein and with Ptc1 through its glycosaminoglycan chains. Hh signaling is triggered at the primary cilium. In the absence of Hh, we observed that GPC6 is localized outside of the cilium but moves into the cilium upon the addition of Hh. We conclude that GPC6 stimulates Hh signaling by binding to Hh and Ptc1 at the cilium and increasing the interaction of the receptor and ligand.

MeSH terms

Animals
Cell Proliferation
Cilia / metabolism
Disease Models, Animal
Femur / embryology
Femur / metabolism*
Genetic Predisposition to Disease
Glycosaminoglycans / metabolism
Glypicans / deficiency
Glypicans / genetics
Glypicans / metabolism*
Growth Disorders / embryology
Growth Disorders / genetics
Growth Disorders / metabolism*
HEK293 Cells
Hedgehog Proteins / genetics
Hedgehog Proteins / metabolism*
Humans
Mice
Mice, Inbred C57BL
Mice, Knockout
NIH 3T3 Cells
Osteochondrodysplasias / congenital*
Osteochondrodysplasias / embryology
Osteochondrodysplasias / genetics
Osteochondrodysplasias / metabolism
Osteogenesis*
Patched-1 Receptor / metabolism
Phenotype
Protein Binding
Protein Interaction Domains and Motifs
Signal Transduction
Tibia / embryology
Tibia / metabolism*
Time Factors
Transfection
Zinc Finger Protein GLI1 / metabolism

Substances

Gli1 protein, mouse
Glycosaminoglycans
Glypicans
Hedgehog Proteins
Patched-1 Receptor
Ptch1 protein, mouse
Shh protein, mouse
Zinc Finger Protein GLI1
glypican 6 protein, mouse
ihh protein, mouse

Supplementary concepts

Omodysplasia type 1

Grants and funding

MOP142344/CIHR/Canada