title: Sonic hedgehog processing and release are regulated by glypican heparan sulfate proteoglycans.
abstract: All Hedgehog morphogens are released from producing cells, despite being synthesized as N- and C-terminally lipidated molecules, a modification that firmly tethers them to the cell membrane. We have previously shown that proteolytic removal of both lipidated peptides, called shedding, releases bioactive Sonic hedgehog (Shh) morphogens from the surface of transfected Bosc23 cells. Using in vivo knockdown together with in vitro cell culture studies, we now show that glypican heparan sulfate proteoglycans regulate this process, through their heparan sulfate chains, in a cell autonomous manner. Heparan sulfate specifically modifies Shh processing at the cell surface, and purified glycosaminoglycans enhance the proteolytic removal of N- and C-terminal Shh peptides under cell-free conditions. The most likely explanation for these observations is direct Shh processing in the extracellular compartment, suggesting that heparan sulfate acts as a scaffold or activator for Shh ligands and the factors required for their turnover. We also show that purified heparan sulfate isolated from specific cell types and tissues mediates the release of bioactive Shh from pancreatic cancer cells, revealing a previously unknown regulatory role for these versatile molecules in a pathological context.
authors.affiliation: Institute for Physiological Chemistry and Pathobiochemistry, University of Münster, 48149 Münster, Germany.
authors.forename: Corinna
authors.initials: C
authors.lastname: Ortmann
authors.affiliation: Institute for Physiological Chemistry and Pathobiochemistry, University of Münster, 48149 Münster, Germany.
authors.forename: Ute
authors.initials: U
authors.lastname: Pickhinke
authors.affiliation: Institute for Physiological Chemistry and Pathobiochemistry, University of Münster, 48149 Münster, Germany.
authors.forename: Sebastian
authors.initials: S
authors.lastname: Exner
authors.affiliation: Institute for Physiological Chemistry and Pathobiochemistry, University of Münster, 48149 Münster, Germany.
authors.forename: Stefanie
authors.initials: S
authors.lastname: Ohlig
authors.affiliation: Department of Cellular and Molecular Medicine, University of California San Diego, La Jolla, CA 92093, USA.
authors.forename: Roger
authors.initials: R
authors.lastname: Lawrence
authors.affiliation: Institute for Physiological Chemistry and Pathobiochemistry, University of Münster, 48149 Münster, Germany.
authors.forename: Hamodah
authors.initials: H
authors.lastname: Jboor
authors.affiliation: Institute for Physiological Chemistry and Pathobiochemistry, University of Münster, 48149 Münster, Germany Cells-in-Motion Cluster of Excellence (EXC1003-CiM), University of Münster, 48149 Münster, Germany.
authors.forename: Rita
authors.initials: R
authors.lastname: Dreier
authors.affiliation: Institute for Physiological Chemistry and Pathobiochemistry, University of Münster, 48149 Münster, Germany Cells-in-Motion Cluster of Excellence (EXC1003-CiM), University of Münster, 48149 Münster, Germany kgrobe@uni-muenster.de.
authors.forename: Kay
authors.initials: K
authors.lastname: Grobe
mesh_terms: D000818:Animals; D015153:Blotting, Western; D019521:Body Patterning; D002462:Cell Membrane / Q000378:metabolism; D002478:Cells, Cultured; D029721:Drosophila Proteins / Q000235:genetics / Q000378:metabolism*; D004331:Drosophila melanogaster / Q000235:genetics / Q000254:growth & development / Q000378:metabolism*; D053673:Glypicans / Q000378:metabolism*; D053823:Hedgehog Proteins / Q000235:genetics / Q000378:metabolism*; D006497:Heparan Sulfate / Q000378:metabolism; D006801:Humans; D051379:Mice; D010190:Pancreatic Neoplasms / Q000235:genetics / Q000378:metabolism*; D011499:Protein Processing, Post-Translational; D059748:Proteolysis; D012333:RNA, Messenger / Q000235:genetics; D060888:Real-Time Polymerase Chain Reaction; D020133:Reverse Transcriptase Polymerase Chain Reaction
chemical_list: D029721:Drosophila Proteins; D053673:Glypicans; D053823:Hedgehog Proteins; D006497:Heparan Sulfate; D012333:RNA, Messenger
keywords: Glycosaminoglycan; Glypican; Heparan sulfate; Shedding; Sonic hedgehog