Pentagone internalises glypicans to fine-tune multiple signalling pathways
Norman M, Vuilleumier R, Springhorn A, Gawlik J, Pyrowolakis G.
eLife 2016;5:e13301
We uncover a new mechanism contributing in shaping gradients of BMP and WNT signalling in Drosophila. We show that the secreted protein Pentagone induces the endocytosis of glypicans, GPI-anchored heparan sulfate proteoglycans that bind ligands and act as co-receptors. By titrating the levels of membrane-exposed glypicans, Pent adjusts the "stickiness" of the extracellular matrix for BMPs and WNTs and enables proper establishment of the signalling gradients.
