Heparan sulfate proteoglycans (HSPGs) are important mediators of extracellular signaling by Wnt, Fgf, and hedgehog proteins. Dhoot et al. identify a member of a family of conserved sulfatases, QSulf1, that is responsive to Sonic hedgehog (Shh) signaling in the somite and neural tube. However, QSulf1 does not function directly in the Shh signaling pathway. Instead, HSPG mediates Wnt signaling during avian myogenesis. This work connects HSPGs to signaling events in cell fate determination and identifies a sulfatase enzyme as a signal modulator.
G. K. Dhoot, M. K. Gustafsson, X. Ai, W. Sun, D. M. Standiford, C. P. Emerson Jr., Regulation of Wnt signaling and embryo patterning by an extracellular sulfatase. Science 293, 1663-1666 (2001). [Abstract] [Full Text]