Sulf1 and Sulf2 are two heparan sulfate 6-O-endosulfatases that regulate the activity of
multiple growth factors, such as fibroblast growth factor and Wnt, and are essential for
mammalian development and survival. In this study, the mammalian Sulfs were functionally
characterized using overexpressing cell lines, in vitro enzyme assays, and in vivo Sulf knock-
out cell models. Analysis of subcellular Sulf localization revealed significant differences in
enzyme secretion and detergent solubility between the human isoforms and their previously …