HS3ST4 (Heparan Sulfate-Glucosamine 3-Sulfotransferase 4): HS3ST4 is an enzyme that modifies heparan sulfate, a vital component of the extracellular matrix. This modification plays a key role in cell signaling and blood clotting. Dysregulation of HS3ST4 can impact cellular interactions and may be linked to cancer and vascular disorders.