Heparan Sulfate-3-O-Sulfotransferase 6 (HS3ST6)

In dry eye, 46 glycogenes were significantly downregulated, including five members of the Notch signaling pathway (Notch1, Notch 2, Notch 3, Jagged1, Delta1), four Wnt signaling molecules (Wnt4, -5A, Frizzled6, -7), and three heparan sulfate glycotransferases (HS2ST1, HS3ST6, EXTL2). Only interferon-induced transmembrane protein 1 was upregulated.

HS3ST6 is a single-pass type II membrane protein. It belongs to the sulfotransferase 1 family. It transfers a sulfuryl group to heparan sulfate. The substrate-specific O-sulfation generates an enzyme-modified heparan sulfate which acts as a binding receptor to Herpes Simplex Virus-1 (HSV-1) and permits its entry. Unlike 3-OST-1, does not convert non-anticoagulant heparan sulfate to anticoagulant heparan sulfate.