HS3ST4 Gene: Function, Expression, and Disease Associations | Biomedical Database

HS3ST4 encodes a member of the heparan sulfate 3-O-sulfotransferase family. This enzyme catalyzes the transfer of sulfate to the 3-OH position of glucosamine residues in heparan sulfate, generating specific binding sites for proteins such as antithrombin III and herpes simplex virus glycoprotein D. HS3ST4 is involved in the biosynthesis of heparan sulfate, a glycosaminoglycan that plays critical roles in cell signaling, growth factor binding, and cell adhesion. The gene is expressed in various tissues, with notable expression in the brain and placenta. Alterations in HS3ST4 expression have been implicated in several cancers and developmental processes.

Tissue Expression

Cell Line Expression

Hotspot Mutations

Mutation functional classification

• Heparan sulfate biosynthesis

• Glycosaminoglycan metabolism

• Herpes simplex virus entry

The HS3ST4 protein is a type II transmembrane enzyme localized to the Golgi apparatus. It consists of a short cytoplasmic tail, a transmembrane domain, and a luminal catalytic domain. The enzyme transfers sulfate from 3'-phosphoadenosine 5'-phosphosulfate (PAPS) to the 3-OH position of glucosamine in heparan sulfate. This modification creates specific binding sites for antithrombin III, contributing to anticoagulant activity, and for viral glycoproteins, facilitating viral entry. The protein is ~40 kDa in size and is expressed in a tissue-specific manner.