O-fucosyltransferase that transfers glucose toward fucose with a beta-1,3 linkage. Specifically glucosylates O-linked fucosylglycan on TSP type-1 domains of proteins, thereby contributing to elongation of O-fucosylglycan. Defects in B3GALTL are the cause of Peters-plus syndrome (PpS). PpS is an autosomal recessive disorder characterized by anterior eye-chamber abnormalities, disproportionate short stature, developmental delay, characteristic craniofacial features, cleft lip and/or palate. Belongs to the glycosyltransferase 31 family. Note: This description may include information from UniProtKB.
Protein type: EC 2.4.1.-; Membrane protein, integral; Transferase