Sulfotransferase that utilizes 3'-phospho-5'-adenylyl sulfate (PAPS) as sulfonate donor to catalyze the transfer of sulfate to position 6 of non-reducing N-acetylglucosamine (GlcNAc) residues of keratan ( , ). Cooperates with B4GALT4 galactosyltransferase and B3GNT7 N-acetylglucosaminyltransferase to construct and elongate the sulfated disaccharide unit [->3Galbeta1->4(6-sulfoGlcNAcbeta)1->] within keratan sulfate polymer. Involved in biosynthesis of keratan sulfate in cornea, with an impact on proteoglycan fibril organization and corneal transparency ( ). Involved in sulfation of endothelial mucins such as GLYCAM1 .
Subcellular locations: Golgi apparatus membrane
Expressed in cornea. Mainly expressed in brain. Also expressed in spinal cord and trachea.