Catalyzes the transfer of sulfate to beta-1,3-linked galactose residues in O-linked glycoproteins. Good substrates include asialofetuin, Gal-beta-1,3-GalNAc and Gal-beta-1,3 (GlcNAc-beta-1,6)GalNAc.
Subcellular locations: Golgi apparatus, Golgi stack membrane
Expressed mainly in placenta, thymus, testis, ovary, spinal cord, trachea and adrenal gland and at low levels in brain, lung, spleen, prostate, small intestine, colon, stomach thyroid and lymph node.