sentences:  Tyrosylprotein sulfotransferase (TPST) is a type II transmembrane protein.It consists of a short cytosolic region that contains the N-terminus of the protein, a single transmembrane region of about 17 amino acids in length, a small stem region of about 40 amino acids in length, and a larger, catalytic region that is located on the luminal side of the membrane.It is localized to the Golgi apparatus, specifically in the "trans"-Golgi region, and acts almost exclusively on secretory and plasma membrane proteins.