Subcellular location of two enzymes involved in the synthesis of phosphorylated recognition markers in lysosomal enzymes.

Phosphorylated recognition markers in lysosomal enzyme appear to be synthesized by transfer of alpha-N-acetylglucosamine 1-phosphate groups to C6 hydroxyl of mannose residues in glycosylated enzyme precursors and a subsequent hydrolysis from the diester groups of the N-acetylglucosamine residues. The transfer and the diesterase activities were studied in subcellular fractions of rat liver. Both activities fractionated like the Golgi marker galactosyltransferase.