Molecular recognition and targeting of lysosomal proteins.

Recent studies have established that in mammalian cells insulin-like growth factor-II can couple the large mannose-6-phosphate receptor to a GTP-binding protein and that the insulin-like growth factor-II-induced activation of the GTP-binding protein is inhibited by mannose-6-phosphate and lysosomal enzymes. In mouse, the gene for the large mannose-6-phosphate receptor is maternally imprinted.