Accumulation of membrane glycoproteins in lysosomes requires a tyrosine residue at a particular position in the cytoplasmic tail.

• DOI: 10.1083/jcb.111.3.955
• Publication Date: 2004-05-15T00:18:20Z
• Authors: M A Williams; M Fukuda
• Keywords: Membrane glycoproteins; Protein Sorting Signals; Cell membrane

Human lysosome membrane glycoprotein h-lamp-1 is a highly N-glycosylated protein found predominantly in lysosomes, with low levels present at the cell surface. The signal required for delivery of to lysosomes was investigated by analyzing intracellular distribution altered amino acid sequences expressed from mutated cDNA clones. A cytoplasmic tail tyrosine residue conserved chicken, rodent, and human deduced discovered be necessary efficient lysosomal transport COS-1 cells. In addition, position relative carboxyl terminus also determined expression. Supplanting wild-type onto surface reporter sufficient cause redistribution chimera lysosomes. similar chimeric replacing an alanine not Altered proteins that were transported accumulate surface, unlike glycoproteins, unable undergo endocytosis. These data indicate glycoproteins are sorted containing specific position, sorting may recognized both trans-Golgi network