Sphingomyelin and glycolipids are synthesized from ceramide in the Golgi. Transport from the TGN to lysosomes. Lysosomes contain acid hydrolyses. Lysosomal pH about 5. Lysosomes are very heterogeneous.
Vacuoles are the lysosome functional equivalent in plant cells.
Autophagy , or the gradual turn over of the cell s own components. Sorting of soluble lysosomal hydrolyses. The M6P groups are recognized by M6P receptor proteins , which bind its specific oligosaccharide at pH 7 in the TGN and releases it at pH 6 in the late endosome, which will give rise to a lysosome. The first is a phosphotransferase with a recognition site that binds the hydrolase and a separate catalytic site that adds the PO 4 . The signal recognized by the recognition site is a conformation-dependent signal patch in the hydrolase.