Further protein modification
	Why glycosylation? – Aids in proper protein folding. – Provides protection against proteases (e.g. lysosomal membrane proteins) – Employed for signaling. • Most soluble and membrane-bound proteins made in the ER are glycoproteins, in contrast to cytsolic proteins. • Glycoprotein synthesis is a 3-part process: 1. Assembly of the precursor oligosaccharide 2. En-bloc transfer to the protein 3. Modification of the oligosaccharide by removal of sugars