The majority of proteins that traverse the secretory pathway receive asparagine (Asn)-linked glycosylations.
Glycans are bulky hydrophilic modifications that serve a variety of structural and functional roles within the cell.
The role of Asn-linked glycans is proteic maturation and quality-control protein tags in the early secretory pathway.
The carbohydrate composition encodes crucial information about the structure, localization and age of glycoproteins.
The "glycan code" is encoded by a series of glycosidases and carbohydrate transferases that line the secretory pathway.
This code is deciphered by carbohydrate-binding proteins that possess distinct carbohydrate binding properties and act as molecular chaperones or sorting receptors.
These glycosidases and transferases work in concert with resident secretory pathway carbohydrate-binding proteins to form a network that assists in the maturation and trafficking of both native and aberrant glycoproteins within the cell.
See also
protein maturation
Video
References
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