The Importance of N- and O-Glycosylation of Brain Cell Surface Glycoproteins.

The mammalian brain is unique in its cell types, mainly neurons and glial cells, and the glycoproteins expressed by these cells. Two of the most abundant types of modifications of cell surface glycoproteins are N-glycans linked to Asn residues and O-glycans linked via GalNAc to Ser/Thr residues. Recent studies focused on glycoproteomics, glycomics and glycan localization in the brain reveal major differences in these protein modifications compared to other organs. Deficiencies in glycosylation are associated with the development of multiple brain disorders such as congenital disorders of glycosylation (CDG) that include brain structural abnormalities, epilepsy and seizures to more common disorders including schizophrenia and Alzheimer's disease. Here we summarize recent advances in the growing field of neuro-glycobiology and highlight key points that could be used as primer for future studies.