Neurotransmitter Transporters: Is Glycosylation Necessary for Function?
A detailed description of the glycosylation of proteins is beyond the scope of this chapter. A brief outline of the process of glycosylation is described (Fig. 1). Emerging nascent polypeptide in the rough endoplasmic reticulum acquires a core of oligosaccharide from dolichol pyrophosphate catalyzed by glycosyltransferase (Hirschberg and Snider, 1987). This initial core of sugar residues (two N-acetylglucosamine(GlcNAc), nine mannose and three glucose residues) undergoes post-translational processing in endoplasmic reticulum and golgi to yield a final form of the oligosaccharide core. The specificity of sugar residues in the core is due to the presence of specific glycosyltransferases which are cell and tissue specific (Hubbard and Ivat, 1981; Kornfeld and Kornfeld, 1985).
KeywordsSugar Serotonin Serine Proline Norepinephrine
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