O-Linked Glycosylation

 Definition: O-linked glycosylation refers to the attachment of monosaccharides to the hydroxyl group of serine (Ser), threonine (Thr), or tyrosine (Tyr) residues. Unlike N-linked glycosylation, O-linked glycosylation does not have a specific sequence motif guiding its attachment.

Process

Location: O-linked glycosylation occurs primarily in the Golgi apparatus after the protein has been fully translated and folded.

Structure: This type of glycosylation typically involves the sequential addition of individual sugar units, resulting in shorter chains compared to N-linked glycans. O-linked glycans generally do not extend beyond a few residues 

Function: O-linked glycans are involved in various biological processes, including cell signalling, immune response modulation, and protein stability. They can also influence how proteins interact with other molecules.