α2,3/α2,6-Sialylation of N-glycans: non-synonymous signals with marked developmental regulation in bovine reproductive tracts

摘要: Abstract The glycan part endows cellular glycoconjugates with significant potential for biological recognition. N-Glycan branches often end α2,3/α2,6-sialylation, posing the question whether and how placement of sialic acid at 3´- or 6´-acceptor positions galactose has cell relevance. As attractive model to study developmental regulation we monitored expression α2,3/α2,6-sialylated determinants in fetal adult bovine testes ovaries by lectin histochemistry. Distinct patterns were detected both organ types. Oocyte staining, as a prominent example, was restricted presence α2,6-sialylated glycans. Treatment sialidase abolished binding thus excluded sulfate esters targets. We added computer simulations rationalize observed evidence non-random two closely related sialylgalactose isomers. Extensive molecular mechanics dynamics calculations reveal that seemingly minor shift glycosidic bond from α2,3 position α2,6 configuration causes shape flexibility changes. They give each disaccharide its own characteristic meaning signal sugar code.