Tissue-specific glycosylation

There are extensive additional tissue-specific modifications of these peptides that affect activity. These modifications include phosphorylation, acetylation, glycosylation, and amidation. 

A number of cases are known in which the same protein produced in two types of tissues has different glycosylation patterns. For example, the human protein interferon IFN-/31 has one set of oligosaccharide chains when produced in ovarian cells and a different set when produced in breast epithelial cells. The biological significance of these tissue glycoforms is not understood, but in some way the oligosaccharide chains represent a tissue-specific marker. 

Tissue and physio-pathological specific glycosylation repertoire of mucins... 

Another set of reactions involving retinol that has been studied in liver concerns the formation of retinyl phosphate and of retinyl phosphomannose conjugates. These studies have been directed toward the hypothesis that retinoid-containing glycolipids serve as intermediates for specific glycosylation reactions. It is well established that the biosynthesis of some glycoproteins is markedly decreased in a number of tissues in retinoid deficiency, and that glycoprotein... 

Alavi A, Axford JS, Hay FC, Jones MG. Tissue-specific galactosyltransferase abnormalities in an experimental model of rheumatoid arthritis. Ann Med Intern (1998) 149(5) 251-260. Axford JS, Sumar N, Alavi A, Isenberg DA, Young A, Bodman KB, Roitt IM. Changes in normal glycosylation mechanisms in autoimmune rheumatic disease. J Clin Invest (1992) 89(3) 1021-1031. 

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