Glycosyl Phosphatidylinositol-Linked Glycoconjugates:Structure, Biosynthesis and function
The purpose of this review is to summarize the most recent advances on GPI research. tructural studies on GPI-linked glycoconjugates indicate that there are significant ariations in different organisms, although there is a conserved core structure. Furthermore, tructural studies suggest that in different cell types, there is an army oflycosyltransferases dedicated to the synthesis of GPI-linked glycoconjugates. Bio-hemical studies on the synthesis of these GPI-linked glycoconjugates suggest that not only many different enzymes are involved but also that enzymes from different cell types, nvolving in the conserved core structure can have different substrate specificity. Genetic loning of the yeast genes involved in synthesizing the core structure suggests that many of hese enzymes also have human homologues. However, paroxysmal nocturnal emogobinuria (PNH) is the only known human disease associated with the synthesis of GPI-linked glycoconjugates. Functional studies suggest that GPI-anchor can act as a signal or protein sorting and localization. Furthermore, GPI-linked receptors play an important ole in T-cell activation.
KeywordsFolate Integrin Sorting Plasminogen Transferrin
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