Potential roles of N-glycosylation in cell adhesion

Abstract

The functional units of cell adhesion are typically multiprotein complexes made up of three general classes of proteins; the adhesion receptors, the cell-extracellular matrix (ECM) proteins, and the cytoplasmic plaque/peripheral membrane proteins. The cell adhesion receptors are usually transmembrane glycoproteins (for example E-cadherin and integrin) that mediate binding at the extracellular surface and determine the specificity of cell-cell and cell-ECM recognition. E-cadherin-mediated cell-cell adhesion can be both temporally and spatially regulated during development, and represents a key step in the acquisition of the invasive phenotype for many tumors. On the other hand, integrin-mediated cell-ECM interactions play important roles in cytoskeleton organization and in the transduction of intracellular signals to regulate various processes such as proliferation, differentiation and cell migration. ECM proteins are typically large glycoproteins, including the collagens, fibronectins, laminins, and proteoglycans that assemble into fibrils or other complex macromolecular arrays. The most of these adhesive proteins are glycosylated. Here, we focus mainly on the modification of N-glycans of integrins and laminin-332, and a mutual regulation between cell adhesion and bisected N-glycan expression, to address the important roles of N-glycans in cell adhesion.

Glycans and Cancer

“…The expression of GnT-III was found to be upregulated by E-cadherin-mediated cell adhesion. A significant upregulation of GnT-III was observed only in epithelial cells that express E-cadherin (Gu, Isaji, Sato, Kariya, & Fukuda, 2009;Gu et al, 2012), but not in E-cadherin-deficient cells. This regulation appeared to involve actin cytoskeleton formation, as indicated by disruption of polymerization by cytochalasin D or by a lack of α-catenin expression (Akama et al, 2008;Iijima et al, 2006).…”

Novel function of pregnancy-associated plasma protein A: promotes endometrium receptivity by up-regulating N-fucosylation

“…N-linked glycans carried by integrins are involved in cell-cell and cell-extracellular matrix (ECM) interactions, thus modulating cell adhesion, proliferation, differentiation and migration by transferring signals from ECM to the cells 51 . For example, elevated α2,3-sialic acid levels of α2β1 by the overexpression of ST3Gal III promoted pancreatic cancer cell adhesion to type 1 collagen, and the activation of phosphorylated FAK 52 .…”

Fetal Environment and Glycosylation Status in Neonatal Cord Blood

“…In particular, N-glycan plays a crucial role in major human biological processes, such as cell–matrix interactions, protein folding, receptor binding, and protein clearance. 10–12 Whereas changes in serum N-glycans were considered to be novel diagnostic biomarkers of various diseases, especially different types of cancer, 13,14 the highly complicated structures of N-glycans and difficulty in processing for their separation from complex mixtures hindered the progress of glycomics. However, emerging technologies have currently made it more feasible to acquire high throughput of glycome profiling.…”