Lateral dimerization of the E-cadherin extracellular domain is necessary but not sufficient for adhesive activity.
Abstract
Cadherins are transmembrane glycoproteins involved in Ca(2+)-dependent cell-cell adhesion. Using L cells coexpressing E-cadherin constructs with different epitope tags, we examined the lateral dimerization of E-cadherin and its adhesive activity by co-immunoprecipitation and aggregation assays, respectively. Although the transmembrane domain is required for dimerization, tail-less constructs possessing the transmembrane domain of either N-cadherin or CD45 show dimerization and are active in aggregation assays. Two mutant constructs having either of two amino acid substitutions, W2A or substitutions that disrupt the recognition sequence for endoproteolytic enzymes involved in removal of the precursor segment, cannot form dimers and are inactive in aggregation. These monomeric proteins, like their wild-type dimerizing counterparts, retain their Ca(2+)-dependent resistance to trypsin digestion, suggesting that dimerization per se does not induce a large conformational change. Two other constructs, having either an amino acid substitution, D134A, or a C-terminal deletion of 70 amino acid residues, retain the ability to associate laterally but are inactive in aggregation assays. Staurosporine treatment of cells expressing the latter...Continue Reading
References
Single amino acid substitutions in one Ca2+ binding site of uvomorulin abolish the adhesive function
Citations
Related Concepts
Related Feeds
ASBMB Publications
The American Society for Biochemistry and Molecular Biology (ASBMB) includes the Journal of Biological Chemistry, Molecular & Cellular Proteomics, and the Journal of Lipid Research. Discover the latest research from ASBMB here.
Adherens Junctions
An adherens junction is defined as a cell junction whose cytoplasmic face is linked to the actin cytoskeleton. They can appear as bands encircling the cell (zonula adherens) or as spots of attachment to the extracellular matrix (adhesion plaques). Adherens junctions uniquely disassemble in uterine epithelial cells to allow the blastocyst to penetrate between epithelial cells. Discover the latest research on adherens junctions here.
Cadherins and Catenins
Cadherins (named for "calcium-dependent adhesion") are a type of cell adhesion molecule (CAM) that is important in the formation of adherens junctions to bind cells with each other. Catenins are a family of proteins found in complexes with cadherin cell adhesion molecules of animal cells: alpha-catenin can bind to β-catenin and can also bind actin. β-catenin binds the cytoplasmic domain of some cadherins. Discover the latest research on cadherins and catenins here.
Adhesion Molecules in Health and Disease
Cell adhesion molecules are a subset of cell adhesion proteins located on the cell surface involved in binding with other cells or with the extracellular matrix in the process called cell adhesion. In essence, cell adhesion molecules help cells stick to each other and to their surroundings. Cell adhesion is a crucial component in maintaining tissue structure and function. Discover the latest research on adhesion molecule and their role in health and disease here.