Plakoglobin, or an 83-kD homologue distinct from beta-catenin, interacts with E-cadherin and N-cadherin.
E- and N-cadherin are members of a family of calcium-dependent, cell surface glycoproteins involved in cell-cell adhesion. Extracellularly, the transmembrane cadherins self-associate, while, intracellularly, they interact with the actin-based cytoskeleton. Several intracellular proteins, collectively termed catenins, have been noted to co-immunoprecipitate with E- and N-cadherin and are thought to be involved in linking the cadherins to the cytoskeleton. Two catenins have been identified recently: a 102-kD vinculin-like protein (alpha-catenin) and a 92-kD Drosophila armadillo/plakoglobin-like protein (beta-catenin). Here, we show that plakoglobin, or an 83-kD plakoglobin-like protein, co-immunoprecipitates and colocalizes with both E- and N-cadherin. The 83-kD protein is immunologically distinct from the 92-kD beta-catenin and, because of its molecular mass, likely represents the cadherin-associated protein called gamma-catenin. Thus, two different members of a plakoglobin family associate with N- and E-cadherin and, together with the 102-kD alpha-catenin, appear to participate in linking the cadherins to the actin-based cytoskeleton.
Knudsen
K A
KA
Lankenau Medical Research Center, Wynnewood, Pennsylvania 19096.
Wheelock
M J
MJ
D000818:Animals; D015820:Cadherins / Q000737:chemistry / Q000378:metabolism*; D015815:Cell Adhesion Molecules / Q000378:metabolism*; D002478:Cells, Cultured; D002642:Chick Embryo; D003598:Cytoskeletal Proteins / Q000378:metabolism*; D051180:Desmoplakins; D005455:Fluorescent Antibody Technique; D011233:Precipitin Tests; D015534:Trans-Activators; D051176:beta Catenin; D051185:gamma Catenin
D015820:Cadherins; D015815:Cell Adhesion Molecules; D003598:Cytoskeletal Proteins; D051180:Desmoplakins; D015534:Trans-Activators; D051176:beta Catenin; D051185:gamma Catenin