Desmosome

Desmosomes (Greek δεσμός Desmos "Connection" and σῶμα soma " body " ) are cellular structures in cell membranes, the close connections between two disk-shaped cells produce. They are particularly significant in cells with intense mechanical stress such as epithelial cells and some non- epithelial tissues such as the heart muscles, before and improve the mechanical integrity (protection against shear forces). This is done primarily by the fact that they combine the cell's own intermediate filaments with those of other cells. In the epithelial cells of these are usually the keratin filaments and cardiac muscle desmin filaments.

Desmosomes ( macula adherens ) appear as spherical condensations on the side walls of epithelial cells - with snaps or rivets comparable. The intercellular space is partially slightly broadened at these sites, since it is filled with filamentous material ( glycoproteins and mucopolysaccharides ), similar to a cement substance.

Found on the inside of the cell membrane at these points plate-like structures made of desmoplakin. In this are numerous, tapering from the entire cell interior to the point, not contractile fibril bundles of keratin, the so-called tonofilaments anchored. Since these through the entire cell in its further course, they link the Desmosom with the cytoskeleton and thus stabilize its location on the cell surface.

Through the joint ( plaque) protrude homotypic binding cadherins ( desmoglein and desmocollin ), which are also enshrined in the Zytoplasmaplatte. You connect to the intercellular space with cadherins from other cells, thus providing a connection.

Autoantibodies against desmoglein lead to the clinical picture of pemphigus vulgaris.

Hemidesmosomes are desmosomartige compounds, but not two similar cell membranes like cells, but the cell membrane of a cell with a basal lamina connect, such as epithelia.