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A desmosome (; "binding body"), also known as a macula adhaerens (plural: maculae adhaerentes) (Latin for ''adhering spot''), is a cell structure specialized for cell-to-cell adhesion. A type of junctional complex, they are localized spot-like adhesions randomly arranged on the lateral sides of plasma membranes. Desmosomes help to resist shearing forces and are found in simple and stratified squamous epithelium. The intercellular space is very wide (about 30 nm). Desmosomes are also found in muscle tissue where they bind muscle cells to one another. ==Structure== Desmosomes are molecular complexes of cell adhesion proteins and linking proteins that attach the cell surface adhesion proteins to intracellular keratin cytoskeletal filaments. The cell adhesion proteins of the desmosome, desmoglein and desmocollin, are members of the cadherin family of cell adhesion molecules. They are transmembrane proteins that bridge the space between adjacent epithelial cells by way of homophilic binding of their extracellular domains to other desmosomal cadherins on the adjacent cell. Both have five extracellular domains, and have calcium-binding vulvae. The extracellular domain of the desmosome is called the extracellular core domain (ECD) or the desmoglea, and is bisected by an electron-dense midline where the desmoglein and desmocollin proteins bind to each other. These proteins can bind in a W, S, or λ manner. On the cytoplasmic side of the plasma membrane, there are two dense structures called the outer dense plaque (ODP) and the inner dense plaque (IDP). These are spanned by the desmoplakin protein. The outer dense plaque is where the cytoplasmic domains of the cadherins attach to desmoplakin via plakoglobin and plakophilin. The Inner Dense Plaque is where desmoplakin attaches to the intermediate filaments of the cell. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「desmosome」の詳細全文を読む スポンサード リンク
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