Desmosomes

Desmosomes (Maculae adherens)

Definition: Disc shaped adhesive junction containing cadherins found in a variety of tissues, but most notably epithelia, where they are located basal to adherens junction. Dense cytoplasmic plaques on the inner surface of the plasma membrane in this region serves as sites of anchorage for looping intermediate filaments that extend into the cytoplasm.

• Anchoring junctions called desmosomes connect the cytoskeleton of adjacent cells
• Button like weids joining opposing cell membranes
• Cadherins bind the membranes of adjacent cells in a way that gives strength and rigidity to the entire tissue

Molecular structure of desmosomes

Intermediate filaments of cytoskeleton linked to adjoining cells through cadherins

Two cadherins

• Desmoglein
• Desmocollin

Adaptor proteins: Plakoglobin and desmoplakin

Linked to epidermal keratins

Example- Epithelium