Cell Adhesions, Junctions, and Extracellular Structures

Adhesive Junctions

Link cells together, anchoring the cytoskeleton to enable cell function as a unit against mechanical stress.

Cadherins

Transmembrane proteins crucial for cell-cell adhesion, characterized by calcium-dependent binding.

Epithelial-Mesenchymal Transition (EMT)

A process involving changes in cadherin expression leading to the breakdown of epithelium into migratory mesenchymal cells.

Tight Junctions (TJs)

Structures that create impermeable seals between epithelial cells, regulating molecule movement across cell layers.

Connexons

Hollow cylindrical assemblies of connexin protein subunits that form open channels in gap junctions.

Extracellular Matrix (ECM)

A non-cellular component of tissues providing structural support, facilitating cellular processes, and defining tissue properties.

Collagens

The most abundant ECM component in animals, forming fibers with high tensile strength.

Integrins

Large family of transmembrane proteins that connect the cytoskeleton with the extracellular matrix.

Proteoglycans

Glycoproteins with glycosaminoglycans attached, providing the hydrated matrix of the ECM.

Plasmodesmata

Cytoplasmic channels in plant cell walls allowing direct communication between adjacent cells.