What is the Difference Between Adherens Junctions and Desmosomes?

Adherens junctions and desmosomes are both intercellular adhesive structures essential for the development and integrity of vertebrate tissues. They are formed from cadherin molecules, but there are key differences between them:

1. Cadherin Type: Adherens junctions use type 1 cadherins, while desmosomes use desmosomal cadherins like desmoglein and desmocollin.
2. Cell Adhesion: Adherens junctions join the actin filaments of neighboring cells together, while desmosomes join the intermediate filaments of neighboring cells.
3. Extracellular Structure: Adherens junctions lack a highly ordered structure in their extracellular region, whereas desmosomes have a highly ordered structure in their extracellular region.
4. Calcium Dependence: Adherens junctions are always calcium-dependent, while desmosomes are calcium-independent hyper-adhesions.
5. Plaque Proteins: Adherens junctions do not contain plaque proteins, but desmosomes consist of distinguishable plaque proteins.

In summary, adherens junctions and desmosomes are both cadherin-based intercellular adhesive structures, but they differ in the type of cadherin, the cell adhesion molecules they link, the structure of their extracellular regions, their calcium dependence, and the presence of plaque proteins.

Comparative Table: Adherens Junctions vs Desmosomes

Here is a table comparing the differences between adherens junctions and desmosomes:

Adherens junctions and desmosomes are intercellular adhesive structures that provide adhesion and cohesion between cells. Both consist of cell adhesion molecules, but they have distinct structures and functions. Adherens junctions are built from cadherins, which are transmembrane proteins that bind to each other and connect to actin filaments. Desmosomes, on the other hand, are formed by desmoglein and desmocollin, which are also cadherins but connect to intermediate filaments.