Sandbox UC 15

From Proteopedia

Cadherins are one of the many molecules that glue cells together. They are long proteins that extend from the surface of the cell. The outer portion is composed of a series of folded domains arranged one after the next, and bind between each domain, rigidifying the whole structure. If calcium is removed, however, the chain becomes floppy and is easily destroyed by protein-cutting enzymes. The tip of the chain has a special amino acid, that binds to cadherins on neighboring cells, adhering the two cells together.

The tail of the cadherin chain crosses the cell membrane (shown schematically in gray) and is linked to the cytoskeleton by catenin proteins. Beta-catenin (shown here in blue from PDB entry 1i7x) binds to the small tail of cadherin that hangs inside the cell. Alpha-catenin (not shown) then binds to beta-catenin and actin filaments.