<unk> s <unk> s) are proteins located on the<unk>  surface involved with the binding with other<unk> s or with the extracellular matrix (ECM) in the process called<unk><unk> .
These proteins are typically transmembrane receptors and are composed of three domains: an intracellular domain that interacts with the cytoskeleton, a transmembrane domain and an extracellular domain that interacts either with other<unk> s of the same kind (homophilic binding) or with other<unk> s or the extracellular matrix (heterophilic binding).
Cell adhesion molecule
Disintegrin
Pattern recognition receptor
Receptor 
Fibroblast growth factor receptor
Soluble CD40 ligand 
Tumor necrosis factor receptor
Interleukin-8 receptor