Tetraspannins

Tetraspannins are a family of integral membrane proteins that play crucial roles in various cellular processes. They are characterized by their tetraspan topology, which consists of four transmembrane domains connected by extracellular and intracellular loops. Tetraspannins are found in the plasma membrane and are involved in cell adhesion, signaling, and trafficking.

One of the most well-known tetraspannins is CD81, which is involved in the trafficking of low-density lipoprotein (LDL) receptors and is a marker for certain types of cancer cells. Another important tetraspannin is CD82, which is involved in cell adhesion and is a marker for melanoma cells.

Tetraspannins are also involved in the formation of lipid rafts, which are specialized microdomains in the plasma membrane that play important roles in signaling and trafficking. They are thought to function as scaffolds that organize and stabilize lipid rafts.

The tetraspannin family is large and diverse, with over 100 members identified in humans. They are involved in a wide range of biological processes, including cell adhesion, signaling, trafficking, and differentiation. Despite their diversity, tetraspannins share a common tetraspan topology and are thought to function through similar mechanisms.

In summary, tetraspannins are a family of integral membrane proteins that play crucial roles in various cellular processes. They are characterized by their tetraspan topology and are involved in cell adhesion, signaling, and trafficking. They are also involved in the formation of lipid rafts and are thought to function as scaffolds that organize and stabilize these microdomains. The tetraspannin family is large and diverse, with over 100 members identified in humans.