DC-SIGN

DC-SIGN (Dendritic Cell-Specific Intercellular adhesion molecule-3-Grabbing Non-integrin) is a protein that in humans is encoded by the CD209 gene. It is a type of C-type lectin which is expressed on the surface of dendritic cells and functions as a receptor for many viruses, including HIV, Ebola virus, and the SARS coronavirus.

Structure

DC-SIGN is a type of C-type lectin, which are carbohydrate-binding proteins. It is composed of a C-terminal carbohydrate recognition domain (CRD), a neck region, a transmembrane domain, and a cytoplasmic tail. The CRD allows DC-SIGN to bind to specific sugar molecules on the surface of pathogens, while the neck region helps to form a tetramer structure that enhances binding.

Function

The primary function of DC-SIGN is to capture and internalize pathogens for presentation to T cells. This is a crucial step in the immune response. DC-SIGN binds to a variety of pathogens, including bacteria, fungi, and viruses. It is particularly well-known for its role in HIV infection. DC-SIGN captures HIV and facilitates its transport to the lymph nodes, where the virus can infect T cells.

Clinical significance

Due to its role in viral infections, DC-SIGN is a potential target for antiviral therapies. Inhibiting the interaction between DC-SIGN and viruses could prevent the spread of infection. Additionally, variations in the DC-SIGN gene have been associated with susceptibility to certain infectious diseases, including tuberculosis and dengue fever.

See also

• C-type lectin
• Dendritic cell
• HIV
• Ebola virus
• SARS coronavirus